| '''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 ) |
|
|
|
|
| |
