-/* $Id: drawpix.c,v 1.2 1999/10/21 22:13:58 brianp Exp $ */
/*
* glDrawPixels demo/test/benchmark
* Brian Paul September 25, 1997 This file is in the public domain.
*/
-/*
- * $Log: drawpix.c,v $
- * Revision 1.2 1999/10/21 22:13:58 brianp
- * added f key to toggle front/back drawing
- *
- * Revision 1.1.1.1 1999/08/19 00:55:40 jtg
- * Imported sources
- *
- * Revision 3.3 1999/03/28 18:18:33 brianp
- * minor clean-up
- *
- * Revision 3.2 1998/11/05 04:34:04 brianp
- * moved image files to ../images/ directory
- *
- * Revision 3.1 1998/02/22 16:43:17 brianp
- * added a few casts to silence compiler warnings
- *
- * 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>
-#include "../util/readtex.c" /* a hack, I know */
+#include "readtex.h"
#define IMAGE_FILE "../images/girl.rgb"
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 int win = 0;
static void Reset( void )
DrawHeight = ImgHeight;
SkipPixels = SkipRows = 0;
Scissor = 0;
+ Fog = 0;
+ Zpos = -1.0;
Xzoom = Yzoom = 1.0;
}
glRasterPos2i(Xpos, Ypos);
#else
/* This allows negative raster positions: */
- glRasterPos2i(0, 0);
+ glRasterPos3f(0, 0, Zpos);
glBitmap(0, 0, 0, 0, Xpos, Ypos, NULL);
#endif
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)
+ if (DrawFront)
+ glFinish();
+ else
glutSwapBuffers();
}
glPixelZoom( Xzoom, Yzoom );
if (Scissor)
glEnable(GL_SCISSOR_TEST);
+ if (Fog)
+ glEnable(GL_FOG);
if (DrawFront)
glDrawBuffer(GL_FRONT);
/* GL clean-up */
glDisable(GL_SCISSOR_TEST);
+ glDisable(GL_FOG);
/* Results */
seconds = (double) (endTime - startTime) / 1000.0;
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
- glOrtho( 0.0, width, 0.0, height, -1.0, 1.0 );
+ glOrtho( 0.0, width, 0.0, height, 0.0, 2.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
case ' ':
Reset();
break;
+ case 'd':
+ Dither = !Dither;
+ if (Dither)
+ glEnable(GL_DITHER);
+ else
+ glDisable(GL_DITHER);
+ break;
case 'w':
if (DrawWidth > 0)
DrawWidth--;
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)
printf("glDrawBuffer(%s)\n", DrawFront ? "GL_FRONT" : "GL_BACK");
break;
case 27:
+ glutDestroyWindow(win);
exit(0);
break;
}
}
-static void Init( GLboolean ciMode )
+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( IMAGE_FILE, &ImgWidth, &ImgHeight, &ImgFormat );
+ Image = LoadRGBImage( filename, &ImgWidth, &ImgHeight, &ImgFormat );
if (!Image) {
- printf("Couldn't read %s\n", IMAGE_FILE);
+ printf("Couldn't read %s\n", filename);
exit(0);
}
if (ciMode) {
/* Convert RGB image to grayscale */
- GLubyte *indexImage = malloc( ImgWidth * ImgHeight );
+ 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];
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\n");
+ printf(" SPACE Reset Parameters\n");
printf(" Up/Down Move image up/down\n");
printf(" Left/Right Move image left/right\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(" 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 > 1 && strcmp(argv[1], "-ci")==0) {
+ glutInitWindowSize( 500, 400 );
+ glutInit( &argc, argv );
+
+ 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 );
+ glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE);
- glutCreateWindow(argv[0]);
+ win = glutCreateWindow(argv[0]);
- Init(ciMode);
+ Init(ciMode, filename);
Usage();
glutReshapeFunc( Reshape );