Littlev Graphics Libraray

LittlevGL provides everything you need to create a Graphical User Interface (GUI) on embedded systems with easy-to-use graphical elements, beautiful visual effects and low memory footprint.

Homepage: http://www.gl.littlev.hu

Table Of Content

Key features
Porting
Project set-up
PC simulator
Screenshots
Contributing
Donate

Key features

Powerful building blocks buttons, charts, lists, sliders, images etc
Advanced graphics with animations, anti-aliasing, opacity, smooth scrolling
Various input devices touch pad, mouse, keyboard and external buttons
Multi language support with UTF-8 support
Fully customizable graphical elements
Hardware independent to use with any microcontroller or display
Scalable to operate with few memory (80 kB Flash, 10 kB RAM)
OS, External memory and GPU supported but not required
Single frame buffer operation even with advances graphical effects
Written in C for maximal compatibility
PC simulator to develop without embedded hardware
Tutorials, examples, themes for rapid development
Advanced support and professional GUI development service
Documentation and API references online
Free and open source under MIT licence

Porting

In the most sime case you need 4 things:

Call lv_tick_inc(1) in every millisecods in a Timer or Task
Register a function which can copy a pixel array to an area of the screen
Register a function which can read an input device. (E.g. touch pad)
Call lv_task_handler() periodically in every few milliseconds ()

For more information visit http://www.gl.littlev.hu/porting

Project set-up

Clone or download the lvgl repository: git clone https://github.com/littlevgl/lvgl.git
Create project with your prefered IDE and add the lvgl folder
Copy lvgl/lv_conf_templ.h as lv_conf.h next to the lvgl folder
In the *_conf.h files delete the first #if 0 and its #endif. Let the default configurations at first.
In your main.c: #include "lvgl/lvgl.h"
In your main function:
- lvgl_init();
- tick, display and input device initialization (see above)
To test create a label: lv_obj_t * label = lv_label_create(lv_scr_act(), NULL);
In the main while(1) call lv_task_handler(); and make a few milliseconds delay (e.g. my_delay_ms(5);)
Compile the code and load it to your embedded hardware

PC Simulator

If you don't have got an embedded hardware you can test the graphics library in a PC simulator. The simulator uses SDL2 to emulate a display on your monitor and a touch pad with your mouse.

There is a pre-configured PC project for Eclipse CDT in this repository: https://github.com/littlevgl/pc_simulator