Glut Example

from ctypes import *
import sys

import pygame
from pygame.locals import *

from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *

def compile_shader(source, shader_type):
    shader = glCreateShader(shader_type)
    source = c_char_p(source)
    length = c_int(-1)
    glShaderSource(shader, 1, byref(source), byref(length))
    glCompileShader(shader)

    status = c_int()
    glGetShaderiv(shader, GL_COMPILE_STATUS, byref(status))
    if not status.value:
        print_log(shader)
        glDeleteShader(shader)
        raise ValueError('Shader compilation failed')
    return shader

def compile_program(vertex_source, fragment_source):
    vertex_shader = None
    fragment_shader = None
    program = glCreateProgram()

    if vertex_source:
        vertex_shader = compile_shader(vertex_source, GL_VERTEX_SHADER)
        glAttachShader(program, vertex_shader)
    if fragment_source:
        fragment_shader = compile_shader(fragment_source, GL_FRAGMENT_SHADER)
        glAttachShader(program, fragment_shader)

    glLinkProgram(program)

    if vertex_shader:
        glDeleteShader(vertex_shader)
    if fragment_shader:
        glDeleteShader(fragment_shader)

    return program

def print_log(shader):
    length = c_int()
    glGetShaderiv(shader, GL_INFO_LOG_LENGTH, byref(length))

    if length.value > 0:
        log = create_string_buffer(length.value)
        glGetShaderInfoLog(shader, length, byref(length), log)
        print(sys.stderr, log.value)

if __name__ == '__main__':
    glutInit(sys.argv)
    width, height = 640, 480
    pygame.init()
    pygame.display.set_mode((width, height), OPENGL | DOUBLEBUF)

    program = compile_program('''
    // Vertex program
    varying vec3 pos;
    void main() {
        pos = gl_Vertex.xyz;
        gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
    }
    ''', '''
    // Fragment program
    varying vec3 pos;
    void main() {
        gl_FragColor.rgb = pos.xyz;
    }
    ''')

    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    gluPerspective(90.0, width / float(height), 1.0, 100.0)
    glMatrixMode(GL_MODELVIEW)
    glEnable(GL_DEPTH_TEST)

    quit = False
    angle = 0
    while not quit:
        for e in pygame.event.get():
            if e.type in (QUIT, KEYDOWN):
                quit = True
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
        glLoadIdentity()
        glTranslate(0.0, 0.0, -2.5)
        glRotate(angle, 0.0, 1.0, 0.0)
        glUseProgram(program)
        glutSolidTeapot(1.0)
        angle += 0.1
        pygame.display.flip()