progs/tests/jkrahntest.c

   1
   2 /* This is a good test for glXSwapBuffers on non-current windows,
   3  * and the glXCopyContext function.  Fixed several Mesa/DRI bugs with
   4  * this program on 15 June 2002.
   5  *
   6  * Joe's comments follow:
   7  *
   8  * I have tried some different approaches for being able to
   9  * draw to multiple windows using one context, or a copied
  10  * context. Mesa/indirect rendering works to use one context
  11  * for multiple windows, but crashes with glXCopyContext.
  12  * DRI is badly broken, at least for ATI.
  13  *
  14  * I also noticed that glXMakeCurrent allows a window and context
  15  * from different visuals to be attached (haven't tested recently).
  16  *
  17  * Joe Krahn  <jkrahn@nc.rr.com>
  18  */
  19
  20 #include <GL/glx.h>
  21 #include <GL/gl.h>
  22 #include <string.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <math.h>
  27
  28 #ifndef M_PI
  29 #define M_PI 3.14159
  30 #endif
  31
  32 #define DEGTOR (M_PI/180.0)
  33
  34 static int AttributeList[] = { GLX_RGBA, GLX_DOUBLEBUFFER, None };
  35
  36 int main(int argc, char **argv)
  37 {
  38     Window win1, win2;
  39     XVisualInfo *vi;
  40     XSetWindowAttributes swa;
  41     Display *dpy;
  42     GLXContext ctx1, ctx2;
  43     float angle;
  44     int test;
  45
  46     if (argc < 2) {
  47        fprintf(stderr, "This program tests GLX context switching.\n");
  48        fprintf(stderr, "Usage: jkrahntest <n>\n");
  49        fprintf(stderr, "Where n is:\n");
  50        fprintf(stderr, "\t1) Use two contexts and swap only when the context is current (typical case).\n");
  51        fprintf(stderr, "\t2) Use two contexts and swap at the same time.\n");
  52        fprintf(stderr, "\t\t Used to crash Mesa & nVidia, and DRI artifacts. Seems OK now.\n");
  53        fprintf(stderr, "\t3) Use one context, but only swap when a context is current.\n");
  54        fprintf(stderr, "\t\t Serious artifacts for DRI at least with ATI.\n");
  55        fprintf(stderr, "\t4) Use one context, swap both windows at the same time, so the left\n");
  56        fprintf(stderr, "\t\t window has no context at swap time. Severe artifacts for DRI.\n");
  57        fprintf(stderr, "\t5) Use two contexts, copying one to the other when switching windows.\n");
  58        fprintf(stderr, "\t\t DRI gives an error, indirect rendering crashes server.\n");
  59
  60         exit(1);
  61     }
  62     test = atoi(argv[1]);
  63
  64     /* get a connection */
  65     dpy = XOpenDisplay(NULL);
  66
  67     /* Get an appropriate visual */
  68     vi = glXChooseVisual(dpy, DefaultScreen(dpy), AttributeList);
  69     if (vi == 0) {
  70         fprintf(stderr, "No matching visuals found.\n");
  71         exit(-1);
  72     }
  73
  74     /* Create two GLX contexts, with list sharing */
  75     ctx1 = glXCreateContext(dpy, vi, 0, True);
  76     ctx2 = glXCreateContext(dpy, vi, ctx1, True);
  77
  78     /* create a colormap */
  79     swa.colormap = XCreateColormap(dpy, RootWindow(dpy, vi->screen),
  80        vi->visual, AllocNone);
  81     swa.border_pixel = 0;
  82
  83     /* Create two windows */
  84     win1 = XCreateWindow(dpy, RootWindow(dpy, vi->screen),
  85        10, 10, 200, 200,
  86        0, vi->depth, InputOutput, vi->visual,
  87        CWBorderPixel | CWColormap, &swa);
  88     XStoreName(dpy, win1, "Test [L]");
  89     XMapWindow(dpy, win1);
  90     XMoveWindow(dpy, win1, 10, 10); /* Initial requested x,y may not be honored */
  91    {
  92       XSizeHints sizehints;
  93       static const char *name = "window";
  94       sizehints.x = 10;
  95       sizehints.y = 10;
  96       sizehints.width  = 200;
  97       sizehints.height = 200;
  98       sizehints.flags = USSize | USPosition;
  99       XSetNormalHints(dpy, win1, &sizehints);
 100       XSetStandardProperties(dpy, win1, name, name,
 101                               None, (char **)NULL, 0, &sizehints);
 102    }
 103
 104
 105     win2 = XCreateWindow(dpy, RootWindow(dpy, vi->screen),
 106        250, 10, 200, 200,
 107        0, vi->depth, InputOutput, vi->visual,
 108        CWBorderPixel | CWColormap, &swa);
 109     XStoreName(dpy, win1, "Test [R]");
 110     XMapWindow(dpy, win2);
 111     XMoveWindow(dpy, win2, 260, 10);
 112    {
 113       XSizeHints sizehints;
 114       static const char *name = "window";
 115       sizehints.x = 10;
 116       sizehints.y = 10;
 117       sizehints.width  = 200;
 118       sizehints.height = 200;
 119       sizehints.flags = USSize | USPosition;
 120       XSetNormalHints(dpy, win2, &sizehints);
 121       XSetStandardProperties(dpy, win2, name, name,
 122                               None, (char **)NULL, 0, &sizehints);
 123    }
 124
 125
 126     /* Now draw some spinning things */
 127     for (angle = 0; angle < 360*4; angle += 10.0) {
 128         /* Connect the context to window 1 */
 129         glXMakeCurrent(dpy, win1, ctx1);
 130
 131         /* Clear and draw in window 1 */
 132         glDrawBuffer(GL_BACK);
 133         glClearColor(1, 1, 0, 1);
 134         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 135         glColor3f(1, 0, 0);
 136         glBegin(GL_TRIANGLES);
 137         glVertex2f(0, 0);
 138         glVertex2f(cos(angle * DEGTOR), sin(angle * DEGTOR));
 139         glVertex2f(cos((angle + 20.0) * DEGTOR),
 140            sin((angle + 20.0) * DEGTOR));
 141         glEnd();
 142         glFlush();
 143
 144         if (test == 1 || test == 3 || test == 5)
 145             glXSwapBuffers(dpy, win1);
 146
 147         if (test == 5)
 148             glXCopyContext(dpy, ctx1, ctx2, GL_ALL_ATTRIB_BITS);
 149         /* Connect the context to window 2 */
 150         if (test == 3 || test == 4) {
 151             glXMakeCurrent(dpy, win2, ctx1);
 152         } else {
 153             glXMakeCurrent(dpy, win2, ctx2);
 154         }
 155
 156         /* Clear and draw in window 2 */
 157         glDrawBuffer(GL_BACK);
 158         glClearColor(0, 0, 1, 1);
 159         glClear(GL_COLOR_BUFFER_BIT);
 160         glColor3f(1, 1, 0);
 161         glBegin(GL_TRIANGLES);
 162         glVertex2f(0, 0);
 163         glVertex2f(cos(angle * DEGTOR), sin(angle * DEGTOR));
 164         glVertex2f(cos((angle + 20.0) * DEGTOR),
 165            sin((angle + 20.0) * DEGTOR));
 166         glEnd();
 167         glFlush();
 168
 169         /* Swap buffers */
 170         if (test == 2 || test == 4)
 171             glXSwapBuffers(dpy, win1);
 172         glXSwapBuffers(dpy, win2);
 173
 174         /* wait a while */
 175         glXWaitX();
 176         usleep(20000);
 177     }
 178
 179     return 0;
 180 }