Initial revision
diff --git a/progs/demos/clearspd.c b/progs/demos/clearspd.c
new file mode 100644
index 0000000..b2edf32
--- /dev/null
+++ b/progs/demos/clearspd.c
@@ -0,0 +1,221 @@
+/* $Id: clearspd.c,v 1.1 1999/08/19 00:55:40 jtg Exp $ */
+
+/*
+ * Simple GLUT program to measure glClear() and glutSwapBuffers() speed.
+ * Brian Paul February 15, 1997 This file in public domain.
+ */
+
+/*
+ * $Log: clearspd.c,v $
+ * Revision 1.1 1999/08/19 00:55:40 jtg
+ * Initial revision
+ *
+ * Revision 3.3 1999/03/28 18:18:33 brianp
+ * minor clean-up
+ *
+ * Revision 3.2 1999/03/18 08:16:34 joukj
+ *
+ * cmpstr needs string.h to included to avoid warnings
+ *
+ * Revision 3.1 1998/06/29 02:38:30 brianp
+ * removed unneeded includes
+ *
+ * Revision 3.0 1998/02/14 18:42:29 brianp
+ * initial rev
+ *
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+#include <GL/glut.h>
+
+
+static float MinPeriod = 2.0; /* 2 seconds */
+static int ColorMode = GLUT_RGB;
+static int Width = 400.0;
+static int Height = 400.0;
+static int Loops = 100;
+static float ClearColor = 0.0;
+static GLbitfield BufferMask = GL_COLOR_BUFFER_BIT;
+static GLboolean SwapFlag = GL_FALSE;
+
+
+
+static void Idle( void )
+{
+ glutPostRedisplay();
+}
+
+
+static void Display( void )
+{
+ double t0, t1;
+ double clearRate;
+ double pixelRate;
+ int i;
+
+ glClearColor( ClearColor, ClearColor, ClearColor, 0.0 );
+ ClearColor += 0.1;
+ if (ClearColor>1.0)
+ ClearColor = 0.0;
+
+ if (SwapFlag) {
+ t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
+ for (i=0;i<Loops;i++) {
+ glClear( BufferMask );
+ glutSwapBuffers();
+ }
+ t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
+ }
+ else {
+ t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
+ for (i=0;i<Loops;i++) {
+ glClear( BufferMask );
+ }
+ t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
+ glutSwapBuffers();
+ }
+
+ if (t1-t0 < MinPeriod) {
+ /* Next time do more clears to get longer elapsed time */
+ Loops *= 2;
+ return;
+ }
+
+ clearRate = Loops / (t1-t0);
+ pixelRate = clearRate * Width * Height;
+ if (SwapFlag) {
+ printf("Rate: %d clears+swaps in %gs = %g clears+swaps/s %d pixels/s\n",
+ Loops, t1-t0, clearRate, (int)pixelRate );
+ }
+ else {
+ printf("Rate: %d clears in %gs = %g clears/s %d pixels/s\n",
+ Loops, t1-t0, clearRate, (int)pixelRate);
+ }
+}
+
+
+static void Reshape( int width, int height )
+{
+ Width = width;
+ Height = height;
+ glViewport( 0, 0, width, height );
+ glMatrixMode( GL_PROJECTION );
+ glLoadIdentity();
+ glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
+ glMatrixMode( GL_MODELVIEW );
+ glLoadIdentity();
+}
+
+
+static void Key( unsigned char key, int x, int y )
+{
+ (void) x;
+ (void) y;
+ switch (key) {
+ case 27:
+ exit(0);
+ break;
+ }
+ glutPostRedisplay();
+}
+
+
+static void Init( int argc, char *argv[] )
+{
+ int i;
+ for (i=1; i<argc; i++) {
+ if (strcmp(argv[i],"+rgb")==0)
+ ColorMode = GLUT_RGB;
+ else if (strcmp(argv[i],"+ci")==0)
+ ColorMode = GLUT_INDEX;
+ else if (strcmp(argv[i],"-color")==0)
+ BufferMask = 0;
+ else if (strcmp(argv[i],"+depth")==0)
+ BufferMask |= GL_DEPTH_BUFFER_BIT;
+ else if (strcmp(argv[i],"+alpha")==0)
+ ColorMode = GLUT_RGB | GLUT_ALPHA;
+ else if (strcmp(argv[i],"+stencil")==0)
+ BufferMask |= GL_STENCIL_BUFFER_BIT;
+ else if (strcmp(argv[i],"+accum")==0)
+ BufferMask |= GL_ACCUM_BUFFER_BIT;
+ else if (strcmp(argv[i],"-width")==0) {
+ Width = atoi(argv[i+1]);
+ i++;
+ }
+ else if (strcmp(argv[i],"-height")==0) {
+ Height = atoi(argv[i+1]);
+ i++;
+ }
+ else if (strcmp(argv[i],"+swap")==0) {
+ SwapFlag = GL_TRUE;
+ }
+ else if (strcmp(argv[i],"-swap")==0) {
+ SwapFlag = GL_FALSE;
+ }
+ else
+ printf("Unknown option: %s\n", argv[i]);
+ }
+
+ if (ColorMode & GLUT_ALPHA)
+ printf("Mode: RGB + Alpha\n");
+ else if (ColorMode==GLUT_RGB)
+ printf("Mode: RGB\n");
+ else
+ printf("Mode: Color Index\n");
+ printf("SwapBuffers: %s\n", SwapFlag ? "yes" : "no" );
+ printf("Size: %d x %d\n", Width, Height);
+ printf("Buffers: ");
+ if (BufferMask & GL_COLOR_BUFFER_BIT) printf("color ");
+ if (BufferMask & GL_DEPTH_BUFFER_BIT) printf("depth ");
+ if (BufferMask & GL_STENCIL_BUFFER_BIT) printf("stencil ");
+ if (BufferMask & GL_ACCUM_BUFFER_BIT) printf("accum ");
+ printf("\n");
+}
+
+
+static void Help( const char *program )
+{
+ printf("%s options:\n", program);
+ printf(" +rgb RGB mode\n");
+ printf(" +ci color index mode\n");
+ printf(" -color don't clear color buffer\n");
+ printf(" +alpha clear alpha buffer\n");
+ printf(" +depth clear depth buffer\n");
+ printf(" +stencil clear stencil buffer\n");
+ printf(" +accum clear accum buffer\n");
+ printf(" +swap also do SwapBuffers\n");
+ printf(" -swap don't do SwapBuffers\n");
+}
+
+
+int main( int argc, char *argv[] )
+{
+ printf("For options: %s -help\n", argv[0]);
+
+ Init( argc, argv );
+
+ glutInit( &argc, argv );
+ glutInitWindowSize( (int) Width, (int) Height );
+ glutInitWindowPosition( 0, 0 );
+
+ glutInitDisplayMode( ColorMode | GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL | GLUT_ACCUM );
+
+ glutCreateWindow( argv[0] );
+
+ if (argc==2 && strcmp(argv[1],"-help")==0) {
+ Help(argv[0]);
+ return 0;
+ }
+
+ glutReshapeFunc( Reshape );
+ glutKeyboardFunc( Key );
+ glutDisplayFunc( Display );
+ glutIdleFunc( Idle );
+
+ glutMainLoop();
+ return 0;
+}