| | '''OpenGL extension NV.register_combiners |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.NV.register_combiners to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | NVIDIA's next-generation graphics processor and its derivative |
| | designs support an extremely configurable mechanism know as "register |
| | combiners" for computing fragment colors. |
| | |
| | The register combiner mechanism is a significant redesign of NVIDIA's |
| | original TNT combiner mechanism as introduced by NVIDIA's RIVA |
| | TNT graphics processor. Familiarity with the TNT combiners will |
| | help the reader appreciate the greatly enhanced register combiners |
| | functionality (see the NV_texture_env_combine4 OpenGL extension |
| | specification for this background). The register combiner mechanism |
| | has the following enhanced functionality: |
| | |
| | The numeric range of combiner computations is from [-1,1] |
| | (instead of TNT's [0,1] numeric range), |
| | |
| | The set of available combiner inputs is expanded to include the |
| | secondary color, fog color, fog factor, and a second combiner |
| | constant color (TNT's available combiner inputs consist of |
| | only zero, a single combiner constant color, the primary color, |
| | texture 0, texture 1, and, in the case of combiner 1, the result |
| | of combiner 0). |
| | |
| | Each combiner variable input can be independently scaled and |
| | biased into several possible numeric ranges (TNT can only |
| | complement combiner inputs). |
| | |
| | Each combiner stage computes three distinct outputs (instead |
| | TNT's single combiner output). |
| | |
| | The output operations include support for computing dot products |
| | (TNT has no support for computing dot products). |
| | |
| | After each output operation, there is a configurable scale and bias |
| | applied (TNT's combiner operations builds in a scale and/or bias |
| | into some of its combiner operations). |
| | |
| | Each input variable for each combiner stage is fetched from any |
| | entry in a combiner register set. Moreover, the outputs of each |
| | combiner stage are written into the register set of the subsequent |
| | combiner stage (TNT could only use the result from combiner 0 as |
| | a possible input to combiner 1; TNT lacks the notion of an |
| | input/output register set). |
| | |
| | The register combiner mechanism supports at least two general |
| | combiner stages and then a special final combiner stage appropriate |
| | for applying a color sum and fog computation (TNT provides two |
| | simpler combiner stages, and TNT's color sum and fog stages are |
| | hard-wired and not subsumed by the combiner mechanism as in register |
| | combiners). |
| | |
| | The register combiners fit into the OpenGL pipeline as a rasterization |
| | processing stage operating in parallel to the traditional OpenGL |
| | texture environment, color sum, AND fog application. Enabling this |
| | extension bypasses OpenGL's existing texture environment, color |
| | sum, and fog application processing and instead use the register |
| | combiners. The combiner and texture environment state is orthogonal |
| | so modifying combiner state does not change the traditional OpenGL |
| | texture environment state and the texture environment state is |
| | ignored when combiners are enabled. |
| | |
| | OpenGL application developers can use the register combiner mechanism |
| | for very sophisticated shading techniques. For example, an |
| | approximation of Blinn's bump mapping technique can be achieved with |
| | the combiner mechanism. Additionally, multi-pass shading models |
| | that require several passes with unextended OpenGL 1.2 functionality |
| | can be implemented in several fewer passes with register combiners. |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/NV/register_combiners.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.register_combiners import * |
| | from OpenGL.raw.GL.NV.register_combiners import _EXTENSION_NAME |
| |
|
| | def glInitRegisterCombinersNV(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
|
| | |
| | glCombinerParameterfvNV=wrapper.wrapper(glCombinerParameterfvNV).setInputArraySize( |
| | 'params', None |
| | ) |
| | |
| | glCombinerParameterivNV=wrapper.wrapper(glCombinerParameterivNV).setInputArraySize( |
| | 'params', None |
| | ) |
| | glGetCombinerInputParameterfvNV=wrapper.wrapper(glGetCombinerInputParameterfvNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | glGetCombinerInputParameterivNV=wrapper.wrapper(glGetCombinerInputParameterivNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | glGetCombinerOutputParameterfvNV=wrapper.wrapper(glGetCombinerOutputParameterfvNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | glGetCombinerOutputParameterivNV=wrapper.wrapper(glGetCombinerOutputParameterivNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | glGetFinalCombinerInputParameterfvNV=wrapper.wrapper(glGetFinalCombinerInputParameterfvNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | glGetFinalCombinerInputParameterivNV=wrapper.wrapper(glGetFinalCombinerInputParameterivNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | |
