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/* GL_ARB_fragment_program texture test */
#include <assert.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#define GL_GLEXT_PROTOTYPES
#include <GL/glut.h>
#include "readtex.c"
#define TEXTURE_FILE "../images/girl.rgb"
static GLfloat Xrot = 0.0, Yrot = 0.0, Zrot = 0.0;
static void Display( void )
{
glClear( GL_COLOR_BUFFER_BIT );
glPushMatrix();
glRotatef(Xrot, 1.0, 0.0, 0.0);
glRotatef(Yrot, 0.0, 1.0, 0.0);
glRotatef(Zrot, 0.0, 0.0, 1.0);
glBegin(GL_POLYGON);
#define Q 2
glColor4f(1.0, 1.0, 1.0, 1); glTexCoord4f(0, 0, 0, Q); glVertex2f(-1, -1);
glColor4f(0.2, 0.2, 1.0, 1); glTexCoord4f(1, 0, 0, Q); glVertex2f( 1, -1);
glColor4f(0.2, 1.0, 0.2, 1); glTexCoord4f(1, 1, 0, Q); glVertex2f( 1, 1);
glColor4f(1.0, 0.2, 0.2, 1); glTexCoord4f(0, 1, 0, Q); glVertex2f(-1, 1);
glEnd();
glPopMatrix();
glutSwapBuffers();
}
static void Reshape( int width, int height )
{
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glFrustum( -1.0, 1.0, -1.0, 1.0, 5.0, 25.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glTranslatef( 0.0, 0.0, -8.0 );
}
static void SpecialKey( int key, int x, int y )
{
float step = 3.0;
(void) x;
(void) y;
switch (key) {
case GLUT_KEY_UP:
Xrot += step;
break;
case GLUT_KEY_DOWN:
Xrot -= step;
break;
case GLUT_KEY_LEFT:
Yrot += step;
break;
case GLUT_KEY_RIGHT:
Yrot -= step;
break;
}
glutPostRedisplay();
}
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( void )
{
static const char *modulate2D =
"!!ARBfp1.0\n"
"TEMP R0;\n"
"TEX R0, fragment.texcoord[0], texture[0], 2D; \n"
"MUL result.color, R0, fragment.color; \n"
"END"
;
GLuint modulateProg;
GLuint Texture;
if (!glutExtensionSupported("GL_ARB_fragment_program")) {
printf("Error: GL_ARB_fragment_program not supported!\n");
exit(1);
}
printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
/* Setup the fragment program */
glGenProgramsARB(1, &modulateProg);
glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, modulateProg);
glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
strlen(modulate2D), (const GLubyte *)modulate2D);
printf("glGetError = 0x%x\n", (int) glGetError());
printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
(char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
assert(glIsProgramARB(modulateProg));
glEnable(GL_FRAGMENT_PROGRAM_ARB);
/* Load texture */
glGenTextures(1, &Texture);
glBindTexture(GL_TEXTURE_2D, Texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
printf("Error: couldn't load texture image file %s\n", TEXTURE_FILE);
exit(1);
}
/* XXX this enable shouldn't really be needed!!! */
glEnable(GL_TEXTURE_2D);
glClearColor(.3, .3, .3, 0);
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowPosition( 0, 0 );
glutInitWindowSize( 250, 250 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
glutCreateWindow(argv[0]);
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutSpecialFunc( SpecialKey );
glutDisplayFunc( Display );
Init();
glutMainLoop();
return 0;
}
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