OpenGL man pages
glColorMask - enable and disable writing of frame buffer color components
void glColorMask( GLboolean red,
GLboolean alpha )
red, green, blue, alpha
Specify whether red, green, blue, and alpha can or
cannot be written into the frame buffer. The default
values are all GL_TRUE, indicating that the color
components can be written.
glColorMask specifies whether the individual color components in the frame
buffer can or cannot be written. If red is GL_FALSE, for example, no
change is made to the red component of any pixel in any of the color
buffers, regardless of the drawing operation attempted.
Changes to individual bits of components cannot be controlled. Rather,
changes are either enabled or disabled for entire color components.
GL_INVALID_OPERATION is generated if glColorMask is executed between the
execution of glBegin and the corresponding execution of glEnd.
glGet with argument GL_COLOR_WRITEMASK
glGet with argument GL_RGBA_MODE
glColor, glIndex, glIndexMask, glDepthMask, glStencilMask
Fri Dec 6 11:18:03 EST 1996
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