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'''OpenGL extension EXT.texture_compression_astc_decode_mode
This module customises the behaviour of the
OpenGL.raw.GLES2.EXT.texture_compression_astc_decode_mode to provide a more
Python-friendly API
Overview (from the spec)
Adaptive Scalable Texture Compression (ASTC) is a texture compression
technology that is exposed by existing extensions and specifications.
The existing specifications require that low dynamic range (LDR)
textures are decompressed to FP16 values per component. In many cases,
decompressing LDR textures to a lower precision intermediate result gives
acceptable image quality. Source material for LDR textures is typically
authored as 8-bit UNORM values, so decoding to FP16 values adds little
value. On the other hand, reducing precision of the decoded result
reduces the size of the decompressed data, potentially improving texture
cache performance and saving power.
The goal of this extension is to enable this efficiency gain on existing
ASTC texture data. This is achieved by giving the application the ability
to select the decoding precision.
Two decoding options are provided by
GL_EXT_texture_compression_astc_decode_mode
- Decode to FP16: This is the default, and matches the required behavior
in existing APIs.
- Decode to UNORM8: This is provided as an option in LDR mode.
If GL_EXT_texture_compression_astc_decode_mode_rgb9e5 is supported, then
a third decoding option is provided:
- Decode to RGB9_E5: This is provided as an option in both LDR and HDR
mode. In this mode, negative values cannot be represented and are
clamped to zero. The alpha component is ignored, and the results
are as if alpha was 1.0.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/EXT/texture_compression_astc_decode_mode.txt
'''
from OpenGL import platform, constant, arrays
from OpenGL import extensions, wrapper
import ctypes
from OpenGL.raw.GLES2 import _types, _glgets
from OpenGL.raw.GLES2.EXT.texture_compression_astc_decode_mode import *
from OpenGL.raw.GLES2.EXT.texture_compression_astc_decode_mode import _EXTENSION_NAME
def glInitTextureCompressionAstcDecodeModeEXT():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
### END AUTOGENERATED SECTION
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