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README.md
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# Simple DirectMedia Layer (SDL) Version 3.0
https://www.libsdl.org/
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
More extensive documentation is available in the docs directory, starting
with [README.md](docs/README.md). If you are migrating to SDL 3.0 from SDL 2.0,
the changes are extensively documented in [README-migration.md](docs/README-migration.md).
Enjoy!
Sam Lantinga (slouken@libsdl.org)
# Simple DirectMedia Layer (SDL) Version 3.0
https://www.libsdl.org/
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
More extensive documentation is available in the docs directory, starting
with [README.md](docs/README.md). If you are migrating to SDL 3.0 from SDL 2.0,
the changes are extensively documented in [README-migration.md](docs/README-migration.md).
Enjoy!
Sam Lantinga (slouken@libsdl.org)

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# CMake
[www.cmake.org](https://www.cmake.org/)
The CMake build system is supported on the following platforms:
* FreeBSD
* Linux
* Microsoft Visual C
* MinGW and Msys
* macOS, iOS, and tvOS, with support for XCode
* Android
* Emscripten
* FreeBSD
* Haiku
* Nintendo 3DS
* Playstation 2
* Playstation Vita
* QNX 7.x/8.x
* RiscOS
## Building SDL
Assuming the source tree of SDL is located at `~/sdl`,
this will configure and build SDL in the `~/build` directory:
```sh
cmake -S ~/sdl -B ~/build
cmake --build ~/build
```
Installation can be done using:
```sh
cmake --install ~/build --prefix /usr/local # '--install' requires CMake 3.15, or newer
```
This will install SDL to /usr/local.
### Building SDL tests
You can build the SDL test programs by adding `-DSDL_TESTS=ON` to the first cmake command above:
```sh
cmake -S ~/sdl -B ~/build -DSDL_TEST_LIBRARY=ON -DSDL_TESTS=ON
```
and then building normally. In this example, the test programs will be built and can be run from `~/build/tests/`.
## Including SDL in your project
SDL can be included in your project in 2 major ways:
- using a system SDL library, provided by your (*nix) distribution or a package manager
- using a vendored SDL library: this is SDL copied or symlinked in a subfolder.
The following CMake script supports both, depending on the value of `MYGAME_VENDORED`.
```cmake
cmake_minimum_required(VERSION 3.5)
project(mygame)
# Create an option to switch between a system sdl library and a vendored SDL library
option(MYGAME_VENDORED "Use vendored libraries" OFF)
if(MYGAME_VENDORED)
# This assumes you have added SDL as a submodule in vendored/SDL
add_subdirectory(vendored/SDL EXCLUDE_FROM_ALL)
else()
# 1. Look for a SDL3 package,
# 2. look for the SDL3-shared component, and
# 3. fail if the shared component cannot be found.
find_package(SDL3 REQUIRED CONFIG REQUIRED COMPONENTS SDL3-shared)
endif()
# Create your game executable target as usual
add_executable(mygame WIN32 mygame.c)
# Link to the actual SDL3 library.
target_link_libraries(mygame PRIVATE SDL3::SDL3)
```
### A system SDL library
For CMake to find SDL, it must be installed in [a default location CMake is looking for](https://cmake.org/cmake/help/latest/command/find_package.html#config-mode-search-procedure).
The following components are available, to be used as an argument of `find_package`.
| Component name | Description |
|----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| SDL3-shared | The SDL3 shared library, available through the `SDL3::SDL3-shared` target |
| SDL3-static | The SDL3 static library, available through the `SDL3::SDL3-static` target |
| SDL3_test | The SDL3_test static library, available through the `SDL3::SDL3_test` target |
| SDL3 | The SDL3 library, available through the `SDL3::SDL3` target. This is an alias of `SDL3::SDL3-shared` or `SDL3::SDL3-static`. This component is always available. |
| Headers | The SDL3 headers, available through the `SDL3::Headers` target. This component is always available. |
### Using a vendored SDL
This only requires a copy of SDL in a subdirectory + `add_subdirectory`.
Alternatively, use [FetchContent](https://cmake.org/cmake/help/latest/module/FetchContent.html).
Depending on the configuration, the same targets as a system SDL package are available.
## CMake configuration options
### Build optimized library
By default, CMake provides 4 build types: `Debug`, `Release`, `RelWithDebInfo` and `MinSizeRel`.
The main difference(s) between these are the optimization options and the generation of debug info.
To configure SDL as an optimized `Release` library, configure SDL with:
```sh
cmake ~/SDL -DCMAKE_BUILD_TYPE=Release
```
To build it, run:
```sh
cmake --build . --config Release
```
### Shared or static
By default, only a shared SDL library is built and installed.
The options `-DSDL_SHARED=` and `-DSDL_STATIC=` accept boolean values to change this.
### Pass custom compile options to the compiler
- Use [`CMAKE_<LANG>_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_LANG_FLAGS.html) to pass extra
flags to the compiler.
- Use [`CMAKE_EXE_LINKER_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_EXE_LINKER_FLAGS.html) to pass extra option to the linker for executables.
- Use [`CMAKE_SHARED_LINKER_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_SHARED_LINKER_FLAGS.html) to pass extra options to the linker for shared libraries.
#### Examples
- build a SDL library optimized for (more) modern x64 microprocessor architectures.
With gcc or clang:
```sh
cmake ~/sdl -DCMAKE_C_FLAGS="-march=x86-64-v3" -DCMAKE_CXX_FLAGS="-march=x86-64-v3"
```
With Visual C:
```sh
cmake .. -DCMAKE_C_FLAGS="/ARCH:AVX2" -DCMAKE_CXX_FLAGS="/ARCH:AVX2"
```
### iOS/tvOS
CMake 3.14+ natively includes support for iOS and tvOS. SDL binaries may be built
using Xcode or Make, possibly among other build-systems.
When using a recent version of CMake (3.14+), it should be possible to:
- build SDL for iOS, both static and dynamic
- build SDL test apps (as iOS/tvOS .app bundles)
- generate a working SDL_build_config.h for iOS (using SDL_build_config.h.cmake as a basis)
To use, set the following CMake variables when running CMake's configuration stage:
- `CMAKE_SYSTEM_NAME=<OS>` (either `iOS` or `tvOS`)
- `CMAKE_OSX_SYSROOT=<SDK>` (examples: `iphoneos`, `iphonesimulator`, `iphoneos12.4`, `/full/path/to/iPhoneOS.sdk`,
`appletvos`, `appletvsimulator`, `appletvos12.4`, `/full/path/to/AppleTVOS.sdk`, etc.)
- `CMAKE_OSX_ARCHITECTURES=<semicolon-separated list of CPU architectures>` (example: "arm64;armv7s;x86_64")
#### Examples
- for iOS-Simulator, using the latest, installed SDK:
```bash
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64
```
- for iOS-Device, using the latest, installed SDK, 64-bit only
```bash
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES=arm64
```
- for iOS-Device, using the latest, installed SDK, mixed 32/64 bit
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES="arm64;armv7s"
```
- for iOS-Device, using a specific SDK revision (iOS 12.4, in this example):
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos12.4 -DCMAKE_OSX_ARCHITECTURES=arm64
```
- for iOS-Simulator, using the latest, installed SDK, and building SDL test apps (as .app bundles):
```cmake
cmake ~/sdl -DSDL_TESTS=1 -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64
```
- for tvOS-Simulator, using the latest, installed SDK:
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=tvOS -DCMAKE_OSX_SYSROOT=appletvsimulator -DCMAKE_OSX_ARCHITECTURES=x86_64
```
- for tvOS-Device, using the latest, installed SDK:
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=tvOS -DCMAKE_OSX_SYSROOT=appletvos -DCMAKE_OSX_ARCHITECTURES=arm64`
```
- for QNX/aarch64, using the latest, installed SDK:
```cmake
cmake ~/sdl -DCMAKE_TOOLCHAIN_FILE=~/sdl/build-scripts/cmake-toolchain-qnx-aarch64le.cmake -DSDL_X11=0
```
## SDL-specific CMake options
SDL can be customized through (platform-specific) CMake options.
The following table shows generic options that are available for most platforms.
At the end of SDL CMake configuration, a table shows all CMake options along with its detected value.
| CMake option | Valid values | Description |
|-------------------------------|--------------|-----------------------------------------------------------------------------------------------------|
| `-DSDL_SHARED=` | `ON`/`OFF` | Build SDL shared library (not all platforms support this) (`libSDL3.so`/`libSDL3.dylib`/`SDL3.dll`) |
| `-DSDL_STATIC=` | `ON`/`OFF` | Build SDL static library (`libSDL3.a`/`SDL3-static.lib`) |
| `-DSDL_TEST_LIBRARY=` | `ON`/`OFF` | Build SDL test library (`libSDL3_test.a`/`SDL3_test.lib`) |
| `-DSDL_TESTS=` | `ON`/`OFF` | Build SDL test programs (**requires `-DSDL_TEST_LIBRARY=ON`**) |
| `-DSDL_DISABLE_INSTALL=` | `ON`/`OFF` | Don't create a SDL install target |
| `-DSDL_DISABLE_INSTALL_DOCS=` | `ON`/`OFF` | Don't install the SDL documentation |
| `-DSDL_INSTALL_TESTS=` | `ON`/`OFF` | Install the SDL test programs |
## Help, it doesn't work!
Below, a SDL3 CMake project can be found that builds 99.9% of time (assuming you have internet connectivity).
When you have a problem with building or using SDL, please modify it until it reproduces your issue.
```cmake
cmake_minimum_required(VERSION 3.16)
project(sdl_issue)
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# !!!!!! !!!!!!
# !!!!!! This CMake script is not using "CMake best practices". !!!!!!
# !!!!!! Don't use it in your project. !!!!!!
# !!!!!! !!!!!!
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# 1. Try system SDL3 package first
find_package(SDL3 QUIET)
if(SDL3_FOUND)
message(STATUS "Using SDL3 via find_package")
endif()
# 2. Try using a vendored SDL library
if(NOT SDL3_FOUND AND EXISTS "${CMAKE_CURRENT_LIST_DIR}/SDL/CMakeLists.txt")
add_subdirectory(SDL)
message(STATUS "Using SDL3 via add_subdirectory")
set(SDL3_FOUND TRUE)
endif()
# 3. Download SDL, and use that.
if(NOT SDL3_FOUND)
include(FetchContent)
set(SDL_SHARED TRUE CACHE BOOL "Build a SDL shared library (if available)")
set(SDL_STATIC TRUE CACHE BOOL "Build a SDL static library (if available)")
FetchContent_Declare(
SDL
GIT_REPOSITORY https://github.com/libsdl-org/SDL.git
GIT_TAG main # Replace this with a particular git tag or git hash
GIT_SHALLOW TRUE
GIT_PROGRESS TRUE
)
message(STATUS "Using SDL3 via FetchContent")
FetchContent_MakeAvailable(SDL)
set_property(DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/_deps/sdl-src" PROPERTY EXCLUDE_FROM_ALL TRUE)
endif()
file(WRITE main.c [===========================================[
/**
* Modify this source such that it reproduces your problem.
*/
/* START of source modifications */
#include <SDL3/SDL.h>
int main(int argc, char *argv[]) {
if (SDL_Init(SDL_INIT_EVERYTHING) < 0) {
SDL_Log("SDL_Init failed (%s)", SDL_GetError());
return 1;
}
SDL_Window *window = NULL;
SDL_Renderer *renderer = NULL;
if (SDL_CreateWindowAndRenderer(640, 480, 0, &window, &renderer) < 0) {
SDL_Log("SDL_CreateWindowAndRenderer failed (%s)", SDL_GetError());
SDL_Quit();
return 1;
}
SDL_SetWindowTitle(window, "SDL issue");
while (1) {
int finished = 0;
SDL_Event event;
while (SDL_PollEvent(&event)) {
if (event.type == SDL_EVENT_QUIT) {
finished = 1;
break;
}
}
if (finished) {
break;
}
SDL_SetRenderDrawColor(renderer, 80, 80, 80, SDL_ALPHA_OPAQUE);
SDL_RenderClear(renderer);
SDL_RenderPresent(renderer);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
}
/* END of source modifications */
]===========================================])
add_executable(sdl_issue main.c)
target_link_libraries(sdl_issue PRIVATE SDL3::SDL3)
# target_link_libraries(sdl_issue PRIVATE SDL3::SDL3-shared)
# target_link_libraries(sdl_issue PRIVATE SDL3::SDL3-static)
```
# CMake
[www.cmake.org](https://www.cmake.org/)
The CMake build system is supported on the following platforms:
* FreeBSD
* Linux
* Microsoft Visual C
* MinGW and Msys
* macOS, iOS, and tvOS, with support for XCode
* Android
* Emscripten
* FreeBSD
* Haiku
* Nintendo 3DS
* Playstation 2
* Playstation Vita
* QNX 7.x/8.x
* RiscOS
## Building SDL
Assuming the source tree of SDL is located at `~/sdl`,
this will configure and build SDL in the `~/build` directory:
```sh
cmake -S ~/sdl -B ~/build
cmake --build ~/build
```
Installation can be done using:
```sh
cmake --install ~/build --prefix /usr/local # '--install' requires CMake 3.15, or newer
```
This will install SDL to /usr/local.
### Building SDL tests
You can build the SDL test programs by adding `-DSDL_TESTS=ON` to the first cmake command above:
```sh
cmake -S ~/sdl -B ~/build -DSDL_TEST_LIBRARY=ON -DSDL_TESTS=ON
```
and then building normally. In this example, the test programs will be built and can be run from `~/build/tests/`.
## Including SDL in your project
SDL can be included in your project in 2 major ways:
- using a system SDL library, provided by your (*nix) distribution or a package manager
- using a vendored SDL library: this is SDL copied or symlinked in a subfolder.
The following CMake script supports both, depending on the value of `MYGAME_VENDORED`.
```cmake
cmake_minimum_required(VERSION 3.5)
project(mygame)
# Create an option to switch between a system sdl library and a vendored SDL library
option(MYGAME_VENDORED "Use vendored libraries" OFF)
if(MYGAME_VENDORED)
# This assumes you have added SDL as a submodule in vendored/SDL
add_subdirectory(vendored/SDL EXCLUDE_FROM_ALL)
else()
# 1. Look for a SDL3 package,
# 2. look for the SDL3-shared component, and
# 3. fail if the shared component cannot be found.
find_package(SDL3 REQUIRED CONFIG REQUIRED COMPONENTS SDL3-shared)
endif()
# Create your game executable target as usual
add_executable(mygame WIN32 mygame.c)
# Link to the actual SDL3 library.
target_link_libraries(mygame PRIVATE SDL3::SDL3)
```
### A system SDL library
For CMake to find SDL, it must be installed in [a default location CMake is looking for](https://cmake.org/cmake/help/latest/command/find_package.html#config-mode-search-procedure).
The following components are available, to be used as an argument of `find_package`.
| Component name | Description |
|----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| SDL3-shared | The SDL3 shared library, available through the `SDL3::SDL3-shared` target |
| SDL3-static | The SDL3 static library, available through the `SDL3::SDL3-static` target |
| SDL3_test | The SDL3_test static library, available through the `SDL3::SDL3_test` target |
| SDL3 | The SDL3 library, available through the `SDL3::SDL3` target. This is an alias of `SDL3::SDL3-shared` or `SDL3::SDL3-static`. This component is always available. |
| Headers | The SDL3 headers, available through the `SDL3::Headers` target. This component is always available. |
### Using a vendored SDL
This only requires a copy of SDL in a subdirectory + `add_subdirectory`.
Alternatively, use [FetchContent](https://cmake.org/cmake/help/latest/module/FetchContent.html).
Depending on the configuration, the same targets as a system SDL package are available.
## CMake configuration options
### Build optimized library
By default, CMake provides 4 build types: `Debug`, `Release`, `RelWithDebInfo` and `MinSizeRel`.
The main difference(s) between these are the optimization options and the generation of debug info.
To configure SDL as an optimized `Release` library, configure SDL with:
```sh
cmake ~/SDL -DCMAKE_BUILD_TYPE=Release
```
To build it, run:
```sh
cmake --build . --config Release
```
### Shared or static
By default, only a shared SDL library is built and installed.
The options `-DSDL_SHARED=` and `-DSDL_STATIC=` accept boolean values to change this.
### Pass custom compile options to the compiler
- Use [`CMAKE_<LANG>_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_LANG_FLAGS.html) to pass extra
flags to the compiler.
- Use [`CMAKE_EXE_LINKER_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_EXE_LINKER_FLAGS.html) to pass extra option to the linker for executables.
- Use [`CMAKE_SHARED_LINKER_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_SHARED_LINKER_FLAGS.html) to pass extra options to the linker for shared libraries.
#### Examples
- build a SDL library optimized for (more) modern x64 microprocessor architectures.
With gcc or clang:
```sh
cmake ~/sdl -DCMAKE_C_FLAGS="-march=x86-64-v3" -DCMAKE_CXX_FLAGS="-march=x86-64-v3"
```
With Visual C:
```sh
cmake .. -DCMAKE_C_FLAGS="/ARCH:AVX2" -DCMAKE_CXX_FLAGS="/ARCH:AVX2"
```
### iOS/tvOS
CMake 3.14+ natively includes support for iOS and tvOS. SDL binaries may be built
using Xcode or Make, possibly among other build-systems.
When using a recent version of CMake (3.14+), it should be possible to:
- build SDL for iOS, both static and dynamic
- build SDL test apps (as iOS/tvOS .app bundles)
- generate a working SDL_build_config.h for iOS (using SDL_build_config.h.cmake as a basis)
To use, set the following CMake variables when running CMake's configuration stage:
- `CMAKE_SYSTEM_NAME=<OS>` (either `iOS` or `tvOS`)
- `CMAKE_OSX_SYSROOT=<SDK>` (examples: `iphoneos`, `iphonesimulator`, `iphoneos12.4`, `/full/path/to/iPhoneOS.sdk`,
`appletvos`, `appletvsimulator`, `appletvos12.4`, `/full/path/to/AppleTVOS.sdk`, etc.)
- `CMAKE_OSX_ARCHITECTURES=<semicolon-separated list of CPU architectures>` (example: "arm64;armv7s;x86_64")
#### Examples
- for iOS-Simulator, using the latest, installed SDK:
```bash
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64
```
- for iOS-Device, using the latest, installed SDK, 64-bit only
```bash
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES=arm64
```
- for iOS-Device, using the latest, installed SDK, mixed 32/64 bit
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES="arm64;armv7s"
```
- for iOS-Device, using a specific SDK revision (iOS 12.4, in this example):
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos12.4 -DCMAKE_OSX_ARCHITECTURES=arm64
```
- for iOS-Simulator, using the latest, installed SDK, and building SDL test apps (as .app bundles):
```cmake
cmake ~/sdl -DSDL_TESTS=1 -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64
```
- for tvOS-Simulator, using the latest, installed SDK:
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=tvOS -DCMAKE_OSX_SYSROOT=appletvsimulator -DCMAKE_OSX_ARCHITECTURES=x86_64
```
- for tvOS-Device, using the latest, installed SDK:
```cmake
cmake ~/sdl -DCMAKE_SYSTEM_NAME=tvOS -DCMAKE_OSX_SYSROOT=appletvos -DCMAKE_OSX_ARCHITECTURES=arm64`
```
- for QNX/aarch64, using the latest, installed SDK:
```cmake
cmake ~/sdl -DCMAKE_TOOLCHAIN_FILE=~/sdl/build-scripts/cmake-toolchain-qnx-aarch64le.cmake -DSDL_X11=0
```
## SDL-specific CMake options
SDL can be customized through (platform-specific) CMake options.
The following table shows generic options that are available for most platforms.
At the end of SDL CMake configuration, a table shows all CMake options along with its detected value.
| CMake option | Valid values | Description |
|-------------------------------|--------------|-----------------------------------------------------------------------------------------------------|
| `-DSDL_SHARED=` | `ON`/`OFF` | Build SDL shared library (not all platforms support this) (`libSDL3.so`/`libSDL3.dylib`/`SDL3.dll`) |
| `-DSDL_STATIC=` | `ON`/`OFF` | Build SDL static library (`libSDL3.a`/`SDL3-static.lib`) |
| `-DSDL_TEST_LIBRARY=` | `ON`/`OFF` | Build SDL test library (`libSDL3_test.a`/`SDL3_test.lib`) |
| `-DSDL_TESTS=` | `ON`/`OFF` | Build SDL test programs (**requires `-DSDL_TEST_LIBRARY=ON`**) |
| `-DSDL_DISABLE_INSTALL=` | `ON`/`OFF` | Don't create a SDL install target |
| `-DSDL_DISABLE_INSTALL_DOCS=` | `ON`/`OFF` | Don't install the SDL documentation |
| `-DSDL_INSTALL_TESTS=` | `ON`/`OFF` | Install the SDL test programs |
## Help, it doesn't work!
Below, a SDL3 CMake project can be found that builds 99.9% of time (assuming you have internet connectivity).
When you have a problem with building or using SDL, please modify it until it reproduces your issue.
```cmake
cmake_minimum_required(VERSION 3.16)
project(sdl_issue)
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# !!!!!! !!!!!!
# !!!!!! This CMake script is not using "CMake best practices". !!!!!!
# !!!!!! Don't use it in your project. !!!!!!
# !!!!!! !!!!!!
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# 1. Try system SDL3 package first
find_package(SDL3 QUIET)
if(SDL3_FOUND)
message(STATUS "Using SDL3 via find_package")
endif()
# 2. Try using a vendored SDL library
if(NOT SDL3_FOUND AND EXISTS "${CMAKE_CURRENT_LIST_DIR}/SDL/CMakeLists.txt")
add_subdirectory(SDL)
message(STATUS "Using SDL3 via add_subdirectory")
set(SDL3_FOUND TRUE)
endif()
# 3. Download SDL, and use that.
if(NOT SDL3_FOUND)
include(FetchContent)
set(SDL_SHARED TRUE CACHE BOOL "Build a SDL shared library (if available)")
set(SDL_STATIC TRUE CACHE BOOL "Build a SDL static library (if available)")
FetchContent_Declare(
SDL
GIT_REPOSITORY https://github.com/libsdl-org/SDL.git
GIT_TAG main # Replace this with a particular git tag or git hash
GIT_SHALLOW TRUE
GIT_PROGRESS TRUE
)
message(STATUS "Using SDL3 via FetchContent")
FetchContent_MakeAvailable(SDL)
set_property(DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/_deps/sdl-src" PROPERTY EXCLUDE_FROM_ALL TRUE)
endif()
file(WRITE main.c [===========================================[
/**
* Modify this source such that it reproduces your problem.
*/
/* START of source modifications */
#include <SDL3/SDL.h>
int main(int argc, char *argv[]) {
if (SDL_Init(SDL_INIT_EVERYTHING) < 0) {
SDL_Log("SDL_Init failed (%s)", SDL_GetError());
return 1;
}
SDL_Window *window = NULL;
SDL_Renderer *renderer = NULL;
if (SDL_CreateWindowAndRenderer(640, 480, 0, &window, &renderer) < 0) {
SDL_Log("SDL_CreateWindowAndRenderer failed (%s)", SDL_GetError());
SDL_Quit();
return 1;
}
SDL_SetWindowTitle(window, "SDL issue");
while (1) {
int finished = 0;
SDL_Event event;
while (SDL_PollEvent(&event)) {
if (event.type == SDL_EVENT_QUIT) {
finished = 1;
break;
}
}
if (finished) {
break;
}
SDL_SetRenderDrawColor(renderer, 80, 80, 80, SDL_ALPHA_OPAQUE);
SDL_RenderClear(renderer);
SDL_RenderPresent(renderer);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
}
/* END of source modifications */
]===========================================])
add_executable(sdl_issue main.c)
target_link_libraries(sdl_issue PRIVATE SDL3::SDL3)
# target_link_libraries(sdl_issue PRIVATE SDL3::SDL3-shared)
# target_link_libraries(sdl_issue PRIVATE SDL3::SDL3-static)
```

194
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View File

@ -1,97 +1,97 @@
# Contributing to SDL
We appreciate your interest in contributing to SDL, this document will describe how to report bugs, contribute code or ideas or edit documentation.
**Table Of Contents**
- [Filing a GitHub issue](#filing-a-github-issue)
- [Reporting a bug](#reporting-a-bug)
- [Suggesting enhancements](#suggesting-enhancements)
- [Contributing code](#contributing-code)
- [Forking the project](#forking-the-project)
- [Following the style guide](#following-the-style-guide)
- [Running the tests](#running-the-tests)
- [Opening a pull request](#opening-a-pull-request)
- [Contributing to the documentation](#contributing-to-the-documentation)
- [Editing a function documentation](#editing-a-function-documentation)
- [Editing the wiki](#editing-the-wiki)
## Filing a GitHub issue
### Reporting a bug
If you think you have found a bug and would like to report it, here are the steps you should take:
- Before opening a new issue, ensure your bug has not already been reported on the [GitHub Issues page](https://github.com/libsdl-org/SDL/issues).
- On the issue tracker, click on [New Issue](https://github.com/libsdl-org/SDL/issues/new).
- Include details about your environment, such as your Operating System and SDL version.
- If possible, provide a small example that reproduces your bug.
### Suggesting enhancements
If you want to suggest changes for the project, here are the steps you should take:
- Check if the suggestion has already been made on:
- the [issue tracker](https://github.com/libsdl-org/SDL/issues);
- the [discourse forum](https://discourse.libsdl.org/);
- or if a [pull request](https://github.com/libsdl-org/SDL/pulls) already exists.
- On the issue tracker, click on [New Issue](https://github.com/libsdl-org/SDL/issues/new).
- Describe what change you would like to happen.
## Contributing code
This section will cover how the process of forking the project, making a change and opening a pull request.
### Forking the project
The first step consists in making a fork of the project, this is only necessary for the first contribution.
Head over to https://github.com/libsdl-org/SDL and click on the `Fork` button in the top right corner of your screen, you may leave the fields unchanged and click `Create Fork`.
You will be redirected to your fork of the repository, click the green `Code` button and copy the git clone link.
If you had already forked the repository, you may update it from the web page using the `Fetch upstream` button.
### Following the style guide
Code formatting is done using a custom `.clang-format` file, you can learn more about how to run it [here](https://clang.llvm.org/docs/ClangFormat.html).
Some legacy code may not be formatted, as such avoid formatting the whole file at once and only format around your changes.
For your commit message to be properly displayed on GitHub, it should contain:
- A short description of the commit of 50 characters or less on the first line.
- If necessary, add a blank line followed by a long description, each line should be 72 characters or less.
For example:
```
Fix crash in SDL_FooBar.
This addresses the issue #123456 by making sure Foo was successful
before calling Bar.
```
### Running the tests
Tests allow you to verify if your changes did not break any behaviour, here are the steps to follow:
- Before pushing, run the `testautomation` suite on your machine, there should be no more failing tests after your change than before.
- After pushing to your fork, Continuous Integration (GitHub Actions) will ensure compilation and tests still pass on other systems.
### Opening a pull request
- Head over to your fork's GitHub page.
- Click on the `Contribute` button and `Open Pull Request`.
- Fill out the pull request template.
- If any changes are requested, you can add new commits to your fork and they will be automatically added to the pull request.
## Contributing to the documentation
### Editing a function documentation
The wiki documentation for API functions is synchronised from the headers' doxygen comments. As such, all modifications to syntax; function parameters; return value; version; related functions should be done in the header directly.
### Editing the wiki
Other changes to the wiki should done directly from https://wiki.libsdl.org/ ... Just click the "edit" link at the bottom of any page!
# Contributing to SDL
We appreciate your interest in contributing to SDL, this document will describe how to report bugs, contribute code or ideas or edit documentation.
**Table Of Contents**
- [Filing a GitHub issue](#filing-a-github-issue)
- [Reporting a bug](#reporting-a-bug)
- [Suggesting enhancements](#suggesting-enhancements)
- [Contributing code](#contributing-code)
- [Forking the project](#forking-the-project)
- [Following the style guide](#following-the-style-guide)
- [Running the tests](#running-the-tests)
- [Opening a pull request](#opening-a-pull-request)
- [Contributing to the documentation](#contributing-to-the-documentation)
- [Editing a function documentation](#editing-a-function-documentation)
- [Editing the wiki](#editing-the-wiki)
## Filing a GitHub issue
### Reporting a bug
If you think you have found a bug and would like to report it, here are the steps you should take:
- Before opening a new issue, ensure your bug has not already been reported on the [GitHub Issues page](https://github.com/libsdl-org/SDL/issues).
- On the issue tracker, click on [New Issue](https://github.com/libsdl-org/SDL/issues/new).
- Include details about your environment, such as your Operating System and SDL version.
- If possible, provide a small example that reproduces your bug.
### Suggesting enhancements
If you want to suggest changes for the project, here are the steps you should take:
- Check if the suggestion has already been made on:
- the [issue tracker](https://github.com/libsdl-org/SDL/issues);
- the [discourse forum](https://discourse.libsdl.org/);
- or if a [pull request](https://github.com/libsdl-org/SDL/pulls) already exists.
- On the issue tracker, click on [New Issue](https://github.com/libsdl-org/SDL/issues/new).
- Describe what change you would like to happen.
## Contributing code
This section will cover how the process of forking the project, making a change and opening a pull request.
### Forking the project
The first step consists in making a fork of the project, this is only necessary for the first contribution.
Head over to https://github.com/libsdl-org/SDL and click on the `Fork` button in the top right corner of your screen, you may leave the fields unchanged and click `Create Fork`.
You will be redirected to your fork of the repository, click the green `Code` button and copy the git clone link.
If you had already forked the repository, you may update it from the web page using the `Fetch upstream` button.
### Following the style guide
Code formatting is done using a custom `.clang-format` file, you can learn more about how to run it [here](https://clang.llvm.org/docs/ClangFormat.html).
Some legacy code may not be formatted, as such avoid formatting the whole file at once and only format around your changes.
For your commit message to be properly displayed on GitHub, it should contain:
- A short description of the commit of 50 characters or less on the first line.
- If necessary, add a blank line followed by a long description, each line should be 72 characters or less.
For example:
```
Fix crash in SDL_FooBar.
This addresses the issue #123456 by making sure Foo was successful
before calling Bar.
```
### Running the tests
Tests allow you to verify if your changes did not break any behaviour, here are the steps to follow:
- Before pushing, run the `testautomation` suite on your machine, there should be no more failing tests after your change than before.
- After pushing to your fork, Continuous Integration (GitHub Actions) will ensure compilation and tests still pass on other systems.
### Opening a pull request
- Head over to your fork's GitHub page.
- Click on the `Contribute` button and `Open Pull Request`.
- Fill out the pull request template.
- If any changes are requested, you can add new commits to your fork and they will be automatically added to the pull request.
## Contributing to the documentation
### Editing a function documentation
The wiki documentation for API functions is synchronised from the headers' doxygen comments. As such, all modifications to syntax; function parameters; return value; version; related functions should be done in the header directly.
### Editing the wiki
Other changes to the wiki should done directly from https://wiki.libsdl.org/ ... Just click the "edit" link at the bottom of any page!

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@ -1,138 +1,138 @@
# Dynamic API
Originally posted on Ryan's Google+ account.
Background:
- The Steam Runtime has (at least in theory) a really kick-ass build of SDL,
but developers are shipping their own SDL with individual Steam games.
These games might stop getting updates, but a newer SDL might be needed later.
Certainly we'll always be fixing bugs in SDL, even if a new video target isn't
ever needed, and these fixes won't make it to a game shipping its own SDL.
- Even if we replace the SDL in those games with a compatible one, that is to
say, edit a developer's Steam depot (yuck!), there are developers that are
statically linking SDL that we can't do this for. We can't even force the
dynamic loader to ignore their SDL in this case, of course.
- If you don't ship an SDL with the game in some form, people that disabled the
Steam Runtime, or just tried to run the game from the command line instead of
Steam might find themselves unable to run the game, due to a missing dependency.
- If you want to ship on non-Steam platforms like GOG or Humble Bundle, or target
generic Linux boxes that may or may not have SDL installed, you have to ship
the library or risk a total failure to launch. So now, you might have to have
a non-Steam build plus a Steam build (that is, one with and one without SDL
included), which is inconvenient if you could have had one universal build
that works everywhere.
- We like the zlib license, but the biggest complaint from the open source
community about the license change is the static linking. The LGPL forced this
as a legal, not technical issue, but zlib doesn't care. Even those that aren't
concerned about the GNU freedoms found themselves solving the same problems:
swapping in a newer SDL to an older game often times can save the day.
Static linking stops this dead.
So here's what we did:
SDL now has, internally, a table of function pointers. So, this is what SDL_Init
now looks like:
```c
UInt32 SDL_Init(Uint32 flags)
{
return jump_table.SDL_Init(flags);
}
```
Except that is all done with a bunch of macro magic so we don't have to maintain
every one of these.
What is jump_table.SDL_init()? Eventually, that's a function pointer of the real
SDL_Init() that you've been calling all this time. But at startup, it looks more
like this:
```c
Uint32 SDL_Init_DEFAULT(Uint32 flags)
{
SDL_InitDynamicAPI();
return jump_table.SDL_Init(flags);
}
```
SDL_InitDynamicAPI() fills in jump_table with all the actual SDL function
pointers, which means that this `_DEFAULT` function never gets called again.
First call to any SDL function sets the whole thing up.
So you might be asking, what was the value in that? Isn't this what the operating
system's dynamic loader was supposed to do for us? Yes, but now we've got this
level of indirection, we can do things like this:
```bash
export SDL3_DYNAMIC_API=/my/actual/libSDL3.so.0
./MyGameThatIsStaticallyLinkedToSDL
```
And now, this game that is statically linked to SDL, can still be overridden
with a newer, or better, SDL. The statically linked one will only be used as
far as calling into the jump table in this case. But in cases where no override
is desired, the statically linked version will provide its own jump table,
and everyone is happy.
So now:
- Developers can statically link SDL, and users can still replace it.
(We'd still rather you ship a shared library, though!)
- Developers can ship an SDL with their game, Valve can override it for, say,
new features on SteamOS, or distros can override it for their own needs,
but it'll also just work in the default case.
- Developers can ship the same package to everyone (Humble Bundle, GOG, etc),
and it'll do the right thing.
- End users (and Valve) can update a game's SDL in almost any case,
to keep abandoned games running on newer platforms.
- Everyone develops with SDL exactly as they have been doing all along.
Same headers, same ABI. Just get the latest version to enable this magic.
A little more about SDL_InitDynamicAPI():
Internally, InitAPI does some locking to make sure everything waits until a
single thread initializes everything (although even SDL_CreateThread() goes
through here before spinning a thread, too), and then decides if it should use
an external SDL library. If not, it sets up the jump table using the current
SDL's function pointers (which might be statically linked into a program, or in
a shared library of its own). If so, it loads that library and looks for and
calls a single function:
```c
SInt32 SDL_DYNAPI_entry(Uint32 version, void *table, Uint32 tablesize);
```
That function takes a version number (more on that in a moment), the address of
the jump table, and the size, in bytes, of the table.
Now, we've got policy here: this table's layout never changes; new stuff gets
added to the end. Therefore SDL_DYNAPI_entry() knows that it can provide all
the needed functions if tablesize <= sizeof its own jump table. If tablesize is
bigger (say, SDL 3.0.4 is trying to load SDL 3.0.3), then we know to abort, but
if it's smaller, we know we can provide the entire API that the caller needs.
The version variable is a failsafe switch.
Right now it's always 1. This number changes when there are major API changes
(so we know if the tablesize might be smaller, or entries in it have changed).
Right now SDL_DYNAPI_entry gives up if the version doesn't match, but it's not
inconceivable to have a small dispatch library that only supplies this one
function and loads different, otherwise-incompatible SDL libraries and has the
right one initialize the jump table based on the version. For something that
must generically catch lots of different versions of SDL over time, like the
Steam Client, this isn't a bad option.
Finally, I'm sure some people are reading this and thinking,
"I don't want that overhead in my project!"
To which I would point out that the extra function call through the jump table
probably wouldn't even show up in a profile, but lucky you: this can all be
disabled. You can build SDL without this if you absolutely must, but we would
encourage you not to do that. However, on heavily locked down platforms like
iOS, or maybe when debugging, it makes sense to disable it. The way this is
designed in SDL, you just have to change one #define, and the entire system
vaporizes out, and SDL functions exactly like it always did. Most of it is
macro magic, so the system is contained to one C file and a few headers.
However, this is on by default and you have to edit a header file to turn it
off. Our hopes is that if we make it easy to disable, but not too easy,
everyone will ultimately be able to get what they want, but we've gently
nudged everyone towards what we think is the best solution.
# Dynamic API
Originally posted on Ryan's Google+ account.
Background:
- The Steam Runtime has (at least in theory) a really kick-ass build of SDL,
but developers are shipping their own SDL with individual Steam games.
These games might stop getting updates, but a newer SDL might be needed later.
Certainly we'll always be fixing bugs in SDL, even if a new video target isn't
ever needed, and these fixes won't make it to a game shipping its own SDL.
- Even if we replace the SDL in those games with a compatible one, that is to
say, edit a developer's Steam depot (yuck!), there are developers that are
statically linking SDL that we can't do this for. We can't even force the
dynamic loader to ignore their SDL in this case, of course.
- If you don't ship an SDL with the game in some form, people that disabled the
Steam Runtime, or just tried to run the game from the command line instead of
Steam might find themselves unable to run the game, due to a missing dependency.
- If you want to ship on non-Steam platforms like GOG or Humble Bundle, or target
generic Linux boxes that may or may not have SDL installed, you have to ship
the library or risk a total failure to launch. So now, you might have to have
a non-Steam build plus a Steam build (that is, one with and one without SDL
included), which is inconvenient if you could have had one universal build
that works everywhere.
- We like the zlib license, but the biggest complaint from the open source
community about the license change is the static linking. The LGPL forced this
as a legal, not technical issue, but zlib doesn't care. Even those that aren't
concerned about the GNU freedoms found themselves solving the same problems:
swapping in a newer SDL to an older game often times can save the day.
Static linking stops this dead.
So here's what we did:
SDL now has, internally, a table of function pointers. So, this is what SDL_Init
now looks like:
```c
UInt32 SDL_Init(Uint32 flags)
{
return jump_table.SDL_Init(flags);
}
```
Except that is all done with a bunch of macro magic so we don't have to maintain
every one of these.
What is jump_table.SDL_init()? Eventually, that's a function pointer of the real
SDL_Init() that you've been calling all this time. But at startup, it looks more
like this:
```c
Uint32 SDL_Init_DEFAULT(Uint32 flags)
{
SDL_InitDynamicAPI();
return jump_table.SDL_Init(flags);
}
```
SDL_InitDynamicAPI() fills in jump_table with all the actual SDL function
pointers, which means that this `_DEFAULT` function never gets called again.
First call to any SDL function sets the whole thing up.
So you might be asking, what was the value in that? Isn't this what the operating
system's dynamic loader was supposed to do for us? Yes, but now we've got this
level of indirection, we can do things like this:
```bash
export SDL3_DYNAMIC_API=/my/actual/libSDL3.so.0
./MyGameThatIsStaticallyLinkedToSDL
```
And now, this game that is statically linked to SDL, can still be overridden
with a newer, or better, SDL. The statically linked one will only be used as
far as calling into the jump table in this case. But in cases where no override
is desired, the statically linked version will provide its own jump table,
and everyone is happy.
So now:
- Developers can statically link SDL, and users can still replace it.
(We'd still rather you ship a shared library, though!)
- Developers can ship an SDL with their game, Valve can override it for, say,
new features on SteamOS, or distros can override it for their own needs,
but it'll also just work in the default case.
- Developers can ship the same package to everyone (Humble Bundle, GOG, etc),
and it'll do the right thing.
- End users (and Valve) can update a game's SDL in almost any case,
to keep abandoned games running on newer platforms.
- Everyone develops with SDL exactly as they have been doing all along.
Same headers, same ABI. Just get the latest version to enable this magic.
A little more about SDL_InitDynamicAPI():
Internally, InitAPI does some locking to make sure everything waits until a
single thread initializes everything (although even SDL_CreateThread() goes
through here before spinning a thread, too), and then decides if it should use
an external SDL library. If not, it sets up the jump table using the current
SDL's function pointers (which might be statically linked into a program, or in
a shared library of its own). If so, it loads that library and looks for and
calls a single function:
```c
SInt32 SDL_DYNAPI_entry(Uint32 version, void *table, Uint32 tablesize);
```
That function takes a version number (more on that in a moment), the address of
the jump table, and the size, in bytes, of the table.
Now, we've got policy here: this table's layout never changes; new stuff gets
added to the end. Therefore SDL_DYNAPI_entry() knows that it can provide all
the needed functions if tablesize <= sizeof its own jump table. If tablesize is
bigger (say, SDL 3.0.4 is trying to load SDL 3.0.3), then we know to abort, but
if it's smaller, we know we can provide the entire API that the caller needs.
The version variable is a failsafe switch.
Right now it's always 1. This number changes when there are major API changes
(so we know if the tablesize might be smaller, or entries in it have changed).
Right now SDL_DYNAPI_entry gives up if the version doesn't match, but it's not
inconceivable to have a small dispatch library that only supplies this one
function and loads different, otherwise-incompatible SDL libraries and has the
right one initialize the jump table based on the version. For something that
must generically catch lots of different versions of SDL over time, like the
Steam Client, this isn't a bad option.
Finally, I'm sure some people are reading this and thinking,
"I don't want that overhead in my project!"
To which I would point out that the extra function call through the jump table
probably wouldn't even show up in a profile, but lucky you: this can all be
disabled. You can build SDL without this if you absolutely must, but we would
encourage you not to do that. However, on heavily locked down platforms like
iOS, or maybe when debugging, it makes sense to disable it. The way this is
designed in SDL, you just have to change one #define, and the entire system
vaporizes out, and SDL functions exactly like it always did. Most of it is
macro magic, so the system is contained to one C file and a few headers.
However, this is on by default and you have to edit a header file to turn it
off. Our hopes is that if we make it easy to disable, but not too easy,
everyone will ultimately be able to get what they want, but we've gently
nudged everyone towards what we think is the best solution.

730
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View File

@ -1,365 +1,365 @@
# Emscripten
## The state of things
(As of September 2023, but things move quickly and we don't update this
document often.)
In modern times, all the browsers you probably care about (Chrome, Firefox,
Edge, and Safari, on Windows, macOS, Linux, iOS and Android), support some
reasonable base configurations:
- WebAssembly (don't bother with asm.js any more)
- WebGL (which will look like OpenGL ES 2 or 3 to your app).
- Threads (see caveats, though!)
- Game controllers
- Autoupdating (so you can assume they have a recent version of the browser)
All this to say we're at the point where you don't have to make a lot of
concessions to get even a fairly complex SDL-based game up and running.
## RTFM
This document is a quick rundown of some high-level details. The
documentation at [emscripten.org](https://emscripten.org/) is vast
and extremely detailed for a wide variety of topics, and you should at
least skim through it at some point.
## Porting your app to Emscripten
Many many things just need some simple adjustments and they'll compile
like any other C/C++ code, as long as SDL was handling the platform-specific
work for your program.
First, you probably need this in at least one of your source files:
```c
#ifdef __EMSCRIPTEN__
#include <emscripten.h>
#endif
```
Second: assembly language code has to go. Replace it with C. You can even use
[x86 SIMD intrinsic functions in Emscripten](https://emscripten.org/docs/porting/simd.html)!
Third: Middleware has to go. If you have a third-party library you link
against, you either need an Emscripten port of it, or the source code to it
to compile yourself, or you need to remove it.
Fourth: You still start in a function called main(), but you need to get out of
it and into a function that gets called repeatedly, and returns quickly,
called a mainloop.
Somewhere in your program, you probably have something that looks like a more
complicated version of this:
```c
void main(void)
{
initialize_the_game();
while (game_is_still_running) {
check_for_new_input();
think_about_stuff();
draw_the_next_frame();
}
deinitialize_the_game();
}
```
This will not work on Emscripten, because the main thread needs to be free
to do stuff and can't sit in this loop forever. So Emscripten lets you set up
a [mainloop](https://emscripten.org/docs/porting/emscripten-runtime-environment.html#browser-main-loop).
```c
static void mainloop(void) /* this will run often, possibly at the monitor's refresh rate */
{
if (!game_is_still_running) {
deinitialize_the_game();
#ifdef __EMSCRIPTEN__
emscripten_cancel_main_loop(); /* this should "kill" the app. */
#else
exit(0);
#endif
}
check_for_new_input();
think_about_stuff();
draw_the_next_frame();
}
void main(void)
{
initialize_the_game();
#ifdef __EMSCRIPTEN__
emscripten_set_main_loop(mainloop, 0, 1);
#else
while (1) { mainloop(); }
#endif
}
```
Basically, `emscripten_set_main_loop(mainloop, 0, 1);` says "run
`mainloop` over and over until I end the program." The function will
run, and return, freeing the main thread for other tasks, and then
run again when it's time. The `1` parameter does some magic to make
your main() function end immediately; this is useful because you
don't want any shutdown code that might be sitting below this code
to actually run if main() were to continue on, since we're just
getting started.
There's a lot of little details that are beyond the scope of this
document, but that's the biggest intial set of hurdles to porting
your app to the web.
## Do you need threads?
If you plan to use threads, they work on all major browsers now. HOWEVER,
they bring with them a lot of careful considerations. Rendering _must_
be done on the main thread. This is a general guideline for many
platforms, but a hard requirement on the web.
Many other things also must happen on the main thread; often times SDL
and Emscripten make efforts to "proxy" work to the main thread that
must be there, but you have to be careful (and read more detailed
documentation than this for the finer points).
Even when using threads, your main thread needs to set an Emscripten
mainloop that runs quickly and returns, or things will fail to work
correctly.
You should definitely read [Emscripten's pthreads docs](https://emscripten.org/docs/porting/pthreads.html)
for all the finer points. Mostly SDL's thread API will work as expected,
but is built on pthreads, so it shares the same little incompatibilities
that are documented there, such as where you can use a mutex, and when
a thread will start running, etc.
IMPORTANT: You have to decide to either build something that uses
threads or something that doesn't; you can't have one build
that works everywhere. This is an Emscripten (or maybe WebAssembly?
Or just web browsers in general?) limitation. If you aren't using
threads, it's easier to not enable them at all, at build time.
If you use threads, you _have to_ run from a web server that has
[COOP/COEP headers set correctly](https://web.dev/why-coop-coep/)
or your program will fail to start at all.
If building with threads, `__EMSCRIPTEN_PTHREADS__` will be defined
for checking with the C preprocessor, so you can build something
different depending on what sort of build you're compiling.
## Audio
Audio works as expected at the API level, but not exactly like other
platforms.
You'll only see a single default audio device. Audio capture also works;
if the browser pops up a prompt to ask for permission to access the
microphone, the SDL_OpenAudioDevice call will succeed and start producing
silence at a regular interval. Once the user approves the request, real
audio data will flow. If the user denies it, the app is not informed and
will just continue to receive silence.
Modern web browsers will not permit web pages to produce sound before the
user has interacted with them (clicked or tapped on them, usually); this is
for several reasons, not the least of which being that no one likes when a
random browser tab suddenly starts making noise and the user has to scramble
to figure out which and silence it.
SDL will allow you to open the audio device for playback in this
circumstance, and your audio callback will fire, but SDL will throw the audio
data away until the user interacts with the page. This helps apps that depend
on the audio callback to make progress, and also keeps audio playback in sync
once the app is finally allowed to make noise.
There are two reasonable ways to deal with the silence at the app level:
if you are writing some sort of media player thing, where the user expects
there to be a volume control when you mouseover the canvas, just default
that control to a muted state; if the user clicks on the control to unmute
it, on this first click, open the audio device. This allows the media to
play at start, and the user can reasonably opt-in to listening.
Many games do not have this sort of UI, and are more rigid about starting
audio along with everything else at the start of the process. For these, your
best bet is to write a little Javascript that puts up a "Click here to play!"
UI, and upon the user clicking, remove that UI and then call the Emscripten
app's main() function. As far as the application knows, the audio device was
available to be opened as soon as the program started, and since this magic
happens in a little Javascript, you don't have to change your C/C++ code at
all to make it happen.
Please see the discussion at https://github.com/libsdl-org/SDL/issues/6385
for some Javascript code to steal for this approach.
## Rendering
If you use SDL's 2D render API, it will use GLES2 internally, which
Emscripten will turn into WebGL calls. You can also use OpenGL ES 2
directly by creating a GL context and drawing into it.
Calling SDL_RenderPresent (or SDL_GL_SwapWindow) will not actually
present anything on the screen until your return from your mainloop
function.
## Building SDL/emscripten
First: do you _really_ need to build SDL from source?
If you aren't developing SDL itself, have a desire to mess with its source
code, or need something on the bleeding edge, don't build SDL. Just use
Emscripten's packaged version!
Compile and link your app with `-sUSE_SDL=2` and it'll use a build of
SDL packaged with Emscripten. This comes from the same source code and
fixes the Emscripten project makes to SDL are generally merged into SDL's
revision control, so often this is much easier for app developers.
`-sUSE_SDL=1` will select Emscripten's JavaScript reimplementation of SDL
1.2 instead; if you need SDL 1.2, this might be fine, but we generally
recommend you don't use SDL 1.2 in modern times.
If you want to build SDL, though...
SDL currently requires at least Emscripten 3.1.35 to build. Newer versions
are likely to work, as well.
Build:
This works on Linux/Unix and macOS. Please send comments about Windows.
Make sure you've [installed emsdk](https://emscripten.org/docs/getting_started/downloads.html)
first, and run `source emsdk_env.sh` at the command line so it finds the
tools.
(These cmake options might be overkill, but this has worked for me.)
```bash
mkdir build
cd build
emcmake cmake ..
# you can also do `emcmake cmake -G Ninja ..` and then use `ninja` instead of this command.
emmake make -j4
```
If you want to build with thread support, something like this works:
```bash
mkdir build
cd build
emcmake cmake -DSDL_THREADS=On ..
# you can also do `emcmake cmake -G Ninja ..` and then use `ninja` instead of this command.
emmake make -j4
```
To build the tests, add `-DSDL_TESTS=On` to the `emcmake cmake` command line.
## Building your app
You need to compile with `emcc` instead of `gcc` or `clang` or whatever, but
mostly it uses the same command line arguments as Clang.
Link against the SDL/build/libSDL3.a file you generated by building SDL,
link with `-sUSE_SDL=2` to use Emscripten's prepackaged SDL2 build.
Usually you would produce a binary like this:
```bash
gcc -o mygame mygame.c # or whatever
```
But for Emscripten, you want to output something else:
```bash
emcc -o index.html mygame.c
```
This will produce several files...support Javascript and WebAssembly (.wasm)
files. The `-o index.html` will produce a simple HTML page that loads and
runs your app. You will (probably) eventually want to replace or customize
that file and do `-o index.js` instead to just build the code pieces.
If you're working on a program of any serious size, you'll likely need to
link with `-sALLOW_MEMORY_GROWTH=1 -sMAXIMUM_MEMORY=1gb` to get access
to more memory. If using pthreads, you'll need the `-sMAXIMUM_MEMORY=1gb`
or the app will fail to start on iOS browsers, but this might be a bug that
goes away in the future.
## Data files
Your game probably has data files. Here's how to access them.
Filesystem access works like a Unix filesystem; you have a single directory
tree, possibly interpolated from several mounted locations, no drive letters,
'/' for a path separator. You can access them with standard file APIs like
open() or fopen() or SDL_RWops. You can read or write from the filesystem.
By default, you probably have a "MEMFS" filesystem (all files are stored in
memory, but access to them is immediate and doesn't need to block). There are
other options, like "IDBFS" (files are stored in a local database, so they
don't need to be in RAM all the time and they can persist between runs of the
program, but access is not synchronous). You can mix and match these file
systems, mounting a MEMFS filesystem at one place and idbfs elsewhere, etc,
but that's beyond the scope of this document. Please refer to Emscripten's
[page on the topic](https://emscripten.org/docs/porting/files/file_systems_overview.html)
for more info.
The _easiest_ (but not the best) way to get at your data files is to embed
them in the app itself. Emscripten's linker has support for automating this.
```bash
emcc -o index.html loopwave.c --embed-file=../test/sample.wav@/sounds/sample.wav
```
This will pack ../test/sample.wav in your app, and make it available at
"/sounds/sample.wav" at runtime. Emscripten makes sure this data is available
before your main() function runs, and since it's in MEMFS, you can just
read it like you do on other platforms. `--embed-file` can also accept a
directory to pack an entire tree, and you can specify the argument multiple
times to pack unrelated things into the final installation.
Note that this is absolutely the best approach if you have a few small
files to include and shouldn't worry about the issue further. However, if you
have hundreds of megabytes and/or thousands of files, this is not so great,
since the user will download it all every time they load your page, and it
all has to live in memory at runtime.
[Emscripten's documentation on the matter](https://emscripten.org/docs/porting/files/packaging_files.html)
gives other options and details, and is worth a read.
## Debugging
Debugging web apps is a mixed bag. You should compile and link with
`-gsource-map`, which embeds a ton of source-level debugging information into
the build, and make sure _the app source code is available on the web server_,
which is often a scary proposition for various reasons.
When you debug from the browser's tools and hit a breakpoint, you can step
through the actual C/C++ source code, though, which can be nice.
If you try debugging in Firefox and it doesn't work well for no apparent
reason, try Chrome, and vice-versa. These tools are still relatively new,
and improving all the time.
SDL_Log() (or even plain old printf) will write to the Javascript console,
and honestly I find printf-style debugging to be easier than setting up a build
for proper debugging, so use whatever tools work best for you.
## Questions?
Please give us feedback on this document at [the SDL bug tracker](https://github.com/libsdl-org/SDL/issues).
If something is wrong or unclear, we want to know!
# Emscripten
## The state of things
(As of September 2023, but things move quickly and we don't update this
document often.)
In modern times, all the browsers you probably care about (Chrome, Firefox,
Edge, and Safari, on Windows, macOS, Linux, iOS and Android), support some
reasonable base configurations:
- WebAssembly (don't bother with asm.js any more)
- WebGL (which will look like OpenGL ES 2 or 3 to your app).
- Threads (see caveats, though!)
- Game controllers
- Autoupdating (so you can assume they have a recent version of the browser)
All this to say we're at the point where you don't have to make a lot of
concessions to get even a fairly complex SDL-based game up and running.
## RTFM
This document is a quick rundown of some high-level details. The
documentation at [emscripten.org](https://emscripten.org/) is vast
and extremely detailed for a wide variety of topics, and you should at
least skim through it at some point.
## Porting your app to Emscripten
Many many things just need some simple adjustments and they'll compile
like any other C/C++ code, as long as SDL was handling the platform-specific
work for your program.
First, you probably need this in at least one of your source files:
```c
#ifdef __EMSCRIPTEN__
#include <emscripten.h>
#endif
```
Second: assembly language code has to go. Replace it with C. You can even use
[x86 SIMD intrinsic functions in Emscripten](https://emscripten.org/docs/porting/simd.html)!
Third: Middleware has to go. If you have a third-party library you link
against, you either need an Emscripten port of it, or the source code to it
to compile yourself, or you need to remove it.
Fourth: You still start in a function called main(), but you need to get out of
it and into a function that gets called repeatedly, and returns quickly,
called a mainloop.
Somewhere in your program, you probably have something that looks like a more
complicated version of this:
```c
void main(void)
{
initialize_the_game();
while (game_is_still_running) {
check_for_new_input();
think_about_stuff();
draw_the_next_frame();
}
deinitialize_the_game();
}
```
This will not work on Emscripten, because the main thread needs to be free
to do stuff and can't sit in this loop forever. So Emscripten lets you set up
a [mainloop](https://emscripten.org/docs/porting/emscripten-runtime-environment.html#browser-main-loop).
```c
static void mainloop(void) /* this will run often, possibly at the monitor's refresh rate */
{
if (!game_is_still_running) {
deinitialize_the_game();
#ifdef __EMSCRIPTEN__
emscripten_cancel_main_loop(); /* this should "kill" the app. */
#else
exit(0);
#endif
}
check_for_new_input();
think_about_stuff();
draw_the_next_frame();
}
void main(void)
{
initialize_the_game();
#ifdef __EMSCRIPTEN__
emscripten_set_main_loop(mainloop, 0, 1);
#else
while (1) { mainloop(); }
#endif
}
```
Basically, `emscripten_set_main_loop(mainloop, 0, 1);` says "run
`mainloop` over and over until I end the program." The function will
run, and return, freeing the main thread for other tasks, and then
run again when it's time. The `1` parameter does some magic to make
your main() function end immediately; this is useful because you
don't want any shutdown code that might be sitting below this code
to actually run if main() were to continue on, since we're just
getting started.
There's a lot of little details that are beyond the scope of this
document, but that's the biggest intial set of hurdles to porting
your app to the web.
## Do you need threads?
If you plan to use threads, they work on all major browsers now. HOWEVER,
they bring with them a lot of careful considerations. Rendering _must_
be done on the main thread. This is a general guideline for many
platforms, but a hard requirement on the web.
Many other things also must happen on the main thread; often times SDL
and Emscripten make efforts to "proxy" work to the main thread that
must be there, but you have to be careful (and read more detailed
documentation than this for the finer points).
Even when using threads, your main thread needs to set an Emscripten
mainloop that runs quickly and returns, or things will fail to work
correctly.
You should definitely read [Emscripten's pthreads docs](https://emscripten.org/docs/porting/pthreads.html)
for all the finer points. Mostly SDL's thread API will work as expected,
but is built on pthreads, so it shares the same little incompatibilities
that are documented there, such as where you can use a mutex, and when
a thread will start running, etc.
IMPORTANT: You have to decide to either build something that uses
threads or something that doesn't; you can't have one build
that works everywhere. This is an Emscripten (or maybe WebAssembly?
Or just web browsers in general?) limitation. If you aren't using
threads, it's easier to not enable them at all, at build time.
If you use threads, you _have to_ run from a web server that has
[COOP/COEP headers set correctly](https://web.dev/why-coop-coep/)
or your program will fail to start at all.
If building with threads, `__EMSCRIPTEN_PTHREADS__` will be defined
for checking with the C preprocessor, so you can build something
different depending on what sort of build you're compiling.
## Audio
Audio works as expected at the API level, but not exactly like other
platforms.
You'll only see a single default audio device. Audio capture also works;
if the browser pops up a prompt to ask for permission to access the
microphone, the SDL_OpenAudioDevice call will succeed and start producing
silence at a regular interval. Once the user approves the request, real
audio data will flow. If the user denies it, the app is not informed and
will just continue to receive silence.
Modern web browsers will not permit web pages to produce sound before the
user has interacted with them (clicked or tapped on them, usually); this is
for several reasons, not the least of which being that no one likes when a
random browser tab suddenly starts making noise and the user has to scramble
to figure out which and silence it.
SDL will allow you to open the audio device for playback in this
circumstance, and your audio callback will fire, but SDL will throw the audio
data away until the user interacts with the page. This helps apps that depend
on the audio callback to make progress, and also keeps audio playback in sync
once the app is finally allowed to make noise.
There are two reasonable ways to deal with the silence at the app level:
if you are writing some sort of media player thing, where the user expects
there to be a volume control when you mouseover the canvas, just default
that control to a muted state; if the user clicks on the control to unmute
it, on this first click, open the audio device. This allows the media to
play at start, and the user can reasonably opt-in to listening.
Many games do not have this sort of UI, and are more rigid about starting
audio along with everything else at the start of the process. For these, your
best bet is to write a little Javascript that puts up a "Click here to play!"
UI, and upon the user clicking, remove that UI and then call the Emscripten
app's main() function. As far as the application knows, the audio device was
available to be opened as soon as the program started, and since this magic
happens in a little Javascript, you don't have to change your C/C++ code at
all to make it happen.
Please see the discussion at https://github.com/libsdl-org/SDL/issues/6385
for some Javascript code to steal for this approach.
## Rendering
If you use SDL's 2D render API, it will use GLES2 internally, which
Emscripten will turn into WebGL calls. You can also use OpenGL ES 2
directly by creating a GL context and drawing into it.
Calling SDL_RenderPresent (or SDL_GL_SwapWindow) will not actually
present anything on the screen until your return from your mainloop
function.
## Building SDL/emscripten
First: do you _really_ need to build SDL from source?
If you aren't developing SDL itself, have a desire to mess with its source
code, or need something on the bleeding edge, don't build SDL. Just use
Emscripten's packaged version!
Compile and link your app with `-sUSE_SDL=2` and it'll use a build of
SDL packaged with Emscripten. This comes from the same source code and
fixes the Emscripten project makes to SDL are generally merged into SDL's
revision control, so often this is much easier for app developers.
`-sUSE_SDL=1` will select Emscripten's JavaScript reimplementation of SDL
1.2 instead; if you need SDL 1.2, this might be fine, but we generally
recommend you don't use SDL 1.2 in modern times.
If you want to build SDL, though...
SDL currently requires at least Emscripten 3.1.35 to build. Newer versions
are likely to work, as well.
Build:
This works on Linux/Unix and macOS. Please send comments about Windows.
Make sure you've [installed emsdk](https://emscripten.org/docs/getting_started/downloads.html)
first, and run `source emsdk_env.sh` at the command line so it finds the
tools.
(These cmake options might be overkill, but this has worked for me.)
```bash
mkdir build
cd build
emcmake cmake ..
# you can also do `emcmake cmake -G Ninja ..` and then use `ninja` instead of this command.
emmake make -j4
```
If you want to build with thread support, something like this works:
```bash
mkdir build
cd build
emcmake cmake -DSDL_THREADS=On ..
# you can also do `emcmake cmake -G Ninja ..` and then use `ninja` instead of this command.
emmake make -j4
```
To build the tests, add `-DSDL_TESTS=On` to the `emcmake cmake` command line.
## Building your app
You need to compile with `emcc` instead of `gcc` or `clang` or whatever, but
mostly it uses the same command line arguments as Clang.
Link against the SDL/build/libSDL3.a file you generated by building SDL,
link with `-sUSE_SDL=2` to use Emscripten's prepackaged SDL2 build.
Usually you would produce a binary like this:
```bash
gcc -o mygame mygame.c # or whatever
```
But for Emscripten, you want to output something else:
```bash
emcc -o index.html mygame.c
```
This will produce several files...support Javascript and WebAssembly (.wasm)
files. The `-o index.html` will produce a simple HTML page that loads and
runs your app. You will (probably) eventually want to replace or customize
that file and do `-o index.js` instead to just build the code pieces.
If you're working on a program of any serious size, you'll likely need to
link with `-sALLOW_MEMORY_GROWTH=1 -sMAXIMUM_MEMORY=1gb` to get access
to more memory. If using pthreads, you'll need the `-sMAXIMUM_MEMORY=1gb`
or the app will fail to start on iOS browsers, but this might be a bug that
goes away in the future.
## Data files
Your game probably has data files. Here's how to access them.
Filesystem access works like a Unix filesystem; you have a single directory
tree, possibly interpolated from several mounted locations, no drive letters,
'/' for a path separator. You can access them with standard file APIs like
open() or fopen() or SDL_RWops. You can read or write from the filesystem.
By default, you probably have a "MEMFS" filesystem (all files are stored in
memory, but access to them is immediate and doesn't need to block). There are
other options, like "IDBFS" (files are stored in a local database, so they
don't need to be in RAM all the time and they can persist between runs of the
program, but access is not synchronous). You can mix and match these file
systems, mounting a MEMFS filesystem at one place and idbfs elsewhere, etc,
but that's beyond the scope of this document. Please refer to Emscripten's
[page on the topic](https://emscripten.org/docs/porting/files/file_systems_overview.html)
for more info.
The _easiest_ (but not the best) way to get at your data files is to embed
them in the app itself. Emscripten's linker has support for automating this.
```bash
emcc -o index.html loopwave.c --embed-file=../test/sample.wav@/sounds/sample.wav
```
This will pack ../test/sample.wav in your app, and make it available at
"/sounds/sample.wav" at runtime. Emscripten makes sure this data is available
before your main() function runs, and since it's in MEMFS, you can just
read it like you do on other platforms. `--embed-file` can also accept a
directory to pack an entire tree, and you can specify the argument multiple
times to pack unrelated things into the final installation.
Note that this is absolutely the best approach if you have a few small
files to include and shouldn't worry about the issue further. However, if you
have hundreds of megabytes and/or thousands of files, this is not so great,
since the user will download it all every time they load your page, and it
all has to live in memory at runtime.
[Emscripten's documentation on the matter](https://emscripten.org/docs/porting/files/packaging_files.html)
gives other options and details, and is worth a read.
## Debugging
Debugging web apps is a mixed bag. You should compile and link with
`-gsource-map`, which embeds a ton of source-level debugging information into
the build, and make sure _the app source code is available on the web server_,
which is often a scary proposition for various reasons.
When you debug from the browser's tools and hit a breakpoint, you can step
through the actual C/C++ source code, though, which can be nice.
If you try debugging in Firefox and it doesn't work well for no apparent
reason, try Chrome, and vice-versa. These tools are still relatively new,
and improving all the time.
SDL_Log() (or even plain old printf) will write to the Javascript console,
and honestly I find printf-style debugging to be easier than setting up a build
for proper debugging, so use whatever tools work best for you.
## Questions?
Please give us feedback on this document at [the SDL bug tracker](https://github.com/libsdl-org/SDL/issues).
If something is wrong or unclear, we want to know!

318
docs/README-gdk.md
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@ -1,159 +1,159 @@
GDK
=====
This port allows SDL applications to run via Microsoft's Game Development Kit (GDK).
Windows (GDK) and Xbox One/Xbox Series (GDKX) are supported. Although most of the Xbox code is included in the public SDL source code, NDA access is required for a small number of source files. If you have access to GDKX, these required Xbox files are posted on the GDK forums [here](https://forums.xboxlive.com/questions/130003/).
Requirements
------------
* Microsoft Visual Studio 2022 (in theory, it should also work in 2017 or 2019, but this has not been tested)
* Microsoft GDK June 2022 or newer (public release [here](https://github.com/microsoft/GDK/releases/tag/June_2022))
* To publish a package or successfully authenticate a user, you will need to create an app id/configure services in Partner Center. However, for local testing purposes (without authenticating on Xbox Live), the identifiers used by the GDK test programs in the included solution will work.
Windows GDK Status
------
The Windows GDK port supports the full set of Win32 APIs, renderers, controllers, input devices, etc., as the normal Windows x64 build of SDL.
* Additionally, the GDK port adds the following:
* Compile-time platform detection for SDL programs. The `__GDK__` is `#define`d on every GDK platform, and the `__WINGDK__` is `#define`d on Windows GDK, specifically. (This distinction exists because other GDK platforms support a smaller subset of functionality. This allows you to mark code for "any" GDK separate from Windows GDK.)
* GDK-specific setup:
* Initializing/uninitializing the game runtime, and initializing Xbox Live services
* Creating a global task queue and setting it as the default for the process. When running any async operations, passing in `NULL` as the task queue will make the task get added to the global task queue.
* An implementation on `WinMain` that performs the above GDK setup that you can use by #include'ing SDL_main.h in the source file that includes your standard main() function. If you are unable to do this, you can instead manually call `SDL_RunApp` from your entry point, passing in your `SDL_main` function and `NULL` as the parameters. To use `SDL_RunApp`, `#define SDL_MAIN_HANDLED` before `#include <SDL3/SDL_main.h>`.
* Global task queue callbacks are dispatched during `SDL_PumpEvents` (which is also called internally if using `SDL_PollEvent`).
* You can get the handle of the global task queue through `SDL_GDKGetTaskQueue`, if needed. When done with the queue, be sure to use `XTaskQueueCloseHandle` to decrement the reference count (otherwise it will cause a resource leak).
* Single-player games have some additional features available:
* Call `SDL_GDKGetDefaultUser` to get the default XUserHandle pointer.
* `SDL_GetPrefPath` still works, but only for single-player titles.
These functions mostly wrap around async APIs, and thus should be treated as synchronous alternatives. Also note that the single-player functions return on any OS errors, so be sure to validate the return values!
* What doesn't work:
* Compilation with anything other than through the included Visual C++ solution file
## VisualC-GDK Solution
The included `VisualC-GDK/SDL.sln` solution includes the following targets for the Gaming.Desktop.x64 configuration:
* SDL3 (DLL) - This is the typical SDL3.dll, but for Gaming.Desktop.x64.
* tests/testgamecontroller - Standard SDL test program demonstrating controller functionality.
* tests/testgdk - GDK-specific test program that demonstrates using the global task queue to login a user into Xbox Live.
*NOTE*: As of the June 2022 GDK, you cannot test user logins without a valid Title ID and MSAAppId. You will need to manually change the identifiers in the `MicrosoftGame.config` to your valid IDs from Partner Center if you wish to test this.
* tests/testsprite - Standard SDL test program demonstrating sprite drawing functionality.
If you set one of the test programs as a startup project, you can run it directly from Visual Studio.
Windows GDK Setup, Detailed Steps
---------------------
These steps assume you already have a game using SDL that runs on Windows x64 along with a corresponding Visual Studio solution file for the x64 version. If you don't have this, it's easiest to use one of the test program vcxproj files in the `VisualC-GDK` directory as a starting point, though you will still need to do most of the steps below.
### 1. Add a Gaming.Desktop.x64 Configuration ###
In your game's existing Visual Studio Solution, go to Build > Configuration Manager. From the "Active solution platform" drop-down select "New...". From the drop-down list, select Gaming.Desktop.x64 and copy the settings from the x64 configuration.
### 2. Build SDL3 for GDK ###
Open `VisualC-GDK/SDL.sln` in Visual Studio, you need to build the SDL3 target for the Gaming.Desktop.x64 platform (Release is recommended). You will need to copy/keep track of the `SDL3.dll`, `XCurl.dll` (which is output by Gaming.Desktop.x64), and `SDL3.lib` output files for your game project.
*Alternatively*, you could setup your solution file to instead reference the SDL3 project file targets from the SDL source, and add those projects as a dependency. This would mean that SDL3 would be built when your game is built.
### 3. Configuring Project Settings ###
While the Gaming.Desktop.x64 configuration sets most of the required settings, there are some additional items to configure for your game project under the Gaming.Desktop.x64 Configuration:
* Under C/C++ > General > Additional Include Directories, make sure the `SDL/include` path is referenced
* Under Linker > General > Additional Library Directories, make sure to reference the path where the newly-built SDL3.lib are
* Under Linker > Input > Additional Dependencies, you need the following:
* `SDL3.lib`
* `xgameruntime.lib`
* `../Microsoft.Xbox.Services.141.GDK.C.Thunks.lib`
* Note that in general, the GDK libraries depend on the MSVC C/C++ runtime, so there is no way to remove this dependency from a GDK program that links against GDK.
### 4. Setting up SDL_main ###
Rather than using your own implementation of `WinMain`, it's recommended that you instead `#include <SDL3/SDL_main.h>` and declare a standard main function. If you are unable to do this, you can instead manually call `SDL_RunApp` from your entry point, passing in your `SDL_main` function and `NULL` as the parameters; in that case `#define SDL_MAIN_HANDLED` before including SDL_main.h
### 5. Required DLLs ###
The game will not launch in the debugger unless required DLLs are included in the directory that contains the game's .exe file. You need to make sure that the following files are copied into the directory:
* Your SDL3.dll
* "$(Console_GRDKExtLibRoot)Xbox.Services.API.C\DesignTime\CommonConfiguration\Neutral\Lib\Release\Microsoft.Xbox.Services.141.GDK.C.Thunks.dll"
* XCurl.dll
You can either copy these in a post-build step, or you can add the dlls into the project and set its Configuration Properties > General > Item type to "Copy file," which will also copy them into the output directory.
### 6. Setting up MicrosoftGame.config ###
You can copy `VisualC-GDK/tests/testgdk/MicrosoftGame.config` and use that as a starting point in your project. Minimally, you will want to change the Executable Name attribute, the DefaultDisplayName, and the Description.
This file must be copied into the same directory as the game's .exe file. As with the DLLs, you can either use a post-build step or the "Copy file" item type.
For basic testing, you do not need to change anything else in `MicrosoftGame.config`. However, if you want to test any Xbox Live services (such as logging in users) _or_ publish a package, you will need to setup a Game app on Partner Center.
Then, you need to set the following values to the values from Partner Center:
* Identity tag - Name and Publisher attributes
* TitleId
* MSAAppId
### 7. Adding Required Logos
Several logo PNG files are required to be able to launch the game, even from the debugger. You can use the sample logos provided in `VisualC-GDK/logos`. As with the other files, they must be copied into the same directory as the game's .exe file.
### 8. Copying any Data Files ###
When debugging GDK games, there is no way to specify a working directory. Therefore, any required game data must also be copied into the output directory, likely in a post-build step.
### 9. Build and Run from Visual Studio ###
At this point, you should be able to build and run your game from the Visual Studio Debugger. If you get any linker errors, make sure you double-check that you referenced all the required libs.
If you are testing Xbox Live functionality, it's likely you will need to change to the Sandbox for your title. To do this:
1. Run "Desktop VS 2022 Gaming Command Prompt" from the Start Menu
2. Switch the sandbox name with:
`XblPCSandbox SANDBOX.#`
3. (To switch back to the retail sandbox):
`XblPCSandbox RETAIL`
### 10. Packaging and Installing Locally
You can use one of the test program's `PackageLayout.xml` as a starting point. Minimally, you will need to change the exe to the correct name and also reference any required game data. As with the other data files, it's easiest if you have this copy to the output directory, although it's not a requirement as you can specify relative paths to files.
To create the package:
1. Run "Desktop VS 2022 Gaming Command Prompt" from the Start Menu
2. `cd` to the directory containing the `PackageLayout.xml` with the correct paths (if you use the local path as in the sample package layout, this would be from your .exe output directory)
3. `mkdir Package` to create an output directory
4. To package the file into the `Package` directory, use:
`makepkg pack /f PackageLayout.xml /lt /d . /nogameos /pc /pd Package`
5. To install the package, use:
`wdapp install PACKAGENAME.msixvc`
6. Once the package is installed, you can run it from the start menu.
7. As with when running from Visual Studio, if you need to test any Xbox Live functionality you must switch to the correct sandbox.
Troubleshooting
---------------
#### Xbox Live Login does not work
As of June 2022 GDK, you must have a valid Title Id and MSAAppId in order to test Xbox Live functionality such as user login. Make sure these are set correctly in the `MicrosoftGame.config`. This means that even testgdk will not let you login without setting these properties to valid values.
Furthermore, confirm that your PC is set to the correct sandbox.
#### "The current user has already installed an unpackaged version of this app. A packaged version cannot replace this." error when installing
Prior to June 2022 GDK, running from the Visual Studio debugger would still locally register the app (and it would appear on the start menu). To fix this, you have to uninstall it (it's simplest to right click on it from the start menu to uninstall it).
GDK
=====
This port allows SDL applications to run via Microsoft's Game Development Kit (GDK).
Windows (GDK) and Xbox One/Xbox Series (GDKX) are supported. Although most of the Xbox code is included in the public SDL source code, NDA access is required for a small number of source files. If you have access to GDKX, these required Xbox files are posted on the GDK forums [here](https://forums.xboxlive.com/questions/130003/).
Requirements
------------
* Microsoft Visual Studio 2022 (in theory, it should also work in 2017 or 2019, but this has not been tested)
* Microsoft GDK June 2022 or newer (public release [here](https://github.com/microsoft/GDK/releases/tag/June_2022))
* To publish a package or successfully authenticate a user, you will need to create an app id/configure services in Partner Center. However, for local testing purposes (without authenticating on Xbox Live), the identifiers used by the GDK test programs in the included solution will work.
Windows GDK Status
------
The Windows GDK port supports the full set of Win32 APIs, renderers, controllers, input devices, etc., as the normal Windows x64 build of SDL.
* Additionally, the GDK port adds the following:
* Compile-time platform detection for SDL programs. The `__GDK__` is `#define`d on every GDK platform, and the `__WINGDK__` is `#define`d on Windows GDK, specifically. (This distinction exists because other GDK platforms support a smaller subset of functionality. This allows you to mark code for "any" GDK separate from Windows GDK.)
* GDK-specific setup:
* Initializing/uninitializing the game runtime, and initializing Xbox Live services
* Creating a global task queue and setting it as the default for the process. When running any async operations, passing in `NULL` as the task queue will make the task get added to the global task queue.
* An implementation on `WinMain` that performs the above GDK setup that you can use by #include'ing SDL_main.h in the source file that includes your standard main() function. If you are unable to do this, you can instead manually call `SDL_RunApp` from your entry point, passing in your `SDL_main` function and `NULL` as the parameters. To use `SDL_RunApp`, `#define SDL_MAIN_HANDLED` before `#include <SDL3/SDL_main.h>`.
* Global task queue callbacks are dispatched during `SDL_PumpEvents` (which is also called internally if using `SDL_PollEvent`).
* You can get the handle of the global task queue through `SDL_GDKGetTaskQueue`, if needed. When done with the queue, be sure to use `XTaskQueueCloseHandle` to decrement the reference count (otherwise it will cause a resource leak).
* Single-player games have some additional features available:
* Call `SDL_GDKGetDefaultUser` to get the default XUserHandle pointer.
* `SDL_GetPrefPath` still works, but only for single-player titles.
These functions mostly wrap around async APIs, and thus should be treated as synchronous alternatives. Also note that the single-player functions return on any OS errors, so be sure to validate the return values!
* What doesn't work:
* Compilation with anything other than through the included Visual C++ solution file
## VisualC-GDK Solution
The included `VisualC-GDK/SDL.sln` solution includes the following targets for the Gaming.Desktop.x64 configuration:
* SDL3 (DLL) - This is the typical SDL3.dll, but for Gaming.Desktop.x64.
* tests/testgamecontroller - Standard SDL test program demonstrating controller functionality.
* tests/testgdk - GDK-specific test program that demonstrates using the global task queue to login a user into Xbox Live.
*NOTE*: As of the June 2022 GDK, you cannot test user logins without a valid Title ID and MSAAppId. You will need to manually change the identifiers in the `MicrosoftGame.config` to your valid IDs from Partner Center if you wish to test this.
* tests/testsprite - Standard SDL test program demonstrating sprite drawing functionality.
If you set one of the test programs as a startup project, you can run it directly from Visual Studio.
Windows GDK Setup, Detailed Steps
---------------------
These steps assume you already have a game using SDL that runs on Windows x64 along with a corresponding Visual Studio solution file for the x64 version. If you don't have this, it's easiest to use one of the test program vcxproj files in the `VisualC-GDK` directory as a starting point, though you will still need to do most of the steps below.
### 1. Add a Gaming.Desktop.x64 Configuration ###
In your game's existing Visual Studio Solution, go to Build > Configuration Manager. From the "Active solution platform" drop-down select "New...". From the drop-down list, select Gaming.Desktop.x64 and copy the settings from the x64 configuration.
### 2. Build SDL3 for GDK ###
Open `VisualC-GDK/SDL.sln` in Visual Studio, you need to build the SDL3 target for the Gaming.Desktop.x64 platform (Release is recommended). You will need to copy/keep track of the `SDL3.dll`, `XCurl.dll` (which is output by Gaming.Desktop.x64), and `SDL3.lib` output files for your game project.
*Alternatively*, you could setup your solution file to instead reference the SDL3 project file targets from the SDL source, and add those projects as a dependency. This would mean that SDL3 would be built when your game is built.
### 3. Configuring Project Settings ###
While the Gaming.Desktop.x64 configuration sets most of the required settings, there are some additional items to configure for your game project under the Gaming.Desktop.x64 Configuration:
* Under C/C++ > General > Additional Include Directories, make sure the `SDL/include` path is referenced
* Under Linker > General > Additional Library Directories, make sure to reference the path where the newly-built SDL3.lib are
* Under Linker > Input > Additional Dependencies, you need the following:
* `SDL3.lib`
* `xgameruntime.lib`
* `../Microsoft.Xbox.Services.141.GDK.C.Thunks.lib`
* Note that in general, the GDK libraries depend on the MSVC C/C++ runtime, so there is no way to remove this dependency from a GDK program that links against GDK.
### 4. Setting up SDL_main ###
Rather than using your own implementation of `WinMain`, it's recommended that you instead `#include <SDL3/SDL_main.h>` and declare a standard main function. If you are unable to do this, you can instead manually call `SDL_RunApp` from your entry point, passing in your `SDL_main` function and `NULL` as the parameters; in that case `#define SDL_MAIN_HANDLED` before including SDL_main.h
### 5. Required DLLs ###
The game will not launch in the debugger unless required DLLs are included in the directory that contains the game's .exe file. You need to make sure that the following files are copied into the directory:
* Your SDL3.dll
* "$(Console_GRDKExtLibRoot)Xbox.Services.API.C\DesignTime\CommonConfiguration\Neutral\Lib\Release\Microsoft.Xbox.Services.141.GDK.C.Thunks.dll"
* XCurl.dll
You can either copy these in a post-build step, or you can add the dlls into the project and set its Configuration Properties > General > Item type to "Copy file," which will also copy them into the output directory.
### 6. Setting up MicrosoftGame.config ###
You can copy `VisualC-GDK/tests/testgdk/MicrosoftGame.config` and use that as a starting point in your project. Minimally, you will want to change the Executable Name attribute, the DefaultDisplayName, and the Description.
This file must be copied into the same directory as the game's .exe file. As with the DLLs, you can either use a post-build step or the "Copy file" item type.
For basic testing, you do not need to change anything else in `MicrosoftGame.config`. However, if you want to test any Xbox Live services (such as logging in users) _or_ publish a package, you will need to setup a Game app on Partner Center.
Then, you need to set the following values to the values from Partner Center:
* Identity tag - Name and Publisher attributes
* TitleId
* MSAAppId
### 7. Adding Required Logos
Several logo PNG files are required to be able to launch the game, even from the debugger. You can use the sample logos provided in `VisualC-GDK/logos`. As with the other files, they must be copied into the same directory as the game's .exe file.
### 8. Copying any Data Files ###
When debugging GDK games, there is no way to specify a working directory. Therefore, any required game data must also be copied into the output directory, likely in a post-build step.
### 9. Build and Run from Visual Studio ###
At this point, you should be able to build and run your game from the Visual Studio Debugger. If you get any linker errors, make sure you double-check that you referenced all the required libs.
If you are testing Xbox Live functionality, it's likely you will need to change to the Sandbox for your title. To do this:
1. Run "Desktop VS 2022 Gaming Command Prompt" from the Start Menu
2. Switch the sandbox name with:
`XblPCSandbox SANDBOX.#`
3. (To switch back to the retail sandbox):
`XblPCSandbox RETAIL`
### 10. Packaging and Installing Locally
You can use one of the test program's `PackageLayout.xml` as a starting point. Minimally, you will need to change the exe to the correct name and also reference any required game data. As with the other data files, it's easiest if you have this copy to the output directory, although it's not a requirement as you can specify relative paths to files.
To create the package:
1. Run "Desktop VS 2022 Gaming Command Prompt" from the Start Menu
2. `cd` to the directory containing the `PackageLayout.xml` with the correct paths (if you use the local path as in the sample package layout, this would be from your .exe output directory)
3. `mkdir Package` to create an output directory
4. To package the file into the `Package` directory, use:
`makepkg pack /f PackageLayout.xml /lt /d . /nogameos /pc /pd Package`
5. To install the package, use:
`wdapp install PACKAGENAME.msixvc`
6. Once the package is installed, you can run it from the start menu.
7. As with when running from Visual Studio, if you need to test any Xbox Live functionality you must switch to the correct sandbox.
Troubleshooting
---------------
#### Xbox Live Login does not work
As of June 2022 GDK, you must have a valid Title Id and MSAAppId in order to test Xbox Live functionality such as user login. Make sure these are set correctly in the `MicrosoftGame.config`. This means that even testgdk will not let you login without setting these properties to valid values.
Furthermore, confirm that your PC is set to the correct sandbox.
#### "The current user has already installed an unpackaged version of this app. A packaged version cannot replace this." error when installing
Prior to June 2022 GDK, running from the Visual Studio debugger would still locally register the app (and it would appear on the start menu). To fix this, you have to uninstall it (it's simplest to right click on it from the start menu to uninstall it).

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git
=========
The latest development version of SDL is available via git.
Git allows you to get up-to-the-minute fixes and enhancements;
as a developer works on a source tree, you can use "git" to mirror that
source tree instead of waiting for an official release. Please look
at the Git website ( https://git-scm.com/ ) for more
information on using git, where you can also download software for
macOS, Windows, and Unix systems.
git clone https://github.com/libsdl-org/SDL
If you are building SDL via configure, you will need to run autogen.sh
before running configure.
There is a web interface to the Git repository at:
http://github.com/libsdl-org/SDL/
git
=========
The latest development version of SDL is available via git.
Git allows you to get up-to-the-minute fixes and enhancements;
as a developer works on a source tree, you can use "git" to mirror that
source tree instead of waiting for an official release. Please look
at the Git website ( https://git-scm.com/ ) for more
information on using git, where you can also download software for
macOS, Windows, and Unix systems.
git clone https://github.com/libsdl-org/SDL
If you are building SDL via configure, you will need to run autogen.sh
before running configure.
There is a web interface to the Git repository at:
http://github.com/libsdl-org/SDL/

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Mercurial
======
We are no longer hosted in Mercurial. Please see README-git.md for details.
Thanks!
Mercurial
======
We are no longer hosted in Mercurial. Please see README-git.md for details.
Thanks!

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SDL 3.0 has new support for high DPI displays
Displays now have a content display scale, which is the expected scale for content based on the DPI settings of the display. For example, a 4K display might have a 2.0 (200%) display scale, which means that the user expects UI elements to be twice as big on this display, to aid in readability. You can query the display content scale using `SDL_GetDisplayContentScale()`, and when this changes you get an `SDL_EVENT_WINDOW_DISPLAY_SCALE_CHANGED` event.
The window size is now distinct from the window pixel size, and the ratio between the two is the window pixel density. If the window is created with the `SDL_WINDOW_HIGH_PIXEL_DENSITY` flag, SDL will try to match the native pixel density for the display, otherwise it will try to have the pixel size match the window size. You can query the window pixel density using `SDL_GetWindowPixelDensity()`. You can query the window pixel size using `SDL_GetWindowSizeInPixels()`, and when this changes you get an `SDL_EVENT_WINDOW_PIXEL_SIZE_CHANGED` event. You are guaranteed to get a `SDL_EVENT_WINDOW_PIXEL_SIZE_CHANGED` event when a window is created and resized, and you can use this event to create and resize your graphics context for the window.
The window has a display scale, which is the scale from the pixel resolution to the desired content size, e.g. the combination of the pixel density and the content scale. For example, a 3840x2160 window displayed at 200% on Windows, and a 1920x1080 window with the high density flag on a 2x display on macOS will both have a pixel size of 3840x2160 and a display scale of 2.0. You can query the window display scale using `SDL_GetWindowDisplayScale()`, and when this changes you get an `SDL_EVENT_WINDOW_DISPLAY_SCALE_CHANGED` event.
SDL 3.0 has new support for high DPI displays
Displays now have a content display scale, which is the expected scale for content based on the DPI settings of the display. For example, a 4K display might have a 2.0 (200%) display scale, which means that the user expects UI elements to be twice as big on this display, to aid in readability. You can query the display content scale using `SDL_GetDisplayContentScale()`, and when this changes you get an `SDL_EVENT_WINDOW_DISPLAY_SCALE_CHANGED` event.
The window size is now distinct from the window pixel size, and the ratio between the two is the window pixel density. If the window is created with the `SDL_WINDOW_HIGH_PIXEL_DENSITY` flag, SDL will try to match the native pixel density for the display, otherwise it will try to have the pixel size match the window size. You can query the window pixel density using `SDL_GetWindowPixelDensity()`. You can query the window pixel size using `SDL_GetWindowSizeInPixels()`, and when this changes you get an `SDL_EVENT_WINDOW_PIXEL_SIZE_CHANGED` event. You are guaranteed to get a `SDL_EVENT_WINDOW_PIXEL_SIZE_CHANGED` event when a window is created and resized, and you can use this event to create and resize your graphics context for the window.
The window has a display scale, which is the scale from the pixel resolution to the desired content size, e.g. the combination of the pixel density and the content scale. For example, a 3840x2160 window displayed at 200% on Windows, and a 1920x1080 window with the high density flag on a 2x display on macOS will both have a pixel size of 3840x2160 and a display scale of 2.0. You can query the window display scale using `SDL_GetWindowDisplayScale()`, and when this changes you get an `SDL_EVENT_WINDOW_DISPLAY_SCALE_CHANGED` event.

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iOS
======
Building the Simple DirectMedia Layer for iOS 9.0+
==============================================================================
Requirements: macOS 10.9 or later and the iOS 9.0 or newer SDK.
Instructions:
1. Open SDL.xcodeproj (located in Xcode/SDL) in Xcode.
2. Select your desired target, and hit build.
Using the Simple DirectMedia Layer for iOS
==============================================================================
1. Run Xcode and create a new project using the iOS Game template, selecting the Objective C language and Metal game technology.
2. In the main view, delete all files except for Assets and LaunchScreen
3. Right click the project in the main view, select "Add Files...", and add the SDL project, Xcode/SDL/SDL.xcodeproj
4. Select the project in the main view, go to the "Info" tab and under "Custom iOS Target Properties" remove the line "Main storyboard file base name"
5. Select the project in the main view, go to the "Build Settings" tab, select "All", and edit "Header Search Path" and drag over the SDL "Public Headers" folder from the left
6. Select the project in the main view, go to the "Build Phases" tab, select "Link Binary With Libraries", and add SDL3.framework from "Framework-iOS"
7. Select the project in the main view, go to the "General" tab, scroll down to "Frameworks, Libraries, and Embedded Content", and select "Embed & Sign" for the SDL library.
8. Add the source files that you would normally have for an SDL program, making sure to have #include "SDL.h" at the top of the file containing your main() function.
9. Add any assets that your application needs.
10. Enjoy!
TODO: Add information regarding App Store requirements such as icons, etc.
Notes -- Retina / High-DPI and window sizes
==============================================================================
Window and display mode sizes in SDL are in points rather than in pixels.
On iOS this means that a window created on an iPhone 6 will have a size in
points of 375 x 667, rather than a size in pixels of 750 x 1334. All iOS apps
are expected to size their content based on points rather than pixels,
as this allows different iOS devices to have different pixel densities
(Retina versus non-Retina screens, etc.) without apps caring too much.
SDL_GetWindowSize() and mouse coordinates are in points rather than pixels,
but the window will have a much greater pixel density when the device supports
it, and the SDL_GetWindowSizeInPixels() can be called to determine the size
in pixels of the drawable screen framebuffer.
The SDL 2D rendering API will automatically handle this for you, by default
providing a rendering area in points, and you can call SDL_SetRenderLogicalPresentation()
to gain access to the higher density resolution.
Some OpenGL ES functions such as glViewport expect sizes in pixels rather than
sizes in points. When doing 2D rendering with OpenGL ES, an orthographic projection
matrix using the size in points (SDL_GetWindowSize()) can be used in order to
display content at the same scale no matter whether a Retina device is used or not.
Notes -- Application events
==============================================================================
On iOS the application goes through a fixed life cycle and you will get
notifications of state changes via application events. When these events
are delivered you must handle them in an event callback because the OS may
not give you any processing time after the events are delivered.
e.g.
int HandleAppEvents(void *userdata, SDL_Event *event)
{
switch (event->type)
{
case SDL_EVENT_TERMINATING:
/* Terminate the app.
Shut everything down before returning from this function.
*/
return 0;
case SDL_EVENT_LOW_MEMORY:
/* You will get this when your app is paused and iOS wants more memory.
Release as much memory as possible.
*/
return 0;
case SDL_EVENT_WILL_ENTER_BACKGROUND:
/* Prepare your app to go into the background. Stop loops, etc.
This gets called when the user hits the home button, or gets a call.
*/
return 0;
case SDL_EVENT_DID_ENTER_BACKGROUND:
/* This will get called if the user accepted whatever sent your app to the background.
If the user got a phone call and canceled it, you'll instead get an SDL_EVENT_DID_ENTER_FOREGROUND event and restart your loops.
When you get this, you have 5 seconds to save all your state or the app will be terminated.
Your app is NOT active at this point.
*/
return 0;
case SDL_EVENT_WILL_ENTER_FOREGROUND:
/* This call happens when your app is coming back to the foreground.
Restore all your state here.
*/
return 0;
case SDL_EVENT_DID_ENTER_FOREGROUND:
/* Restart your loops here.
Your app is interactive and getting CPU again.
*/
return 0;
default:
/* No special processing, add it to the event queue */
return 1;
}
}
int main(int argc, char *argv[])
{
SDL_SetEventFilter(HandleAppEvents, NULL);
... run your main loop
return 0;
}
Notes -- Accelerometer as Joystick
==============================================================================
SDL for iPhone supports polling the built in accelerometer as a joystick device. For an example on how to do this, see the accelerometer.c in the demos directory.
The main thing to note when using the accelerometer with SDL is that while the iPhone natively reports accelerometer as floating point values in units of g-force, SDL_GetJoystickAxis() reports joystick values as signed integers. Hence, in order to convert between the two, some clamping and scaling is necessary on the part of the iPhone SDL joystick driver. To convert SDL_GetJoystickAxis() reported values BACK to units of g-force, simply multiply the values by SDL_IPHONE_MAX_GFORCE / 0x7FFF.
Notes -- Keyboard
==============================================================================
The SDL keyboard API has been extended to support on-screen keyboards:
void SDL_StartTextInput()
-- enables text events and reveals the onscreen keyboard.
void SDL_StopTextInput()
-- disables text events and hides the onscreen keyboard.
SDL_bool SDL_TextInputActive()
-- returns whether or not text events are enabled (and the onscreen keyboard is visible)
Notes -- Mouse
==============================================================================
iOS now supports Bluetooth mice on iPad, but by default will provide the mouse input as touch. In order for SDL to see the real mouse events, you should set the key UIApplicationSupportsIndirectInputEvents to true in your Info.plist
Notes -- Reading and Writing files
==============================================================================
Each application installed on iPhone resides in a sandbox which includes its own Application Home directory. Your application may not access files outside this directory.
Once your application is installed its directory tree looks like:
MySDLApp Home/
MySDLApp.app
Documents/
Library/
Preferences/
tmp/
When your SDL based iPhone application starts up, it sets the working directory to the main bundle (MySDLApp Home/MySDLApp.app), where your application resources are stored. You cannot write to this directory. Instead, I advise you to write document files to "../Documents/" and preferences to "../Library/Preferences".
More information on this subject is available here:
http://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/Introduction/Introduction.html
Notes -- xcFramework
==============================================================================
The SDL.xcodeproj file now includes a target to build SDL3.xcframework. An xcframework is a new (Xcode 11) uber-framework which can handle any combination of processor type and target OS platform.
In the past, iOS devices were always an ARM variant processor, and the simulator was always i386 or x86_64, and thus libraries could be combined into a single framework for both simulator and device. With the introduction of the Apple Silicon ARM-based machines, regular frameworks would collide as CPU type was no longer sufficient to differentiate the platform. So Apple created the new xcframework library package.
The xcframework target builds into a Products directory alongside the SDL.xcodeproj file, as SDL3.xcframework. This can be brought in to any iOS project and will function properly for both simulator and device, no matter their CPUs. Note that Intel Macs cannot cross-compile for Apple Silicon Macs. If you need AS compatibility, perform this build on an Apple Silicon Mac.
This target requires Xcode 11 or later. The target will simply fail to build if attempted on older Xcodes.
In addition, on Apple platforms, main() cannot be in a dynamically loaded library.
However, unlike in SDL2, in SDL3 SDL_main is implemented inline in SDL_main.h, so you don't need to link against a static libSDL3main.lib, and you don't need to copy a .c file from the SDL3 source either.
This means that iOS apps which used the statically-linked libSDL3.lib and now link with the xcframwork can just `#include <SDL3/SDL_main.h>` in the source file that contains their standard `int main(int argc; char *argv[])` function to get a header-only SDL_main implementation that calls the `SDL_RunApp()` with your standard main function.
Using an xcFramework is similar to using a regular framework. However, issues have been seen with the build system not seeing the headers in the xcFramework. To remedy this, add the path to the xcFramework in your app's target ==> Build Settings ==> Framework Search Paths and mark it recursive (this is critical). Also critical is to remove "*.framework" from Build Settings ==> Sub-Directories to Exclude in Recursive Searches. Clean the build folder, and on your next build the build system should be able to see any of these in your code, as expected:
#include "SDL_main.h"
#include <SDL.h>
#include <SDL_main.h>
Notes -- iPhone SDL limitations
==============================================================================
Windows:
Full-size, single window applications only. You cannot create multi-window SDL applications for iPhone OS. The application window will fill the display, though you have the option of turning on or off the menu-bar (pass SDL_CreateWindow() the flag SDL_WINDOW_BORDERLESS).
Textures:
The optimal texture formats on iOS are SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_XBGR8888, and SDL_PIXELFORMAT_RGB24 pixel formats.
Loading Shared Objects:
This is disabled by default since it seems to break the terms of the iOS SDK agreement for iOS versions prior to iOS 8. It can be re-enabled in SDL_config_ios.h.
Notes -- CoreBluetooth.framework
==============================================================================
SDL_JOYSTICK_HIDAPI is disabled by default. It can give you access to a lot
more game controller devices, but it requires permission from the user before
your app will be able to talk to the Bluetooth hardware. "Made For iOS"
branded controllers do not need this as we don't have to speak to them
directly with raw bluetooth, so many apps can live without this.
You'll need to link with CoreBluetooth.framework and add something like this
to your Info.plist:
<key>NSBluetoothPeripheralUsageDescription</key>
<string>MyApp would like to remain connected to nearby bluetooth Game Controllers and Game Pads even when you're not using the app.</string>
Game Center
==============================================================================
Game Center integration might require that you break up your main loop in order to yield control back to the system. In other words, instead of running an endless main loop, you run each frame in a callback function, using:
int SDL_iPhoneSetAnimationCallback(SDL_Window * window, int interval, void (*callback)(void*), void *callbackParam);
This will set up the given function to be called back on the animation callback, and then you have to return from main() to let the Cocoa event loop run.
e.g.
extern "C"
void ShowFrame(void*)
{
... do event handling, frame logic and rendering ...
}
int main(int argc, char *argv[])
{
... initialize game ...
#ifdef __IOS__
// Initialize the Game Center for scoring and matchmaking
InitGameCenter();
// Set up the game to run in the window animation callback on iOS
// so that Game Center and so forth works correctly.
SDL_iPhoneSetAnimationCallback(window, 1, ShowFrame, NULL);
#else
while ( running ) {
ShowFrame(0);
DelayFrame();
}
#endif
return 0;
}
Deploying to older versions of iOS
==============================================================================
SDL supports deploying to older versions of iOS than are supported by the latest version of Xcode, all the way back to iOS 8.0
In order to do that you need to download an older version of Xcode:
https://developer.apple.com/download/more/?name=Xcode
Open the package contents of the older Xcode and your newer version of Xcode and copy over the folders in Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport
Then open the file Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/SDKSettings.plist and add the versions of iOS you want to deploy to the key Root/DefaultProperties/DEPLOYMENT_TARGET_SUGGESTED_VALUES
Open your project and set your deployment target to the desired version of iOS
Finally, remove GameController from the list of frameworks linked by your application and edit the build settings for "Other Linker Flags" and add -weak_framework GameController
iOS
======
Building the Simple DirectMedia Layer for iOS 9.0+
==============================================================================
Requirements: macOS 10.9 or later and the iOS 9.0 or newer SDK.
Instructions:
1. Open SDL.xcodeproj (located in Xcode/SDL) in Xcode.
2. Select your desired target, and hit build.
Using the Simple DirectMedia Layer for iOS
==============================================================================
1. Run Xcode and create a new project using the iOS Game template, selecting the Objective C language and Metal game technology.
2. In the main view, delete all files except for Assets and LaunchScreen
3. Right click the project in the main view, select "Add Files...", and add the SDL project, Xcode/SDL/SDL.xcodeproj
4. Select the project in the main view, go to the "Info" tab and under "Custom iOS Target Properties" remove the line "Main storyboard file base name"
5. Select the project in the main view, go to the "Build Settings" tab, select "All", and edit "Header Search Path" and drag over the SDL "Public Headers" folder from the left
6. Select the project in the main view, go to the "Build Phases" tab, select "Link Binary With Libraries", and add SDL3.framework from "Framework-iOS"
7. Select the project in the main view, go to the "General" tab, scroll down to "Frameworks, Libraries, and Embedded Content", and select "Embed & Sign" for the SDL library.
8. Add the source files that you would normally have for an SDL program, making sure to have #include "SDL.h" at the top of the file containing your main() function.
9. Add any assets that your application needs.
10. Enjoy!
TODO: Add information regarding App Store requirements such as icons, etc.
Notes -- Retina / High-DPI and window sizes
==============================================================================
Window and display mode sizes in SDL are in points rather than in pixels.
On iOS this means that a window created on an iPhone 6 will have a size in
points of 375 x 667, rather than a size in pixels of 750 x 1334. All iOS apps
are expected to size their content based on points rather than pixels,
as this allows different iOS devices to have different pixel densities
(Retina versus non-Retina screens, etc.) without apps caring too much.
SDL_GetWindowSize() and mouse coordinates are in points rather than pixels,
but the window will have a much greater pixel density when the device supports
it, and the SDL_GetWindowSizeInPixels() can be called to determine the size
in pixels of the drawable screen framebuffer.
The SDL 2D rendering API will automatically handle this for you, by default
providing a rendering area in points, and you can call SDL_SetRenderLogicalPresentation()
to gain access to the higher density resolution.
Some OpenGL ES functions such as glViewport expect sizes in pixels rather than
sizes in points. When doing 2D rendering with OpenGL ES, an orthographic projection
matrix using the size in points (SDL_GetWindowSize()) can be used in order to
display content at the same scale no matter whether a Retina device is used or not.
Notes -- Application events
==============================================================================
On iOS the application goes through a fixed life cycle and you will get
notifications of state changes via application events. When these events
are delivered you must handle them in an event callback because the OS may
not give you any processing time after the events are delivered.
e.g.
int HandleAppEvents(void *userdata, SDL_Event *event)
{
switch (event->type)
{
case SDL_EVENT_TERMINATING:
/* Terminate the app.
Shut everything down before returning from this function.
*/
return 0;
case SDL_EVENT_LOW_MEMORY:
/* You will get this when your app is paused and iOS wants more memory.
Release as much memory as possible.
*/
return 0;
case SDL_EVENT_WILL_ENTER_BACKGROUND:
/* Prepare your app to go into the background. Stop loops, etc.
This gets called when the user hits the home button, or gets a call.
*/
return 0;
case SDL_EVENT_DID_ENTER_BACKGROUND:
/* This will get called if the user accepted whatever sent your app to the background.
If the user got a phone call and canceled it, you'll instead get an SDL_EVENT_DID_ENTER_FOREGROUND event and restart your loops.
When you get this, you have 5 seconds to save all your state or the app will be terminated.
Your app is NOT active at this point.
*/
return 0;
case SDL_EVENT_WILL_ENTER_FOREGROUND:
/* This call happens when your app is coming back to the foreground.
Restore all your state here.
*/
return 0;
case SDL_EVENT_DID_ENTER_FOREGROUND:
/* Restart your loops here.
Your app is interactive and getting CPU again.
*/
return 0;
default:
/* No special processing, add it to the event queue */
return 1;
}
}
int main(int argc, char *argv[])
{
SDL_SetEventFilter(HandleAppEvents, NULL);
... run your main loop
return 0;
}
Notes -- Accelerometer as Joystick
==============================================================================
SDL for iPhone supports polling the built in accelerometer as a joystick device. For an example on how to do this, see the accelerometer.c in the demos directory.
The main thing to note when using the accelerometer with SDL is that while the iPhone natively reports accelerometer as floating point values in units of g-force, SDL_GetJoystickAxis() reports joystick values as signed integers. Hence, in order to convert between the two, some clamping and scaling is necessary on the part of the iPhone SDL joystick driver. To convert SDL_GetJoystickAxis() reported values BACK to units of g-force, simply multiply the values by SDL_IPHONE_MAX_GFORCE / 0x7FFF.
Notes -- Keyboard
==============================================================================
The SDL keyboard API has been extended to support on-screen keyboards:
void SDL_StartTextInput()
-- enables text events and reveals the onscreen keyboard.
void SDL_StopTextInput()
-- disables text events and hides the onscreen keyboard.
SDL_bool SDL_TextInputActive()
-- returns whether or not text events are enabled (and the onscreen keyboard is visible)
Notes -- Mouse
==============================================================================
iOS now supports Bluetooth mice on iPad, but by default will provide the mouse input as touch. In order for SDL to see the real mouse events, you should set the key UIApplicationSupportsIndirectInputEvents to true in your Info.plist
Notes -- Reading and Writing files
==============================================================================
Each application installed on iPhone resides in a sandbox which includes its own Application Home directory. Your application may not access files outside this directory.
Once your application is installed its directory tree looks like:
MySDLApp Home/
MySDLApp.app
Documents/
Library/
Preferences/
tmp/
When your SDL based iPhone application starts up, it sets the working directory to the main bundle (MySDLApp Home/MySDLApp.app), where your application resources are stored. You cannot write to this directory. Instead, I advise you to write document files to "../Documents/" and preferences to "../Library/Preferences".
More information on this subject is available here:
http://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/Introduction/Introduction.html
Notes -- xcFramework
==============================================================================
The SDL.xcodeproj file now includes a target to build SDL3.xcframework. An xcframework is a new (Xcode 11) uber-framework which can handle any combination of processor type and target OS platform.
In the past, iOS devices were always an ARM variant processor, and the simulator was always i386 or x86_64, and thus libraries could be combined into a single framework for both simulator and device. With the introduction of the Apple Silicon ARM-based machines, regular frameworks would collide as CPU type was no longer sufficient to differentiate the platform. So Apple created the new xcframework library package.
The xcframework target builds into a Products directory alongside the SDL.xcodeproj file, as SDL3.xcframework. This can be brought in to any iOS project and will function properly for both simulator and device, no matter their CPUs. Note that Intel Macs cannot cross-compile for Apple Silicon Macs. If you need AS compatibility, perform this build on an Apple Silicon Mac.
This target requires Xcode 11 or later. The target will simply fail to build if attempted on older Xcodes.
In addition, on Apple platforms, main() cannot be in a dynamically loaded library.
However, unlike in SDL2, in SDL3 SDL_main is implemented inline in SDL_main.h, so you don't need to link against a static libSDL3main.lib, and you don't need to copy a .c file from the SDL3 source either.
This means that iOS apps which used the statically-linked libSDL3.lib and now link with the xcframwork can just `#include <SDL3/SDL_main.h>` in the source file that contains their standard `int main(int argc; char *argv[])` function to get a header-only SDL_main implementation that calls the `SDL_RunApp()` with your standard main function.
Using an xcFramework is similar to using a regular framework. However, issues have been seen with the build system not seeing the headers in the xcFramework. To remedy this, add the path to the xcFramework in your app's target ==> Build Settings ==> Framework Search Paths and mark it recursive (this is critical). Also critical is to remove "*.framework" from Build Settings ==> Sub-Directories to Exclude in Recursive Searches. Clean the build folder, and on your next build the build system should be able to see any of these in your code, as expected:
#include "SDL_main.h"
#include <SDL.h>
#include <SDL_main.h>
Notes -- iPhone SDL limitations
==============================================================================
Windows:
Full-size, single window applications only. You cannot create multi-window SDL applications for iPhone OS. The application window will fill the display, though you have the option of turning on or off the menu-bar (pass SDL_CreateWindow() the flag SDL_WINDOW_BORDERLESS).
Textures:
The optimal texture formats on iOS are SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_XBGR8888, and SDL_PIXELFORMAT_RGB24 pixel formats.
Loading Shared Objects:
This is disabled by default since it seems to break the terms of the iOS SDK agreement for iOS versions prior to iOS 8. It can be re-enabled in SDL_config_ios.h.
Notes -- CoreBluetooth.framework
==============================================================================
SDL_JOYSTICK_HIDAPI is disabled by default. It can give you access to a lot
more game controller devices, but it requires permission from the user before
your app will be able to talk to the Bluetooth hardware. "Made For iOS"
branded controllers do not need this as we don't have to speak to them
directly with raw bluetooth, so many apps can live without this.
You'll need to link with CoreBluetooth.framework and add something like this
to your Info.plist:
<key>NSBluetoothPeripheralUsageDescription</key>
<string>MyApp would like to remain connected to nearby bluetooth Game Controllers and Game Pads even when you're not using the app.</string>
Game Center
==============================================================================
Game Center integration might require that you break up your main loop in order to yield control back to the system. In other words, instead of running an endless main loop, you run each frame in a callback function, using:
int SDL_iPhoneSetAnimationCallback(SDL_Window * window, int interval, void (*callback)(void*), void *callbackParam);
This will set up the given function to be called back on the animation callback, and then you have to return from main() to let the Cocoa event loop run.
e.g.
extern "C"
void ShowFrame(void*)
{
... do event handling, frame logic and rendering ...
}
int main(int argc, char *argv[])
{
... initialize game ...
#ifdef __IOS__
// Initialize the Game Center for scoring and matchmaking
InitGameCenter();
// Set up the game to run in the window animation callback on iOS
// so that Game Center and so forth works correctly.
SDL_iPhoneSetAnimationCallback(window, 1, ShowFrame, NULL);
#else
while ( running ) {
ShowFrame(0);
DelayFrame();
}
#endif
return 0;
}
Deploying to older versions of iOS
==============================================================================
SDL supports deploying to older versions of iOS than are supported by the latest version of Xcode, all the way back to iOS 8.0
In order to do that you need to download an older version of Xcode:
https://developer.apple.com/download/more/?name=Xcode
Open the package contents of the older Xcode and your newer version of Xcode and copy over the folders in Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport
Then open the file Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/SDKSettings.plist and add the versions of iOS you want to deploy to the key Root/DefaultProperties/DEPLOYMENT_TARGET_SUGGESTED_VALUES
Open your project and set your deployment target to the desired version of iOS
Finally, remove GameController from the list of frameworks linked by your application and edit the build settings for "Other Linker Flags" and add -weak_framework GameController

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KMSDRM on *BSD
==================================================
KMSDRM is supported on FreeBSD and OpenBSD. DragonFlyBSD works but requires being a root user. NetBSD isn't supported yet because the application will crash when creating the KMSDRM screen.
WSCONS support has been brought back, but only as an input backend. It will not be brought back as a video backend to ease maintenance.
OpenBSD note: Note that the video backend assumes that the user has read/write permissions to the /dev/drm* devices.
SDL WSCONS input backend features
===================================================
1. It is keymap-aware; it will work properly with different keymaps.
2. It has mouse support.
3. Accent input is supported.
4. Compose keys are supported.
5. AltGr and Meta Shift keys work as intended.
Partially working or no input on OpenBSD/NetBSD.
==================================================
The WSCONS input backend needs read/write access to the /dev/wskbd* devices, without which it will not work properly. /dev/wsmouse must also be read/write accessible, otherwise mouse input will not work.
Partially working or no input on FreeBSD.
==================================================
The evdev devices are only accessible to the root user by default. Edit devfs rules to allow access to such devices. The /dev/kbd* devices are also only accessible to the root user by default. Edit devfs rules to allow access to such devices.
KMSDRM on *BSD
==================================================
KMSDRM is supported on FreeBSD and OpenBSD. DragonFlyBSD works but requires being a root user. NetBSD isn't supported yet because the application will crash when creating the KMSDRM screen.
WSCONS support has been brought back, but only as an input backend. It will not be brought back as a video backend to ease maintenance.
OpenBSD note: Note that the video backend assumes that the user has read/write permissions to the /dev/drm* devices.
SDL WSCONS input backend features
===================================================
1. It is keymap-aware; it will work properly with different keymaps.
2. It has mouse support.
3. Accent input is supported.
4. Compose keys are supported.
5. AltGr and Meta Shift keys work as intended.
Partially working or no input on OpenBSD/NetBSD.
==================================================
The WSCONS input backend needs read/write access to the /dev/wskbd* devices, without which it will not work properly. /dev/wsmouse must also be read/write accessible, otherwise mouse input will not work.
Partially working or no input on FreeBSD.
==================================================
The evdev devices are only accessible to the root user by default. Edit devfs rules to allow access to such devices. The /dev/kbd* devices are also only accessible to the root user by default. Edit devfs rules to allow access to such devices.

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Linux
================================================================================
By default SDL will only link against glibc, the rest of the features will be
enabled dynamically at runtime depending on the available features on the target
system. So, for example if you built SDL with XRandR support and the target
system does not have the XRandR libraries installed, it will be disabled
at runtime, and you won't get a missing library error, at least with the
default configuration parameters.
Build Dependencies
--------------------------------------------------------------------------------
Ubuntu 18.04, all available features enabled:
sudo apt-get install build-essential git make \
pkg-config cmake ninja-build gnome-desktop-testing libasound2-dev libpulse-dev \
libaudio-dev libjack-dev libsndio-dev libx11-dev libxext-dev \
libxrandr-dev libxcursor-dev libxfixes-dev libxi-dev libxss-dev \
libxkbcommon-dev libdrm-dev libgbm-dev libgl1-mesa-dev libgles2-mesa-dev \
libegl1-mesa-dev libdbus-1-dev libibus-1.0-dev libudev-dev fcitx-libs-dev
Ubuntu 22.04+ can also add `libpipewire-0.3-dev libwayland-dev libdecor-0-dev` to that command line.
Fedora 35, all available features enabled:
sudo yum install gcc git-core make cmake \
alsa-lib-devel pulseaudio-libs-devel nas-devel pipewire-devel \
libX11-devel libXext-devel libXrandr-devel libXcursor-devel libXfixes-devel \
libXi-devel libXScrnSaver-devel dbus-devel ibus-devel fcitx-devel \
systemd-devel mesa-libGL-devel libxkbcommon-devel mesa-libGLES-devel \
mesa-libEGL-devel vulkan-devel wayland-devel wayland-protocols-devel \
libdrm-devel mesa-libgbm-devel libusb-devel libdecor-devel \
pipewire-jack-audio-connection-kit-devel \
NOTES:
- The sndio audio target is unavailable on Fedora (but probably not what you
should want to use anyhow).
Joystick does not work
--------------------------------------------------------------------------------
If you compiled or are using a version of SDL with udev support (and you should!)
there's a few issues that may cause SDL to fail to detect your joystick. To
debug this, start by installing the evtest utility. On Ubuntu/Debian:
sudo apt-get install evtest
Then run:
sudo evtest
You'll hopefully see your joystick listed along with a name like "/dev/input/eventXX"
Now run:
cat /dev/input/event/XX
If you get a permission error, you need to set a udev rule to change the mode of
your device (see below)
Also, try:
sudo udevadm info --query=all --name=input/eventXX
If you see a line stating ID_INPUT_JOYSTICK=1, great, if you don't see it,
you need to set up an udev rule to force this variable.
A combined rule for the Saitek Pro Flight Rudder Pedals to fix both issues looks
like:
SUBSYSTEM=="input", ATTRS{idProduct}=="0763", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
SUBSYSTEM=="input", ATTRS{idProduct}=="0764", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
You can set up similar rules for your device by changing the values listed in
idProduct and idVendor. To obtain these values, try:
sudo udevadm info -a --name=input/eventXX | grep idVendor
sudo udevadm info -a --name=input/eventXX | grep idProduct
If multiple values come up for each of these, the one you want is the first one of each.
On other systems which ship with an older udev (such as CentOS), you may need
to set up a rule such as:
SUBSYSTEM=="input", ENV{ID_CLASS}=="joystick", ENV{ID_INPUT_JOYSTICK}="1"
Linux
================================================================================
By default SDL will only link against glibc, the rest of the features will be
enabled dynamically at runtime depending on the available features on the target
system. So, for example if you built SDL with XRandR support and the target
system does not have the XRandR libraries installed, it will be disabled
at runtime, and you won't get a missing library error, at least with the
default configuration parameters.
Build Dependencies
--------------------------------------------------------------------------------
Ubuntu 18.04, all available features enabled:
sudo apt-get install build-essential git make \
pkg-config cmake ninja-build gnome-desktop-testing libasound2-dev libpulse-dev \
libaudio-dev libjack-dev libsndio-dev libx11-dev libxext-dev \
libxrandr-dev libxcursor-dev libxfixes-dev libxi-dev libxss-dev \
libxkbcommon-dev libdrm-dev libgbm-dev libgl1-mesa-dev libgles2-mesa-dev \
libegl1-mesa-dev libdbus-1-dev libibus-1.0-dev libudev-dev fcitx-libs-dev
Ubuntu 22.04+ can also add `libpipewire-0.3-dev libwayland-dev libdecor-0-dev` to that command line.
Fedora 35, all available features enabled:
sudo yum install gcc git-core make cmake \
alsa-lib-devel pulseaudio-libs-devel nas-devel pipewire-devel \
libX11-devel libXext-devel libXrandr-devel libXcursor-devel libXfixes-devel \
libXi-devel libXScrnSaver-devel dbus-devel ibus-devel fcitx-devel \
systemd-devel mesa-libGL-devel libxkbcommon-devel mesa-libGLES-devel \
mesa-libEGL-devel vulkan-devel wayland-devel wayland-protocols-devel \
libdrm-devel mesa-libgbm-devel libusb-devel libdecor-devel \
pipewire-jack-audio-connection-kit-devel \
NOTES:
- The sndio audio target is unavailable on Fedora (but probably not what you
should want to use anyhow).
Joystick does not work
--------------------------------------------------------------------------------
If you compiled or are using a version of SDL with udev support (and you should!)
there's a few issues that may cause SDL to fail to detect your joystick. To
debug this, start by installing the evtest utility. On Ubuntu/Debian:
sudo apt-get install evtest
Then run:
sudo evtest
You'll hopefully see your joystick listed along with a name like "/dev/input/eventXX"
Now run:
cat /dev/input/event/XX
If you get a permission error, you need to set a udev rule to change the mode of
your device (see below)
Also, try:
sudo udevadm info --query=all --name=input/eventXX
If you see a line stating ID_INPUT_JOYSTICK=1, great, if you don't see it,
you need to set up an udev rule to force this variable.
A combined rule for the Saitek Pro Flight Rudder Pedals to fix both issues looks
like:
SUBSYSTEM=="input", ATTRS{idProduct}=="0763", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
SUBSYSTEM=="input", ATTRS{idProduct}=="0764", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
You can set up similar rules for your device by changing the values listed in
idProduct and idVendor. To obtain these values, try:
sudo udevadm info -a --name=input/eventXX | grep idVendor
sudo udevadm info -a --name=input/eventXX | grep idProduct
If multiple values come up for each of these, the one you want is the first one of each.
On other systems which ship with an older udev (such as CentOS), you may need
to set up a rule such as:
SUBSYSTEM=="input", ENV{ID_CLASS}=="joystick", ENV{ID_INPUT_JOYSTICK}="1"

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# macOS
These instructions are for people using Apple's macOS.
From the developer's point of view, macOS is a sort of hybrid Mac and
Unix system, and you have the option of using either traditional
command line tools or Apple's IDE Xcode.
# Command Line Build
To build SDL using the command line, use the CMake build script:
```bash
mkdir build
cd build
cmake ..
cmake --build .
sudo cmake --install .
```
You can also build SDL as a Universal library (a single binary for both
64-bit Intel and ARM architectures):
```bash
mkdir build
cd build
cmake .. "-DCMAKE_OSX_ARCHITECTURES=arm64;x86_64"
cmake --build .
sudo cmake --install .
```
Please note that building SDL requires at least Xcode 6 and the 10.9 SDK.
PowerPC support for macOS has been officially dropped as of SDL 2.0.2.
32-bit Intel and macOS 10.8 runtime support has been officially dropped as
of SDL 2.24.0.
To use the library once it's built, you essential have two possibilities:
use the traditional autoconf/automake/make method, or use Xcode.
# Caveats for using SDL with macOS
If you register your own NSApplicationDelegate (using [NSApp setDelegate:]),
SDL will not register its own. This means that SDL will not terminate using
SDL_Quit if it receives a termination request, it will terminate like a
normal app, and it will not send a SDL_EVENT_DROP_FILE when you request to open a
file with the app. To solve these issues, put the following code in your
NSApplicationDelegate implementation:
```objc
- (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender
{
if (SDL_GetEventState(SDL_EVENT_QUIT) == SDL_ENABLE) {
SDL_Event event;
event.type = SDL_EVENT_QUIT;
SDL_PushEvent(&event);
}
return NSTerminateCancel;
}
- (BOOL)application:(NSApplication *)theApplication openFile:(NSString *)filename
{
if (SDL_GetEventState(SDL_EVENT_DROP_FILE) == SDL_ENABLE) {
SDL_Event event;
event.type = SDL_EVENT_DROP_FILE;
event.drop.file = SDL_strdup([filename UTF8String]);
return (SDL_PushEvent(&event) > 0);
}
return NO;
}
```
# Using the Simple DirectMedia Layer with a traditional Makefile
An existing build system for your SDL app has good chances to work almost
unchanged on macOS, as long as you link with the SDL framework. However,
to produce a "real" Mac binary that you can distribute to users, you need
to put the generated binary into a so called "bundle", which is basically
a fancy folder with a name like "MyCoolGame.app".
To get this build automatically, add something like the following rule to
your Makefile.am:
```make
bundle_contents = APP_NAME.app/Contents
APP_NAME_bundle: EXE_NAME
mkdir -p $(bundle_contents)/MacOS
mkdir -p $(bundle_contents)/Resources
echo "APPL????" > $(bundle_contents)/PkgInfo
$(INSTALL_PROGRAM) $< $(bundle_contents)/MacOS/
```
You should replace `EXE_NAME` with the name of the executable. `APP_NAME` is
what will be visible to the user in the Finder. Usually it will be the same
as `EXE_NAME` but capitalized. E.g. if `EXE_NAME` is "testgame" then `APP_NAME`
usually is "TestGame". You might also want to use `@PACKAGE@` to use the
package name as specified in your configure.ac file.
If your project builds more than one application, you will have to do a bit
more. For each of your target applications, you need a separate rule.
If you want the created bundles to be installed, you may want to add this
rule to your Makefile.am:
```make
install-exec-hook: APP_NAME_bundle
rm -rf $(DESTDIR)$(prefix)/Applications/APP_NAME.app
mkdir -p $(DESTDIR)$(prefix)/Applications/
cp -r $< /$(DESTDIR)$(prefix)Applications/
```
This rule takes the Bundle created by the rule from step 3 and installs them
into "$(DESTDIR)$(prefix)/Applications/".
Again, if you want to install multiple applications, you will have to augment
the make rule accordingly.
But beware! That is only part of the story! With the above, you end up with
a barebones .app bundle, which is double-clickable from the Finder. But
there are some more things you should do before shipping your product...
1. You'll need to copy the SDL framework into the Contents/Frameworks
folder in your bundle, so it is included along with your application.
2. Add an 'Info.plist' to your application. That is a special XML file which
contains some meta-information about your application (like some copyright
information, the version of your app, the name of an optional icon file,
and other things). Part of that information is displayed by the Finder
when you click on the .app, or if you look at the "Get Info" window.
More information about Info.plist files can be found on Apple's homepage.
As a final remark, let me add that I use some of the techniques (and some
variations of them) in [Exult](https://github.com/exult/exult) and
[ScummVM](https://github.com/scummvm/scummvm); both are available in source on
the net, so feel free to take a peek at them for inspiration!
# Using the Simple DirectMedia Layer with Xcode
These instructions are for using Apple's Xcode IDE to build SDL applications.
## First steps
The first thing to do is to unpack the Xcode.tar.gz archive in the
top level SDL directory (where the Xcode.tar.gz archive resides).
Because Stuffit Expander will unpack the archive into a subdirectory,
you should unpack the archive manually from the command line:
```bash
cd [path_to_SDL_source]
tar zxf Xcode.tar.gz
```
This will create a new folder called Xcode, which you can browse
normally from the Finder.
## Building the Framework
The SDL Library is packaged as a framework bundle, an organized
relocatable folder hierarchy of executable code, interface headers,
and additional resources. For practical purposes, you can think of a
framework as a more user and system-friendly shared library, whose library
file behaves more or less like a standard UNIX shared library.
To build the framework, simply open the framework project and build it.
By default, the framework bundle "SDL.framework" is installed in
/Library/Frameworks. Therefore, the testers and project stationary expect
it to be located there. However, it will function the same in any of the
following locations:
* ~/Library/Frameworks
* /Local/Library/Frameworks
* /System/Library/Frameworks
## Build Options
There are two "Build Styles" (See the "Targets" tab) for SDL.
"Deployment" should be used if you aren't tweaking the SDL library.
"Development" should be used to debug SDL apps or the library itself.
## Building the Testers
Open the SDLTest project and build away!
## Using the Project Stationary
Copy the stationary to the indicated folders to access it from
the "New Project" and "Add target" menus. What could be easier?
## Setting up a new project by hand
Some of you won't want to use the Stationary so I'll give some tips:
(this is accurate as of Xcode 12.5.)
* Click "File" -> "New" -> "Project...
* Choose "macOS" and then "App" from the "Application" section.
* Fill out the options in the next window. User interface is "XIB" and
Language is "Objective-C".
* Remove "main.m" from your project
* Remove "MainMenu.xib" from your project
* Remove "AppDelegates.*" from your project
* Add "\$(HOME)/Library/Frameworks/SDL.framework/Headers" to include path
* Add "\$(HOME)/Library/Frameworks" to the frameworks search path
* Add "-framework SDL -framework Foundation -framework AppKit" to "OTHER_LDFLAGS"
* Add your files
* Clean and build
## Building from command line
Use `xcode-build` in the same directory as your .pbxproj file
## Running your app
You can send command line args to your app by either invoking it from
the command line (in *.app/Contents/MacOS) or by entering them in the
Executables" panel of the target settings.
# Implementation Notes
Some things that may be of interest about how it all works...
## Working directory
In SDL 1.2, the working directory of your SDL app is by default set to its
parent, but this is no longer the case in SDL 2.0. SDL2 does change the
working directory, which means it'll be whatever the command line prompt
that launched the program was using, or if launched by double-clicking in
the finger, it will be "/", the _root of the filesystem_. Plan accordingly!
You can use SDL_GetBasePath() to find where the program is running from and
chdir() there directly.
## You have a Cocoa App!
Your SDL app is essentially a Cocoa application. When your app
starts up and the libraries finish loading, a Cocoa procedure is called,
which sets up the working directory and calls your main() method.
You are free to modify your Cocoa app with generally no consequence
to SDL. You cannot, however, easily change the SDL window itself.
Functionality may be added in the future to help this.
# Bug reports
Bugs are tracked at [the GitHub issue tracker](https://github.com/libsdl-org/SDL/issues/).
Please feel free to report bugs there!
# macOS
These instructions are for people using Apple's macOS.
From the developer's point of view, macOS is a sort of hybrid Mac and
Unix system, and you have the option of using either traditional
command line tools or Apple's IDE Xcode.
# Command Line Build
To build SDL using the command line, use the CMake build script:
```bash
mkdir build
cd build
cmake ..
cmake --build .
sudo cmake --install .
```
You can also build SDL as a Universal library (a single binary for both
64-bit Intel and ARM architectures):
```bash
mkdir build
cd build
cmake .. "-DCMAKE_OSX_ARCHITECTURES=arm64;x86_64"
cmake --build .
sudo cmake --install .
```
Please note that building SDL requires at least Xcode 6 and the 10.9 SDK.
PowerPC support for macOS has been officially dropped as of SDL 2.0.2.
32-bit Intel and macOS 10.8 runtime support has been officially dropped as
of SDL 2.24.0.
To use the library once it's built, you essential have two possibilities:
use the traditional autoconf/automake/make method, or use Xcode.
# Caveats for using SDL with macOS
If you register your own NSApplicationDelegate (using [NSApp setDelegate:]),
SDL will not register its own. This means that SDL will not terminate using
SDL_Quit if it receives a termination request, it will terminate like a
normal app, and it will not send a SDL_EVENT_DROP_FILE when you request to open a
file with the app. To solve these issues, put the following code in your
NSApplicationDelegate implementation:
```objc
- (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender
{
if (SDL_GetEventState(SDL_EVENT_QUIT) == SDL_ENABLE) {
SDL_Event event;
event.type = SDL_EVENT_QUIT;
SDL_PushEvent(&event);
}
return NSTerminateCancel;
}
- (BOOL)application:(NSApplication *)theApplication openFile:(NSString *)filename
{
if (SDL_GetEventState(SDL_EVENT_DROP_FILE) == SDL_ENABLE) {
SDL_Event event;
event.type = SDL_EVENT_DROP_FILE;
event.drop.file = SDL_strdup([filename UTF8String]);
return (SDL_PushEvent(&event) > 0);
}
return NO;
}
```
# Using the Simple DirectMedia Layer with a traditional Makefile
An existing build system for your SDL app has good chances to work almost
unchanged on macOS, as long as you link with the SDL framework. However,
to produce a "real" Mac binary that you can distribute to users, you need
to put the generated binary into a so called "bundle", which is basically
a fancy folder with a name like "MyCoolGame.app".
To get this build automatically, add something like the following rule to
your Makefile.am:
```make
bundle_contents = APP_NAME.app/Contents
APP_NAME_bundle: EXE_NAME
mkdir -p $(bundle_contents)/MacOS
mkdir -p $(bundle_contents)/Resources
echo "APPL????" > $(bundle_contents)/PkgInfo
$(INSTALL_PROGRAM) $< $(bundle_contents)/MacOS/
```
You should replace `EXE_NAME` with the name of the executable. `APP_NAME` is
what will be visible to the user in the Finder. Usually it will be the same
as `EXE_NAME` but capitalized. E.g. if `EXE_NAME` is "testgame" then `APP_NAME`
usually is "TestGame". You might also want to use `@PACKAGE@` to use the
package name as specified in your configure.ac file.
If your project builds more than one application, you will have to do a bit
more. For each of your target applications, you need a separate rule.
If you want the created bundles to be installed, you may want to add this
rule to your Makefile.am:
```make
install-exec-hook: APP_NAME_bundle
rm -rf $(DESTDIR)$(prefix)/Applications/APP_NAME.app
mkdir -p $(DESTDIR)$(prefix)/Applications/
cp -r $< /$(DESTDIR)$(prefix)Applications/
```
This rule takes the Bundle created by the rule from step 3 and installs them
into "$(DESTDIR)$(prefix)/Applications/".
Again, if you want to install multiple applications, you will have to augment
the make rule accordingly.
But beware! That is only part of the story! With the above, you end up with
a barebones .app bundle, which is double-clickable from the Finder. But
there are some more things you should do before shipping your product...
1. You'll need to copy the SDL framework into the Contents/Frameworks
folder in your bundle, so it is included along with your application.
2. Add an 'Info.plist' to your application. That is a special XML file which
contains some meta-information about your application (like some copyright
information, the version of your app, the name of an optional icon file,
and other things). Part of that information is displayed by the Finder
when you click on the .app, or if you look at the "Get Info" window.
More information about Info.plist files can be found on Apple's homepage.
As a final remark, let me add that I use some of the techniques (and some
variations of them) in [Exult](https://github.com/exult/exult) and
[ScummVM](https://github.com/scummvm/scummvm); both are available in source on
the net, so feel free to take a peek at them for inspiration!
# Using the Simple DirectMedia Layer with Xcode
These instructions are for using Apple's Xcode IDE to build SDL applications.
## First steps
The first thing to do is to unpack the Xcode.tar.gz archive in the
top level SDL directory (where the Xcode.tar.gz archive resides).
Because Stuffit Expander will unpack the archive into a subdirectory,
you should unpack the archive manually from the command line:
```bash
cd [path_to_SDL_source]
tar zxf Xcode.tar.gz
```
This will create a new folder called Xcode, which you can browse
normally from the Finder.
## Building the Framework
The SDL Library is packaged as a framework bundle, an organized
relocatable folder hierarchy of executable code, interface headers,
and additional resources. For practical purposes, you can think of a
framework as a more user and system-friendly shared library, whose library
file behaves more or less like a standard UNIX shared library.
To build the framework, simply open the framework project and build it.
By default, the framework bundle "SDL.framework" is installed in
/Library/Frameworks. Therefore, the testers and project stationary expect
it to be located there. However, it will function the same in any of the
following locations:
* ~/Library/Frameworks
* /Local/Library/Frameworks
* /System/Library/Frameworks
## Build Options
There are two "Build Styles" (See the "Targets" tab) for SDL.
"Deployment" should be used if you aren't tweaking the SDL library.
"Development" should be used to debug SDL apps or the library itself.
## Building the Testers
Open the SDLTest project and build away!
## Using the Project Stationary
Copy the stationary to the indicated folders to access it from
the "New Project" and "Add target" menus. What could be easier?
## Setting up a new project by hand
Some of you won't want to use the Stationary so I'll give some tips:
(this is accurate as of Xcode 12.5.)
* Click "File" -> "New" -> "Project...
* Choose "macOS" and then "App" from the "Application" section.
* Fill out the options in the next window. User interface is "XIB" and
Language is "Objective-C".
* Remove "main.m" from your project
* Remove "MainMenu.xib" from your project
* Remove "AppDelegates.*" from your project
* Add "\$(HOME)/Library/Frameworks/SDL.framework/Headers" to include path
* Add "\$(HOME)/Library/Frameworks" to the frameworks search path
* Add "-framework SDL -framework Foundation -framework AppKit" to "OTHER_LDFLAGS"
* Add your files
* Clean and build
## Building from command line
Use `xcode-build` in the same directory as your .pbxproj file
## Running your app
You can send command line args to your app by either invoking it from
the command line (in *.app/Contents/MacOS) or by entering them in the
Executables" panel of the target settings.
# Implementation Notes
Some things that may be of interest about how it all works...
## Working directory
In SDL 1.2, the working directory of your SDL app is by default set to its
parent, but this is no longer the case in SDL 2.0. SDL2 does change the
working directory, which means it'll be whatever the command line prompt
that launched the program was using, or if launched by double-clicking in
the finger, it will be "/", the _root of the filesystem_. Plan accordingly!
You can use SDL_GetBasePath() to find where the program is running from and
chdir() there directly.
## You have a Cocoa App!
Your SDL app is essentially a Cocoa application. When your app
starts up and the libraries finish loading, a Cocoa procedure is called,
which sets up the working directory and calls your main() method.
You are free to modify your Cocoa app with generally no consequence
to SDL. You cannot, however, easily change the SDL window itself.
Functionality may be added in the future to help this.
# Bug reports
Bugs are tracked at [the GitHub issue tracker](https://github.com/libsdl-org/SDL/issues/).
Please feel free to report bugs there!

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@ -1,194 +1,194 @@
# Where an SDL program starts running.
## History
SDL has a long, complicated history with starting a program.
In most of the civilized world, an application starts in a C-callable
function named "main". You probably learned it a long time ago:
```c
int main(int argc, char **argv)
{
printf("Hello world!\n");
return 0;
}
```
But not all platforms work like this. Windows apps might want a different
function named "WinMain", for example, so SDL set out to paper over this
difference.
Generally how this would work is: your app would always use the "standard"
`main(argc, argv)` function as its entry point, and `#include` the proper
SDL header before that, which did some macro magic. On platforms that used
a standard `main`, it would do nothing and what you saw was what you got.
But those other platforms! If they needed something that _wasn't_ `main`,
SDL's macro magic would quietly rename your function to `SDL_main`, and
provide its own entry point that called it. Your app was none the wiser and
your code worked everywhere without changes.
## The main entry point in SDL3
Previous versions of SDL had a static library, SDLmain, that you would link
your app against. SDL3 still has the same macro tricks, but the static library
is gone. Now it's supplied by a "single-header library," which means you
`#include <SDL3/SDL_main.h>` and that header will insert a small amount of
code into the source file that included it, so you no longer have to worry
about linking against an extra library that you might need on some platforms.
You just build your app and it works.
You should _only_ include SDL_main.h from one file (the umbrella header,
SDL.h, does _not_ include it), and know that it will `#define main` to
something else, so if you use this symbol elsewhere as a variable name, etc,
it can cause you unexpected problems.
SDL_main.h will also include platform-specific code (WinMain or whatnot) that
calls your _actual_ main function. This is compiled directly into your
program.
If for some reason you need to include SDL_main.h in a file but also _don't_
want it to generate this platform-specific code, you should define a special
macro before includin the header:
```c
#define SDL_MAIN_NOIMPL
```
If you are moving from SDL2, remove any references to the SDLmain static
library from your build system, and you should be done. Things should work as
they always have.
If you have never controlled your process's entry point (you are using SDL
as a module from a general-purpose scripting language interpreter, or you're
using SDL in a plugin for some otherwise-unrelated app), then there is nothing
required of you here; there is no startup code in SDL's entry point code that
is required, so using SDL_main.h is completely optional. Just start using
the SDL API when you are ready.
## Main callbacks in SDL3
There is a second option in SDL3 for how to structure your program. This is
completely optional and you can ignore it if you're happy using a standard
"main" function.
Some platforms would rather your program operate in chunks. Most of the time,
games tend to look like this at the highest level:
```c
int main(int argc, char **argv)
{
initialize();
while (keep_running()) {
handle_new_events();
do_one_frame_of_stuff();
}
deinitialize();
}
```
There are platforms that would rather be in charge of that `while` loop:
iOS would rather you return from main() immediately and then it will let you
know that it's time to update and draw the next frame of video. Emscripten
(programs that run on a web page) absolutely requires this to function at all.
Video targets like Wayland can notify the app when to draw a new frame, to
save battery life and cooperate with the compositor more closely.
In most cases, you can add special-case code to your program to deal with this
on different platforms, but SDL3 offers a system to handle this transparently on
the app's behalf.
To use this, you have to redesign the highest level of your app a little. Once
you do, it'll work on all supported SDL platforms without problems and
`#ifdef`s in your code.
Instead of providing a "main" function, under this system, you would provide
several functions that SDL will call as appropriate.
Using the callback entry points works on every platform, because on platforms
that don't require them, we can fake them with a simple loop in an internal
implementation of the usual SDL_main.
The primary way we expect people to write SDL apps is still with SDL_main, and
this is not intended to replace it. If the app chooses to use this, it just
removes some platform-specific details they might have to otherwise manage,
and maybe removes a barrier to entry on some future platform. And you might
find you enjoy structuring your program like this more!
## How to use main callbacks in SDL3
To enable the callback entry points, you include SDL_main.h with an extra define,
from a single source file in your project:
```c
#define SDL_MAIN_USE_CALLBACKS
#include <SDL3/SDL_main.h>
```
Once you do this, you do not write a "main" function at all (and if you do,
the app will likely fail to link). Instead, you provide the following
functions:
First:
```c
int SDL_AppInit(int argc, char **argv);
```
This will be called _once_ before anything else. argc/argv work like they
always do. If this returns 0, the app runs. If it returns < 0, the app calls
SDL_AppQuit and terminates with an exit code that reports an error to the
platform. If it returns > 0, the app calls SDL_AppQuit and terminates with
an exit code that reports success to the platform. This function should not
go into an infinite mainloop; it should do any one-time startup it requires
and then return.
Then:
```c
int SDL_AppIterate(void);
```
This is called over and over, possibly at the refresh rate of the display or
some other metric that the platform dictates. This is where the heart of your
app runs. It should return as quickly as reasonably possible, but it's not a
"run one memcpy and that's all the time you have" sort of thing. The app
should do any game updates, and render a frame of video. If it returns < 0,
SDL will call SDL_AppQuit and terminate the process with an exit code that
reports an error to the platform. If it returns > 0, the app calls
SDL_AppQuit and terminates with an exit code that reports success to the
platform. If it returns 0, then SDL_AppIterate will be called again at some
regular frequency. The platform may choose to run this more or less (perhaps
less in the background, etc), or it might just call this function in a loop
as fast as possible. You do not check the event queue in this function
(SDL_AppEvent exists for that).
Next:
```c
int SDL_AppEvent(const SDL_Event *event);
```
This will be called whenever an SDL event arrives, on the thread that runs
SDL_AppIterate. Your app should also not call SDL_PollEvent, SDL_PumpEvent,
etc, as SDL will manage all this for you. Return values are the same as from
SDL_AppIterate(), so you can terminate in response to SDL_EVENT_QUIT, etc.
Finally:
```c
void SDL_AppQuit(void);
```
This is called once before terminating the app--assuming the app isn't being
forcibly killed or crashed--as a last chance to clean up. After this returns,
SDL will call SDL_Quit so the app doesn't have to (but it's safe for the app
to call it, too). Process termination proceeds as if the app returned normally
from main(), so atexit handles will run, if your platform supports that.
# Where an SDL program starts running.
## History
SDL has a long, complicated history with starting a program.
In most of the civilized world, an application starts in a C-callable
function named "main". You probably learned it a long time ago:
```c
int main(int argc, char **argv)
{
printf("Hello world!\n");
return 0;
}
```
But not all platforms work like this. Windows apps might want a different
function named "WinMain", for example, so SDL set out to paper over this
difference.
Generally how this would work is: your app would always use the "standard"
`main(argc, argv)` function as its entry point, and `#include` the proper
SDL header before that, which did some macro magic. On platforms that used
a standard `main`, it would do nothing and what you saw was what you got.
But those other platforms! If they needed something that _wasn't_ `main`,
SDL's macro magic would quietly rename your function to `SDL_main`, and
provide its own entry point that called it. Your app was none the wiser and
your code worked everywhere without changes.
## The main entry point in SDL3
Previous versions of SDL had a static library, SDLmain, that you would link
your app against. SDL3 still has the same macro tricks, but the static library
is gone. Now it's supplied by a "single-header library," which means you
`#include <SDL3/SDL_main.h>` and that header will insert a small amount of
code into the source file that included it, so you no longer have to worry
about linking against an extra library that you might need on some platforms.
You just build your app and it works.
You should _only_ include SDL_main.h from one file (the umbrella header,
SDL.h, does _not_ include it), and know that it will `#define main` to
something else, so if you use this symbol elsewhere as a variable name, etc,
it can cause you unexpected problems.
SDL_main.h will also include platform-specific code (WinMain or whatnot) that
calls your _actual_ main function. This is compiled directly into your
program.
If for some reason you need to include SDL_main.h in a file but also _don't_
want it to generate this platform-specific code, you should define a special
macro before includin the header:
```c
#define SDL_MAIN_NOIMPL
```
If you are moving from SDL2, remove any references to the SDLmain static
library from your build system, and you should be done. Things should work as
they always have.
If you have never controlled your process's entry point (you are using SDL
as a module from a general-purpose scripting language interpreter, or you're
using SDL in a plugin for some otherwise-unrelated app), then there is nothing
required of you here; there is no startup code in SDL's entry point code that
is required, so using SDL_main.h is completely optional. Just start using
the SDL API when you are ready.
## Main callbacks in SDL3
There is a second option in SDL3 for how to structure your program. This is
completely optional and you can ignore it if you're happy using a standard
"main" function.
Some platforms would rather your program operate in chunks. Most of the time,
games tend to look like this at the highest level:
```c
int main(int argc, char **argv)
{
initialize();
while (keep_running()) {
handle_new_events();
do_one_frame_of_stuff();
}
deinitialize();
}
```
There are platforms that would rather be in charge of that `while` loop:
iOS would rather you return from main() immediately and then it will let you
know that it's time to update and draw the next frame of video. Emscripten
(programs that run on a web page) absolutely requires this to function at all.
Video targets like Wayland can notify the app when to draw a new frame, to
save battery life and cooperate with the compositor more closely.
In most cases, you can add special-case code to your program to deal with this
on different platforms, but SDL3 offers a system to handle this transparently on
the app's behalf.
To use this, you have to redesign the highest level of your app a little. Once
you do, it'll work on all supported SDL platforms without problems and
`#ifdef`s in your code.
Instead of providing a "main" function, under this system, you would provide
several functions that SDL will call as appropriate.
Using the callback entry points works on every platform, because on platforms
that don't require them, we can fake them with a simple loop in an internal
implementation of the usual SDL_main.
The primary way we expect people to write SDL apps is still with SDL_main, and
this is not intended to replace it. If the app chooses to use this, it just
removes some platform-specific details they might have to otherwise manage,
and maybe removes a barrier to entry on some future platform. And you might
find you enjoy structuring your program like this more!
## How to use main callbacks in SDL3
To enable the callback entry points, you include SDL_main.h with an extra define,
from a single source file in your project:
```c
#define SDL_MAIN_USE_CALLBACKS
#include <SDL3/SDL_main.h>
```
Once you do this, you do not write a "main" function at all (and if you do,
the app will likely fail to link). Instead, you provide the following
functions:
First:
```c
int SDL_AppInit(int argc, char **argv);
```
This will be called _once_ before anything else. argc/argv work like they
always do. If this returns 0, the app runs. If it returns < 0, the app calls
SDL_AppQuit and terminates with an exit code that reports an error to the
platform. If it returns > 0, the app calls SDL_AppQuit and terminates with
an exit code that reports success to the platform. This function should not
go into an infinite mainloop; it should do any one-time startup it requires
and then return.
Then:
```c
int SDL_AppIterate(void);
```
This is called over and over, possibly at the refresh rate of the display or
some other metric that the platform dictates. This is where the heart of your
app runs. It should return as quickly as reasonably possible, but it's not a
"run one memcpy and that's all the time you have" sort of thing. The app
should do any game updates, and render a frame of video. If it returns < 0,
SDL will call SDL_AppQuit and terminate the process with an exit code that
reports an error to the platform. If it returns > 0, the app calls
SDL_AppQuit and terminates with an exit code that reports success to the
platform. If it returns 0, then SDL_AppIterate will be called again at some
regular frequency. The platform may choose to run this more or less (perhaps
less in the background, etc), or it might just call this function in a loop
as fast as possible. You do not check the event queue in this function
(SDL_AppEvent exists for that).
Next:
```c
int SDL_AppEvent(const SDL_Event *event);
```
This will be called whenever an SDL event arrives, on the thread that runs
SDL_AppIterate. Your app should also not call SDL_PollEvent, SDL_PumpEvent,
etc, as SDL will manage all this for you. Return values are the same as from
SDL_AppIterate(), so you can terminate in response to SDL_EVENT_QUIT, etc.
Finally:
```c
void SDL_AppQuit(void);
```
This is called once before terminating the app--assuming the app isn't being
forcibly killed or crashed--as a last chance to clean up. After this returns,
SDL will call SDL_Quit so the app doesn't have to (but it's safe for the app
to call it, too). Process termination proceeds as if the app returned normally
from main(), so atexit handles will run, if your platform supports that.

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# Nintendo 3DS
SDL port for the Nintendo 3DS [Homebrew toolchain](https://devkitpro.org/) contributed by:
- [Pierre Wendling](https://github.com/FtZPetruska)
Credits to:
- The awesome people who ported SDL to other homebrew platforms.
- The Devkitpro team for making all the tools necessary to achieve this.
## Building
To build for the Nintendo 3DS, make sure you have devkitARM and cmake installed and run:
```bash
cmake -S. -Bbuild -DCMAKE_TOOLCHAIN_FILE="$DEVKITPRO/cmake/3DS.cmake" -DCMAKE_BUILD_TYPE=Release
cmake --build build
cmake --install build
```
## Notes
- Currently only software rendering is supported.
- SDL3_main should be used to ensure ROMFS is enabled - this is done with `#include <SDL3/SDL_main.h>` in the source file that contains your main function.
- By default, the extra L2 cache and higher clock speeds of the New 2/3DS lineup are enabled. If you wish to turn it off, use `osSetSpeedupEnable(false)` in your main function.
- `SDL_GetBasePath` returns the romfs root instead of the executable's directory.
- The Nintendo 3DS uses a cooperative threading model on a single core, meaning a thread will never yield unless done manually through the `SDL_Delay` functions, or blocking waits (`SDL_LockMutex`, `SDL_WaitSemaphore`, `SDL_WaitCondition`, `SDL_WaitThread`). To avoid starving other threads, `SDL_TryWaitSemaphore` and `SDL_WaitSemaphoreTimeout` will yield if they fail to acquire the semaphore, see https://github.com/libsdl-org/SDL/pull/6776 for more information.
# Nintendo 3DS
SDL port for the Nintendo 3DS [Homebrew toolchain](https://devkitpro.org/) contributed by:
- [Pierre Wendling](https://github.com/FtZPetruska)
Credits to:
- The awesome people who ported SDL to other homebrew platforms.
- The Devkitpro team for making all the tools necessary to achieve this.
## Building
To build for the Nintendo 3DS, make sure you have devkitARM and cmake installed and run:
```bash
cmake -S. -Bbuild -DCMAKE_TOOLCHAIN_FILE="$DEVKITPRO/cmake/3DS.cmake" -DCMAKE_BUILD_TYPE=Release
cmake --build build
cmake --install build
```
## Notes
- Currently only software rendering is supported.
- SDL3_main should be used to ensure ROMFS is enabled - this is done with `#include <SDL3/SDL_main.h>` in the source file that contains your main function.
- By default, the extra L2 cache and higher clock speeds of the New 2/3DS lineup are enabled. If you wish to turn it off, use `osSetSpeedupEnable(false)` in your main function.
- `SDL_GetBasePath` returns the romfs root instead of the executable's directory.
- The Nintendo 3DS uses a cooperative threading model on a single core, meaning a thread will never yield unless done manually through the `SDL_Delay` functions, or blocking waits (`SDL_LockMutex`, `SDL_WaitSemaphore`, `SDL_WaitCondition`, `SDL_WaitThread`). To avoid starving other threads, `SDL_TryWaitSemaphore` and `SDL_WaitSemaphoreTimeout` will yield if they fail to acquire the semaphore, see https://github.com/libsdl-org/SDL/pull/6776 for more information.

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Nokia N-Gage
============
SDL port for Symbian S60v1 and v2 with a main focus on the Nokia N-Gage
(Classic and QD) by [Michael Fitzmayer](https://github.com/mupfdev).
Compiling
---------
SDL is part of the [N-Gage SDK.](https://github.com/ngagesdk) project.
The library is included in the
[toolchain](https://github.com/ngagesdk/ngage-toolchain) as a
sub-module.
A complete example project based on SDL can be found in the GitHub
account of the SDK: [Wordle](https://github.com/ngagesdk/wordle).
Current level of implementation
-------------------------------
The video driver currently provides full screen video support with
keyboard input.
At the moment only the software renderer works.
Audio is not yet implemented.
Acknowledgements
----------------
Thanks to Hannu Viitala, Kimmo Kinnunen and Markus Mertama for the
valuable insight into Symbian programming. Without the SDL 1.2 port
which was specially developed for CDoom (Doom for the Nokia 9210), this
adaptation would not have been possible.
I would like to thank my friends
[Razvan](https://twitter.com/bewarerazvan) and [Dan
Whelan](https://danwhelan.ie/), for their continuous support. Without
you and the [N-Gage community](https://discord.gg/dbUzqJ26vs), I would
have lost my patience long ago.
Last but not least, I would like to thank the development team of
[EKA2L1](https://12z1.com/) (an experimental Symbian OS emulator). Your
patience and support in troubleshooting helped me a lot.
Nokia N-Gage
============
SDL port for Symbian S60v1 and v2 with a main focus on the Nokia N-Gage
(Classic and QD) by [Michael Fitzmayer](https://github.com/mupfdev).
Compiling
---------
SDL is part of the [N-Gage SDK.](https://github.com/ngagesdk) project.
The library is included in the
[toolchain](https://github.com/ngagesdk/ngage-toolchain) as a
sub-module.
A complete example project based on SDL can be found in the GitHub
account of the SDK: [Wordle](https://github.com/ngagesdk/wordle).
Current level of implementation
-------------------------------
The video driver currently provides full screen video support with
keyboard input.
At the moment only the software renderer works.
Audio is not yet implemented.
Acknowledgements
----------------
Thanks to Hannu Viitala, Kimmo Kinnunen and Markus Mertama for the
valuable insight into Symbian programming. Without the SDL 1.2 port
which was specially developed for CDoom (Doom for the Nokia 9210), this
adaptation would not have been possible.
I would like to thank my friends
[Razvan](https://twitter.com/bewarerazvan) and [Dan
Whelan](https://danwhelan.ie/), for their continuous support. Without
you and the [N-Gage community](https://discord.gg/dbUzqJ26vs), I would
have lost my patience long ago.
Last but not least, I would like to thank the development team of
[EKA2L1](https://12z1.com/) (an experimental Symbian OS emulator). Your
patience and support in troubleshooting helped me a lot.

16
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@ -1,8 +1,8 @@
Platforms
=========
We maintain the list of supported platforms on our wiki now, and how to
build and install SDL for those platforms:
https://wiki.libsdl.org/Installation
Platforms
=========
We maintain the list of supported platforms on our wiki now, and how to
build and install SDL for those platforms:
https://wiki.libsdl.org/Installation

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Porting
=======
* Porting To A New Platform
The first thing you have to do when porting to a new platform, is look at
include/SDL_platform.h and create an entry there for your operating system.
The standard format is "__PLATFORM__", where PLATFORM is the name of the OS.
Ideally SDL_platform_defines.h will be able to auto-detect the system it's building
on based on C preprocessor symbols.
There are two basic ways of building SDL at the moment:
1. CMake: cmake -S . -B build && cmake --build build && cmake --install install
If you have a system that supports CMake, then you might try this. Edit CMakeLists.txt,
take a look at the large section labelled:
"Platform-specific options and settings!"
Add a section for your platform, and then re-run 'cmake -S . -B build' and build!
2. Using an IDE:
If you're using an IDE or other non-configure build system, you'll probably want to create a custom `SDL_build_config.h` for your platform. Edit `include/build_config/SDL_build_config.h`, add a section for your platform, and create a custom `SDL_build_config_{platform}.h`, based on `SDL_build_config_minimal.h` and `SDL_build_config.h.cmake`
Add the top level include directory to the header search path, and then add
the following sources to the project:
src/*.c
src/atomic/*.c
src/audio/*.c
src/cpuinfo/*.c
src/events/*.c
src/file/*.c
src/haptic/*.c
src/joystick/*.c
src/power/*.c
src/render/*.c
src/render/software/*.c
src/stdlib/*.c
src/thread/*.c
src/timer/*.c
src/video/*.c
src/audio/disk/*.c
src/audio/dummy/*.c
src/filesystem/dummy/*.c
src/video/dummy/*.c
src/haptic/dummy/*.c
src/joystick/dummy/*.c
src/thread/generic/*.c
src/timer/dummy/*.c
src/loadso/dummy/*.c
Once you have a working library without any drivers, you can go back to each
of the major subsystems and start implementing drivers for your platform.
If you have any questions, don't hesitate to ask on the SDL mailing list:
http://www.libsdl.org/mailing-list.php
Enjoy!
Sam Lantinga (slouken@libsdl.org)
Porting
=======
* Porting To A New Platform
The first thing you have to do when porting to a new platform, is look at
include/SDL_platform.h and create an entry there for your operating system.
The standard format is "__PLATFORM__", where PLATFORM is the name of the OS.
Ideally SDL_platform_defines.h will be able to auto-detect the system it's building
on based on C preprocessor symbols.
There are two basic ways of building SDL at the moment:
1. CMake: cmake -S . -B build && cmake --build build && cmake --install install
If you have a system that supports CMake, then you might try this. Edit CMakeLists.txt,
take a look at the large section labelled:
"Platform-specific options and settings!"
Add a section for your platform, and then re-run 'cmake -S . -B build' and build!
2. Using an IDE:
If you're using an IDE or other non-configure build system, you'll probably want to create a custom `SDL_build_config.h` for your platform. Edit `include/build_config/SDL_build_config.h`, add a section for your platform, and create a custom `SDL_build_config_{platform}.h`, based on `SDL_build_config_minimal.h` and `SDL_build_config.h.cmake`
Add the top level include directory to the header search path, and then add
the following sources to the project:
src/*.c
src/atomic/*.c
src/audio/*.c
src/cpuinfo/*.c
src/events/*.c
src/file/*.c
src/haptic/*.c
src/joystick/*.c
src/power/*.c
src/render/*.c
src/render/software/*.c
src/stdlib/*.c
src/thread/*.c
src/timer/*.c
src/video/*.c
src/audio/disk/*.c
src/audio/dummy/*.c
src/filesystem/dummy/*.c
src/video/dummy/*.c
src/haptic/dummy/*.c
src/joystick/dummy/*.c
src/thread/generic/*.c
src/timer/dummy/*.c
src/loadso/dummy/*.c
Once you have a working library without any drivers, you can go back to each
of the major subsystems and start implementing drivers for your platform.
If you have any questions, don't hesitate to ask on the SDL mailing list:
http://www.libsdl.org/mailing-list.php
Enjoy!
Sam Lantinga (slouken@libsdl.org)

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PS2
======
SDL port for the Sony Playstation 2 contributed by:
- Francisco Javier Trujillo Mata
Credit to
- The guys that ported SDL to PSP & Vita because I'm taking them as reference.
- David G. F. for helping me with several issues and tests.
## Building
To build SDL library for the PS2, make sure you have the latest PS2Dev status and run:
```bash
cmake -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=$PS2DEV/ps2sdk/ps2dev.cmake
cmake --build build
cmake --install build
```
## Hints
The PS2 port has a special Hint for having a dynamic VSYNC. The Hint is `SDL_HINT_PS2_DYNAMIC_VSYNC`.
If you enabled the dynamic vsync having as well `SDL_RENDERER_PRESENTVSYNC` enabled, then if the app is not able to run at 60 FPS, automatically the `vsync` will be disabled having a better performance, instead of dropping FPS to 30.
## Notes
If you trying to debug a SDL app through [ps2client](https://github.com/ps2dev/ps2client) you need to avoid the IOP reset, otherwise you will lose the connection with your computer.
So to avoid the reset of the IOP CPU, you need to call to the macro `SDL_PS2_SKIP_IOP_RESET();`.
It could be something similar as:
```c
.....
SDL_PS2_SKIP_IOP_RESET();
int main(int argc, char *argv[])
{
.....
```
For a release binary is recommendable to reset the IOP always.
Remember to do a clean compilation everytime you enable or disable the `SDL_PS2_SKIP_IOP_RESET` otherwise the change won't be reflected.
## Getting PS2 Dev
[Installing PS2 Dev](https://github.com/ps2dev/ps2dev)
## Running on PCSX2 Emulator
[PCSX2](https://github.com/PCSX2/pcsx2)
[More PCSX2 information](https://pcsx2.net/)
## To Do
- PS2 Screen Keyboard
- Dialogs
- Others
PS2
======
SDL port for the Sony Playstation 2 contributed by:
- Francisco Javier Trujillo Mata
Credit to
- The guys that ported SDL to PSP & Vita because I'm taking them as reference.
- David G. F. for helping me with several issues and tests.
## Building
To build SDL library for the PS2, make sure you have the latest PS2Dev status and run:
```bash
cmake -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=$PS2DEV/ps2sdk/ps2dev.cmake
cmake --build build
cmake --install build
```
## Hints
The PS2 port has a special Hint for having a dynamic VSYNC. The Hint is `SDL_HINT_PS2_DYNAMIC_VSYNC`.
If you enabled the dynamic vsync having as well `SDL_RENDERER_PRESENTVSYNC` enabled, then if the app is not able to run at 60 FPS, automatically the `vsync` will be disabled having a better performance, instead of dropping FPS to 30.
## Notes
If you trying to debug a SDL app through [ps2client](https://github.com/ps2dev/ps2client) you need to avoid the IOP reset, otherwise you will lose the connection with your computer.
So to avoid the reset of the IOP CPU, you need to call to the macro `SDL_PS2_SKIP_IOP_RESET();`.
It could be something similar as:
```c
.....
SDL_PS2_SKIP_IOP_RESET();
int main(int argc, char *argv[])
{
.....
```
For a release binary is recommendable to reset the IOP always.
Remember to do a clean compilation everytime you enable or disable the `SDL_PS2_SKIP_IOP_RESET` otherwise the change won't be reflected.
## Getting PS2 Dev
[Installing PS2 Dev](https://github.com/ps2dev/ps2dev)
## Running on PCSX2 Emulator
[PCSX2](https://github.com/PCSX2/pcsx2)
[More PCSX2 information](https://pcsx2.net/)
## To Do
- PS2 Screen Keyboard
- Dialogs
- Others

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PSP
======
SDL port for the Sony PSP contributed by:
- Captian Lex
- Francisco Javier Trujillo Mata
- Wouter Wijsman
Credit to
Marcus R.Brown,Jim Paris,Matthew H for the original SDL 1.2 for PSP
Geecko for his PSP GU lib "Glib2d"
## Building
To build SDL library for the PSP, make sure you have the latest PSPDev status and run:
```bash
cmake -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=$PSPDEV/psp/share/pspdev.cmake
cmake --build build
cmake --install build
```
## Getting PSP Dev
[Installing PSP Dev](https://github.com/pspdev/pspdev)
## Running on PPSSPP Emulator
[PPSSPP](https://github.com/hrydgard/ppsspp)
[Build Instructions](https://github.com/hrydgard/ppsspp/wiki/Build-instructions)
## Compiling a HelloWorld
[PSP Hello World](https://psp-dev.org/doku.php?id=tutorial:hello_world)
## To Do
- PSP Screen Keyboard
- Dialogs
PSP
======
SDL port for the Sony PSP contributed by:
- Captian Lex
- Francisco Javier Trujillo Mata
- Wouter Wijsman
Credit to
Marcus R.Brown,Jim Paris,Matthew H for the original SDL 1.2 for PSP
Geecko for his PSP GU lib "Glib2d"
## Building
To build SDL library for the PSP, make sure you have the latest PSPDev status and run:
```bash
cmake -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=$PSPDEV/psp/share/pspdev.cmake
cmake --build build
cmake --install build
```
## Getting PSP Dev
[Installing PSP Dev](https://github.com/pspdev/pspdev)
## Running on PPSSPP Emulator
[PPSSPP](https://github.com/hrydgard/ppsspp)
[Build Instructions](https://github.com/hrydgard/ppsspp/wiki/Build-instructions)
## Compiling a HelloWorld
[PSP Hello World](https://psp-dev.org/doku.php?id=tutorial:hello_world)
## To Do
- PSP Screen Keyboard
- Dialogs

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Raspberry Pi
============
Requirements:
Raspbian (other Linux distros may work as well).
Features
--------
* Works without X11
* Hardware accelerated OpenGL ES 2.x
* Sound via ALSA
* Input (mouse/keyboard/joystick) via EVDEV
* Hotplugging of input devices via UDEV
Raspbian Build Dependencies
---------------------------
sudo apt-get install libudev-dev libasound2-dev libdbus-1-dev
You also need the VideoCore binary stuff that ships in /opt/vc for EGL and
OpenGL ES 2.x, it usually comes pre-installed, but in any case:
sudo apt-get install libraspberrypi0 libraspberrypi-bin libraspberrypi-dev
NEON
----
If your Pi has NEON support, make sure you add -mfpu=neon to your CFLAGS so
that SDL will select some otherwise-disabled highly-optimized code. The
original Pi units don't have NEON, the Pi2 probably does, and the Pi3
definitely does.
Cross compiling from x86 Linux
------------------------------
To cross compile SDL for Raspbian from your desktop machine, you'll need a
Raspbian system root and the cross compilation tools. We'll assume these tools
will be placed in /opt/rpi-tools
sudo git clone --depth 1 https://github.com/raspberrypi/tools /opt/rpi-tools
You'll also need a Raspbian binary image.
Get it from: http://downloads.raspberrypi.org/raspbian_latest
After unzipping, you'll get file with a name like: "<date>-wheezy-raspbian.img"
Let's assume the sysroot will be built in /opt/rpi-sysroot.
export SYSROOT=/opt/rpi-sysroot
sudo kpartx -a -v <path_to_raspbian_image>.img
sudo mount -o loop /dev/mapper/loop0p2 /mnt
sudo cp -r /mnt $SYSROOT
sudo apt-get install qemu binfmt-support qemu-user-static
sudo cp /usr/bin/qemu-arm-static $SYSROOT/usr/bin
sudo mount --bind /dev $SYSROOT/dev
sudo mount --bind /proc $SYSROOT/proc
sudo mount --bind /sys $SYSROOT/sys
Now, before chrooting into the ARM sysroot, you'll need to apply a workaround,
edit $SYSROOT/etc/ld.so.preload and comment out all lines in it.
sudo chroot $SYSROOT
apt-get install libudev-dev libasound2-dev libdbus-1-dev libraspberrypi0 libraspberrypi-bin libraspberrypi-dev libx11-dev libxext-dev libxrandr-dev libxcursor-dev libxi-dev libxss-dev
exit
sudo umount $SYSROOT/dev
sudo umount $SYSROOT/proc
sudo umount $SYSROOT/sys
sudo umount /mnt
There's one more fix required, as the libdl.so symlink uses an absolute path
which doesn't quite work in our setup.
sudo rm -rf $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so
sudo ln -s ../../../lib/arm-linux-gnueabihf/libdl.so.2 $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so
The final step is compiling SDL itself.
export CC="/opt/rpi-tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-gcc --sysroot=$SYSROOT -I$SYSROOT/opt/vc/include -I$SYSROOT/usr/include -I$SYSROOT/opt/vc/include/interface/vcos/pthreads -I$SYSROOT/opt/vc/include/interface/vmcs_host/linux"
cd <SDL SOURCE>
mkdir -p build;cd build
LDFLAGS="-L$SYSROOT/opt/vc/lib" ../configure --with-sysroot=$SYSROOT --host=arm-raspberry-linux-gnueabihf --prefix=$PWD/rpi-sdl3-installed --disable-pulseaudio --disable-esd
make
make install
To be able to deploy this to /usr/local in the Raspbian system you need to fix up a few paths:
perl -w -pi -e "s#$PWD/rpi-sdl3-installed#/usr/local#g;" ./rpi-sdl3-installed/lib/libSDL3.la ./rpi-sdl3-installed/lib/pkgconfig/sdl3.pc
Apps don't work or poor video/audio performance
-----------------------------------------------
If you get sound problems, buffer underruns, etc, run "sudo rpi-update" to
update the RPi's firmware. Note that doing so will fix these problems, but it
will also render the CMA - Dynamic Memory Split functionality useless.
Also, by default the Raspbian distro configures the GPU RAM at 64MB, this is too
low in general, specially if a 1080p TV is hooked up.
See here how to configure this setting: http://elinux.org/RPiconfig
Using a fixed gpu_mem=128 is the best option (specially if you updated the
firmware, using CMA probably won't work, at least it's the current case).
No input
--------
Make sure you belong to the "input" group.
sudo usermod -aG input `whoami`
No HDMI Audio
-------------
If you notice that ALSA works but there's no audio over HDMI, try adding:
hdmi_drive=2
to your config.txt file and reboot.
Reference: http://www.raspberrypi.org/phpBB3/viewtopic.php?t=5062
Text Input API support
----------------------
The Text Input API is supported, with translation of scan codes done via the
kernel symbol tables. For this to work, SDL needs access to a valid console.
If you notice there's no SDL_EVENT_TEXT_INPUT message being emitted, double check that
your app has read access to one of the following:
* /proc/self/fd/0
* /dev/tty
* /dev/tty[0...6]
* /dev/vc/0
* /dev/console
This is usually not a problem if you run from the physical terminal (as opposed
to running from a pseudo terminal, such as via SSH). If running from a PTS, a
quick workaround is to run your app as root or add yourself to the tty group,
then re-login to the system.
sudo usermod -aG tty `whoami`
The keyboard layout used by SDL is the same as the one the kernel uses.
To configure the layout on Raspbian:
sudo dpkg-reconfigure keyboard-configuration
To configure the locale, which controls which keys are interpreted as letters,
this determining the CAPS LOCK behavior:
sudo dpkg-reconfigure locales
OpenGL problems
---------------
If you have desktop OpenGL headers installed at build time in your RPi or cross
compilation environment, support for it will be built in. However, the chipset
does not actually have support for it, which causes issues in certain SDL apps
since the presence of OpenGL support supersedes the ES/ES2 variants.
The workaround is to disable OpenGL at configuration time:
./configure --disable-video-opengl
Or if the application uses the Render functions, you can use the SDL_RENDER_DRIVER
environment variable:
export SDL_RENDER_DRIVER=opengles2
Notes
-----
* When launching apps remotely (via SSH), SDL can prevent local keystrokes from
leaking into the console only if it has root privileges. Launching apps locally
does not suffer from this issue.
Raspberry Pi
============
Requirements:
Raspbian (other Linux distros may work as well).
Features
--------
* Works without X11
* Hardware accelerated OpenGL ES 2.x
* Sound via ALSA
* Input (mouse/keyboard/joystick) via EVDEV
* Hotplugging of input devices via UDEV
Raspbian Build Dependencies
---------------------------
sudo apt-get install libudev-dev libasound2-dev libdbus-1-dev
You also need the VideoCore binary stuff that ships in /opt/vc for EGL and
OpenGL ES 2.x, it usually comes pre-installed, but in any case:
sudo apt-get install libraspberrypi0 libraspberrypi-bin libraspberrypi-dev
NEON
----
If your Pi has NEON support, make sure you add -mfpu=neon to your CFLAGS so
that SDL will select some otherwise-disabled highly-optimized code. The
original Pi units don't have NEON, the Pi2 probably does, and the Pi3
definitely does.
Cross compiling from x86 Linux
------------------------------
To cross compile SDL for Raspbian from your desktop machine, you'll need a
Raspbian system root and the cross compilation tools. We'll assume these tools
will be placed in /opt/rpi-tools
sudo git clone --depth 1 https://github.com/raspberrypi/tools /opt/rpi-tools
You'll also need a Raspbian binary image.
Get it from: http://downloads.raspberrypi.org/raspbian_latest
After unzipping, you'll get file with a name like: "<date>-wheezy-raspbian.img"
Let's assume the sysroot will be built in /opt/rpi-sysroot.
export SYSROOT=/opt/rpi-sysroot
sudo kpartx -a -v <path_to_raspbian_image>.img
sudo mount -o loop /dev/mapper/loop0p2 /mnt
sudo cp -r /mnt $SYSROOT
sudo apt-get install qemu binfmt-support qemu-user-static
sudo cp /usr/bin/qemu-arm-static $SYSROOT/usr/bin
sudo mount --bind /dev $SYSROOT/dev
sudo mount --bind /proc $SYSROOT/proc
sudo mount --bind /sys $SYSROOT/sys
Now, before chrooting into the ARM sysroot, you'll need to apply a workaround,
edit $SYSROOT/etc/ld.so.preload and comment out all lines in it.
sudo chroot $SYSROOT
apt-get install libudev-dev libasound2-dev libdbus-1-dev libraspberrypi0 libraspberrypi-bin libraspberrypi-dev libx11-dev libxext-dev libxrandr-dev libxcursor-dev libxi-dev libxss-dev
exit
sudo umount $SYSROOT/dev
sudo umount $SYSROOT/proc
sudo umount $SYSROOT/sys
sudo umount /mnt
There's one more fix required, as the libdl.so symlink uses an absolute path
which doesn't quite work in our setup.
sudo rm -rf $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so
sudo ln -s ../../../lib/arm-linux-gnueabihf/libdl.so.2 $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so
The final step is compiling SDL itself.
export CC="/opt/rpi-tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-gcc --sysroot=$SYSROOT -I$SYSROOT/opt/vc/include -I$SYSROOT/usr/include -I$SYSROOT/opt/vc/include/interface/vcos/pthreads -I$SYSROOT/opt/vc/include/interface/vmcs_host/linux"
cd <SDL SOURCE>
mkdir -p build;cd build
LDFLAGS="-L$SYSROOT/opt/vc/lib" ../configure --with-sysroot=$SYSROOT --host=arm-raspberry-linux-gnueabihf --prefix=$PWD/rpi-sdl3-installed --disable-pulseaudio --disable-esd
make
make install
To be able to deploy this to /usr/local in the Raspbian system you need to fix up a few paths:
perl -w -pi -e "s#$PWD/rpi-sdl3-installed#/usr/local#g;" ./rpi-sdl3-installed/lib/libSDL3.la ./rpi-sdl3-installed/lib/pkgconfig/sdl3.pc
Apps don't work or poor video/audio performance
-----------------------------------------------
If you get sound problems, buffer underruns, etc, run "sudo rpi-update" to
update the RPi's firmware. Note that doing so will fix these problems, but it
will also render the CMA - Dynamic Memory Split functionality useless.
Also, by default the Raspbian distro configures the GPU RAM at 64MB, this is too
low in general, specially if a 1080p TV is hooked up.
See here how to configure this setting: http://elinux.org/RPiconfig
Using a fixed gpu_mem=128 is the best option (specially if you updated the
firmware, using CMA probably won't work, at least it's the current case).
No input
--------
Make sure you belong to the "input" group.
sudo usermod -aG input `whoami`
No HDMI Audio
-------------
If you notice that ALSA works but there's no audio over HDMI, try adding:
hdmi_drive=2
to your config.txt file and reboot.
Reference: http://www.raspberrypi.org/phpBB3/viewtopic.php?t=5062
Text Input API support
----------------------
The Text Input API is supported, with translation of scan codes done via the
kernel symbol tables. For this to work, SDL needs access to a valid console.
If you notice there's no SDL_EVENT_TEXT_INPUT message being emitted, double check that
your app has read access to one of the following:
* /proc/self/fd/0
* /dev/tty
* /dev/tty[0...6]
* /dev/vc/0
* /dev/console
This is usually not a problem if you run from the physical terminal (as opposed
to running from a pseudo terminal, such as via SSH). If running from a PTS, a
quick workaround is to run your app as root or add yourself to the tty group,
then re-login to the system.
sudo usermod -aG tty `whoami`
The keyboard layout used by SDL is the same as the one the kernel uses.
To configure the layout on Raspbian:
sudo dpkg-reconfigure keyboard-configuration
To configure the locale, which controls which keys are interpreted as letters,
this determining the CAPS LOCK behavior:
sudo dpkg-reconfigure locales
OpenGL problems
---------------
If you have desktop OpenGL headers installed at build time in your RPi or cross
compilation environment, support for it will be built in. However, the chipset
does not actually have support for it, which causes issues in certain SDL apps
since the presence of OpenGL support supersedes the ES/ES2 variants.
The workaround is to disable OpenGL at configuration time:
./configure --disable-video-opengl
Or if the application uses the Render functions, you can use the SDL_RENDER_DRIVER
environment variable:
export SDL_RENDER_DRIVER=opengles2
Notes
-----
* When launching apps remotely (via SSH), SDL can prevent local keystrokes from
leaking into the console only if it has root privileges. Launching apps locally
does not suffer from this issue.

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RISC OS
=======
Requirements:
* RISC OS 3.5 or later.
* [SharedUnixLibrary](http://www.riscos.info/packages/LibraryDetails.html#SharedUnixLibraryarm).
* [DigitalRenderer](http://www.riscos.info/packages/LibraryDetails.html#DRendererarm), for audio support.
* [Iconv](http://www.netsurf-browser.org/projects/iconv/), for `SDL_iconv` and related functions.
Compiling:
----------
Currently, SDL for RISC OS only supports compiling with GCCSDK under Linux.
The following commands can be used to build SDL for RISC OS using CMake:
cmake -Bbuild-riscos -DCMAKE_TOOLCHAIN_FILE=$GCCSDK_INSTALL_ENV/toolchain-riscos.cmake -DRISCOS=ON -DCMAKE_INSTALL_PREFIX=$GCCSDK_INSTALL_ENV -DCMAKE_BUILD_TYPE=Release
cmake --build build-riscos
cmake --install build-riscos
When using GCCSDK 4.7.4 release 6 or earlier versions, the builtin atomic functions are broken, meaning it's currently necessary to compile with `-DSDL_GCC_ATOMICS=OFF` using CMake. Newer versions of GCCSDK don't have this problem.
Current level of implementation
-------------------------------
The video driver currently provides full screen video support with keyboard and mouse input. Windowed mode is not yet supported, but is planned in the future. Only software rendering is supported.
The filesystem APIs return either Unix-style paths or RISC OS-style paths based on the value of the `__riscosify_control` symbol, as is standard for UnixLib functions.
The audio, loadso, thread and timer APIs are currently provided by UnixLib.
The joystick, locale and power APIs are not yet implemented.
RISC OS
=======
Requirements:
* RISC OS 3.5 or later.
* [SharedUnixLibrary](http://www.riscos.info/packages/LibraryDetails.html#SharedUnixLibraryarm).
* [DigitalRenderer](http://www.riscos.info/packages/LibraryDetails.html#DRendererarm), for audio support.
* [Iconv](http://www.netsurf-browser.org/projects/iconv/), for `SDL_iconv` and related functions.
Compiling:
----------
Currently, SDL for RISC OS only supports compiling with GCCSDK under Linux.
The following commands can be used to build SDL for RISC OS using CMake:
cmake -Bbuild-riscos -DCMAKE_TOOLCHAIN_FILE=$GCCSDK_INSTALL_ENV/toolchain-riscos.cmake -DRISCOS=ON -DCMAKE_INSTALL_PREFIX=$GCCSDK_INSTALL_ENV -DCMAKE_BUILD_TYPE=Release
cmake --build build-riscos
cmake --install build-riscos
When using GCCSDK 4.7.4 release 6 or earlier versions, the builtin atomic functions are broken, meaning it's currently necessary to compile with `-DSDL_GCC_ATOMICS=OFF` using CMake. Newer versions of GCCSDK don't have this problem.
Current level of implementation
-------------------------------
The video driver currently provides full screen video support with keyboard and mouse input. Windowed mode is not yet supported, but is planned in the future. Only software rendering is supported.
The filesystem APIs return either Unix-style paths or RISC OS-style paths based on the value of the `__riscosify_control` symbol, as is standard for UnixLib functions.
The audio, loadso, thread and timer APIs are currently provided by UnixLib.
The joystick, locale and power APIs are not yet implemented.

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@ -1,81 +1,81 @@
Touch
===========================================================================
System Specific Notes
===========================================================================
Linux:
The linux touch system is currently based off event streams, and proc/bus/devices. The active user must be given permissions to read /dev/input/TOUCHDEVICE, where TOUCHDEVICE is the event stream for your device. Currently only Wacom tablets are supported. If you have an unsupported tablet contact me at jim.tla+sdl_touch@gmail.com and I will help you get support for it.
Mac:
The Mac and iPhone APIs are pretty. If your touch device supports them then you'll be fine. If it doesn't, then there isn't much we can do.
iPhone:
Works out of box.
Windows:
Unfortunately there is no windows support as of yet. Support for Windows 7 is planned, but we currently have no way to test. If you have a Windows 7 WM_TOUCH supported device, and are willing to help test please contact me at jim.tla+sdl_touch@gmail.com
===========================================================================
Events
===========================================================================
SDL_EVENT_FINGER_DOWN:
Sent when a finger (or stylus) is placed on a touch device.
Fields:
* event.tfinger.touchId - the Id of the touch device.
* event.tfinger.fingerId - the Id of the finger which just went down.
* event.tfinger.x - the x coordinate of the touch (0..1)
* event.tfinger.y - the y coordinate of the touch (0..1)
* event.tfinger.pressure - the pressure of the touch (0..1)
SDL_EVENT_FINGER_MOTION:
Sent when a finger (or stylus) is moved on the touch device.
Fields:
Same as SDL_EVENT_FINGER_DOWN but with additional:
* event.tfinger.dx - change in x coordinate during this motion event.
* event.tfinger.dy - change in y coordinate during this motion event.
SDL_EVENT_FINGER_UP:
Sent when a finger (or stylus) is lifted from the touch device.
Fields:
Same as SDL_EVENT_FINGER_DOWN.
===========================================================================
Functions
===========================================================================
SDL provides the ability to access the underlying SDL_Finger structures.
These structures should _never_ be modified.
The following functions are included from SDL_touch.h
To get a SDL_TouchID call SDL_GetTouchDevice(int index).
This returns a SDL_TouchID.
IMPORTANT: If the touch has been removed, or there is no touch with the given index, SDL_GetTouchDevice() will return 0. Be sure to check for this!
The number of touch devices can be queried with SDL_GetNumTouchDevices().
A SDL_TouchID may be used to get pointers to SDL_Finger.
SDL_GetNumTouchFingers(touchID) may be used to get the number of fingers currently down on the device.
The most common reason to access SDL_Finger is to query the fingers outside the event. In most cases accessing the fingers is using the event. This would be accomplished by code like the following:
float x = event.tfinger.x;
float y = event.tfinger.y;
To get a SDL_Finger, call SDL_GetTouchFinger(SDL_TouchID touchID, int index), where touchID is a SDL_TouchID, and index is the requested finger.
This returns a SDL_Finger *, or NULL if the finger does not exist, or has been removed.
A SDL_Finger is guaranteed to be persistent for the duration of a touch, but it will be de-allocated as soon as the finger is removed. This occurs when the SDL_EVENT_FINGER_UP event is _added_ to the event queue, and thus _before_ the SDL_EVENT_FINGER_UP event is polled.
As a result, be very careful to check for NULL return values.
A SDL_Finger has the following fields:
* x, y:
The current coordinates of the touch.
* pressure:
The pressure of the touch.
Please direct questions/comments to:
jim.tla+sdl_touch@gmail.com
(original author, API was changed since)
Touch
===========================================================================
System Specific Notes
===========================================================================
Linux:
The linux touch system is currently based off event streams, and proc/bus/devices. The active user must be given permissions to read /dev/input/TOUCHDEVICE, where TOUCHDEVICE is the event stream for your device. Currently only Wacom tablets are supported. If you have an unsupported tablet contact me at jim.tla+sdl_touch@gmail.com and I will help you get support for it.
Mac:
The Mac and iPhone APIs are pretty. If your touch device supports them then you'll be fine. If it doesn't, then there isn't much we can do.
iPhone:
Works out of box.
Windows:
Unfortunately there is no windows support as of yet. Support for Windows 7 is planned, but we currently have no way to test. If you have a Windows 7 WM_TOUCH supported device, and are willing to help test please contact me at jim.tla+sdl_touch@gmail.com
===========================================================================
Events
===========================================================================
SDL_EVENT_FINGER_DOWN:
Sent when a finger (or stylus) is placed on a touch device.
Fields:
* event.tfinger.touchId - the Id of the touch device.
* event.tfinger.fingerId - the Id of the finger which just went down.
* event.tfinger.x - the x coordinate of the touch (0..1)
* event.tfinger.y - the y coordinate of the touch (0..1)
* event.tfinger.pressure - the pressure of the touch (0..1)
SDL_EVENT_FINGER_MOTION:
Sent when a finger (or stylus) is moved on the touch device.
Fields:
Same as SDL_EVENT_FINGER_DOWN but with additional:
* event.tfinger.dx - change in x coordinate during this motion event.
* event.tfinger.dy - change in y coordinate during this motion event.
SDL_EVENT_FINGER_UP:
Sent when a finger (or stylus) is lifted from the touch device.
Fields:
Same as SDL_EVENT_FINGER_DOWN.
===========================================================================
Functions
===========================================================================
SDL provides the ability to access the underlying SDL_Finger structures.
These structures should _never_ be modified.
The following functions are included from SDL_touch.h
To get a SDL_TouchID call SDL_GetTouchDevice(int index).
This returns a SDL_TouchID.
IMPORTANT: If the touch has been removed, or there is no touch with the given index, SDL_GetTouchDevice() will return 0. Be sure to check for this!
The number of touch devices can be queried with SDL_GetNumTouchDevices().
A SDL_TouchID may be used to get pointers to SDL_Finger.
SDL_GetNumTouchFingers(touchID) may be used to get the number of fingers currently down on the device.
The most common reason to access SDL_Finger is to query the fingers outside the event. In most cases accessing the fingers is using the event. This would be accomplished by code like the following:
float x = event.tfinger.x;
float y = event.tfinger.y;
To get a SDL_Finger, call SDL_GetTouchFinger(SDL_TouchID touchID, int index), where touchID is a SDL_TouchID, and index is the requested finger.
This returns a SDL_Finger *, or NULL if the finger does not exist, or has been removed.
A SDL_Finger is guaranteed to be persistent for the duration of a touch, but it will be de-allocated as soon as the finger is removed. This occurs when the SDL_EVENT_FINGER_UP event is _added_ to the event queue, and thus _before_ the SDL_EVENT_FINGER_UP event is polled.
As a result, be very careful to check for NULL return values.
A SDL_Finger has the following fields:
* x, y:
The current coordinates of the touch.
* pressure:
The pressure of the touch.
Please direct questions/comments to:
jim.tla+sdl_touch@gmail.com
(original author, API was changed since)

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@ -1,60 +1,60 @@
# Versioning
## Since 2.23.0
SDL follows an "odd/even" versioning policy, similar to GLib, GTK, Flatpak
and older versions of the Linux kernel:
* The major version (first part) increases when backwards compatibility
is broken, which will happen infrequently.
* If the minor version (second part) is divisible by 2
(for example 2.24.x, 2.26.x), this indicates a version of SDL that
is believed to be stable and suitable for production use.
* In stable releases, the patchlevel or micro version (third part)
indicates bugfix releases. Bugfix releases should not add or
remove ABI, so the ".0" release (for example 2.24.0) should be
forwards-compatible with all the bugfix releases from the
same cycle (for example 2.24.1).
* The minor version increases when new API or ABI is added, or when
other significant changes are made. Newer minor versions are
backwards-compatible, but not fully forwards-compatible.
For example, programs built against SDL 2.24.x should work fine
with SDL 2.26.x, but programs built against SDL 2.26.x will not
necessarily work with 2.24.x.
* If the minor version (second part) is not divisible by 2
(for example 2.23.x, 2.25.x), this indicates a development prerelease
of SDL that is not suitable for stable software distributions.
Use with caution.
* The patchlevel or micro version (third part) increases with
each prerelease.
* Each prerelease might add new API and/or ABI.
* Prereleases are backwards-compatible with older stable branches.
For example, 2.25.x will be backwards-compatible with 2.24.x.
* Prereleases are not guaranteed to be backwards-compatible with
each other. For example, new API or ABI added in 2.25.1
might be removed or changed in 2.25.2.
If this would be a problem for you, please do not use prereleases.
* Only upgrade to a prerelease if you can guarantee that you will
promptly upgrade to the stable release that follows it.
For example, do not upgrade to 2.23.x unless you will be able to
upgrade to 2.24.0 when it becomes available.
* Software distributions that have a freeze policy (in particular Linux
distributions with a release cycle, such as Debian and Fedora)
should usually only package stable releases, and not prereleases.
## Before 2.23.0
Older versions of SDL followed a similar policy, but instead of the
odd/even rule applying to the minor version, it applied to the patchlevel
(micro version, third part). For example, 2.0.22 was a stable release
and 2.0.21 was a prerelease.
# Versioning
## Since 2.23.0
SDL follows an "odd/even" versioning policy, similar to GLib, GTK, Flatpak
and older versions of the Linux kernel:
* The major version (first part) increases when backwards compatibility
is broken, which will happen infrequently.
* If the minor version (second part) is divisible by 2
(for example 2.24.x, 2.26.x), this indicates a version of SDL that
is believed to be stable and suitable for production use.
* In stable releases, the patchlevel or micro version (third part)
indicates bugfix releases. Bugfix releases should not add or
remove ABI, so the ".0" release (for example 2.24.0) should be
forwards-compatible with all the bugfix releases from the
same cycle (for example 2.24.1).
* The minor version increases when new API or ABI is added, or when
other significant changes are made. Newer minor versions are
backwards-compatible, but not fully forwards-compatible.
For example, programs built against SDL 2.24.x should work fine
with SDL 2.26.x, but programs built against SDL 2.26.x will not
necessarily work with 2.24.x.
* If the minor version (second part) is not divisible by 2
(for example 2.23.x, 2.25.x), this indicates a development prerelease
of SDL that is not suitable for stable software distributions.
Use with caution.
* The patchlevel or micro version (third part) increases with
each prerelease.
* Each prerelease might add new API and/or ABI.
* Prereleases are backwards-compatible with older stable branches.
For example, 2.25.x will be backwards-compatible with 2.24.x.
* Prereleases are not guaranteed to be backwards-compatible with
each other. For example, new API or ABI added in 2.25.1
might be removed or changed in 2.25.2.
If this would be a problem for you, please do not use prereleases.
* Only upgrade to a prerelease if you can guarantee that you will
promptly upgrade to the stable release that follows it.
For example, do not upgrade to 2.23.x unless you will be able to
upgrade to 2.24.0 when it becomes available.
* Software distributions that have a freeze policy (in particular Linux
distributions with a release cycle, such as Debian and Fedora)
should usually only package stable releases, and not prereleases.
## Before 2.23.0
Older versions of SDL followed a similar policy, but instead of the
odd/even rule applying to the minor version, it applied to the patchlevel
(micro version, third part). For example, 2.0.22 was a stable release
and 2.0.21 was a prerelease.

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@ -1,113 +1,113 @@
Using SDL with Microsoft Visual C++
===================================
### by Lion Kimbro with additions by James Turk
You can either use the precompiled libraries from the [SDL](https://www.libsdl.org/download.php) web site, or you can build SDL
yourself.
### Building SDL
0. To build SDL, your machine must, at a minimum, have the DirectX9.0c SDK installed. It may or may not be retrievable from
the [Microsoft](https://www.microsoft.com) website, so you might need to locate it [online](https://duckduckgo.com/?q=directx9.0c+sdk+download&t=h_&ia=web).
_Editor's note: I've been able to successfully build SDL using Visual Studio 2019 **without** the DX9.0c SDK_
1. Open the Visual Studio solution file at `./VisualC/SDL.sln`.
2. Your IDE will likely prompt you to upgrade this solution file to whatever later version of the IDE you're using. In the `Retarget Projects` dialog,
all of the affected project files should be checked allowing you to use the latest `Windows SDK Version` you have installed, along with
the `Platform Toolset`.
If you choose *NOT* to upgrade to use the latest `Windows SDK Version` or `Platform Toolset`, then you'll need the `Visual Studio 2010 Platform Toolset`.
3. Build the `.dll` and `.lib` files by right clicking on each project in turn (Projects are listed in the _Workspace_
panel in the _FileView_ tab), and selecting `Build`.
You may get a few warnings, but you should not get any errors.
Later, we will refer to the following `.lib` and `.dll` files that have just been generated:
- `./VisualC/Win32/Debug/SDL3.dll` or `./VisualC/Win32/Release/SDL3.dll`
- `./VisualC/Win32/Debug/SDL3.lib` or `./VisualC/Win32/Release/SDL3.lib`
_Note for the `x64` versions, just replace `Win32` in the path with `x64`_
### Creating a Project with SDL
- Create a project as a `Win32 Application`.
- Create a C++ file for your project.
- Set the C runtime to `Multi-threaded DLL` in the menu:
`Project|Settings|C/C++ tab|Code Generation|Runtime Library `.
- Add the SDL `include` directory to your list of includes in the menu:
`Project|Settings|C/C++ tab|Preprocessor|Additional include directories `
*VC7 Specific: Instead of doing this, I find it easier to add the
include and library directories to the list that VC7 keeps. Do this by
selecting Tools|Options|Projects|VC++ Directories and under the "Show
Directories For:" dropbox select "Include Files", and click the "New
Directory Icon" and add the [SDLROOT]\\include directory (e.g. If you
installed to c:\\SDL\\ add c:\\SDL\\include). Proceed to change the
dropbox selection to "Library Files" and add [SDLROOT]\\lib.*
The "include directory" I am referring to is the `./include` folder.
Now we're going to use the files that we had created earlier in the *Build SDL* step.
Copy the following file into your Project directory:
- `SDL3.dll`
Add the following file to your project (It is not necessary to copy it to your project directory):
- `SDL3.lib`
To add them to your project, right click on your project, and select
`Add files to project`.
**Instead of adding the files to your project, it is more desirable to add them to the linker options: Project|Properties|Linker|Command Line
and type the names of the libraries to link with in the "Additional Options:" box. Note: This must be done for each build configuration
(e.g. Release,Debug).**
### Hello SDL
Here's a sample SDL snippet to verify everything is setup in your IDE:
```
#include <SDL3/SDL.h>
#include <SDL3/SDL_main.h> // only include this one in the source file with main()!
int main( int argc, char* argv[] )
{
const int WIDTH = 640;
const int HEIGHT = 480;
SDL_Window* window = NULL;
SDL_Renderer* renderer = NULL;
SDL_Init(SDL_INIT_VIDEO);
window = SDL_CreateWindow("Hello SDL", WIDTH, HEIGHT, 0);
renderer = SDL_CreateRenderer(window, NULL, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
```
### That's it!
I hope that this document has helped you get through the most difficult part of using the SDL: installing it.
Suggestions for improvements should be posted to the [Github Issues](https://github.com/libsdl-org/SDL/issues).
### Credits
Thanks to [Paulus Esterhazy](mailto:pesterhazy@gmx.net), for the work on VC++ port.
This document was originally called "VisualC.txt", and was written by [Sam Lantinga](mailto:slouken@libsdl.org).
Later, it was converted to HTML and expanded into the document that you see today by [Lion Kimbro](mailto:snowlion@sprynet.com).
Minor Fixes and Visual C++ 7 Information (In Green) was added by [James Turk](mailto:james@conceptofzero.net)
Using SDL with Microsoft Visual C++
===================================
### by Lion Kimbro with additions by James Turk
You can either use the precompiled libraries from the [SDL](https://www.libsdl.org/download.php) web site, or you can build SDL
yourself.
### Building SDL
0. To build SDL, your machine must, at a minimum, have the DirectX9.0c SDK installed. It may or may not be retrievable from
the [Microsoft](https://www.microsoft.com) website, so you might need to locate it [online](https://duckduckgo.com/?q=directx9.0c+sdk+download&t=h_&ia=web).
_Editor's note: I've been able to successfully build SDL using Visual Studio 2019 **without** the DX9.0c SDK_
1. Open the Visual Studio solution file at `./VisualC/SDL.sln`.
2. Your IDE will likely prompt you to upgrade this solution file to whatever later version of the IDE you're using. In the `Retarget Projects` dialog,
all of the affected project files should be checked allowing you to use the latest `Windows SDK Version` you have installed, along with
the `Platform Toolset`.
If you choose *NOT* to upgrade to use the latest `Windows SDK Version` or `Platform Toolset`, then you'll need the `Visual Studio 2010 Platform Toolset`.
3. Build the `.dll` and `.lib` files by right clicking on each project in turn (Projects are listed in the _Workspace_
panel in the _FileView_ tab), and selecting `Build`.
You may get a few warnings, but you should not get any errors.
Later, we will refer to the following `.lib` and `.dll` files that have just been generated:
- `./VisualC/Win32/Debug/SDL3.dll` or `./VisualC/Win32/Release/SDL3.dll`
- `./VisualC/Win32/Debug/SDL3.lib` or `./VisualC/Win32/Release/SDL3.lib`
_Note for the `x64` versions, just replace `Win32` in the path with `x64`_
### Creating a Project with SDL
- Create a project as a `Win32 Application`.
- Create a C++ file for your project.
- Set the C runtime to `Multi-threaded DLL` in the menu:
`Project|Settings|C/C++ tab|Code Generation|Runtime Library `.
- Add the SDL `include` directory to your list of includes in the menu:
`Project|Settings|C/C++ tab|Preprocessor|Additional include directories `
*VC7 Specific: Instead of doing this, I find it easier to add the
include and library directories to the list that VC7 keeps. Do this by
selecting Tools|Options|Projects|VC++ Directories and under the "Show
Directories For:" dropbox select "Include Files", and click the "New
Directory Icon" and add the [SDLROOT]\\include directory (e.g. If you
installed to c:\\SDL\\ add c:\\SDL\\include). Proceed to change the
dropbox selection to "Library Files" and add [SDLROOT]\\lib.*
The "include directory" I am referring to is the `./include` folder.
Now we're going to use the files that we had created earlier in the *Build SDL* step.
Copy the following file into your Project directory:
- `SDL3.dll`
Add the following file to your project (It is not necessary to copy it to your project directory):
- `SDL3.lib`
To add them to your project, right click on your project, and select
`Add files to project`.
**Instead of adding the files to your project, it is more desirable to add them to the linker options: Project|Properties|Linker|Command Line
and type the names of the libraries to link with in the "Additional Options:" box. Note: This must be done for each build configuration
(e.g. Release,Debug).**
### Hello SDL
Here's a sample SDL snippet to verify everything is setup in your IDE:
```
#include <SDL3/SDL.h>
#include <SDL3/SDL_main.h> // only include this one in the source file with main()!
int main( int argc, char* argv[] )
{
const int WIDTH = 640;
const int HEIGHT = 480;
SDL_Window* window = NULL;
SDL_Renderer* renderer = NULL;
SDL_Init(SDL_INIT_VIDEO);
window = SDL_CreateWindow("Hello SDL", WIDTH, HEIGHT, 0);
renderer = SDL_CreateRenderer(window, NULL, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
```
### That's it!
I hope that this document has helped you get through the most difficult part of using the SDL: installing it.
Suggestions for improvements should be posted to the [Github Issues](https://github.com/libsdl-org/SDL/issues).
### Credits
Thanks to [Paulus Esterhazy](mailto:pesterhazy@gmx.net), for the work on VC++ port.
This document was originally called "VisualC.txt", and was written by [Sam Lantinga](mailto:slouken@libsdl.org).
Later, it was converted to HTML and expanded into the document that you see today by [Lion Kimbro](mailto:snowlion@sprynet.com).
Minor Fixes and Visual C++ 7 Information (In Green) was added by [James Turk](mailto:james@conceptofzero.net)

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@ -1,33 +1,33 @@
PS Vita
=======
SDL port for the Sony Playstation Vita and Sony Playstation TV
Credit to
* xerpi, cpasjuste and rsn8887 for initial (vita2d) port
* vitasdk/dolcesdk devs
* CBPS discord (Namely Graphene and SonicMastr)
Building
--------
To build for the PSVita, make sure you have vitasdk and cmake installed and run:
```
cmake -S. -Bbuild -DCMAKE_TOOLCHAIN_FILE=${VITASDK}/share/vita.toolchain.cmake -DCMAKE_BUILD_TYPE=Release
cmake --build build
cmake --install build
```
Notes
-----
* gles1/gles2 support and renderers are disabled by default and can be enabled by configuring with `-DVIDEO_VITA_PVR=ON`
These renderers support 720p and 1080i resolutions. These can be specified with:
`SDL_setenv("VITA_RESOLUTION", "720", 1);` and `SDL_setenv("VITA_RESOLUTION", "1080", 1);`
* Desktop GL 1.X and 2.X support and renderers are also disabled by default and also can be enabled with `-DVIDEO_VITA_PVR=ON` as long as gl4es4vita is present in your SDK.
They support the same resolutions as the gles1/gles2 backends and require specifying `SDL_setenv("VITA_PVR_OGL", "1", 1);`
anytime before video subsystem initialization.
* gles2 support via PIB is disabled by default and can be enabled by configuring with `-DVIDEO_VITA_PIB=ON`
* By default SDL emits mouse events for touch events on every touchscreen.
Vita has two touchscreens, so it's recommended to use `SDL_SetHint(SDL_HINT_TOUCH_MOUSE_EVENTS, "0");` and handle touch events instead.
Individual touchscreens can be disabled with:
`SDL_setenv("VITA_DISABLE_TOUCH_FRONT", "1", 1);` and `SDL_setenv("VITA_DISABLE_TOUCH_BACK", "1", 1);`
* Support for L2/R2/R3/R3 buttons, haptic feedback and gamepad led only available on PSTV, or when using external ds4 gamepad on vita.
PS Vita
=======
SDL port for the Sony Playstation Vita and Sony Playstation TV
Credit to
* xerpi, cpasjuste and rsn8887 for initial (vita2d) port
* vitasdk/dolcesdk devs
* CBPS discord (Namely Graphene and SonicMastr)
Building
--------
To build for the PSVita, make sure you have vitasdk and cmake installed and run:
```
cmake -S. -Bbuild -DCMAKE_TOOLCHAIN_FILE=${VITASDK}/share/vita.toolchain.cmake -DCMAKE_BUILD_TYPE=Release
cmake --build build
cmake --install build
```
Notes
-----
* gles1/gles2 support and renderers are disabled by default and can be enabled by configuring with `-DVIDEO_VITA_PVR=ON`
These renderers support 720p and 1080i resolutions. These can be specified with:
`SDL_setenv("VITA_RESOLUTION", "720", 1);` and `SDL_setenv("VITA_RESOLUTION", "1080", 1);`
* Desktop GL 1.X and 2.X support and renderers are also disabled by default and also can be enabled with `-DVIDEO_VITA_PVR=ON` as long as gl4es4vita is present in your SDK.
They support the same resolutions as the gles1/gles2 backends and require specifying `SDL_setenv("VITA_PVR_OGL", "1", 1);`
anytime before video subsystem initialization.
* gles2 support via PIB is disabled by default and can be enabled by configuring with `-DVIDEO_VITA_PIB=ON`
* By default SDL emits mouse events for touch events on every touchscreen.
Vita has two touchscreens, so it's recommended to use `SDL_SetHint(SDL_HINT_TOUCH_MOUSE_EVENTS, "0");` and handle touch events instead.
Individual touchscreens can be disabled with:
`SDL_setenv("VITA_DISABLE_TOUCH_FRONT", "1", 1);` and `SDL_setenv("VITA_DISABLE_TOUCH_BACK", "1", 1);`
* Support for L2/R2/R3/R3 buttons, haptic feedback and gamepad led only available on PSTV, or when using external ds4 gamepad on vita.

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Wayland
=======
Wayland is a replacement for the X11 window system protocol and architecture and is favored over X11 by default in SDL3
for communicating with desktop compositors. It works well for the majority of applications, however, applications may
encounter limitations or behavior that is different from other windowing systems.
## Common issues:
### Window decorations are missing, or the decorations look strange
- On some desktops (i.e. GNOME), Wayland applications use a library
called [libdecor](https://gitlab.freedesktop.org/libdecor/libdecor) to provide window decorations. If this library is
not installed, the decorations will be missing. This library uses plugins to generate different decoration styles, and
if a plugin to generate native-looking decorations is not installed (i.e. the GTK plugin), the decorations will not
appear to be 'native'.
### Windows do not appear immediately after creation
- Wayland requires that the application initially present a buffer before the window becomes visible. Additionally,
applications _must_ have an event loop and processes messages on a regular basis, or the application can appear
unresponsive to both the user and desktop compositor.
### ```SDL_SetWindowPosition()``` doesn't work on non-popup windows
- Wayland does not allow toplevel windows to position themselves programmatically.
### Retrieving the global mouse cursor position when the cursor is outside a window doesn't work
- Wayland only provides applications with the cursor position within the borders of the application windows. Querying
the global position when an application window does not have mouse focus returns 0,0 as the actual cursor position is
unknown. In most cases, applications don't actually need the global cursor position and should use the window-relative
coordinates as provided by the mouse movement event or from ```SDL_GetMouseState()``` instead.
### Warping the global mouse cursor position via ```SDL_WarpMouseGlobal()``` doesn't work
- For security reasons, Wayland does not allow warping the global mouse cursor position.
### The application icon can't be set via ```SDL_SetWindowIcon()```
- Wayland doesn't support programmatically setting the application icon. To provide a custom icon for your application,
you must create an associated desktop entry file, aka a `.desktop` file, that points to the icon image. Please see the
[Desktop Entry Specification](https://specifications.freedesktop.org/desktop-entry-spec/latest/) for more information
on the format of this file. Note that if your application manually sets the application ID via the `SDL_APP_ID` hint
string, the desktop entry file name should match the application ID. For example, if your application ID is set
to `org.my_org.sdl_app`, the desktop entry file should be named `org.my_org.sdl_app.desktop`.
Wayland
=======
Wayland is a replacement for the X11 window system protocol and architecture and is favored over X11 by default in SDL3
for communicating with desktop compositors. It works well for the majority of applications, however, applications may
encounter limitations or behavior that is different from other windowing systems.
## Common issues:
### Window decorations are missing, or the decorations look strange
- On some desktops (i.e. GNOME), Wayland applications use a library
called [libdecor](https://gitlab.freedesktop.org/libdecor/libdecor) to provide window decorations. If this library is
not installed, the decorations will be missing. This library uses plugins to generate different decoration styles, and
if a plugin to generate native-looking decorations is not installed (i.e. the GTK plugin), the decorations will not
appear to be 'native'.
### Windows do not appear immediately after creation
- Wayland requires that the application initially present a buffer before the window becomes visible. Additionally,
applications _must_ have an event loop and processes messages on a regular basis, or the application can appear
unresponsive to both the user and desktop compositor.
### ```SDL_SetWindowPosition()``` doesn't work on non-popup windows
- Wayland does not allow toplevel windows to position themselves programmatically.
### Retrieving the global mouse cursor position when the cursor is outside a window doesn't work
- Wayland only provides applications with the cursor position within the borders of the application windows. Querying
the global position when an application window does not have mouse focus returns 0,0 as the actual cursor position is
unknown. In most cases, applications don't actually need the global cursor position and should use the window-relative
coordinates as provided by the mouse movement event or from ```SDL_GetMouseState()``` instead.
### Warping the global mouse cursor position via ```SDL_WarpMouseGlobal()``` doesn't work
- For security reasons, Wayland does not allow warping the global mouse cursor position.
### The application icon can't be set via ```SDL_SetWindowIcon()```
- Wayland doesn't support programmatically setting the application icon. To provide a custom icon for your application,
you must create an associated desktop entry file, aka a `.desktop` file, that points to the icon image. Please see the
[Desktop Entry Specification](https://specifications.freedesktop.org/desktop-entry-spec/latest/) for more information
on the format of this file. Note that if your application manually sets the application ID via the `SDL_APP_ID` hint
string, the desktop entry file name should match the application ID. For example, if your application ID is set
to `org.my_org.sdl_app`, the desktop entry file should be named `org.my_org.sdl_app.desktop`.

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# Windows
## LLVM and Intel C++ compiler support
SDL will build with the Visual Studio project files with LLVM-based compilers, such as the Intel oneAPI C++
compiler, but you'll have to manually add the "-msse3" command line option
to at least the SDL_audiocvt.c source file, and possibly others. This may
not be necessary if you build SDL with CMake instead of the included Visual
Studio solution.
Details are here: https://github.com/libsdl-org/SDL/issues/5186
## OpenGL ES 2.x support
SDL has support for OpenGL ES 2.x under Windows via two alternative
implementations.
The most straightforward method consists in running your app in a system with
a graphic card paired with a relatively recent (as of November of 2013) driver
which supports the WGL_EXT_create_context_es2_profile extension. Vendors known
to ship said extension on Windows currently include nVidia and Intel.
The other method involves using the
[ANGLE library](https://code.google.com/p/angleproject/). If an OpenGL ES 2.x
context is requested and no WGL_EXT_create_context_es2_profile extension is
found, SDL will try to load the libEGL.dll library provided by ANGLE.
To obtain the ANGLE binaries, you can either compile from source from
https://chromium.googlesource.com/angle/angle or copy the relevant binaries
from a recent Chrome/Chromium install for Windows. The files you need are:
- libEGL.dll
- libGLESv2.dll
- d3dcompiler_46.dll (supports Windows Vista or later, better shader
compiler) *or* d3dcompiler_43.dll (supports Windows XP or later)
If you compile ANGLE from source, you can configure it so it does not need the
d3dcompiler_* DLL at all (for details on this, see their documentation).
However, by default SDL will try to preload the d3dcompiler_46.dll to
comply with ANGLE's requirements. If you wish SDL to preload
d3dcompiler_43.dll (to support Windows XP) or to skip this step at all, you
can use the SDL_HINT_VIDEO_WIN_D3DCOMPILER hint (see SDL_hints.h for more
details).
Known Bugs:
- SDL_GL_SetSwapInterval is currently a no op when using ANGLE. It appears
that there's a bug in the library which prevents the window contents from
refreshing if this is set to anything other than the default value.
## Vulkan Surface Support
Support for creating Vulkan surfaces is configured on by default. To disable
it change the value of `SDL_VIDEO_VULKAN` to 0 in `SDL_config_windows.h`. You
must install the [Vulkan SDK](https://www.lunarg.com/vulkan-sdk/) in order to
use Vulkan graphics in your application.
## Transparent Window Support
SDL uses the Desktop Window Manager (DWM) to create transparent windows. DWM is
always enabled from Windows 8 and above. Windows 7 only enables DWM with Aero Glass
theme.
However, it cannot be guaranteed to work on all hardware configurations (an example
is hybrid GPU systems, such as NVIDIA Optimus laptops).
# Windows
## LLVM and Intel C++ compiler support
SDL will build with the Visual Studio project files with LLVM-based compilers, such as the Intel oneAPI C++
compiler, but you'll have to manually add the "-msse3" command line option
to at least the SDL_audiocvt.c source file, and possibly others. This may
not be necessary if you build SDL with CMake instead of the included Visual
Studio solution.
Details are here: https://github.com/libsdl-org/SDL/issues/5186
## OpenGL ES 2.x support
SDL has support for OpenGL ES 2.x under Windows via two alternative
implementations.
The most straightforward method consists in running your app in a system with
a graphic card paired with a relatively recent (as of November of 2013) driver
which supports the WGL_EXT_create_context_es2_profile extension. Vendors known
to ship said extension on Windows currently include nVidia and Intel.
The other method involves using the
[ANGLE library](https://code.google.com/p/angleproject/). If an OpenGL ES 2.x
context is requested and no WGL_EXT_create_context_es2_profile extension is
found, SDL will try to load the libEGL.dll library provided by ANGLE.
To obtain the ANGLE binaries, you can either compile from source from
https://chromium.googlesource.com/angle/angle or copy the relevant binaries
from a recent Chrome/Chromium install for Windows. The files you need are:
- libEGL.dll
- libGLESv2.dll
- d3dcompiler_46.dll (supports Windows Vista or later, better shader
compiler) *or* d3dcompiler_43.dll (supports Windows XP or later)
If you compile ANGLE from source, you can configure it so it does not need the
d3dcompiler_* DLL at all (for details on this, see their documentation).
However, by default SDL will try to preload the d3dcompiler_46.dll to
comply with ANGLE's requirements. If you wish SDL to preload
d3dcompiler_43.dll (to support Windows XP) or to skip this step at all, you
can use the SDL_HINT_VIDEO_WIN_D3DCOMPILER hint (see SDL_hints.h for more
details).
Known Bugs:
- SDL_GL_SetSwapInterval is currently a no op when using ANGLE. It appears
that there's a bug in the library which prevents the window contents from
refreshing if this is set to anything other than the default value.
## Vulkan Surface Support
Support for creating Vulkan surfaces is configured on by default. To disable
it change the value of `SDL_VIDEO_VULKAN` to 0 in `SDL_config_windows.h`. You
must install the [Vulkan SDK](https://www.lunarg.com/vulkan-sdk/) in order to
use Vulkan graphics in your application.
## Transparent Window Support
SDL uses the Desktop Window Manager (DWM) to create transparent windows. DWM is
always enabled from Windows 8 and above. Windows 7 only enables DWM with Aero Glass
theme.
However, it cannot be guaranteed to work on all hardware configurations (an example
is hybrid GPU systems, such as NVIDIA Optimus laptops).

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# Simple DirectMedia Layer
https://www.libsdl.org/
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
SDL officially supports Windows, macOS, Linux, iOS, and Android.
Support for other platforms may be found in the source code.
SDL is written in C, works natively with C++, and there are bindings
available for several other languages, including C# and Python.
This library is distributed under the zlib license, which can be found
in the file "LICENSE.txt".
The best way to learn how to use SDL is to check out the header files in
the "include" subdirectory and the programs in the "test" subdirectory.
The header files and test programs are well commented and always up to date.
More documentation and FAQs are available online at [the wiki](http://wiki.libsdl.org/)
- [Android](README-android.md)
- [CMake](README-cmake.md)
- [DynAPI](README-dynapi.md)
- [Emscripten](README-emscripten.md)
- [GDK](README-gdk.md)
- [Git](README-git.md)
- [iOS](README-ios.md)
- [Linux](README-linux.md)
- [macOS](README-macos.md)
- [Supported Platforms](README-platforms.md)
- [Porting information](README-porting.md)
- [PSP](README-psp.md)
- [PS2](README-ps2.md)
- [Raspberry Pi](README-raspberrypi.md)
- [Touch](README-touch.md)
- [Versions](README-versions.md)
- [Windows](README-windows.md)
- [WinRT](README-winrt.md)
- [PSVita](README-vita.md)
- [Nokia N-Gage](README-ngage.md)
If you need help with the library, or just want to discuss SDL related
issues, you can join the [SDL Discourse](https://discourse.libsdl.org/),
which can be used as a web forum or a mailing list, at your preference.
If you want to report bugs or contribute patches, please submit them to
[our bug tracker](https://github.com/libsdl-org/SDL/issues)
Enjoy!
Sam Lantinga <mailto:slouken@libsdl.org>
# Simple DirectMedia Layer
https://www.libsdl.org/
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
SDL officially supports Windows, macOS, Linux, iOS, and Android.
Support for other platforms may be found in the source code.
SDL is written in C, works natively with C++, and there are bindings
available for several other languages, including C# and Python.
This library is distributed under the zlib license, which can be found
in the file "LICENSE.txt".
The best way to learn how to use SDL is to check out the header files in
the "include" subdirectory and the programs in the "test" subdirectory.
The header files and test programs are well commented and always up to date.
More documentation and FAQs are available online at [the wiki](http://wiki.libsdl.org/)
- [Android](README-android.md)
- [CMake](README-cmake.md)
- [DynAPI](README-dynapi.md)
- [Emscripten](README-emscripten.md)
- [GDK](README-gdk.md)
- [Git](README-git.md)
- [iOS](README-ios.md)
- [Linux](README-linux.md)
- [macOS](README-macos.md)
- [Supported Platforms](README-platforms.md)
- [Porting information](README-porting.md)
- [PSP](README-psp.md)
- [PS2](README-ps2.md)
- [Raspberry Pi](README-raspberrypi.md)
- [Touch](README-touch.md)
- [Versions](README-versions.md)
- [Windows](README-windows.md)
- [WinRT](README-winrt.md)
- [PSVita](README-vita.md)
- [Nokia N-Gage](README-ngage.md)
If you need help with the library, or just want to discuss SDL related
issues, you can join the [SDL Discourse](https://discourse.libsdl.org/),
which can be used as a web forum or a mailing list, at your preference.
If you want to report bugs or contribute patches, please submit them to
[our bug tracker](https://github.com/libsdl-org/SDL/issues)
Enjoy!
Sam Lantinga <mailto:slouken@libsdl.org>