| | '''OpenGL extension NV.parameter_buffer_object2 |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.NV.parameter_buffer_object2 to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | This extension builds on the NV_parameter_buffer_object extension to |
| | provide additional flexibility in sourcing data from buffer objects. |
| | |
| | The original NV_parameter_buffer_object (PaBO) extension provided the |
| | ability to bind buffer objects to a set of numbered binding points and |
| | access them in assembly programs as though they were arrays of 32-bit |
| | scalars (via the BUFFER variable type) or arrays of four-component vectors |
| | with 32-bit scalar components (via the BUFFER4 variable type). However, |
| | the functionality it provided had some significant limits on flexibility. |
| | Since any given buffer binding point could be used either as a BUFFER or |
| | BUFFER4, but not both, programs couldn't do both 32- and 128-bit fetches |
| | from a single binding point. Additionally, No support was provided for |
| | 8-, 16-, or 64-bit fetches, though they could be emulated using a larger |
| | loads, with bitfield operations and/or write masking to put components in |
| | the right places. Indexing was supported, but strides were limited to 4- |
| | and 16-byte multiples, depending on whether BUFFER or BUFFER4 is used. |
| | |
| | This new extension provides the buffer variable declaration type CBUFFER |
| | to specify a buffer that is treated as an array of bytes, rather than an |
| | array of words or vectors. The LDC instruction allows programs to extract |
| | a vector of data from a CBUFFER variable, using a size and component count |
| | specified in the opcode modifier. 1-, 2-, and 4-component fetches are |
| | supported. The LDC instruction supports byte offsets using normal array |
| | indexing mechanisms; both run-time and immediate offsets are supported. |
| | Offsets used for a buffer object fetch are required to be aligned to the |
| | size of the fetch (1, 2, 4, 8, or 16 bytes). |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/NV/parameter_buffer_object2.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.parameter_buffer_object2 import * |
| | from OpenGL.raw.GL.NV.parameter_buffer_object2 import _EXTENSION_NAME |
| |
|
| | def glInitParameterBufferObject2NV(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
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| |
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| | |
