OpenGL extension SGIX.texture_lod_bias
This module customises the behaviour of the
OpenGL.raw.GL.SGIX.texture_lod_bias to provide a more
Overview (from the spec)
This extension modifies the calculation of texture level of detail
parameter LOD, which is represented by the Greek character lambda
in the GL Specification. The LOD equation assumes that a 2^n x 2^m x 2^l
texture is band limited at 2^(n-1), 2^(m-1), 2^(l-1). Often a texture is
oversampled or filtered such that the texture is band limited at lower
frequencies in one or more dimensions. The result is that texture-mapped
primitives appear excessively blurry. This extension provides biases
for n, m, and l in the LOD calculation to to compensate for under or over
sampled texture images. Mipmapped textures can be made to appear sharper or
blurrier by supplying a negative or positive bias respectively.
Examples of textures which can benefit from this LOD control include
video-capture images which are filtered differently horizontally and
vertically; a texture which appears blurry because it is mapped with
a nonuniform scale, such as a road texture which is repeated hundreds of
times in one dimension and only once in the other; and textures which
had to be magnified to a power-of-two for mipmapping.
The official definition of this extension is available here:
|EXTENSION_NAME = 'GL_SGIX_texture_lod_bias'|
GL_TEXTURE_LOD_BIAS_R_SGIX = GL_TEXTURE_LOD_BIAS_R_SGIX
GL_TEXTURE_LOD_BIAS_S_SGIX = GL_TEXTURE_LOD_BIAS_S_SGIX
GL_TEXTURE_LOD_BIAS_T_SGIX = GL_TEXTURE_LOD_BIAS_T_SGIX
__file__ = '/home/mcfletch/pylive/OpenGL/GL/SGIX/texture_lod_bias.pyc'
__name__ = 'OpenGL.GL.SGIX.texture_lod_bias'
__package__ = 'OpenGL.GL.SGIX'