osx man page for glsamplecoverage

GLSAMPLECOVERAGE(3G)						    OpenGL 3.3						      GLSAMPLECOVERAGE(3G)

NAME
       glSampleCoverage - specify multisample coverage parameters

C SPECIFICATION
       void glSampleCoverage(GLclampf value, GLboolean invert);

PARAMETERS
       value
	   Specify a single floating-point sample coverage value. The value is clamped to the range 0 1. The initial value is 1.0.

       invert
	   Specify a single boolean value representing if the coverage masks should be inverted.  GL_TRUE and GL_FALSE are accepted. The initial
	   value is GL_FALSE.

DESCRIPTION
       Multisampling samples a pixel multiple times at various implementation-dependent subpixel locations to generate antialiasing effects.
       Multisampling transparently antialiases points, lines, polygons, and images if it is enabled.

       value is used in constructing a temporary mask used in determining which samples will be used in resolving the final fragment color. This
       mask is bitwise-anded with the coverage mask generated from the multisampling computation. If the invert flag is set, the temporary mask is
       inverted (all bits flipped) and then the bitwise-and is computed.

       If an implementation does not have any multisample buffers available, or multisampling is disabled, rasterization occurs with only a single
       sample computing a pixel's final RGB color.

       Provided an implementation supports multisample buffers, and multisampling is enabled, then a pixel's final color is generated by combining
       several samples per pixel. Each sample contains color, depth, and stencil information, allowing those operations to be performed on each
       sample.

ASSOCIATED GETS
       glGet() with argument GL_SAMPLE_COVERAGE_VALUE

       glGet() with argument GL_SAMPLE_COVERAGE_INVERT

       glIsEnabled() with argument GL_MULTISAMPLE

       glIsEnabled() with argument GL_SAMPLE_ALPHA_TO_COVERAGE

       glIsEnabled() with argument GL_SAMPLE_ALPHA_TO_ONE

       glIsEnabled() with argument GL_SAMPLE_COVERAGE

SEE ALSO
       glEnable()

COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see
       http://oss.sgi.com/projects/FreeB/.

OpenGL 3.3							    03/08/2011						      GLSAMPLECOVERAGE(3G)