src/tests/readrate.c

   1 /*
   2  * Test glReadPixels speed
   3  * Brian Paul
   4  * 9 April 2004
   5  *
   6  * Compile:
   7  * gcc readrate.c -L/usr/X11R6/lib -lglut -lGLU -lGL -lX11 -o readrate
   8  */
   9
  10 #define GL_GLEXT_PROTOTYPES
  11 #include <assert.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <math.h>
  15 #include <GL/glut.h>
  16
  17 /* Hack, to test drawing instead of reading */
  18 #define DRAW 0
  19
  20 #define MAX_WIDTH 1280
  21 #define MAX_HEIGHT 1024
  22
  23 #define NUM_WIDTHS 4
  24 #define NUM_HEIGHTS 4
  25 static const GLint Widths[] = {256, 512, 1024, 1280};
  26 static const GLint Heights[] = {4, 32, 256, 512, 768, 1024};
  27 static int WidthIndex = 1, HeightIndex = 3;
  28 static GLubyte *Buffer = NULL;
  29 static GLboolean Benchmark = GL_TRUE;
  30
  31 #define NUM_PBO 2
  32
  33 static GLuint PBObjects[4];
  34
  35 static GLboolean HavePBO = GL_FALSE;
  36
  37
  38 struct format_type {
  39    const char *Name;
  40    GLuint Bytes;
  41    GLenum Format;
  42    GLenum Type;
  43 };
  44
  45 static struct format_type Formats[] = {
  46    { "GL_RGB, GLubyte", 3, GL_RGB, GL_UNSIGNED_BYTE },
  47    { "GL_BGR, GLubyte", 3, GL_BGR, GL_UNSIGNED_BYTE },
  48    { "GL_RGBA, GLubyte", 4, GL_RGBA, GL_UNSIGNED_BYTE },
  49    { "GL_BGRA, GLubyte", 4, GL_BGRA, GL_UNSIGNED_BYTE },
  50    { "GL_ABGR, GLubyte", 4, GL_ABGR_EXT, GL_UNSIGNED_BYTE },
  51    { "GL_RGBA, GLuint_8_8_8_8", 4, GL_RGBA, GL_UNSIGNED_INT_8_8_8_8 },
  52    { "GL_BGRA, GLuint_8_8_8_8", 4, GL_BGRA_EXT, GL_UNSIGNED_INT_8_8_8_8 },
  53    { "GL_BGRA, GLuint_8_8_8_8_rev", 4, GL_BGRA_EXT, GL_UNSIGNED_INT_8_8_8_8_REV },
  54 #ifdef GL_EXT_packed_depth_stencil
  55    { "GL_DEPTH_STENCIL_EXT, GLuint24+8", 4, GL_DEPTH_STENCIL_EXT, GL_UNSIGNED_INT_24_8_EXT },
  56 #endif
  57    { "GL_DEPTH_COMPONENT, GLfloat", 4, GL_DEPTH_COMPONENT, GL_FLOAT },
  58    { "GL_DEPTH_COMPONENT, GLuint", 4, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT }
  59 };
  60
  61 #define NUM_FORMATS (sizeof(Formats) / sizeof(struct format_type))
  62
  63
  64 static void
  65 PrintString(const char *s)
  66 {
  67    while (*s) {
  68       glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s);
  69       s++;
  70    }
  71 }
  72
  73
  74 static void
  75 MeasureFormat(struct format_type *fmt, GLint width, GLint height, GLuint pbo)
  76 {
  77    double t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
  78    double t1;
  79    int j;
  80
  81    for (j = 0; ; j++) {
  82
  83       glBegin(GL_POINTS);
  84       glVertex2f(1,1);
  85       glEnd();
  86
  87 #if DRAW
  88       glWindowPos2iARB(0,0);
  89       glDrawPixels(width, height,
  90                    fmt->Format, fmt->Type, Buffer);
  91       glFinish();
  92 #else
  93       if (pbo) {
  94          glBindBufferARB(GL_PIXEL_PACK_BUFFER_EXT, PBObjects[j % NUM_PBO]);
  95          glReadPixels(0, 0, width, height,
  96                       fmt->Format, fmt->Type, 0);
  97       }
  98       else {
  99          glReadPixels(0, 0, width, height,
 100                       fmt->Format, fmt->Type, Buffer);
 101       }
 102 #endif
 103
 104       t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
 105       if (t1 - t0 > 2.0) {
 106          GLdouble rate = width * height / (1024.0 * 1024.0) * j / (t1 - t0);
 107 #if DRAW
 108          printf("%-32s  %.2f draws/sec %.2f MPixels/sec  %.2f MBytes/sec\n",
 109                 fmt->Name, j / (t1-t0), rate, rate * fmt->Bytes);
 110 #else
 111          printf("%-32s  %.2f reads/sec %.2f MPixels/sec  %.2f MBytes/sec\n",
 112                 fmt->Name, j / (t1-t0), rate, rate * fmt->Bytes);
 113 #endif
 114          break;
 115       }
 116
 117       if (j == 0) {
 118          /* check for error */
 119          GLenum err = glGetError();
 120          if (err) {
 121             printf("GL Error 0x%x for %s\n", err, fmt->Name);
 122             return;
 123          }
 124       }
 125    }
 126 }
 127
 128
 129
 130 static void
 131 Draw(void)
 132 {
 133    char str[1000];
 134    int width = Widths[WidthIndex];
 135    int height = Heights[HeightIndex];
 136    int y = MAX_HEIGHT - 50;
 137
 138    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 139
 140    glWindowPos2iARB(10, y);
 141    sprintf(str, "ReadPixels size: %d x %d", width, height);
 142    PrintString(str);
 143    y -= 14;
 144
 145    glWindowPos2iARB(10, y);
 146    PrintString("Press up/down/left/right to change image size.");
 147    y -= 14;
 148
 149    glWindowPos2iARB(10, y);
 150    PrintString("Press 'b' to run benchmark test.");
 151    y -= 14;
 152
 153    if (Benchmark) {
 154       glWindowPos2iARB(10, y);
 155       PrintString("Testing...");
 156    }
 157
 158    glutSwapBuffers();
 159
 160    if (Benchmark) {
 161       GLuint i, pbo;
 162 #if DRAW
 163       printf("Draw size: Width=%d Height=%d\n", width, height);
 164 #else
 165       printf("Read size: Width=%d Height=%d\n", width, height);
 166 #endif
 167       for (pbo = 0; pbo <= HavePBO; pbo++) {
 168          printf("Pixel Buffer Object: %d\n", pbo);
 169
 170          if (pbo == 0) {
 171             glBindBufferARB(GL_PIXEL_PACK_BUFFER_EXT, 0);
 172          }
 173
 174          for (i = 0; i < NUM_FORMATS; i++) {
 175             MeasureFormat(Formats + i, width, height, pbo);
 176          }
 177       }
 178
 179       Benchmark = GL_FALSE;
 180
 181       /* redraw window text */
 182       glutPostRedisplay();
 183    }
 184
 185 }
 186
 187
 188 static void
 189 Reshape(int width, int height)
 190 {
 191    glViewport(0, 0, width, height);
 192    glMatrixMode(GL_PROJECTION);
 193    glLoadIdentity();
 194    glOrtho(-1, 1, -1, 1, -1, 1);
 195    glMatrixMode(GL_MODELVIEW);
 196    glLoadIdentity();
 197 }
 198
 199
 200 static void
 201 Key(unsigned char key, int x, int y)
 202 {
 203    (void) x;
 204    (void) y;
 205    switch (key) {
 206       case 'b':
 207          Benchmark = 1;
 208          break;
 209       case 27:
 210          exit(0);
 211          break;
 212    }
 213    glutPostRedisplay();
 214 }
 215
 216
 217 static void
 218 SpecialKey(int key, int x, int y)
 219 {
 220    (void) x;
 221    (void) y;
 222    switch (key) {
 223       case GLUT_KEY_UP:
 224          if (HeightIndex + 1 < NUM_WIDTHS)
 225             HeightIndex++;
 226          break;
 227       case GLUT_KEY_DOWN:
 228          if (HeightIndex > 0)
 229             HeightIndex--;
 230          break;
 231       case GLUT_KEY_LEFT:
 232          if (WidthIndex > 0)
 233             WidthIndex--;
 234          break;
 235       case GLUT_KEY_RIGHT:
 236          if (WidthIndex + 1 < NUM_HEIGHTS)
 237             WidthIndex++;
 238          break;
 239    }
 240    glutPostRedisplay();
 241 }
 242
 243
 244 static void
 245 Init(void)
 246 {
 247    Buffer = malloc(MAX_WIDTH * MAX_HEIGHT * 4);
 248    assert(Buffer);
 249 #if DRAW
 250    printf("glDrawPixels test report:\n");
 251 #else
 252    printf("glReadPixels test report:\n");
 253 #endif
 254    printf("GL_RENDERER: %s\n", (char *) glGetString(GL_RENDERER));
 255    printf("GL_VERSION: %s\n", (char *) glGetString(GL_VERSION));
 256
 257    if (glutExtensionSupported("GL_ARB_pixel_buffer_object")) {
 258       int i;
 259       HavePBO = 1;
 260       glGenBuffersARB(NUM_PBO, PBObjects);
 261       for (i = 0; i < NUM_PBO; i++) {
 262          glBindBufferARB(GL_PIXEL_PACK_BUFFER_EXT, PBObjects[i]);
 263          glBufferDataARB(GL_PIXEL_PACK_BUFFER_EXT,
 264                          MAX_WIDTH * MAX_HEIGHT * 4, NULL, GL_STREAM_READ);
 265       }
 266    }
 267 }
 268
 269
 270 int
 271 main(int argc, char *argv[])
 272 {
 273    glutInit(&argc, argv);
 274    glutInitWindowPosition(0, 0);
 275    glutInitWindowSize(MAX_WIDTH, MAX_HEIGHT);
 276    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL);
 277    glutCreateWindow(argv[0]);
 278    glutReshapeFunc(Reshape);
 279    glutKeyboardFunc(Key);
 280    glutSpecialFunc(SpecialKey);
 281    glutDisplayFunc(Draw);
 282    Init();
 283    glutMainLoop();
 284    return 0;
 285 }