docs: def on_resize(width, height):
  	"""Setup 3D projection"""
  	glViewport(0, 0, width, height)
  	glMatrixMode(GL_PROJECTION)
  	glLoadIdentity()
  	gluPerspective(30, 1.0*width/height, 0.1, 1000.0)
  	glMatrixMode(GL_MODELVIEW)
  	glLoadIdentity()