wmpack(3G)

NAME
     wmpack - specifies RGBA writemask with a single packed integer

FORTRAN 77 SPECIFICATION
     subroutine wmpack(pack)
     integer*4 pack

PARAMETERS
     pack   expects a packed integer containing the RGBA (red, green, blue,
            alpha) values you want to assign as the current write mask.
            Expressed in hexadecimal, the format of the packed integer is
            $aabbggrr, where:

               aa   is the alpha value,
               bb   is the blue value,
               gg   is the green value, and
               rr   is the red value.

            RGBA component values range from 0 to $FF (255).

DESCRIPTION
     wmpack sets the red, green, blue, and alpha write mask components of the
     currently active GL framebuffer, one of normal, popup, overlay, or
     underlay as specified by drawmo.  The current framebuffer must be in RGB
     mode for the wmpack command to be applicable.  All drawing into the color
     bitplanes of the current framebuffer is masked by the current write mask.
     Write mask components are retained in each draw mode, so when a draw mode
     is re-entered, the red, green, blue, and alpha masks are reset to the
     last values specified in that draw mode.

     Each write mask component is an 8-bit mask, which allows changes only to
     bitplanes corresponding to ones in the mask.  For example,
     wmpack($FF0000F0) allows changes only to the 4 most significant bits of
     red, and to all the bits of alpha.

     It is an error to call wmpack while the current framebuffer is in color
     map mode.

     The write mask components of all framebuffers in RGB mode are set to $FF
     when gconfi is called.

SEE ALSO
     cpack, drawmo, gRGBma, RGBmod

NOTE
     Because only the normal framebuffer currently supports RGB mode, wmpack
     should be called only while draw mode is NORMAL.  Use getgde to determine
     whether RGB mode is available in draw mode NORMAL.

     On Impact and Infinite Reality only whole components can be masked.  RGB
     and A can be completely masked or not masked at all.