gl_example.py

# pip install PyOpenGL OpenGLContext PyVRML97 pydispatcher PIL

from pymol import cmd
from pymol.callback import Callback

import time
from OpenGLContext import testingcontext
BaseContext = testingcontext.getInteractive()
from OpenGL.GL import *
from OpenGL.arrays import vbo
from OpenGLContext.arrays import *
from OpenGL.GL import shaders

import numpy as np

def random_walk(N):
   x = np.random.randn(N + 1, 3).astype('f').cumsum(axis=0)
   x -= x.mean(axis=0)
   return 0.5 * x / x.std()

class myCallback(Callback):
   """Creates a simple vertex shader..."""
   def __init__(self):
      self.rebuild(1 * 1000 * 1000)

   def rebuild(self, nlines):
      self.nlines = nlines
      mygeom = random_walk(nlines) * 10.0
      self.vbo = vbo.VBO(mygeom)

   def __call__(self):
      try:
         self.vbo.bind()
         try:
            glEnableClientState(GL_VERTEX_ARRAY)
            glVertexPointerf(self.vbo)
            glDrawArrays(GL_LINE_STRIP, 0, self.nlines + 1)
         finally:
            self.vbo.unbind()
            glDisableClientState(GL_VERTEX_ARRAY)
      finally:
         pass

walker = myCallback()
cmd.load_callback(walker, 'gl01')