1/* GL_ARB_fragment_program texture test */
2
3#include <assert.h>
4#include <string.h>
5#include <stdio.h>
6#include <stdlib.h>
7#include <math.h>
8#include <GL/glew.h>
9#include "glut_wrap.h"
10
11#include "readtex.c"
12
13
14#define TEXTURE_FILE DEMOS_DATA_DIR "girl.rgb"
15
16static GLfloat Xrot = 0.0, Yrot = 0.0, Zrot = 0.0;
17
18#define PI 3.141592
19
20static void Display( void )
21{
22   glClear( GL_COLOR_BUFFER_BIT );
23
24   glPushMatrix();
25   glRotatef(Xrot, 1.0, 0.0, 0.0);
26   glRotatef(Yrot, 0.0, 1.0, 0.0);
27   glRotatef(Zrot, 0.0, 0.0, 1.0);
28
29   glBegin(GL_POLYGON);
30   glTexCoord2f(-PI, 0);   glVertex2f(-1, -1);
31   glTexCoord2f(PI, 0);   glVertex2f( 1, -1);
32   glTexCoord2f(PI, 1);   glVertex2f( 1,  1);
33   glTexCoord2f(-PI, 1);   glVertex2f(-1,  1);
34   glEnd();
35
36   glPopMatrix();
37
38   glutSwapBuffers();
39}
40
41
42static void Reshape( int width, int height )
43{
44   glViewport( 0, 0, width, height );
45   glMatrixMode( GL_PROJECTION );
46   glLoadIdentity();
47   glFrustum( -1.0, 1.0, -1.0, 1.0, 5.0, 25.0 );
48   glMatrixMode( GL_MODELVIEW );
49   glLoadIdentity();
50   glTranslatef( 0.0, 0.0, -8.0 );
51}
52
53
54static void SpecialKey( int key, int x, int y )
55{
56   float step = 3.0;
57   (void) x;
58   (void) y;
59
60   switch (key) {
61      case GLUT_KEY_UP:
62         Xrot += step;
63         break;
64      case GLUT_KEY_DOWN:
65         Xrot -= step;
66         break;
67      case GLUT_KEY_LEFT:
68         Yrot += step;
69         break;
70      case GLUT_KEY_RIGHT:
71         Yrot -= step;
72         break;
73   }
74   glutPostRedisplay();
75}
76
77
78static void Key( unsigned char key, int x, int y )
79{
80   (void) x;
81   (void) y;
82   switch (key) {
83      case 27:
84         exit(0);
85         break;
86   }
87   glutPostRedisplay();
88}
89
90
91static void Init( void )
92{
93   static const char *modulate2D =
94      "!!ARBfp1.0\n"
95      "TEMP R0;\n"
96      "MOV R0, {0,0,0,1};\n"
97      "SCS R0, fragment.texcoord[0].x; \n"
98      "ADD R0, R0, {1.0}.x;\n"
99      "MUL R0, R0, {0.5}.x;\n"
100      "MOV result.color, R0; \n"
101      "END"
102      ;
103   GLuint modulateProg;
104   GLuint Texture;
105
106   if (!glutExtensionSupported("GL_ARB_fragment_program")) {
107      printf("Error: GL_ARB_fragment_program not supported!\n");
108      exit(1);
109   }
110   printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
111
112   /* Setup the fragment program */
113   glGenProgramsARB(1, &modulateProg);
114   glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, modulateProg);
115   glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
116                        strlen(modulate2D), (const GLubyte *)modulate2D);
117
118   printf("glGetError = 0x%x\n", (int) glGetError());
119   printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
120          (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
121   assert(glIsProgramARB(modulateProg));
122
123   glEnable(GL_FRAGMENT_PROGRAM_ARB);
124
125   /* Load texture */
126   glGenTextures(1, &Texture);
127   glBindTexture(GL_TEXTURE_2D, Texture);
128   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
129   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
130   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
131   if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
132      printf("Error: couldn't load texture image file %s\n", TEXTURE_FILE);
133      exit(1);
134   }
135   /* XXX this enable shouldn't really be needed!!! */
136   glEnable(GL_TEXTURE_2D);
137
138   glClearColor(.3, .3, .3, 0);
139}
140
141
142int main( int argc, char *argv[] )
143{
144   glutInit( &argc, argv );
145   glutInitWindowPosition( 0, 0 );
146   glutInitWindowSize( 250, 250 );
147   glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
148   glutCreateWindow(argv[0]);
149   glewInit();
150   glutReshapeFunc( Reshape );
151   glutKeyboardFunc( Key );
152   glutSpecialFunc( SpecialKey );
153   glutDisplayFunc( Display );
154   Init();
155   glutMainLoop();
156   return 0;
157}
158