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'''OpenGL extension SGI.color_matrix |
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This module customises the behaviour of the |
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OpenGL.raw.GL.SGI.color_matrix to provide a more |
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Python-friendly API |
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Overview (from the spec) |
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This extension adds a 4x4 matrix stack to the pixel transfer path. The |
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matrix operates on RGBA pixel groups, using the equation |
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C' = MC, |
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where |
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|R| |
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C = |G| |
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|B| |
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|A| |
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and M is the 4x4 matrix on the top of the color matrix stack. After |
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the matrix multiplication, each resulting color component is scaled |
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and biased by a programmed amount. Color matrix multiplication follows |
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convolution (and the scale, and bias that are associated with |
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convolution.) |
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The color matrix can be used to reassign and duplicate color components. |
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It can also be used to implement simple color space conversions. |
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The official definition of this extension is available here: |
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http://www.opengl.org/registry/specs/SGI/color_matrix.txt |
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''' |
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from OpenGL import platform, constant, arrays |
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from OpenGL import extensions, wrapper |
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import ctypes |
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from OpenGL.raw.GL import _types, _glgets |
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from OpenGL.raw.GL.SGI.color_matrix import * |
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from OpenGL.raw.GL.SGI.color_matrix import _EXTENSION_NAME |
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def glInitColorMatrixSGI(): |
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'''Return boolean indicating whether this extension is available''' |
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from OpenGL import extensions |
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return extensions.hasGLExtension( _EXTENSION_NAME ) |
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