writemask(3G) writemask(3G)
NAME
writemask - grants write permission to available bitplanes
SPECIFICATION
C writemask(wtm)
Colorindex wtm;
FORTRAN subroutine writem(wtm)
integer*4 wtm
DESCRIPTION
writemask protects bitplanes, in the current drawing mode,
that are reserved for special uses from ordinary drawing
routines. wtm is a mask with 1 bit per available bitplane.
Wherever there are ones (1s) in the writemask, the
corresponding bits in the color index are written into the
bitplanes. Zeros (0s) 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
drawmode, RGBwritemask, color
Programming Guide, Section 6.7, Writemasks
Page 1 (printed 8/20/87)