UML diagram for OpenGL ES 2.0 state?

Question

Can anybody provide a UML diagram describing the OpenGL ES 2.0 state machine?

Ideally, such a diagram should describe thing such as textures have width, height, type, internal format, etc.; programs have attached shaders, may or may not be linked, have uniforms, etc.; et al.

The reason I would be very interested is because I often find myself wondering things such as:

• Are texture parameters (set with glTexParameter) associated with the current texture, or texture unit?
• Is the set of enabled generalized vector attributes part of the currently bound VBO? Or part of the current program? Or global?

Having a UML diagram of OpenGL would be tremendously useful in answering these things at a glance rather than having to pour through obscene amounts of documentation to try to figure out how all the different components play together.

I realize looking for this is a long shot because I imagine it a tremendous effort to put together. Still, I think it would be tremendously useful. Even a partial answer could help a lot. Likewise, a diagram of some version of OpenGL other than the one I'm targeting (ES 2.0) would be useful.

Answer 1

The website for the OpenGL Insights book provides a UML state diagram for the whole rendering pipeline for both OpenGL 4.2 and OpenGL ES 2.0: http://openglinsights.com/pipeline.html

This diagram roughly shows the interaction of the stages and what GL objects are involved in each state and it shows the chapter of the specification that describe these objects.

What the diagram doesn't show is the state of the objects involved, but you can find that in the specification itself. In the OpenGL ES 2.0 specification chapter 6.2 all objects and aspects are listed with their state and how you can access it.

So, if you annotate the state diagram with the table numbers from the specification you more or less have everything you want.