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