mesa/progs/xdemos/wincopy.c
2004-03-26 14:17:31 +00:00

312 lines
7.4 KiB
C

/*
* Mesa 3-D graphics library
* Version: 6.1
*
* Copyright (C) 1999-2004 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/*
* This program opens two GLX windows, renders into one and uses
* glCopyPixels to copy the image from the first window into the
* second by means of the GLX 1.3 function glxMakeContextCurrent().
* This function works just like the glXMakeCurrentReadSGI() function
* in the GLX_SGI_make_current_read extension.
*/
#include <GL/gl.h>
#include <GL/glx.h>
#include <X11/keysym.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifdef GLX_VERSION_1_3
static Display *Dpy;
static int ScrNum;
static GLXContext Context;
static Window Win[2]; /* Win[0] = source, Win[1] = dest */
static GLint Width[2], Height[2];
static GLfloat Angle = 0.0;
static GLboolean DrawFront = GL_FALSE;
static Window
CreateWindow(Display *dpy, int scrnum, XVisualInfo *visinfo,
int xpos, int ypos, int width, int height,
const char *name)
{
Window win;
XSetWindowAttributes attr;
unsigned long mask;
Window root;
root = RootWindow(dpy, scrnum);
/* window attributes */
attr.background_pixel = 0;
attr.border_pixel = 0;
attr.colormap = XCreateColormap(dpy, root, visinfo->visual, AllocNone);
attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
win = XCreateWindow(dpy, root, xpos, ypos, width, height,
0, visinfo->depth, InputOutput,
visinfo->visual, mask, &attr);
if (win) {
XSizeHints sizehints;
sizehints.x = xpos;
sizehints.y = ypos;
sizehints.width = width;
sizehints.height = height;
sizehints.flags = USSize | USPosition;
XSetNormalHints(dpy, win, &sizehints);
XSetStandardProperties(dpy, win, name, name,
None, (char **)NULL, 0, &sizehints);
XMapWindow(dpy, win);
}
return win;
}
static void
Redraw(void)
{
/* make the first window the current one */
if (!glXMakeContextCurrent(Dpy, Win[0], Win[0], Context)) {
printf("glXMakeContextCurrent failed in Redraw()\n");
return;
}
Angle += 1.0;
if (DrawFront) {
glDrawBuffer(GL_FRONT);
glReadBuffer(GL_FRONT);
}
else {
glDrawBuffer(GL_BACK);
glReadBuffer(GL_BACK);
}
glViewport(0, 0, Width[0], Height[0]);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
glMatrixMode(GL_MODELVIEW);
glShadeModel(GL_FLAT);
glClearColor(0.5, 0.5, 0.5, 1.0);
glClear(GL_COLOR_BUFFER_BIT);
/* draw blue quad */
glColor3f(0.3, 0.3, 1.0);
glPushMatrix();
glRotatef(Angle, 0, 0, 1);
glBegin(GL_POLYGON);
glVertex2f(-0.5, -0.25);
glVertex2f( 0.5, -0.25);
glVertex2f( 0.5, 0.25);
glVertex2f(-0.5, 0.25);
glEnd();
glPopMatrix();
if (DrawFront)
glFinish();
else
glXSwapBuffers(Dpy, Win[0]);
/* copy image from window 0 to window 1 */
if (!glXMakeContextCurrent(Dpy, Win[1], Win[0], Context)) {
printf("glXMakeContextCurrent failed in Redraw()\n");
return;
}
/* raster pos setup */
glViewport(0, 0, Width[1], Height[1]);
glPushMatrix();
glLoadIdentity();
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
glOrtho(-1, 1, -1, 1, -1, 1);
glRasterPos2f(-1, -1);
/* copy the image between windows */
glCopyPixels(0, 0, Width[0], Height[0], GL_COLOR);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
glPopMatrix();
if (DrawFront)
glFinish();
else
glXSwapBuffers(Dpy, Win[1]);
}
static void
Resize(Window win, unsigned int width, unsigned int height)
{
int i;
if (win == Win[0]) {
i = 0;
}
else {
i = 1;
}
Width[i] = width;
Height[i] = height;
if (!glXMakeCurrent(Dpy, Win[i], Context)) {
printf("glXMakeCurrent failed in Resize()\n");
return;
}
}
static void
EventLoop(void)
{
XEvent event;
while (1) {
if (XPending(Dpy) > 0) {
XNextEvent( Dpy, &event );
switch (event.type) {
case Expose:
Redraw();
break;
case ConfigureNotify:
Resize(event.xany.window, event.xconfigure.width, event.xconfigure.height);
break;
case KeyPress:
{
char buf[100];
KeySym keySym;
XComposeStatus stat;
XLookupString(&event.xkey, buf, sizeof(buf), &keySym, &stat);
if (keySym == XK_Escape) {
/* exit */
return;
}
else if (buf[0] == 'f') {
DrawFront = !DrawFront;
printf("Drawing to %s buffer\n",
DrawFront ? "GL_FRONT" : "GL_BACK");
}
}
break;
default:
/*no-op*/ ;
}
}
else {
/* animate */
Redraw();
}
}
}
static void
Init(void)
{
XVisualInfo *visinfo;
int attrib[] = { GLX_RGBA,
GLX_RED_SIZE, 1,
GLX_GREEN_SIZE, 1,
GLX_BLUE_SIZE, 1,
GLX_DOUBLEBUFFER,
None };
int major, minor;
Dpy = XOpenDisplay(NULL);
if (!Dpy) {
printf("Couldn't open default display!\n");
exit(1);
}
ScrNum = DefaultScreen(Dpy);
glXQueryVersion(Dpy, &major, &minor);
if (major * 100 + minor < 103) {
fprintf(stderr, "Sorry, this program requires GLX 1.3\n");
exit(1);
}
visinfo = glXChooseVisual(Dpy, ScrNum, attrib);
if (!visinfo) {
printf("Unable to find RGB, double-buffered visual\n");
exit(1);
}
Context = glXCreateContext(Dpy, visinfo, NULL, True);
if (!Context) {
printf("Couldn't create GLX context\n");
exit(1);
}
Win[0] = CreateWindow(Dpy, ScrNum, visinfo,
0, 0, 300, 300, "source window");
Win[1] = CreateWindow(Dpy, ScrNum, visinfo,
350, 0, 300, 300, "dest window");
printf("Press Esc to exit\n");
printf("Press 'f' to toggle front/back buffer drawing\n");
}
int
main(int argc, char *argv[])
{
Init();
EventLoop();
return 0;
}
#else
int
main(int argc, char *argv[])
{
printf("This program requires GLX 1.3!\n");
return 0;
}
#endif /* GLX_VERSION_1_3 */