To begin familiarizing yourself with the way that Jitter objects use Open GL for 3D animation, read as many as you can of the Jitter Tutorials numbered 30-34.

Study the following examples of Jitter objects that enable 3D animation with Open GL.

Create a sphere in Open GL
Display a video on a shape in OpenGL
Apply a texture to a shape in OpenGL
Display a video on a plane in OpenGL
Alphablend a videoplane in OpenGL

You can also take a look at the Max Documentation reference manual listing of the attributes and messages that are common to all the Open GL objects in Jitter.