| '''OpenGL extension NV.fragment_program4 |
| |
| This module customises the behaviour of the |
| OpenGL.raw.GL.NV.fragment_program4 to provide a more |
| Python-friendly API |
| |
| Overview (from the spec) |
| |
| This extension builds on the common assembly instruction set |
| infrastructure provided by NV_gpu_program4, adding fragment |
| program-specific features. |
| |
| This extension provides interpolation modifiers to fragment program |
| attributes allowing programs to specify that specified attributes be |
| flat-shaded (constant over a primitive), centroid-sampled (multisample |
| rendering), or interpolated linearly in screen space. The set of input |
| and output bindings provided includes all bindings supported by |
| ARB_fragment_program. Additional input bindings are provided to determine |
| whether fragments were generated by front- or back-facing primitives |
| ("fragment.facing"), to identify the individual primitive used to generate |
| the fragment ("primitive.id"), and to determine distances to user clip |
| planes ("fragment.clip[n]"). Additionally generic input attributes allow |
| a fragment program to receive a greater number of attributes from previous |
| pipeline stages than possible using only the pre-defined fixed-function |
| attributes. |
| |
| By and large, programs written to ARB_fragment_program can be ported |
| directly by simply changing the program header from "!!ARBfp1.0" to |
| "!!NVfp4.0", and then modifying instructions to take advantage of the |
| expanded feature set. There are a small number of areas where this |
| extension is not a functional superset of previous fragment program |
| extensions, which are documented in the NV_gpu_program4 specification. |
| |
| The official definition of this extension is available here: |
| http://www.opengl.org/registry/specs/NV/fragment_program4.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.NV.fragment_program4 import * |
| from OpenGL.raw.GL.NV.fragment_program4 import _EXTENSION_NAME |
|
|
| def glInitFragmentProgram4NV(): |
| '''Return boolean indicating whether this extension is available''' |
| from OpenGL import extensions |
| return extensions.hasGLExtension( _EXTENSION_NAME ) |
|
|
|
|
| |
