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'''OpenGL extension KHR.context_flush_control
This module customises the behaviour of the
OpenGL.raw.GL.KHR.context_flush_control to provide a more
Python-friendly API
Overview (from the spec)
OpenGL and OpenGL ES have long supported multiple contexts. The
semantics of switching contexts is generally left to window system
binding APIs such as WGL, GLX and EGL. Most of these APIs (if not all)
specify that when the current context for a thread is changed, the
outgoing context performs an implicit flush of any commands that have
been issued to that point. OpenGL and OpenGL ES define a flush as
sending any pending commands for execution and that this action will
result in their completion in finite time.
This behavior has subtle consequences. For example, if an application is
rendering to the front buffer and switches contexts, it may assume that
any rendering performed thus far will eventually be visible to the user.
With recent introduction of shared memory buffers, there become inumerable
ways in which applications may observe side effects of an implicit flush
(or lack thereof).
In general, a full flush is not the desired behavior of the application.
Nonetheless, applications that switch contexts frequently suffer the
performance consequences of this unless implementations make special
considerations for them, which is generally untenable.
The EGL, GLX, and WGL extensions add new context creation parameters
that allow an application to specify the behavior that is desired when a
context is made non-current, and specifically to opt out of the implicit
flush behavior. The GL extension allows querying the context flush
behavior.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/KHR/context_flush_control.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.KHR.context_flush_control import *
from OpenGL.raw.GL.KHR.context_flush_control import _EXTENSION_NAME
def glInitContextFlushControlKHR():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
### END AUTOGENERATED SECTION
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