progs/demos/streaming_rect.c

   1 /*
   2  * GL_ARB_pixel_buffer_object test
   3  *
   4  * Command line options:
   5  *    -w WIDTH -h HEIGHT   sets window size
   6  *
   7  */
   8
   9 #include <math.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <GL/glew.h>
  14 #include <GL/glut.h>
  15
  16 #include "readtex.h"
  17
  18
  19 #define ANIMATE 10
  20 #define PBO 11
  21 #define QUIT 100
  22
  23 static GLuint DrawPBO;
  24
  25 static GLboolean Animate = GL_TRUE;
  26 static GLboolean use_pbo = 1;
  27 static GLboolean whole_rect = 1;
  28
  29 static GLfloat Drift = 0.0;
  30 static GLfloat drift_increment = 1/255.0;
  31 static GLfloat Xrot = 20.0, Yrot = 30.0;
  32
  33 static GLuint Width = 1024;
  34 static GLuint Height = 512;
  35
  36
  37 static void Idle( void )
  38 {
  39    if (Animate) {
  40
  41       Drift += drift_increment;
  42       if (Drift >= 1.0)
  43          Drift = 0.0;
  44
  45       glutPostRedisplay();
  46    }
  47 }
  48
  49 /*static int max( int a, int b ) { return a > b ? a : b; }*/
  50
  51 #ifndef min
  52 static int min( int a, int b ) { return a < b ? a : b; }
  53 #endif
  54
  55 static void DrawObject()
  56 {
  57    GLint size = Width * Height * 4;
  58
  59    if (use_pbo) {
  60       /* XXX: This is extremely important - semantically makes the buffer
  61        * contents undefined, but in practice means that the driver can
  62        * release the old copy of the texture and allocate a new one
  63        * without waiting for outstanding rendering to complete.
  64        */
  65       glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_EXT, DrawPBO);
  66       glBufferDataARB(GL_PIXEL_UNPACK_BUFFER_EXT, size, NULL, GL_STREAM_DRAW_ARB);
  67
  68       {
  69          char *image = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_EXT, GL_WRITE_ONLY_ARB);
  70
  71          printf("char %d\n", (unsigned char)(Drift * 255));
  72
  73          memset(image, (unsigned char)(Drift * 255), size);
  74
  75          glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_EXT);
  76       }
  77
  78
  79       /* BGRA is required for most hardware paths:
  80        */
  81       glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA, Width, Height, 0,
  82                    GL_BGRA, GL_UNSIGNED_BYTE, NULL);
  83    }
  84    else {
  85       static char *image = NULL;
  86
  87       if (image == NULL)
  88          image = malloc(size);
  89
  90       glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_EXT, 0);
  91
  92       memset(image, (unsigned char)(Drift * 255), size);
  93
  94       /* BGRA should be the fast path for regular uploads as well.
  95        */
  96       glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA, Width, Height, 0,
  97                    GL_BGRA, GL_UNSIGNED_BYTE, image);
  98    }
  99
 100    {
 101       int x,y,w,h;
 102
 103       if (whole_rect) {
 104          x = y = 0;
 105          w = Width;
 106          h = Height;
 107       }
 108       else {
 109          x = y = 0;
 110          w = min(10, Width);
 111          h = min(10, Height);
 112       }
 113
 114       glBegin(GL_QUADS);
 115
 116       glTexCoord2f( x, y);
 117       glVertex2f( x, y );
 118
 119       glTexCoord2f( x, y + h);
 120       glVertex2f( x, y + h);
 121
 122       glTexCoord2f( x + w + .5, y + h);
 123       glVertex2f( x + w, y + h );
 124
 125       glTexCoord2f( x + w, y + .5);
 126       glVertex2f( x + w, y );
 127
 128       glEnd();
 129    }
 130 }
 131
 132
 133
 134 static void Display( void )
 135 {
 136    static GLint T0 = 0;
 137    static GLint Frames = 0;
 138    GLint t;
 139
 140    glClear( GL_COLOR_BUFFER_BIT );
 141
 142    glPushMatrix();
 143       DrawObject();
 144    glPopMatrix();
 145
 146    glutSwapBuffers();
 147
 148    Frames++;
 149
 150    t = glutGet(GLUT_ELAPSED_TIME);
 151    if (t - T0 >= 1000) {
 152       GLfloat seconds = (t - T0) / 1000.0;
 153
 154       GLfloat fps = Frames / seconds;
 155       printf("%d frames in %6.3f seconds = %6.3f FPS\n", Frames, seconds, fps);
 156       fflush(stdout);
 157
 158       drift_increment = 2.2 * seconds / Frames;
 159       T0 = t;
 160       Frames = 0;
 161    }
 162 }
 163
 164
 165 static void Reshape( int width, int height )
 166 {
 167    glViewport( 0, 0, width, height );
 168    glMatrixMode( GL_PROJECTION );
 169    glLoadIdentity();
 170 /*    glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 100.0 ); */
 171    gluOrtho2D( 0, width, height, 0 );
 172    glMatrixMode( GL_MODELVIEW );
 173    glLoadIdentity();
 174    glTranslatef(0.375, 0.375, 0);
 175 }
 176
 177
 178 static void ModeMenu(int entry)
 179 {
 180    if (entry==ANIMATE) {
 181       Animate = !Animate;
 182    }
 183    else if (entry==PBO) {
 184       use_pbo = !use_pbo;
 185    }
 186    else if (entry==QUIT) {
 187       exit(0);
 188    }
 189
 190    glutPostRedisplay();
 191 }
 192
 193
 194 static void Key( unsigned char key, int x, int y )
 195 {
 196    (void) x;
 197    (void) y;
 198    switch (key) {
 199       case 27:
 200          exit(0);
 201          break;
 202    }
 203    glutPostRedisplay();
 204 }
 205
 206
 207 static void SpecialKey( int key, int x, int y )
 208 {
 209    float step = 3.0;
 210    (void) x;
 211    (void) y;
 212
 213    switch (key) {
 214       case GLUT_KEY_UP:
 215          Xrot += step;
 216          break;
 217       case GLUT_KEY_DOWN:
 218          Xrot -= step;
 219          break;
 220       case GLUT_KEY_LEFT:
 221          Yrot += step;
 222          break;
 223       case GLUT_KEY_RIGHT:
 224          Yrot -= step;
 225          break;
 226    }
 227    glutPostRedisplay();
 228 }
 229
 230
 231 static void Init( int argc, char *argv[] )
 232 {
 233    const char *exten = (const char *) glGetString(GL_EXTENSIONS);
 234    GLuint texObj;
 235    GLint size;
 236
 237
 238    if (!strstr(exten, "GL_ARB_pixel_buffer_object")) {
 239       printf("Sorry, GL_ARB_pixel_buffer_object not supported by this renderer.\n");
 240       exit(1);
 241    }
 242
 243    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &size);
 244    printf("%d x %d max texture size\n", size, size);
 245
 246    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 247
 248    /* allocate two texture objects */
 249    glGenTextures(1, &texObj);
 250
 251    /* setup the texture objects */
 252    glActiveTextureARB(GL_TEXTURE0_ARB);
 253    glBindTexture(GL_TEXTURE_RECTANGLE_ARB, texObj);
 254
 255    glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 256    glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 257
 258    glGenBuffersARB(1, &DrawPBO);
 259
 260    glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_EXT, DrawPBO);
 261    glBufferDataARB(GL_PIXEL_UNPACK_BUFFER_EXT,
 262                    Width * Height * 4, NULL, GL_STREAM_DRAW);
 263
 264    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
 265
 266    glEnable(GL_TEXTURE_RECTANGLE_ARB);
 267
 268    glShadeModel(GL_SMOOTH);
 269    glClearColor(0.3, 0.3, 0.4, 1.0);
 270
 271    if (argc > 1 && strcmp(argv[1], "-info")==0) {
 272       printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
 273       printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
 274       printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
 275       printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
 276    }
 277 }
 278
 279
 280 int main( int argc, char *argv[] )
 281 {
 282    GLint i;
 283
 284    glutInit( &argc, argv );
 285
 286    for (i = 1; i < argc; i++) {
 287       if (strcmp(argv[i], "-w") == 0) {
 288          Width = atoi(argv[i+1]);
 289          if (Width <= 0) {
 290             printf("Error, bad width\n");
 291             exit(1);
 292          }
 293          i++;
 294       }
 295       else if (strcmp(argv[i], "-h") == 0) {
 296          Height = atoi(argv[i+1]);
 297          if (Height <= 0) {
 298             printf("Error, bad height\n");
 299             exit(1);
 300          }
 301          i++;
 302       }
 303    }
 304
 305    glutInitWindowSize( Width, Height );
 306    glutInitWindowPosition( 0, 0 );
 307    glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
 308    glutCreateWindow(argv[0] );
 309    glewInit();
 310
 311    Init( argc, argv );
 312
 313    glutReshapeFunc( Reshape );
 314    glutKeyboardFunc( Key );
 315    glutSpecialFunc( SpecialKey );
 316    glutDisplayFunc( Display );
 317    glutIdleFunc( Idle );
 318
 319    glutCreateMenu(ModeMenu);
 320    glutAddMenuEntry("Toggle Animation", ANIMATE);
 321    glutAddMenuEntry("Toggle PBO", PBO);
 322    glutAddMenuEntry("Quit", QUIT);
 323    glutAttachMenu(GLUT_RIGHT_BUTTON);
 324
 325    glutMainLoop();
 326    return 0;
 327 }