| '''OpenGL extension AMD.query_buffer_object |
| |
| This module customises the behaviour of the |
| OpenGL.raw.GL.AMD.query_buffer_object to provide a more |
| Python-friendly API |
| |
| Overview (from the spec) |
| |
| Statistics about the operation of the OpenGL pipeline, such as the number |
| of samples that passed the depth test, the elapsed time between two events |
| or the number of vertices written to a transform feedback buffer may |
| be retrieved from the GL through query objects. The current value of a |
| query object may be retrieved by the application through the OpenGL API. |
| Should the result returned by the API be required for use in a shader, |
| it must be passed back to the GL via a program uniform or some other |
| mechanism. This requires a round-trip from the GPU to the CPU and back. |
| |
| This extension introduces a mechanism whereby the current value of a query |
| result may be retrieved into a buffer object instead of client memory. |
| This allows the query result to be made available to a shader without a |
| round-trip to the CPU for example by subsequently using the buffer object |
| as a uniform buffer, texture buffer or other data store visible to the |
| shader. This functionality may also be used to place the results of |
| many query objects into a single, large buffer and then map or otherwise |
| read back the entire buffer at a later point in time, avoiding a per-query |
| CPU-GPU synchronization event. |
| |
| The result of any query object type supported by the GL implementation |
| may be retrieved into a buffer object. The implementation will determine |
| the most efficient method of copying the query result to the buffer. |
| |
| The official definition of this extension is available here: |
| http://www.opengl.org/registry/specs/AMD/query_buffer_object.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.AMD.query_buffer_object import * |
| from OpenGL.raw.GL.AMD.query_buffer_object import _EXTENSION_NAME |
|
|
| def glInitQueryBufferObjectAMD(): |
| '''Return boolean indicating whether this extension is available''' |
| from OpenGL import extensions |
| return extensions.hasGLExtension( _EXTENSION_NAME ) |
|
|
|
|
| |
