Shaders aren't that hard

I've been playing with glewpy, and have been able to create, compile and use some simple OpenGL vertex and fragment shaders.

I'm thinking of adding shader type leaves to QGL. Not everyone has shader capable hardware, so the leaves need to be optional, which means they can't exist in the qgl.scene namespace, they will need to be explicitly imported by the programmer.

If shaders are optional, then the render visitor shouldn't need to know about the OpenGL shader implementation. This presents a problem. How do I enable custom leaf execution in the Render and other visitor classes? In it's current state, it is not obvious, as the Render visitor uses a big if/elif block to dispatch leaf drawing operations.

Hmmm.