NAME

       cmap - format of .cmap files (color maps)

DESCRIPTION

       Color-map files define the mapping between eight-bit color numbers and red, green and blue
       intensities used for those numbers.  They are read by Magic as part of system startup, and
       also  by  the :load and :save commands in color-map windows.  Color-map file names usually
       have the form x.y.z.cmapn, where x is a class  of  technology  files,  y  is  a  class  of
       displays,  z is a class of monitors, and n is a version number (currently 1).  The version
       number will change in the future if the format of color-map files ever changes.  Normally,
       x  and y correspond to the corresponding parts of a display styles file.  For example, the
       color map file mos.7bit.std.cmap1 is used today for most nMOS and  CMOS  technology  files
       using  displays  that support at least seven bits of color per pixel and standard-phosphor
       monitors.  It corresponds to the display styles file mos.7bit.dstyle5.

       Color-map files are stored in ASCII form, with each line containing four decimal  integers
       separated  by white space.  The first three integers are red, green, and blue intensities,
       and the fourth field is a color number.  For current  displays  the  intensities  must  be
       integers  between  0  and 255.  The color numbers must increase from line to line, and the
       last line must have a color number of 255.  The red, green, and blue  intensities  on  the
       first  line  are  used  for all colors from 0 up to and including the color number on that
       line.  For other lines, the intensities on that line are used for all colors starting  one
       color  above the color number on the previous line and continuing up and through the color
       number on the current line.  For example, consider the color map below:

       255     0       0       2
       0       0       255     3
       255     255     255     256

       This color map indicates that colors 0, 1, and 2 are to be red, color 3 is to be blue, and
       all other colors are to be white.

SEE ALSO

       magic(1), dstyle(5)