Blender Git Loki

OpenGL: generic inputs for new matrix API

For functions that expect a 4x4 matrix, you can pass in that, or array[16], or float*, or... Casting at each call site can get annoying, and obscures the logic.

The C11 section still needs work, but the non-C11 macros help on the system I tested on (Mac/clang).

Part of T49450