1/* Basic VBO */
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#define ELTOBJ 0
12
13struct {
14   GLfloat pos[3];
15   GLubyte color[4];
16} verts[] =
17{
18   { {  0.9, -0.9, 0.0 },
19     { 0x00, 0x00, 0xff, 0x00 }
20   },
21
22   { {  0.9,  0.9, 0.0 },
23     { 0x00, 0xff, 0x00, 0x00 }
24   },
25
26   { { -0.9,  0.9, 0.0 },
27     { 0xff, 0x00, 0x00, 0x00 }
28   },
29
30   { { -0.9, -0.9, 0.0 },
31     { 0xff, 0xff, 0xff, 0x00 }
32   },
33};
34
35GLuint indices[] = { 1, 2, 3 };
36
37GLuint arrayObj, elementObj;
38
39static void Init( void )
40{
41   GLint errnum;
42   GLuint prognum;
43
44   static const char *prog1 =
45      "!!ARBvp1.0\n"
46      "MOV  result.color, vertex.color;\n"
47      "MOV  result.position, vertex.position;\n"
48      "END\n";
49
50   glGenProgramsARB(1, &prognum);
51   glBindProgramARB(GL_VERTEX_PROGRAM_ARB, prognum);
52   glProgramStringARB(GL_VERTEX_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
53		      strlen(prog1), (const GLubyte *) prog1);
54
55   assert(glIsProgramARB(prognum));
56   errnum = glGetError();
57   printf("glGetError = %d\n", errnum);
58   if (errnum != GL_NO_ERROR)
59   {
60      GLint errorpos;
61
62      glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorpos);
63      printf("errorpos: %d\n", errorpos);
64      printf("%s\n", (char *)glGetString(GL_PROGRAM_ERROR_STRING_ARB));
65   }
66
67
68   glEnableClientState( GL_VERTEX_ARRAY );
69   glEnableClientState( GL_COLOR_ARRAY );
70
71   glGenBuffersARB(1, &arrayObj);
72   glBindBufferARB(GL_ARRAY_BUFFER_ARB, arrayObj);
73   glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(verts), verts, GL_STATIC_DRAW_ARB);
74
75#if ELTOBJ
76   glGenBuffersARB(1, &elementObj);
77   glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, elementObj);
78   glBufferDataARB(GL_ELEMENT_ARRAY_BUFFER_ARB, sizeof(indices), indices, GL_STATIC_DRAW_ARB);
79#endif
80
81   glVertexPointer( 3, GL_FLOAT, sizeof(verts[0]), 0 );
82   glColorPointer( 4, GL_UNSIGNED_BYTE, sizeof(verts[0]), (void *)(3*sizeof(float)) );
83
84}
85
86
87
88static void Display( void )
89{
90   glClearColor(0.3, 0.3, 0.3, 1);
91   glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
92
93   glEnable(GL_VERTEX_PROGRAM_ARB);
94
95#if ELTOBJ
96   glDrawRangeElements( GL_TRIANGLES, 1, 3, 3, GL_UNSIGNED_INT, NULL );
97#else
98   glDrawRangeElements( GL_TRIANGLES, 1, 3, 3, GL_UNSIGNED_INT, indices );
99#endif
100
101   glFlush();
102}
103
104
105static void Reshape( int width, int height )
106{
107   glViewport( 0, 0, width, height );
108   glMatrixMode( GL_PROJECTION );
109   glLoadIdentity();
110   glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
111   glMatrixMode( GL_MODELVIEW );
112   glLoadIdentity();
113   /*glTranslatef( 0.0, 0.0, -15.0 );*/
114}
115
116
117static void Key( unsigned char key, int x, int y )
118{
119   (void) x;
120   (void) y;
121   switch (key) {
122      case 27:
123         exit(0);
124         break;
125   }
126   glutPostRedisplay();
127}
128
129
130
131
132int main( int argc, char *argv[] )
133{
134   glutInit( &argc, argv );
135   glutInitWindowPosition( 0, 0 );
136   glutInitWindowSize( 250, 250 );
137   glutInitDisplayMode( GLUT_RGB | GLUT_SINGLE | GLUT_DEPTH );
138   glutCreateWindow(argv[0]);
139   glewInit();
140   glutReshapeFunc( Reshape );
141   glutKeyboardFunc( Key );
142   glutDisplayFunc( Display );
143   Init();
144   glutMainLoop();
145   return 0;
146}
147