progs/tests/arbvptorus.c

   1 /*
   2  * A lit, rotating torus via vertex program
   3  */
   4
   5 #include <assert.h>
   6 #include <string.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <math.h>
  10 #define GL_GLEXT_PROTOTYPES
  11 #include <GL/glut.h>
  12
  13 static float Xrot = 0.0, Yrot = 0.0, Zrot = 0.0;
  14 static GLboolean Anim = GL_TRUE;
  15
  16
  17 static void Idle( void )
  18 {
  19    Xrot += .3;
  20    Yrot += .4;
  21    Zrot += .2;
  22    glutPostRedisplay();
  23 }
  24
  25
  26 static void Display( void )
  27 {
  28    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
  29
  30    glPushMatrix();
  31       glRotatef(Xrot, 1, 0, 0);
  32       glRotatef(Yrot, 0, 1, 0);
  33       glRotatef(Zrot, 0, 0, 1);
  34       glutSolidTorus(0.75, 2.0, 10, 20);
  35    glPopMatrix();
  36
  37    glutSwapBuffers();
  38 }
  39
  40
  41 static void Reshape( int width, int height )
  42 {
  43    glViewport( 0, 0, width, height );
  44    glMatrixMode( GL_PROJECTION );
  45    glLoadIdentity();
  46    glFrustum( -2.0, 2.0, -2.0, 2.0, 5.0, 25.0 );
  47    glMatrixMode( GL_MODELVIEW );
  48    glLoadIdentity();
  49    glTranslatef( 0.0, 0.0, -12.0 );
  50 }
  51
  52
  53 static void Key( unsigned char key, int x, int y )
  54 {
  55    (void) x;
  56    (void) y;
  57    switch (key) {
  58       case ' ':
  59          Xrot = Yrot = Zrot = 0;
  60          break;
  61       case 'a':
  62          Anim = !Anim;
  63          if (Anim)
  64             glutIdleFunc(Idle);
  65          else
  66             glutIdleFunc(NULL);
  67          break;
  68       case 'z':
  69          Zrot -= 5.0;
  70          break;
  71       case 'Z':
  72          Zrot += 5.0;
  73          break;
  74       case 27:
  75          exit(0);
  76          break;
  77    }
  78    glutPostRedisplay();
  79 }
  80
  81
  82 static void SpecialKey( int key, int x, int y )
  83 {
  84    const GLfloat step = 3.0;
  85    (void) x;
  86    (void) y;
  87    switch (key) {
  88       case GLUT_KEY_UP:
  89          Xrot -= step;
  90          break;
  91       case GLUT_KEY_DOWN:
  92          Xrot += step;
  93          break;
  94       case GLUT_KEY_LEFT:
  95          Yrot -= step;
  96          break;
  97       case GLUT_KEY_RIGHT:
  98          Yrot += step;
  99          break;
 100    }
 101    glutPostRedisplay();
 102 }
 103
 104
 105 static void Init( void )
 106 {
 107    GLint errno;
 108    GLuint prognum;
 109
 110    /* borrowed from an nvidia demo:
 111     * c[0..3] = modelview matrix
 112     * c[4..7] = invtrans modelview matrix
 113     * c[32] = light pos
 114     * c[35] = diffuse color
 115     */
 116    static const char prog[] =
 117       "!!ARBvp1.0\n"
 118       "OPTION ARB_position_invariant ;"
 119       "TEMP R0, R1; \n"
 120
 121       "# normal x MV-1T -> lighting normal\n"
 122       "DP3   R1.x, state.matrix.modelview.invtrans.row[0], vertex.normal ;\n"
 123       "DP3   R1.y, state.matrix.modelview.invtrans.row[1], vertex.normal;\n"
 124       "DP3   R1.z, state.matrix.modelview.invtrans.row[2], vertex.normal;\n"
 125
 126       "DP3   R0, program.local[32], R1;                  # L.N\n"
 127 #if 0
 128       "MUL   result.color.xyz, R0, program.local[35] ;   # col = L.N * diffuse\n"
 129 #else
 130       "MUL   result.color.primary.xyz, R0, program.local[35] ;   # col = L.N * diffuse\n"
 131 #endif
 132       "MOV   result.texcoord, vertex.texcoord;\n"
 133       "END";
 134
 135    if (!glutExtensionSupported("GL_ARB_vertex_program")) {
 136       printf("Sorry, this program requires GL_ARB_vertex_program");
 137       exit(1);
 138    }
 139
 140
 141    glGenProgramsARB(1, &prognum);
 142
 143    glBindProgramARB(GL_VERTEX_PROGRAM_ARB, prognum);
 144    glProgramStringARB(GL_VERTEX_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
 145                         strlen(prog), (const GLubyte *) prog);
 146
 147    assert(glIsProgramARB(prognum));
 148    errno = glGetError();
 149    printf("glGetError = %d\n", errno);
 150    if (errno != GL_NO_ERROR)
 151    {
 152       GLint errorpos;
 153
 154       glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorpos);
 155       printf("errorpos: %d\n", errorpos);
 156       printf("%s\n", (char *)glGetString(GL_PROGRAM_ERROR_STRING_ARB));
 157    }
 158
 159    /* Light position */
 160    glProgramLocalParameter4fARB(GL_VERTEX_PROGRAM_ARB, 32, 2, 2, 4, 1);
 161    /* Diffuse material color */
 162    glProgramLocalParameter4fARB(GL_VERTEX_PROGRAM_ARB, 35, 0.25, 0, 0.25, 1);
 163
 164    glEnable(GL_VERTEX_PROGRAM_ARB);
 165    glEnable(GL_DEPTH_TEST);
 166    glClearColor(0.3, 0.3, 0.3, 1);
 167 }
 168
 169
 170 int main( int argc, char *argv[] )
 171 {
 172    glutInit( &argc, argv );
 173    glutInitWindowPosition( 0, 0 );
 174    glutInitWindowSize( 250, 250 );
 175    glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
 176    glutCreateWindow(argv[0]);
 177    glutReshapeFunc( Reshape );
 178    glutKeyboardFunc( Key );
 179    glutSpecialFunc( SpecialKey );
 180    glutDisplayFunc( Display );
 181    if (Anim)
 182       glutIdleFunc(Idle);
 183    Init();
 184    glutMainLoop();
 185    return 0;
 186 }