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'''OpenGL extension EXT.discard_framebuffer
This module customises the behaviour of the
OpenGL.raw.GLES1.EXT.discard_framebuffer to provide a more
Python-friendly API
Overview (from the spec)
This extension provides a new command, DiscardFramebufferEXT, which
causes the contents of the named framebuffer attachable images to become
undefined. The contents of the specified buffers are undefined until a
subsequent operation modifies the content, and only the modified region
is guaranteed to hold valid content. Effective usage of this command
may provide an implementation with new optimization opportunities.
Some OpenGL ES implementations cache framebuffer images in a small pool
of fast memory. Before rendering, these implementations must load the
existing contents of one or more of the logical buffers (color, depth,
stencil, etc.) into this memory. After rendering, some or all of these
buffers are likewise stored back to external memory so their contents can
be used again in the future. In many applications, some or all of the
logical buffers are cleared at the start of rendering. If so, the
effort to load or store those buffers is wasted.
Even without this extension, if a frame of rendering begins with a full-
screen Clear, an OpenGL ES implementation may optimize away the loading
of framebuffer contents prior to rendering the frame. With this extension,
an application can use DiscardFramebufferEXT to signal that framebuffer
contents will no longer be needed. In this case an OpenGL ES
implementation may also optimize away the storing back of framebuffer
contents after rendering the frame.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/EXT/discard_framebuffer.txt
'''
from OpenGL import platform, constant, arrays
from OpenGL import extensions, wrapper
import ctypes
from OpenGL.raw.GLES1 import _types, _glgets
from OpenGL.raw.GLES1.EXT.discard_framebuffer import *
from OpenGL.raw.GLES1.EXT.discard_framebuffer import _EXTENSION_NAME
def glInitDiscardFramebufferEXT():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
# INPUT glDiscardFramebufferEXT.attachments size not checked against numAttachments
glDiscardFramebufferEXT=wrapper.wrapper(glDiscardFramebufferEXT).setInputArraySize(
'attachments', None
)
### END AUTOGENERATED SECTION
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