-  enable and disable writing of frame buffer color compo-
       nents



C SPECIFICATION


PARAMETERS

       _param1, _param2, _param3, _param4
                                        Specify   whether    red,
                                        green,  blue,  and  alpha
                                        can or cannot be  written
                                        into  the  frame  buffer.
                                        The  initial  values  are
                                        all  GL_TRUE,  indicating
                                        that the color components
                                        can be written.


DESCRIPTION

       glColorMask  specifies whether the individual color compo-
       nents in the frame buffer can or cannot  be  written.   If
       _param1 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 con-
       trolled.  Rather, changes are either enabled  or  disabled
       for entire color components.


ERRORS

       GL_INVALID_OPERATION  is  generated if glColorMask is exe-
       cuted between the execution of glBegin and the correspond-
       ing execution of glEnd.


ASSOCIATED GETS

       glGet with argument GL_COLOR_WRITEMASK
       glGet with argument GL_RGBA_MODE


SEE ALSO

       glClear,  glColor,  glColorPointer,  glDepthMask, glIndex,
       glIndexPointer, glIndexMask, glStencilMask



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