| | '''OpenGL extension SGIX.instruments |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.SGIX.instruments to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | This extension allows the gathering and return of performance |
| | measurements from within the graphics pipeline by adding |
| | instrumentation. |
| | |
| | There are two reasons to do this. The first is as a part of some |
| | type of fixed-frame-rate load management scheme. If we know that |
| | the pipeline is stalled or struggling to process the amount of |
| | data we have given it so far, we can reduce the level of detail of |
| | the remaining objects in the current frame or the next frame, or |
| | adjust the framebuffer resolution for the next frame if we have a |
| | video-zoom capability available. We can call this type of |
| | instrumentation Load Monitoring. |
| | |
| | The second is for performance tuning and debugging of an |
| | application. It might tell us how many triangles were culled or |
| | clipped before being rasterized. We can call this simply Tuning. |
| | |
| | Load Monitoring requires that the instrumentation and the access |
| | of the measurements be efficient, otherwise the instrumentation |
| | itself will reduce performance more than any load-management |
| | scheme could hope to offset. Tuning does not have the same |
| | requirements. |
| | |
| | The proposed extension adds a call to setup a measurements return |
| | buffer, similar to FeedbackBuffer but with an asynchrounous |
| | behavior to prevent filling the pipeline with NOP's while waiting |
| | for the data to be returned. |
| | |
| | Note that although the extension has been specified without any |
| | particular instruments, defining either a device dependent or |
| | device independent instrument should be as simple as introducing |
| | an extension consisting primarily of a new enumerant to identify |
| | the instrument. |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/SGIX/instruments.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.SGIX.instruments import * |
| | from OpenGL.raw.GL.SGIX.instruments import _EXTENSION_NAME |
| |
|
| | def glInitInstrumentsSGIX(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
|
| | glInstrumentsBufferSGIX=wrapper.wrapper(glInstrumentsBufferSGIX).setOutput( |
| | 'buffer',size=lambda x:(x,),pnameArg='size',orPassIn=True |
| | ) |
| | glPollInstrumentsSGIX=wrapper.wrapper(glPollInstrumentsSGIX).setOutput( |
| | 'marker_p',size=(1,),orPassIn=True |
| | ) |
| | |
