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'''OpenGL extension MESAX.texture_stack
This module customises the behaviour of the
OpenGL.raw.GL.MESAX.texture_stack to provide a more
Python-friendly API
Overview (from the spec)
There are a number of circumstances where an application may wish to
blend two textures out of a larger set of textures. Moreover, in some
cases the selected textures may vary on a per-fragment basis within
a polygon. Several examples include:
1. High dynamic range textures. The application stores several
different "exposures" of an image as different textures. On a
per-fragment basis, the application selects which exposures are
used.
2. A terrain engine where the altitude of a point determines the
texture applied to it. If the transition is from beach sand to
grass to rocks to snow, the application will store each texture
in a different texture map, and dynamically select which two
textures to blend at run-time.
3. Storing short video clips in textures. Each depth slice is a
single frame of video.
Several solutions to this problem have been proposed, but they either
involve using a separate texture unit for each texture map or using 3D
textures without mipmaps. Both of these options have major drawbacks.
This extension provides a third alternative that eliminates the major
drawbacks of both previous methods. A new texture target,
TEXTURE_2D_STACK, is added that functions identically to TEXTURE_3D in
all aspects except the sizes of the non-base level images. In
traditional 3D texturing, the size of the N+1 LOD is half the size
of the N LOD in all three dimensions. For the TEXTURE_2D_STACK target,
the height and width of the N+1 LOD is halved, but the depth is the
same for all levels of detail. The texture then becomes a "stack" of
2D textures. The per-fragment texel is selected by the R texture
coordinate.
References:
http://www.opengl.org/discussion_boards/cgi_directory/ultimatebb.cgi?ubb=get_topic;f=3;t=011557
http://www.opengl.org/discussion_boards/cgi_directory/ultimatebb.cgi?ubb=get_topic;f=3;t=000516
http://www.opengl.org/discussion_boards/cgi_directory/ultimatebb.cgi?ubb=get_topic;f=3;t=011903
http://www.delphi3d.net/articles/viewarticle.php?article=terraintex.htm
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/MESAX/texture_stack.txt
'''
from OpenGL import platform, constants, constant, arrays
from OpenGL import extensions, wrapper
from OpenGL.GL import glget
import ctypes
from OpenGL.raw.GL.MESAX.texture_stack import *
### END AUTOGENERATED SECTION
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