openGL_PBO

#include <iostream>
#ifndef GL_GLEXT_PROTOTYPES
#define GL_GLEXT_PROTOTYPES
#endif
#include <OpenGL/gl.h>
#include <OpenGL/glu.h>
#include <OpenGL/glext.h>
#include <GLUT/glut.h>
using namespace std;


unsigned int   vbo[2];
short          positions[12] = { 1, -1, 0,
    1,  1, 0,
    -1, -1, 0,
    -1,  1, 0};
unsigned short indices[4]  = {0,1,2,3};

static void init ()
{
    glGenBuffers (2, vbo);
    cout << "Created vbo = " << vbo[0] << ", " << vbo[1] << "\n";
    glBindBuffer (GL_ARRAY_BUFFER, vbo[0]);
    glBufferData (GL_ARRAY_BUFFER, sizeof(positions), positions, GL_STATIC_DRAW);
    glBindBuffer (GL_ELEMENT_ARRAY_BUFFER, vbo[1]);
    glBufferData (GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
}

static void display ()
{
    glClearColor (0,0,1.f,1.f);
    glClear      (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

    glEnableClientState  (GL_VERTEX_ARRAY);

    // 頂点データ
    glBindBuffer         (GL_ARRAY_BUFFER, vbo[0]);
    glVertexPointer      (3, GL_SHORT, 0, 0);

    // インデックス
    glBindBuffer         (GL_ELEMENT_ARRAY_BUFFER, vbo[1]);

    //glDrawElements(GL_TRIANGLE_STRIP, sizeof(indices)/sizeof(indices[0]),GL_UNSIGNED_SHORT, 0);
    glDrawElements(GL_POINTS, sizeof(indices)/sizeof(indices[0]),GL_UNSIGNED_SHORT, 0);

    glDisableClientState (GL_VERTEX_ARRAY);

    glutSwapBuffers();
}

static void reshape (int w, int h)
{
    glViewport     (0, 0, w, h);
    glMatrixMode   (GL_PROJECTION);
    glLoadIdentity ();
    glOrtho        (-2, 2, -2, 2, -2, 2);
}


static void keyboard(unsigned char key, int x, int y)
{
    if (key == 113) {
        exit (0);
    }
    glutPostRedisplay();
}

/**
 * メインプログラム
 */
int main(int argc, char *argv[])
{
    glutInit            (&argc, argv);
    glutInitDisplayMode (GLUT_RGBA | GLUT_DEPTH | GLUT_DOUBLE);
    glutCreateWindow    (argv[0]);
    glutDisplayFunc     (display);
    glutReshapeFunc     (reshape);

    init ();

    glutKeyboardFunc   (keyboard);
    glutMainLoop       ();
    return 0;
}