HELP Xcolour_to_rgb                               David Young, Feb 1994

Xcolour_to_rgb(colour) -> (r, g, b)
        The red, green and blue  components of the colour specified  are
        returned. The argument colour may be a string or word containing
        one  of  the  colour  names  in  REF*XCOLOURS,  or  a   colour
        specification of the form '#RGB' where each of R, G and B is a 1
        to 4 digit  hexadecimal integer  (all of the  same length).  The
        argument may  also be  a  3-element vector,  in which  case  its
        components are  returned.  If colour  cannot  be  interpreted, 3
        false values are returned.

The procedure works by consulting the rgb.txt file from which the colour
database is derived. (It  would be better to  interrogate the X  server,
but there does not seem  to be a standard way  to do this.) The  rgb.txt
file seems to be of no fixed abode, so the procedure looks in a  variety
of  places   for   it.  The   list   of   path  names   is   stored   in
Xcolour_to_rgb_filelist, so the default list can be seen by executing

    Xcolour_to_rgb_filelist =>

If the  rgb.txt file  lives somewhere  else, you  can assign  a list  of
strings to Xcolour_to_rgb_filelist to tell the procedure where to look.


--- $popvision/help/Xcolour_to_rgb
--- Copyright University of Sussex 1994. All rights reserved.
