| | '''OpenGL extension SGIX.fog_offset |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.SGIX.fog_offset to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | This extension allows fragments to look brighter in a foggy |
| | environment, by biasing the fragment eye-coordinate distance prior |
| | to fog computation. A reference point in eye space (rx ry rz) and an offset |
| | amount toward the viewpoint (f_o) are specified. When fog offset is |
| | enabled, the offset amount will be subtracted from the fragment |
| | distance, making objects appear less foggy. |
| | |
| | If fog computation is done in screen-space coordinates under |
| | perspective projection, the reference point is used in adjusting the |
| | fog offset to be correct for fragments whose depth is close to that |
| | point. The reference point should be redefined when it becomes too |
| | far away from the primitives being drawn. Under orthographic |
| | projection, or if fog computation is done in eye-space coordinates, |
| | the reference point is ignored. |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/SGIX/fog_offset.txt |
| | ''' |
| | from OpenGL import platform, constant, arrays |
| | from OpenGL import extensions, wrapper |
| | import ctypes |
| | from OpenGL.raw.GL import _types, _glgets |
| | from OpenGL.raw.GL.SGIX.fog_offset import * |
| | from OpenGL.raw.GL.SGIX.fog_offset import _EXTENSION_NAME |
| |
|
| | def glInitFogOffsetSGIX(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
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| |
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| | |
