progs/fp/tri-sge2.c

   1
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <stdlib.h>
   5 #define GL_GLEXT_PROTOTYPES
   6 #include <GL/glut.h>
   7 #include "GL/gl.h"
   8
   9
  10
  11 static void Init( void )
  12 {
  13    static const char *modulate2D =
  14       "!!ARBfp1.0\n"
  15       "TEMP R0;\n"
  16       "TEMP R1;\n"
  17       "SGE R0, fragment.color, fragment.color.yzxw; \n"
  18       "SGE R1, fragment.color, fragment.color.zxyw; \n"
  19       "MUL R0, R0, R1; \n"
  20       "MUL result.color, R0, fragment.color; \n"
  21       "END"
  22       ;
  23    GLuint modulateProg;
  24
  25    if (!glutExtensionSupported("GL_ARB_fragment_program")) {
  26       printf("Error: GL_ARB_fragment_program not supported!\n");
  27       exit(1);
  28    }
  29    printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
  30
  31    /* Setup the fragment program */
  32    glGenProgramsARB(1, &modulateProg);
  33    glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, modulateProg);
  34    glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
  35                         strlen(modulate2D), (const GLubyte *)modulate2D);
  36
  37    printf("glGetError = 0x%x\n", (int) glGetError());
  38    printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
  39           (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
  40
  41    glEnable(GL_FRAGMENT_PROGRAM_ARB);
  42
  43    glClearColor(.3, .3, .3, 0);
  44 }
  45
  46 static void Reshape(int width, int height)
  47 {
  48
  49     glViewport(0, 0, (GLint)width, (GLint)height);
  50
  51     glMatrixMode(GL_PROJECTION);
  52     glLoadIdentity();
  53     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  54     glMatrixMode(GL_MODELVIEW);
  55 }
  56
  57 static void Key(unsigned char key, int x, int y)
  58 {
  59
  60     switch (key) {
  61       case 27:
  62         exit(1);
  63       default:
  64         return;
  65     }
  66
  67     glutPostRedisplay();
  68 }
  69
  70 static void Draw(void)
  71 {
  72    glClear(GL_COLOR_BUFFER_BIT);
  73
  74    glBegin(GL_TRIANGLES);
  75    glColor3f(0,0,1);
  76    glVertex3f( 0.9, -0.9, -30.0);
  77    glColor3f(1,0,0);
  78    glVertex3f( 0.9,  0.9, -30.0);
  79    glColor3f(0,1,0);
  80    glVertex3f(-0.9,  0.0, -30.0);
  81    glEnd();
  82
  83    glFlush();
  84
  85
  86 }
  87
  88
  89 int main(int argc, char **argv)
  90 {
  91     GLenum type;
  92
  93     glutInit(&argc, argv);
  94
  95
  96
  97     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
  98
  99     type = GLUT_RGB;
 100     type |= GLUT_SINGLE;
 101     glutInitDisplayMode(type);
 102
 103     if (glutCreateWindow("First Tri") == GL_FALSE) {
 104         exit(1);
 105     }
 106
 107     Init();
 108
 109     glutReshapeFunc(Reshape);
 110     glutKeyboardFunc(Key);
 111     glutDisplayFunc(Draw);
 112     glutMainLoop();
 113         return 0;
 114 }