| | '''OpenGL extension NV.register_combiners2 |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.NV.register_combiners2 to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | The NV_register_combiners extension provides a powerful fragment |
| | coloring mechanism. This specification extends the register combiners |
| | functionality to support more color constant values that are unique |
| | for each general combiner stage. |
| | |
| | The base register combiners functionality supports only two color |
| | constants. These two constants are available in every general |
| | combiner stage and in the final combiner. |
| | |
| | When many general combiner stages are supported, more than two |
| | unique color constants is often required. The obvious way to extend |
| | the register combiners is to add several more color constant |
| | registers. But adding new unique color constant registers is |
| | expensive for hardware implementation because every color constant |
| | register must be available as an input to any stage. |
| | |
| | In practice however, it is the total set of general combiner stages |
| | that requires more color constants, not each and every individual |
| | general combiner stage. Each individual general combiner stage |
| | typically requires only one or two color constants. |
| | |
| | By keeping two color constant registers but making these two registers |
| | contain two unique color constant values for each general combiner |
| | stage, the hardware expense of supporting multiple color constants |
| | is minimized. Additionally, this scheme scales appropriately as |
| | more general combiner stages are added. |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/NV/register_combiners2.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_combiners2 import * |
| | from OpenGL.raw.GL.NV.register_combiners2 import _EXTENSION_NAME |
| |
|
| | def glInitRegisterCombiners2NV(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
|
| | |
| | glCombinerStageParameterfvNV=wrapper.wrapper(glCombinerStageParameterfvNV).setInputArraySize( |
| | 'params', None |
| | ) |
| | glGetCombinerStageParameterfvNV=wrapper.wrapper(glGetCombinerStageParameterfvNV).setOutput( |
| | 'params',size=_glgets._glget_size_mapping,pnameArg='pname',orPassIn=True |
| | ) |
| | |
