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'''OpenGL extension SGI.cushion
This module customises the behaviour of the
OpenGL.raw.GLX.SGI.cushion to provide a more
Python-friendly API
Overview (from the spec)
This extension is directed at constant frame-rate applications. Such
applications are written to ensure that a new image is generated every
N video frame periods, where N is itself a small constant integer.
If the application is unable to generate a frame within N video frame
periods, it is said to have dropped a frame. Dropping a frame is a
*bad thing*.
Constant frame-rate applications make every effort to avoid dropping
frames. In particular, they monitor the utilization of graphics
resources during the rendering of the current frame in order to predict
the behavior of subsequent frames. If such prediction indicates that
a frame may be dropped, the rendering complexity of the frame is
reduced (e.g. by using models of lower geometric resolution) so as to
avoid the overload condition.
Unfortunately, because exact prediction is not possible, and because
there is no elasticity in the buffering of images, it is necessary
for constant frame-rate applications to under utilize the graphics
hardware. This extension adds elasticity to the buffering of completed
images, in order to allow constant frame-rate applications to make full
use of the available graphics computation without dropping frames.
It further allows this elasticity to be controlled by the application in
order to minimize the introduction of latency that could otherwise
occur.
Applications that will benefit from this extension include simulation,
walk-through, and multimedia playback.
WARNING - Silicon Graphics has filed for patent protection for some
of the techniques described in this extension document.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/SGI/cushion.txt
'''
from OpenGL import platform, constant, arrays
from OpenGL import extensions, wrapper
import ctypes
from OpenGL.raw.GLX import _types, _glgets
from OpenGL.raw.GLX.SGI.cushion import *
from OpenGL.raw.GLX.SGI.cushion import _EXTENSION_NAME
def glInitCushionSGI():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
### END AUTOGENERATED SECTION
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