OpenGL.GL.ATI.envmap_bumpmap

OpenGL extension ATI.envmap_bumpmap

This module customises the behaviour of the OpenGL.raw.GL.ATI.envmap_bumpmap to provide a more Python-friendly API

Overview (from the spec)

This extension adds environment mapped bump mapping (EMBM) to the GL. The method exposed by this extension is to use a dependent texture read on a bumpmap (du,dv) texture to offset the texture coordinates read into a map on another texture unit. This (du,dv) offset is also rotated through a user-specified rotation matrix to get the texture coordinates into the appropriate space.

A new texture format is introduced in order for specifying the (du,dv) bumpmap texture. This map represents -1 <= du,dv <= 1 offsets to be applied to the texture coordinates used to read into the base map. Additionally, the (du,dv) offsets are transformed by a rotation matrix that this extension allows the user to specify. Further, a new color operation is added to EXT_texture_env_combine to specify both that bumpmapping is enabled and which texture unit to apply the bump offset to.

The official definition of this extension is available here: http://www.opengl.org/registry/specs/ATI/envmap_bumpmap.txt