gvcolor

GVCOLOR(1)                  General Commands Manual                 GVCOLOR(1)

NAME
       gvcolor - flow colors through a ranked digraph

SYNOPSIS
       gvcolor [ files ]

USAGE
       dot file.gv | gvcolor | dot -T<format>

DESCRIPTION
       gvcolor  (previously known as colorize) is a filter that sets node col-
       ors from initial seed values.  Colors flow along  edges  from  tail  to
       head,  and  are averaged (as HSB vectors) at nodes.  The graph must al-
       ready have been processed by dot.  Appropriate choice of initial colors
       yields  drawings  in  which node colors help to emphasize logical rela-
       tionships between nodes, even when they are spread  far  apart  in  the
       layout.

       Initial  colors  must be set externally, using the color attribute of a
       node.  It is often effective to assign colors to a few  key  source  or
       sink  nodes,  manually  setting their colors by editing the graph file.
       Color names are as in dot(1): symbolic names or  RGB  triples.   It  is
       best to choose some easily-distinguished but related colors; not neces-
       sarily spaced evenly around the color wheel.  For example,  blue_green,
       green, and light_yellow looks better than red, green, blue.

       Certain  graph attributes control the gvcolor algorithm.  flow=back re-
       verses the flow of colors from heads to  tails.   saturation=.1,.9  (or
       any  two numbers between 0 and 1) adjusts the color saturation linearly
       from least to greatest rank.  If Defcolor is set, this color  value  is
       applied to any node not otherwise colored.

EXIT STATUS
       The following exit values are returned:

       0   Successful completion.

       1   If nodes of the graph do not possess a ``pos'' attribute.

BUGS
       It would be nice to make the program work without relying on an initial
       pass through dot.

AUTHORS
       Stephen C. North <north@research.att.com>
       Emden R. Gansner <erg@research.att.com>

SEE ALSO
       gc(1), dot(1), gvpr(1), ccomps(1), sccmap(1), tred(1), libgraph(3)

                                 21 March 2001                      GVCOLOR(1)