NAME

writemask − grants write permission to available bitplanes

SPECIFICATION

C
writemask(wtm)
Colorindex wtm;

FORTRAN
subroutine writem(wtm)
integer*4 wtm

Pascal
procedure writemask(wtm: Colorindex);

DESCRIPTION

writemask protects bitplanes that are reserved for special uses from ordinary drawing routines.  wtm is a mask with 1 bit per available bitplane.  Wherever there are ones in the writemask, the corresponding bits in the color index are written into the bitplanes.  Zeros in the writemask mark bitplanes as read-only.  These bitplanes will not be changed, regardless of the bits in the color. 

Use RGBwritemask in RGB mode. 

SEE ALSO

color, RGBwritemask Programming Guide, Section 6.3, Colors and Writemasks

Version 3.6  —  December 20, 1987