--- /dev/null
+/*
+ * Test sharing of texture objects by two rendering contexts.
+ * In particular, test that changing a texture object in one context
+ * effects the texture in the second context.
+ *
+ * Brian Paul
+ * 30 Apr 2008
+ *
+ * Copyright (C) 2008 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.
+ */
+
+
+#include <GL/gl.h>
+#include <GL/glx.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <X11/keysym.h>
+
+
+#define MAX_CONTEXTS 2
+
+#define TEX_SIZE 32
+
+static const char *DisplayName = NULL;
+static Display *Dpy;
+static XVisualInfo *VisInfo;
+static Window Win;
+static GLXContext Contexts[MAX_CONTEXTS];
+static int WinWidth = 300, WinHeight = 300;
+
+static int DrawContext = 0, TexContext = 1;
+
+static GLuint TexObj = 0;
+static GLboolean NewTexture = GL_FALSE;
+
+
+static void
+Error(const char *msg)
+{
+ fprintf(stderr, "sharedtex error: %s\n", msg);
+ exit(1);
+}
+
+
+static void
+CreateWindow(const char *name)
+{
+ int attrib[] = { GLX_RGBA,
+ GLX_RED_SIZE, 1,
+ GLX_GREEN_SIZE, 1,
+ GLX_BLUE_SIZE, 1,
+ GLX_DOUBLEBUFFER,
+ None };
+ int scrnum;
+ XSetWindowAttributes attr;
+ unsigned long mask;
+ Window root;
+ int xpos = 0, ypos = 0;
+ static int n = 0;
+
+ scrnum = DefaultScreen(Dpy);
+ root = RootWindow(Dpy, scrnum);
+
+ VisInfo = glXChooseVisual(Dpy, scrnum, attrib);
+ if (!VisInfo) {
+ Error("Unable to find RGB, double-buffered visual");
+ }
+
+ /* window attributes */
+ xpos = (n % 10) * 100;
+ ypos = (n / 10) * 100;
+ n++;
+
+ 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, WinWidth, WinHeight,
+ 0, VisInfo->depth, InputOutput,
+ VisInfo->visual, mask, &attr);
+ if (!Win) {
+ Error("Couldn't create window");
+ }
+
+ {
+ XSizeHints sizehints;
+ sizehints.x = xpos;
+ sizehints.y = ypos;
+ sizehints.width = WinWidth;
+ sizehints.height = WinHeight;
+ sizehints.flags = USSize | USPosition;
+ XSetNormalHints(Dpy, Win, &sizehints);
+ XSetStandardProperties(Dpy, Win, name, name,
+ None, (char **)NULL, 0, &sizehints);
+ }
+
+ XMapWindow(Dpy, Win);
+}
+
+
+/**
+ * Change texture image, using TexContext
+ */
+static void
+ModifyTexture(void)
+{
+ GLuint tex[TEX_SIZE][TEX_SIZE];
+ GLuint c0, c1;
+ int i, j;
+
+ if (Win && !glXMakeCurrent(Dpy, Win, Contexts[TexContext])) {
+ Error("glXMakeCurrent failed");
+ }
+
+ /* choose two random colors */
+ c0 = rand() & 0xffffffff;
+ c1 = rand() & 0xffffffff;
+
+ for (i = 0; i < TEX_SIZE; i++) {
+ for (j = 0; j < TEX_SIZE; j++) {
+ if (((i / 4) ^ (j / 4)) & 1) {
+ tex[i][j] = c0;
+ }
+ else {
+ tex[i][j] = c1;
+ }
+ }
+ }
+
+ glBindTexture(GL_TEXTURE_2D, TexObj);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, TEX_SIZE, TEX_SIZE, 0,
+ GL_RGBA, GL_UNSIGNED_BYTE, tex);
+
+ NewTexture = GL_TRUE;
+}
+
+
+static void
+InitContext(void)
+{
+ glGenTextures(1, &TexObj);
+ assert(TexObj);
+ glBindTexture(GL_TEXTURE_2D, TexObj);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+ glEnable(GL_TEXTURE_2D);
+
+ printf("GL_RENDERER = %s\n", (char*) glGetString(GL_RENDERER));
+}
+
+
+static void
+Setup(void)
+{
+ int i;
+
+ Dpy = XOpenDisplay(DisplayName);
+ if (!Dpy) {
+ Error("Unable to open display");
+ }
+
+ CreateWindow("sharedtex");
+
+ for (i = 0; i < MAX_CONTEXTS; i++) {
+ GLXContext share = i > 0 ? Contexts[0] : 0;
+
+ Contexts[i] = glXCreateContext(Dpy, VisInfo, share, True);
+ if (!Contexts[i]) {
+ Error("Unable to create GLX context");
+ }
+
+ if (!glXMakeCurrent(Dpy, Win, Contexts[i])) {
+ Error("glXMakeCurrent failed");
+ }
+
+ InitContext();
+ }
+
+ ModifyTexture();
+}
+
+
+/**
+ * Redraw window, using DrawContext
+ */
+static void
+Redraw(void)
+{
+ static float rot = 0.0;
+ float ar;
+
+ rot += 1.0;
+
+ if (Win && !glXMakeCurrent(Dpy, Win, Contexts[DrawContext])) {
+ Error("glXMakeCurrent failed");
+ }
+
+ glViewport(0, 0, WinWidth, WinHeight);
+ ar = (float) WinWidth / (float) WinHeight;
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(-ar, ar, -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);
+
+ glPushMatrix();
+ glRotatef(rot, 0, 0, 1);
+ glScalef(0.7, 0.7, 0.7);
+
+ if (NewTexture) {
+ /* rebind to get new contents */
+ glBindTexture(GL_TEXTURE_2D, TexObj);
+ NewTexture = GL_FALSE;
+ }
+
+ /* draw textured quad */
+ glBegin(GL_POLYGON);
+ glTexCoord2f( 0.0, 0.0 ); glVertex2f( -1.0, -1.0 );
+ glTexCoord2f( 1.0, 0.0 ); glVertex2f( 1.0, -1.0 );
+ glTexCoord2f( 1.0, 1.0 ); glVertex2f( 1.0, 1.0 );
+ glTexCoord2f( 0.0, 1.0 ); glVertex2f( -1.0, 1.0 );
+ glEnd();
+
+ glPopMatrix();
+
+ if (Win)
+ glXSwapBuffers(Dpy, Win);
+}
+
+
+static void
+EventLoop(void)
+{
+ while (1) {
+ while (XPending(Dpy) > 0) {
+ XEvent event;
+ XNextEvent(Dpy, &event);
+
+ switch (event.type) {
+ case Expose:
+ Redraw();
+ break;
+ case ConfigureNotify:
+ WinWidth = event.xconfigure.width;
+ WinHeight = event.xconfigure.height;
+ break;
+ case KeyPress:
+ {
+ char buf[100];
+ KeySym keySym;
+ XComposeStatus stat;
+ XLookupString(&event.xkey, buf, sizeof(buf), &keySym, &stat);
+ switch (keySym) {
+ case XK_Escape:
+ exit(0);
+ break;
+ case XK_t:
+ case XK_T:
+ ModifyTexture();
+ break;
+ default:
+ ;
+ }
+ }
+ Redraw();
+ break;
+ default:
+ /*no-op*/ ;
+ }
+ }
+
+ Redraw();
+ usleep(10000);
+ }
+}
+
+
+
+
+int
+main(int argc, char *argv[])
+{
+ int i;
+
+ for (i = 1; i < argc; i++) {
+ if (strcmp(argv[i], "-display") == 0 && i < argc) {
+ DisplayName = argv[i+1];
+ i++;
+ }
+ }
+
+ Setup();
+
+ printf("Press 't' to change texture image/colors\n");
+
+ EventLoop();
+
+ return 0;
+}