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'''OpenGL extension ARB.framebuffer_sRGB |
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This module customises the behaviour of the |
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OpenGL.raw.GL.ARB.framebuffer_sRGB to provide a more |
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Python-friendly API |
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Overview (from the spec) |
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Conventionally, OpenGL assumes framebuffer color components are stored |
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in a linear color space. In particular, framebuffer blending is a |
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linear operation. |
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The sRGB color space is based on typical (non-linear) monitor |
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characteristics expected in a dimly lit office. It has been |
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standardized by the International Electrotechnical Commission (IEC) |
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as IEC 61966-2-1. The sRGB color space roughly corresponds to 2.2 |
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gamma correction. |
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This extension adds a framebuffer capability for sRGB framebuffer |
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update and blending. When blending is disabled but the new sRGB |
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updated mode is enabled (assume the framebuffer supports the |
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capability), high-precision linear color component values for red, |
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green, and blue generated by fragment coloring are encoded for sRGB |
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prior to being written into the framebuffer. When blending is enabled |
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along with the new sRGB update mode, red, green, and blue framebuffer |
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color components are treated as sRGB values that are converted to |
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linear color values, blended with the high-precision color values |
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generated by fragment coloring, and then the blend result is encoded |
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for sRGB just prior to being written into the framebuffer. |
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The primary motivation for this extension is that it allows OpenGL |
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applications to render into a framebuffer that is scanned to a monitor |
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configured to assume framebuffer color values are sRGB encoded. |
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This assumption is roughly true of most PC monitors with default |
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gamma correction. This allows applications to achieve faithful |
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color reproduction for OpenGL rendering without adjusting the |
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monitor's gamma correction. |
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The official definition of this extension is available here: |
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http://www.opengl.org/registry/specs/ARB/framebuffer_sRGB.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.ARB.framebuffer_sRGB import * |
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from OpenGL.raw.GL.ARB.framebuffer_sRGB import _EXTENSION_NAME |
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def glInitFramebufferSrgbARB(): |
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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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