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'''OpenGL extension OES.primitive_bounding_box
This module customises the behaviour of the
OpenGL.raw.GLES2.OES.primitive_bounding_box to provide a more
Python-friendly API
Overview (from the spec)
On tile-based architectures, transformed primitives are generally written
out to memory before rasterization, and then read back from memory for each
tile they intersect. When geometry expands during transformation due to
tessellation or one-to-many geometry shaders, the external bandwidth
required grows proportionally. This extension provides a way for
implementations to know which tiles incoming geometry will intersect before
fully transforming (and expanding) the geometry. This allows them to only
store the unexpanded geometry in memory, and perform expansion on-chip for
each intersected tile.
New state is added to hold an axis-aligned bounding box which is assumed to
contain any geometry submitted. An implementation is allowed to ignore any
portions of primitives outside the bounding box; thus if a primitive extends
outside of a tile into a neighboring tile that the bounding box didn't
intersect, the implementation is not required to render those portions. The
tessellation control shader is optionally able to specify a per-patch
bounding box that overrides the bounding box state for primitives generated
from that patch, in order to provide tighter bounds.
The typical usage is that an application will have an object-space bounding
volume for a primitive or group of primitives, either calculated at runtime
or provided with the mesh by the authoring tool or content pipeline. It will
transform this volume to clip space, compute an axis-aligned bounding box
that contains the transformed bounding volume, and provide that at either
per-patch or per-draw granularity.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/OES/primitive_bounding_box.txt
'''
from OpenGL import platform, constant, arrays
from OpenGL import extensions, wrapper
import ctypes
from OpenGL.raw.GLES2 import _types, _glgets
from OpenGL.raw.GLES2.OES.primitive_bounding_box import *
from OpenGL.raw.GLES2.OES.primitive_bounding_box import _EXTENSION_NAME
def glInitPrimitiveBoundingBoxOES():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
### END AUTOGENERATED SECTION
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