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-rw-r--r--progs/demos/drawpix.c358
1 files changed, 358 insertions, 0 deletions
diff --git a/progs/demos/drawpix.c b/progs/demos/drawpix.c
new file mode 100644
index 000000000..d2f574867
--- /dev/null
+++ b/progs/demos/drawpix.c
@@ -0,0 +1,358 @@
+
+/*
+ * glDrawPixels demo/test/benchmark
+ *
+ * Brian Paul September 25, 1997 This file is in the public domain.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+#include <GL/glut.h>
+
+#include "readtex.h"
+
+#define IMAGE_FILE "../images/girl.rgb"
+
+static int ImgWidth, ImgHeight;
+static GLenum ImgFormat;
+static GLubyte *Image = NULL;
+
+static int Xpos, Ypos;
+static int SkipPixels, SkipRows;
+static int DrawWidth, DrawHeight;
+static int Scissor = 0;
+static int Fog = 0;
+static GLfloat Zpos = -1.0;
+static float Xzoom, Yzoom;
+static GLboolean DrawFront = GL_FALSE;
+static GLboolean Dither = GL_TRUE;
+
+
+static void Reset( void )
+{
+ Xpos = Ypos = 20;
+ DrawWidth = ImgWidth;
+ DrawHeight = ImgHeight;
+ SkipPixels = SkipRows = 0;
+ Scissor = 0;
+ Fog = 0;
+ Zpos = -1.0;
+ Xzoom = Yzoom = 1.0;
+}
+
+
+static void Display( void )
+{
+ glClear( GL_COLOR_BUFFER_BIT );
+
+#if 0
+ glRasterPos2i(Xpos, Ypos);
+#else
+ /* This allows negative raster positions: */
+ glRasterPos3f(0, 0, Zpos);
+ glBitmap(0, 0, 0, 0, Xpos, Ypos, NULL);
+#endif
+
+ glPixelStorei(GL_UNPACK_SKIP_PIXELS, SkipPixels);
+ glPixelStorei(GL_UNPACK_SKIP_ROWS, SkipRows);
+
+ glPixelZoom( Xzoom, Yzoom );
+
+ if (Scissor)
+ glEnable(GL_SCISSOR_TEST);
+
+ if (Fog)
+ glEnable(GL_FOG);
+
+ glDrawPixels(DrawWidth, DrawHeight, ImgFormat, GL_UNSIGNED_BYTE, Image);
+
+ glDisable(GL_SCISSOR_TEST);
+ glDisable(GL_FOG);
+
+ if (DrawFront)
+ glFinish();
+ else
+ glutSwapBuffers();
+}
+
+
+static void Benchmark( void )
+{
+ int startTime, endTime;
+ int draws = 500;
+ double seconds, pixelsPerSecond;
+
+ printf("Benchmarking...\n");
+ /* GL set-up */
+ glPixelStorei(GL_UNPACK_SKIP_PIXELS, SkipPixels);
+ glPixelStorei(GL_UNPACK_SKIP_ROWS, SkipRows);
+ glPixelZoom( Xzoom, Yzoom );
+ if (Scissor)
+ glEnable(GL_SCISSOR_TEST);
+ if (Fog)
+ glEnable(GL_FOG);
+
+ if (DrawFront)
+ glDrawBuffer(GL_FRONT);
+ else
+ glDrawBuffer(GL_BACK);
+
+ /* Run timing test */
+ draws = 0;
+ startTime = glutGet(GLUT_ELAPSED_TIME);
+ do {
+ glDrawPixels(DrawWidth, DrawHeight, ImgFormat, GL_UNSIGNED_BYTE, Image);
+ draws++;
+ endTime = glutGet(GLUT_ELAPSED_TIME);
+ } while (endTime - startTime < 4000); /* 4 seconds */
+
+ /* GL clean-up */
+ glDisable(GL_SCISSOR_TEST);
+ glDisable(GL_FOG);
+
+ /* Results */
+ seconds = (double) (endTime - startTime) / 1000.0;
+ pixelsPerSecond = draws * DrawWidth * DrawHeight / seconds;
+ printf("Result: %d draws in %f seconds = %f pixels/sec\n",
+ draws, seconds, pixelsPerSecond);
+}
+
+
+static void Reshape( int width, int height )
+{
+ glViewport( 0, 0, width, height );
+ glMatrixMode( GL_PROJECTION );
+ glLoadIdentity();
+ glOrtho( 0.0, width, 0.0, height, 0.0, 2.0 );
+ glMatrixMode( GL_MODELVIEW );
+ glLoadIdentity();
+
+ glScissor(width/4, height/4, width/2, height/2);
+}
+
+
+static void Key( unsigned char key, int x, int y )
+{
+ (void) x;
+ (void) y;
+ switch (key) {
+ case ' ':
+ Reset();
+ break;
+ case 'd':
+ Dither = !Dither;
+ if (Dither)
+ glEnable(GL_DITHER);
+ else
+ glDisable(GL_DITHER);
+ break;
+ case 'w':
+ if (DrawWidth > 0)
+ DrawWidth--;
+ break;
+ case 'W':
+ DrawWidth++;
+ break;
+ case 'h':
+ if (DrawHeight > 0)
+ DrawHeight--;
+ break;
+ case 'H':
+ DrawHeight++;
+ break;
+ case 'p':
+ if (SkipPixels > 0)
+ SkipPixels--;
+ break;
+ case 'P':
+ SkipPixels++;
+ break;
+ case 'r':
+ if (SkipRows > 0)
+ SkipRows--;
+ break;
+ case 'R':
+ SkipRows++;
+ break;
+ case 's':
+ Scissor = !Scissor;
+ break;
+ case 'x':
+ Xzoom -= 0.1;
+ break;
+ case 'X':
+ Xzoom += 0.1;
+ break;
+ case 'y':
+ Yzoom -= 0.1;
+ break;
+ case 'Y':
+ Yzoom += 0.1;
+ break;
+ case 'z':
+ Zpos -= 0.1;
+ printf("RasterPos Z = %g\n", Zpos);
+ break;
+ case 'Z':
+ Zpos += 0.1;
+ printf("RasterPos Z = %g\n", Zpos);
+ break;
+ case 'b':
+ Benchmark();
+ break;
+ case 'F':
+ Fog = !Fog;
+ printf("Fog %d\n", Fog);
+ break;
+ case 'f':
+ DrawFront = !DrawFront;
+ if (DrawFront)
+ glDrawBuffer(GL_FRONT);
+ else
+ glDrawBuffer(GL_BACK);
+ printf("glDrawBuffer(%s)\n", DrawFront ? "GL_FRONT" : "GL_BACK");
+ break;
+ case 27:
+ exit(0);
+ break;
+ }
+ glutPostRedisplay();
+}
+
+
+static void SpecialKey( int key, int x, int y )
+{
+ (void) x;
+ (void) y;
+ switch (key) {
+ case GLUT_KEY_UP:
+ Ypos += 1;
+ break;
+ case GLUT_KEY_DOWN:
+ Ypos -= 1;
+ break;
+ case GLUT_KEY_LEFT:
+ Xpos -= 1;
+ break;
+ case GLUT_KEY_RIGHT:
+ Xpos += 1;
+ break;
+ }
+ glutPostRedisplay();
+}
+
+
+static void Init( GLboolean ciMode, const char *filename )
+{
+ static const GLfloat fogColor[4] = {0, 1, 0, 0};
+
+ printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
+ printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
+
+ Image = LoadRGBImage( filename, &ImgWidth, &ImgHeight, &ImgFormat );
+ if (!Image) {
+ printf("Couldn't read %s\n", filename);
+ exit(0);
+ }
+
+ if (ciMode) {
+ /* Convert RGB image to grayscale */
+ GLubyte *indexImage = (GLubyte *) malloc( ImgWidth * ImgHeight );
+ GLint i;
+ for (i=0; i<ImgWidth*ImgHeight; i++) {
+ int gray = Image[i*3] + Image[i*3+1] + Image[i*3+2];
+ indexImage[i] = gray / 3;
+ }
+ free(Image);
+ Image = indexImage;
+ ImgFormat = GL_COLOR_INDEX;
+
+ for (i=0;i<255;i++) {
+ float g = i / 255.0;
+ glutSetColor(i, g, g, g);
+ }
+ }
+
+ printf("Loaded %d by %d image\n", ImgWidth, ImgHeight );
+
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ glPixelStorei(GL_UNPACK_ROW_LENGTH, ImgWidth);
+
+ glFogi(GL_FOG_MODE, GL_LINEAR);
+ glFogf(GL_FOG_START, 0);
+ glFogf(GL_FOG_END, 2);
+ glFogfv(GL_FOG_COLOR, fogColor);
+
+ Reset();
+}
+
+
+static void Usage(void)
+{
+ printf("Keys:\n");
+ printf(" SPACE Reset Parameters\n");
+ printf(" Up/Down Move image up/down\n");
+ printf(" Left/Right Move image left/right\n");
+ printf(" x Decrease X-axis PixelZoom\n");
+ printf(" X Increase X-axis PixelZoom\n");
+ printf(" y Decrease Y-axis PixelZoom\n");
+ printf(" Y Increase Y-axis PixelZoom\n");
+ printf(" w Decrease glDrawPixels width*\n");
+ printf(" W Increase glDrawPixels width*\n");
+ printf(" h Decrease glDrawPixels height*\n");
+ printf(" H Increase glDrawPixels height*\n");
+ printf(" p Decrease GL_UNPACK_SKIP_PIXELS*\n");
+ printf(" P Increase GL_UNPACK_SKIP_PIXELS*\n");
+ printf(" r Decrease GL_UNPACK_SKIP_ROWS*\n");
+ printf(" R Increase GL_UNPACK_SKIP_ROWS*\n");
+ printf(" s Toggle GL_SCISSOR_TEST\n");
+ printf(" F Toggle GL_FOG\n");
+ printf(" z Decrease RasterPos Z\n");
+ printf(" Z Increase RasterPos Z\n");
+
+ printf(" f Toggle front/back buffer drawing\n");
+ printf(" b Benchmark test\n");
+ printf(" ESC Exit\n");
+ printf("* Warning: no limits are imposed on these parameters so it's\n");
+ printf(" possible to cause a segfault if you go too far.\n");
+}
+
+
+int main( int argc, char *argv[] )
+{
+ GLboolean ciMode = GL_FALSE;
+ const char *filename = IMAGE_FILE;
+ int i = 1;
+
+ if (argc > i && strcmp(argv[i], "-ci")==0) {
+ ciMode = GL_TRUE;
+ i++;
+ }
+ if (argc > i) {
+ filename = argv[i];
+ }
+
+ glutInit( &argc, argv );
+ glutInitWindowPosition( 0, 0 );
+ glutInitWindowSize( 500, 400 );
+
+ if (ciMode)
+ glutInitDisplayMode( GLUT_INDEX | GLUT_DOUBLE );
+ else
+ glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE);
+
+ glutCreateWindow(argv[0]);
+
+ Init(ciMode, filename);
+ Usage();
+
+ glutReshapeFunc( Reshape );
+ glutKeyboardFunc( Key );
+ glutSpecialFunc( SpecialKey );
+ glutDisplayFunc( Display );
+
+ glutMainLoop();
+ return 0;
+}
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