set the blend color
|red, green, blue, alpha||
specify the components of GL_BLEND_COLOR
The GL_BLEND_COLOR may be used to calculate the source and destination blending factors. The color components are clamped to the range before being stored. See glBlendFunc for a complete description of the blending operations. Initially the GL_BLEND_COLOR is set to (0, 0, 0, 0).
glGet with an argument of GL_BLEND_COLOR
Copyright 1991-2006 Silicon Graphics, Inc. Copyright 2010-2013 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/ .