| '''OpenGL extension NV.gpu_program5 |
| |
| This module customises the behaviour of the |
| OpenGL.raw.GL.NV.gpu_program5 to provide a more |
| Python-friendly API |
| |
| Overview (from the spec) |
| |
| This specification documents the common instruction set and basic |
| functionality provided by NVIDIA's 5th generation of assembly instruction |
| sets supporting programmable graphics pipeline stages. |
| |
| The instruction set builds upon the basic framework provided by the |
| ARB_vertex_program and ARB_fragment_program extensions to expose |
| considerably more capable hardware. In addition to new capabilities for |
| vertex and fragment programs, this extension provides new functionality |
| for geometry programs as originally described in the NV_geometry_program4 |
| specification, and serves as the basis for the new tessellation control |
| and evaluation programs described in the NV_tessellation_program5 |
| extension. |
| |
| Programs using the functionality provided by this extension should begin |
| with the program headers "!!NVvp5.0" (vertex programs), "!!NVtcp5.0" |
| (tessellation control programs), "!!NVtep5.0" (tessellation evaluation |
| programs), "!!NVgp5.0" (geometry programs), and "!!NVfp5.0" (fragment |
| programs). |
| |
| This extension provides a variety of new features, including: |
| |
| * support for 64-bit integer operations; |
| |
| * the ability to dynamically index into an array of texture units or |
| program parameter buffers; |
| |
| * extending texel offset support to allow loading texel offsets from |
| regular integer operands computed at run-time, instead of requiring |
| that the offsets be constants encoded in texture instructions; |
| |
| * extending TXG (texture gather) support to return the 2x2 footprint |
| from any component of the texture image instead of always returning |
| the first (x) component; |
| |
| * extending TXG to support shadow comparisons in conjunction with a |
| depth texture, via the SHADOW* targets; |
| |
| * further extending texture gather support to provide a new opcode |
| (TXGO) that applies a separate texel offset vector to each of the four |
| samples returned by the instruction; |
| |
| * bit manipulation instructions, including ones to find the position of |
| the most or least significant set bit, bitfield insertion and |
| extraction, and bit reversal; |
| |
| * a general data conversion instruction (CVT) supporting conversion |
| between any two data types supported by this extension; and |
| |
| * new instructions to compute the composite of a set of boolean |
| conditions a group of shader threads. |
| |
| This extension also provides some new capabilities for individual program |
| types, including: |
| |
| * support for instanced geometry programs, where a geometry program may |
| be run multiple times for each primitive; |
| |
| * support for emitting vertices in a geometry program where each vertex |
| emitted may be directed at a specified vertex stream and captured |
| using the ARB_transform_feedback3 extension; |
| |
| * support for interpolating an attribute at a programmable offset |
| relative to the pixel center (IPAO), at a programmable sample number |
| (IPAS), or at the fragment's centroid location (IPAC) in a fragment |
| program; |
| |
| * support for reading a mask of covered samples in a fragment program; |
| |
| * support for reading a point sprite coordinate directly in a fragment |
| program, without overriding a texture coordinate; |
| |
| * support for reading patch primitives and per-patch attributes |
| (introduced by ARB_tessellation_shader) in a geometry program; and |
| |
| * support for multiple output vectors for a single color output in a |
| fragment program (as used by ARB_blend_func_extended). |
| |
| This extension also provides optional support for 64-bit-per-component |
| variables and 64-bit floating-point arithmetic. These features are |
| supported if and only if "NV_gpu_program_fp64" is found in the extension |
| string. |
| |
| This extension incorporates the memory access operations from the |
| NV_shader_buffer_load and NV_parameter_buffer_object2 extensions, |
| originally built as add-ons to NV_gpu_program4. It also provides the |
| following new capabilities: |
| |
| * support for the features without requiring a separate OPTION keyword; |
| |
| * support for indexing into an array of constant buffers using the LDC |
| opcode added by NV_parameter_buffer_object2; |
| |
| * support for storing into buffer objects at a specified GPU address |
| using the STORE opcode, an allowing applications to create READ_WRITE |
| and WRITE_ONLY mappings when making a buffer object resident using the |
| API mechanisms in the NV_shader_buffer_store extension; |
| |
| * storage instruction modifiers to allow loading and storing 64-bit |
| component values; |
| |
| * support for atomic memory transactions using the ATOM opcode, where |
| the instruction atomically reads the memory pointed to by a pointer, |
| performs a specified computation, stores the results of that |
| computation, and returns the original value read; |
| |
| * support for memory barrier transactions using the MEMBAR opcode, which |
| ensures that all memory stores issued prior to the opcode complete |
| prior to any subsequent memory transactions; and |
| |
| * a fragment program option to specify that depth and stencil tests are |
| performed prior to fragment program execution. |
| |
| Additionally, the assembly program languages supported by this extension |
| include support for reading, writing, and performing atomic memory |
| operations on texture image data using the opcodes and mechanisms |
| documented in the "Dependencies on NV_gpu_program5" section of the |
| EXT_shader_image_load_store extension. |
| |
| The official definition of this extension is available here: |
| http://www.opengl.org/registry/specs/NV/gpu_program5.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.gpu_program5 import * |
| from OpenGL.raw.GL.NV.gpu_program5 import _EXTENSION_NAME |
|
|
| def glInitGpuProgram5NV(): |
| '''Return boolean indicating whether this extension is available''' |
| from OpenGL import extensions |
| return extensions.hasGLExtension( _EXTENSION_NAME ) |
|
|
| |
| glProgramSubroutineParametersuivNV=wrapper.wrapper(glProgramSubroutineParametersuivNV).setInputArraySize( |
| 'params', None |
| ) |
| glGetProgramSubroutineParameteruivNV=wrapper.wrapper(glGetProgramSubroutineParameteruivNV).setOutput( |
| 'param',size=_glgets._glget_size_mapping,pnameArg='target',orPassIn=True |
| ) |
| |
