progs/xdemos/sharedtex.c

   1 /*
   2  * Test sharing of texture objects by two rendering contexts.
   3  * In particular, test that changing a texture object in one context
   4  * effects the texture in the second context.
   5  *
   6  * Brian Paul
   7  * 30 Apr 2008
   8  *
   9  * Copyright (C) 2008  Brian Paul   All Rights Reserved.
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a
  12  * copy of this software and associated documentation files (the "Software"),
  13  * to deal in the Software without restriction, including without limitation
  14  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  15  * and/or sell copies of the Software, and to permit persons to whom the
  16  * Software is furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included
  19  * in all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  22  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  24  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  25  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  26  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27  */
  28
  29
  30 #include <GL/gl.h>
  31 #include <GL/glx.h>
  32 #include <assert.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <unistd.h>
  37 #include <X11/keysym.h>
  38
  39
  40 #define MAX_CONTEXTS 2
  41
  42 #define TEX_SIZE 32
  43
  44 static const char *DisplayName = NULL;
  45 static Display *Dpy;
  46 static XVisualInfo *VisInfo;
  47 static Window Win;
  48 static GLXContext Contexts[MAX_CONTEXTS];
  49 static int WinWidth = 300, WinHeight = 300;
  50
  51 static int DrawContext = 0, TexContext = 1;
  52
  53 static GLuint TexObj = 0;
  54 static GLboolean NewTexture = GL_FALSE;
  55
  56
  57 static void
  58 Error(const char *msg)
  59 {
  60    fprintf(stderr, "sharedtex error: %s\n", msg);
  61    exit(1);
  62 }
  63
  64
  65 static void
  66 CreateWindow(const char *name)
  67 {
  68    int attrib[] = { GLX_RGBA,
  69                     GLX_RED_SIZE, 1,
  70                     GLX_GREEN_SIZE, 1,
  71                     GLX_BLUE_SIZE, 1,
  72                     GLX_DOUBLEBUFFER,
  73                     None };
  74    int scrnum;
  75    XSetWindowAttributes attr;
  76    unsigned long mask;
  77    Window root;
  78    int xpos = 0, ypos = 0;
  79    static int n = 0;
  80
  81    scrnum = DefaultScreen(Dpy);
  82    root = RootWindow(Dpy, scrnum);
  83
  84    VisInfo = glXChooseVisual(Dpy, scrnum, attrib);
  85    if (!VisInfo) {
  86       Error("Unable to find RGB, double-buffered visual");
  87    }
  88
  89    /* window attributes */
  90    xpos = (n % 10) * 100;
  91    ypos = (n / 10) * 100;
  92    n++;
  93
  94    attr.background_pixel = 0;
  95    attr.border_pixel = 0;
  96    attr.colormap = XCreateColormap(Dpy, root, VisInfo->visual, AllocNone);
  97    attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
  98    mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
  99
 100    Win = XCreateWindow(Dpy, root, xpos, ypos, WinWidth, WinHeight,
 101                         0, VisInfo->depth, InputOutput,
 102                         VisInfo->visual, mask, &attr);
 103    if (!Win) {
 104       Error("Couldn't create window");
 105    }
 106
 107    {
 108       XSizeHints sizehints;
 109       sizehints.x = xpos;
 110       sizehints.y = ypos;
 111       sizehints.width  = WinWidth;
 112       sizehints.height = WinHeight;
 113       sizehints.flags = USSize | USPosition;
 114       XSetNormalHints(Dpy, Win, &sizehints);
 115       XSetStandardProperties(Dpy, Win, name, name,
 116                               None, (char **)NULL, 0, &sizehints);
 117    }
 118
 119    XMapWindow(Dpy, Win);
 120 }
 121
 122
 123 /**
 124  * Change texture image, using TexContext
 125  */
 126 static void
 127 ModifyTexture(void)
 128 {
 129    GLuint tex[TEX_SIZE][TEX_SIZE];
 130    GLuint c0, c1;
 131    int i, j;
 132
 133    if (Win && !glXMakeCurrent(Dpy, Win, Contexts[TexContext])) {
 134       Error("glXMakeCurrent failed");
 135    }
 136
 137    /* choose two random colors */
 138    c0 = rand() & 0xffffffff;
 139    c1 = rand() & 0xffffffff;
 140
 141    for (i = 0; i < TEX_SIZE; i++) {
 142       for (j = 0; j < TEX_SIZE; j++) {
 143          if (((i / 4) ^ (j / 4)) & 1) {
 144             tex[i][j] = c0;
 145          }
 146          else {
 147             tex[i][j] = c1;
 148          }
 149       }
 150    }
 151
 152    glBindTexture(GL_TEXTURE_2D, TexObj);
 153    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, TEX_SIZE, TEX_SIZE, 0,
 154                 GL_RGBA, GL_UNSIGNED_BYTE, tex);
 155
 156    NewTexture = GL_TRUE;
 157 }
 158
 159
 160 static void
 161 InitContext(void)
 162 {
 163    glGenTextures(1, &TexObj);
 164    assert(TexObj);
 165    glBindTexture(GL_TEXTURE_2D, TexObj);
 166    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 167    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 168    glEnable(GL_TEXTURE_2D);
 169
 170    printf("GL_RENDERER = %s\n", (char*) glGetString(GL_RENDERER));
 171 }
 172
 173
 174 static void
 175 Setup(void)
 176 {
 177    int i;
 178
 179    Dpy = XOpenDisplay(DisplayName);
 180    if (!Dpy) {
 181       Error("Unable to open display");
 182    }
 183
 184    CreateWindow("sharedtex");
 185
 186    for (i = 0; i < MAX_CONTEXTS; i++) {
 187       GLXContext share = i > 0 ? Contexts[0] : 0;
 188
 189       Contexts[i] = glXCreateContext(Dpy, VisInfo, share, True);
 190       if (!Contexts[i]) {
 191          Error("Unable to create GLX context");
 192       }
 193
 194       if (!glXMakeCurrent(Dpy, Win, Contexts[i])) {
 195          Error("glXMakeCurrent failed");
 196       }
 197
 198       InitContext();
 199    }
 200
 201    ModifyTexture();
 202 }
 203
 204
 205 /**
 206  * Redraw window, using DrawContext
 207  */
 208 static void
 209 Redraw(void)
 210 {
 211    static float rot = 0.0;
 212    float ar;
 213
 214    rot += 1.0;
 215
 216    if (Win && !glXMakeCurrent(Dpy, Win, Contexts[DrawContext])) {
 217       Error("glXMakeCurrent failed");
 218    }
 219
 220    glViewport(0, 0, WinWidth, WinHeight);
 221    ar = (float) WinWidth / (float) WinHeight;
 222    glMatrixMode(GL_PROJECTION);
 223    glLoadIdentity();
 224    glOrtho(-ar, ar, -1.0, 1.0, -1.0, 1.0);
 225    glMatrixMode(GL_MODELVIEW);
 226
 227    glShadeModel(GL_FLAT);
 228    glClearColor(0.5, 0.5, 0.5, 1.0);
 229    glClear(GL_COLOR_BUFFER_BIT);
 230
 231    glPushMatrix();
 232    glRotatef(rot, 0, 0, 1);
 233    glScalef(0.7, 0.7, 0.7);
 234
 235    if (NewTexture) {
 236       /* rebind to get new contents */
 237       glBindTexture(GL_TEXTURE_2D, TexObj);
 238       NewTexture = GL_FALSE;
 239    }
 240
 241    /* draw textured quad */
 242    glBegin(GL_POLYGON);
 243    glTexCoord2f( 0.0, 0.0 );   glVertex2f( -1.0, -1.0 );
 244    glTexCoord2f( 1.0, 0.0 );   glVertex2f(  1.0, -1.0 );
 245    glTexCoord2f( 1.0, 1.0 );   glVertex2f(  1.0,  1.0 );
 246    glTexCoord2f( 0.0, 1.0 );   glVertex2f( -1.0,  1.0 );
 247    glEnd();
 248
 249    glPopMatrix();
 250
 251    if (Win)
 252       glXSwapBuffers(Dpy, Win);
 253 }
 254
 255
 256 static void
 257 EventLoop(void)
 258 {
 259    while (1) {
 260       while (XPending(Dpy) > 0) {
 261          XEvent event;
 262          XNextEvent(Dpy, &event);
 263
 264          switch (event.type) {
 265          case Expose:
 266             Redraw();
 267             break;
 268          case ConfigureNotify:
 269             WinWidth = event.xconfigure.width;
 270             WinHeight = event.xconfigure.height;
 271             break;
 272          case KeyPress:
 273             {
 274                char buf[100];
 275                KeySym keySym;
 276                XComposeStatus stat;
 277                XLookupString(&event.xkey, buf, sizeof(buf), &keySym, &stat);
 278                switch (keySym) {
 279                case XK_Escape:
 280                   exit(0);
 281                   break;
 282                case XK_t:
 283                case XK_T:
 284                   ModifyTexture();
 285                   break;
 286                default:
 287                   ;
 288                }
 289             }
 290             Redraw();
 291             break;
 292          default:
 293             /*no-op*/ ;
 294          }
 295       }
 296
 297       Redraw();
 298       usleep(10000);
 299    }
 300 }
 301
 302
 303
 304
 305 int
 306 main(int argc, char *argv[])
 307 {
 308    int i;
 309
 310    for (i = 1; i < argc; i++) {
 311       if (strcmp(argv[i], "-display") == 0 && i < argc) {
 312          DisplayName = argv[i+1];
 313          i++;
 314       }
 315    }
 316
 317    Setup();
 318
 319    printf("Press 't' to change texture image/colors\n");
 320
 321    EventLoop();
 322
 323    return 0;
 324 }