--- /dev/null
+/* $Id: wincopy.c,v 1.1 1999/11/25 17:41:51 brianp Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.3
+ *
+ * Copyright (C) 1999 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 <stdio.h>
+#include <stdlib.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 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;
+
+ 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();
+
+ 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 */
+ glDrawBuffer(GL_FRONT);
+ glCopyPixels(0, 0, Width[0], Height[0], GL_COLOR);
+ glDrawBuffer(GL_BACK);
+
+ glPopMatrix();
+ glMatrixMode(GL_MODELVIEW);
+ glPopMatrix();
+}
+
+
+
+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:
+ return;
+ 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 };
+
+ Dpy = XOpenDisplay(NULL);
+ if (!Dpy) {
+ printf("Couldn't open default display!\n");
+ exit(1);
+ }
+
+ ScrNum = DefaultScreen(Dpy);
+
+ 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");
+
+}
+
+
+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 */