/* * A lit, rotating torus via vertex program */ #include <assert.h> #include <string.h> #include <stdio.h> #include <stdlib.h> #include <math.h> #include <GL/glew.h> #include <GL/glut.h> static float Xrot = 0.0, Yrot = 0.0, Zrot = 0.0; static GLboolean Anim = GL_TRUE; static void Idle( void ) { Xrot += .3; Yrot += .4; Zrot += .2; glutPostRedisplay(); } static void Display( void ) { glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); glPushMatrix(); glRotatef(Xrot, 1, 0, 0); glRotatef(Yrot, 0, 1, 0); glRotatef(Zrot, 0, 0, 1); glutSolidTorus(0.75, 2.0, 10, 20); glPopMatrix(); glutSwapBuffers(); } static void Reshape( int width, int height ) { glViewport( 0, 0, width, height ); glMatrixMode( GL_PROJECTION ); glLoadIdentity(); glFrustum( -2.0, 2.0, -2.0, 2.0, 5.0, 25.0 ); glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); glTranslatef( 0.0, 0.0, -12.0 ); } static void Key( unsigned char key, int x, int y ) { (void) x; (void) y; switch (key) { case ' ': Xrot = Yrot = Zrot = 0; break; case 'a': Anim = !Anim; if (Anim) glutIdleFunc(Idle); else glutIdleFunc(NULL); break; case 'z': Zrot -= 5.0; break; case 'Z': Zrot += 5.0; break; case 27: exit(0); break; } glutPostRedisplay(); } static void SpecialKey( int key, int x, int y ) { const GLfloat 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 Init( void ) { /* borrowed from an nvidia demo: * c[0..3] = modelview matrix * c[4..7] = inverse modelview matrix * c[32] = light pos * c[35] = diffuse color */ static const char prog[] = "!!VP1.0\n" "#Simple transform and diffuse lighting\n" "\n" "DP4 o[HPOS].x, c[0], v[OPOS] ; # object x MVP -> clip\n" "DP4 o[HPOS].y, c[1], v[OPOS] ;\n" "DP4 o[HPOS].z, c[2], v[OPOS] ;\n" "DP4 o[HPOS].w, c[3], v[OPOS] ;\n" "DP3 R1.x, c[4], v[NRML] ; # normal x MV-1T -> lighting normal\n" "DP3 R1.y, c[5], v[NRML] ;\n" "DP3 R1.z, c[6], v[NRML] ;\n" "DP3 R0, c[32], R1 ; # L.N\n" "MUL o[COL0].xyz, R0, c[35] ; # col = L.N * diffuse\n" "MOV o[TEX0], v[TEX0];\n" "END"; if (!glutExtensionSupported("GL_NV_vertex_program")) { printf("Sorry, this program requires GL_NV_vertex_program"); exit(1); } glLoadProgramNV(GL_VERTEX_PROGRAM_NV, 1, strlen(prog), (const GLubyte *) prog); assert(glIsProgramNV(1)); glBindProgramNV(GL_VERTEX_PROGRAM_NV, 1); /* Load the program registers */ glTrackMatrixNV(GL_VERTEX_PROGRAM_NV, 0, GL_MODELVIEW_PROJECTION_NV, GL_IDENTITY_NV); glTrackMatrixNV(GL_VERTEX_PROGRAM_NV, 4, GL_MODELVIEW, GL_INVERSE_TRANSPOSE_NV); /* Light position */ glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 32, 2, 2, 4, 1); /* Diffuse material color */ glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 35, 0.25, 0, 0.25, 1); glEnable(GL_VERTEX_PROGRAM_NV); glEnable(GL_DEPTH_TEST); glClearColor(0.3, 0.3, 0.3, 1); printf("glGetError = %d\n", (int) glGetError()); } 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]); glewInit(); glutReshapeFunc( Reshape ); glutKeyboardFunc( Key ); glutSpecialFunc( SpecialKey ); glutDisplayFunc( Display ); if (Anim) glutIdleFunc(Idle); Init(); glutMainLoop(); return 0; }