added xdemos/sharedtex.c test

Test that modifications to a texture object in one rendering context are seen
in a second rendering context.
Press 't' to change the texture's image/colors.

progs/xdemos/Makefile

@@ -23,6 +23,7 @@ PROGS = glthreads \
 	overlay \
 	pbinfo \
 	pbdemo \
+	sharedtex \
 	texture_from_pixmap \
 	wincopy \
 	xfont \

progs/xdemos/sharedtex.c

@@ -0,0 +1,324 @@
+/*
+ * 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;
+}