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'''OpenGL extension NV.float_buffer
This module customises the behaviour of the
OpenGL.raw.GL.NV.float_buffer to provide a more
Python-friendly API
Overview (from the spec)
This extension builds upon NV_fragment_program to provide a framebuffer
and texture format that allows fragment programs to read and write
unconstrained floating point data.
In unextended OpenGL, most computations dealing with color or depth
buffers are typically constrained to operate on values in the range [0,1].
Computational results are also typically clamped to the range [0,1].
Color, texture, and depth buffers themselves also hold values mapped to
the range [0,1].
The NV_fragment_program extension provides a general computational model
that supports floating-point numbers constrained only by the precision of
the underlying data types. The quantites computed by fragment programs do
not necessarily correspond in number or in range to conventional
attributes such as RGBA colors or depth values. Because of the range and
precision constraints imposed by conventional fixed-point color buffers,
it may be difficult (if not impossible) to use them to implement certain
multi-pass algorithms.
To enhance the extended range and precision available through fragment
programs, this extension provides floating-point RGBA color buffers that
can be used instead of conventional fixed-point RGBA color buffers. A
floating-point RGBA color buffer consists of one to four floating-point
components stored in the 16- or 32-bit floating-point formats (fp16 or
fp32) defined in the NV_half_float and NV_fragment_program extensions.
When a floating-point color buffer is used, the results of fragment
programs, as written to the "x", "y", "z", and "w" components of the
o[COLR] or o[COLH] output registers, are written directly to the color
buffer without any clamping or modification. Certain per-fragment
operations are bypassed when rendering to floating-point color buffers.
A floating-point color buffer can also be used as a texture map, either by
reading back the contents and then using conventional TexImage calls, or
by using the buffer directly via the ARB_render_texture extension or
the EXT_framebuffer_object extension.
This extension has many uses. Some possible uses include:
(1) Multi-pass algorithms with arbitrary intermediate results that
don't have to be artifically forced into the range [0,1]. In
addition, intermediate results can be written without having to
worry about out-of-range values.
(2) Deferred shading algorithms where an expensive fragment program is
executed only after depth testing is fully complete. Instead, a
simple program is executed, which stores the parameters necessary
to produce a final result. After the entire scene is rendered, a
second pass is executed over the entire frame buffer to execute
the complex fragment program using the results written to the
floating-point color buffer in the first pass. This will save the
cost of applying complex fragment programs to fragments that will
not appear in the final image.
(3) Use floating-point texture maps to evaluate functions with
arbitrary ranges. Arbitrary functions with a finite domain can be
approximated using a texture map holding sample results and
piecewise linear approximation.
There are several significant limitations on the use of floating-point
color buffers. First, floating-point color buffers do not support frame
buffer blending. Second, floating-point texture maps do not support
mipmapping or any texture filtering other than NEAREST. Third,
floating-point texture maps must be 2D, and must use the
NV_texture_rectangle extension.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/NV/float_buffer.txt
'''
from OpenGL import platform, constants, constant, arrays
from OpenGL import extensions, wrapper
from OpenGL.GL import glget
import ctypes
from OpenGL.raw.GL.NV.float_buffer import *
### END AUTOGENERATED SECTION
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