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'''OpenGL extension ARB.texture_cube_map
This module customises the behaviour of the
OpenGL.raw.GL.ARB.texture_cube_map to provide a more
Python-friendly API
Overview (from the spec)
This extension provides a new texture generation scheme for cube
map textures. Instead of the current texture providing a 1D, 2D,
or 3D lookup into a 1D, 2D, or 3D texture image, the texture is a
set of six 2D images representing the faces of a cube. The (s,t,r)
texture coordinates are treated as a direction vector emanating from
the center of a cube. At texture generation time, the interpolated
per-fragment (s,t,r) selects one cube face 2D image based on the
largest magnitude coordinate (the major axis). A new 2D (s,t) is
calculated by dividing the two other coordinates (the minor axes
values) by the major axis value. Then the new (s,t) is used to
lookup into the selected 2D texture image face of the cube map.
Unlike a standard 1D, 2D, or 3D texture that have just one target,
a cube map texture has six targets, one for each of its six 2D texture
image cube faces. All these targets must be consistent, complete,
and have equal width and height (ie, square dimensions).
This extension also provides two new texture coordinate generation modes
for use in conjunction with cube map texturing. The reflection map
mode generates texture coordinates (s,t,r) matching the vertex's
eye-space reflection vector. The reflection map mode
is useful for environment mapping without the singularity inherent
in sphere mapping. The normal map mode generates texture coordinates
(s,t,r) matching the vertex's transformed eye-space
normal. The normal map mode is useful for sophisticated cube
map texturing-based diffuse lighting models.
The intent of the new texgen functionality is that an application using
cube map texturing can use the new texgen modes to automatically
generate the reflection or normal vectors used to look up into the
cube map texture.
An application note: When using cube mapping with dynamic cube
maps (meaning the cube map texture is re-rendered every frame),
by keeping the cube map's orientation pointing at the eye position,
the texgen-computed reflection or normal vector texture coordinates
can be always properly oriented for the cube map. However if the
cube map is static (meaning that when view changes, the cube map
texture is not updated), the texture matrix must be used to rotate
the texgen-computed reflection or normal vector texture coordinates
to match the orientation of the cube map. The rotation can be
computed based on two vectors: 1) the direction vector from the cube
map center to the eye position (both in world coordinates), and 2)
the cube map orientation in world coordinates. The axis of rotation
is the cross product of these two vectors; the angle of rotation is
the arcsin of the dot product of these two vectors.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/ARB/texture_cube_map.txt
'''
from OpenGL import platform, constants, constant, arrays
from OpenGL import extensions, wrapper
from OpenGL.GL import glget
import ctypes
from OpenGL.raw.GL.ARB.texture_cube_map import *
### END AUTOGENERATED SECTION
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