Native bindings to the EXT_bindable_uniform extension.

This extension introduces the concept of bindable uniforms to the OpenGL Shading Language. A uniform variable can be declared bindable, which means that the storage for the uniform is not allocated by the compiler/linker anymore, but is backed by a buffer object. This buffer object is bound to the bindable uniform through the new command UniformBufferEXT(). Binding needs to happen after linking a program object.

Binding different buffer objects to a bindable uniform allows an application to easily use different "uniform data sets", without having to re-specify the data every time.

A buffer object can be bound to bindable uniforms in different program objects. If those bindable uniforms are all of the same type, accessing a bindable uniform in program object A will result in the same data if the same access is made in program object B. This provides a mechanism for 'environment uniforms', uniform values that can be shared among multiple program objects.