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'''OpenGL extension EXT.shader_pixel_local_storage
This module customises the behaviour of the
OpenGL.raw.GLES2.EXT.shader_pixel_local_storage to provide a more
Python-friendly API
Overview (from the spec)
Techniques such as deferred shading and deferred lighting are often
implemented by attaching multiple color render targets to a framebuffer
object, rendering the required intermediate data, and then sampling from
this data as textures. While flexible, this approach consumes a large
amount of external memory bandwidth, which is at a premium on mobile
devices.
Observing that the intermediate or "G-buffer" data is often only written to
and read by shaders executing for the same pixel position, tile-based
renderers can offer a more efficient alternative by keeping the data on-GPU.
This allows large amounts of data to be kept per-pixel, with zero external
memory bandwidth impact.
This extension provides a way for applications to pass information between
fragment shader invocations covering the same pixel by introducing the
concept of pixel local storage. Pixel local storage is an on-chip memory
storage that can be efficiently accessed by fragments being processed by
the GL. The format of data stored in the pixel local storage is independent
of the format of the currently attached framebuffer. The data in pixel local
storage is not written back to main memory. Access to pixel local storage
is controlled via glEnable and glDisable. If commands that implicitly or
explicitly flush the GL command stream are issued when pixel local storage
is enabled then the contents of the pixel local storage becomes undefined
for subsequent commands.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/EXT/shader_pixel_local_storage.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.EXT.shader_pixel_local_storage import *
from OpenGL.raw.GLES2.EXT.shader_pixel_local_storage import _EXTENSION_NAME
def glInitShaderPixelLocalStorageEXT():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
### END AUTOGENERATED SECTION
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