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'''OpenGL extension ARB.shader_storage_buffer_object
This module customises the behaviour of the
OpenGL.raw.GL.ARB.shader_storage_buffer_object to provide a more
Python-friendly API
Overview (from the spec)
This extension provides the ability for OpenGL shaders to perform random
access reads, writes, and atomic memory operations on variables stored in
a buffer object. Application shader code can declare sets of variables
(referred to as "buffer variables") arranged into interface blocks in a
manner similar to that done with uniform blocks in OpenGL 3.1. In both
cases, the values of the variables declared in a given interface block are
taken from a buffer object bound to a binding point associated with the
block. Buffer objects used in this extension are referred to as "shader
storage buffers".
While the capability provided by this extension is similar to that
provided by OpenGL 3.1 and ARB_uniform_buffer_object, there are several
significant differences. Most importantly, shader code is allowed to
write to shader storage buffers, while uniform buffers are always
read-only. Shader storage buffers have a separate set of binding points,
with different counts and size limits. The maximum usable size for shader
storage buffers is implementation-dependent, but its minimum value is
substantially larger than the minimum for uniform buffers.
The ability to write to buffer objects creates the potential for multiple
independent shader invocations to read and write the same underlying
memory. The same issue exists with the ARB_shader_image_load_store
extension provided in OpenGL 4.2, which can write to texture objects and
buffers. In both cases, the specification makes few guarantees related to
the relative order of memory reads and writes performed by the shader
invocations. For ARB_shader_image_load_store, the OpenGL API and shading
language do provide some control over memory transactions; those
mechanisms also affect reads and writes of shader storage buffers. In the
OpenGL API, the glMemoryBarrier() call can be used to ensure that certain
memory operations related to commands issued prior the barrier complete
before other operations related to commands issued after the barrier.
Additionally, the shading language provides the memoryBarrier() function
to control the relative order of memory accesses within individual shader
invocations and provides various memory qualifiers controlling how the
memory corresponding to individual variables is accessed.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/ARB/shader_storage_buffer_object.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.ARB.shader_storage_buffer_object import *
from OpenGL.raw.GL.ARB.shader_storage_buffer_object import _EXTENSION_NAME
def glInitShaderStorageBufferObjectARB():
'''Return boolean indicating whether this extension is available'''
from OpenGL import extensions
return extensions.hasGLExtension( _EXTENSION_NAME )
### END AUTOGENERATED SECTION
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