NAME

edgepaint - edge coloring to disambiguate crossing edges

SYNOPSIS

[ options ] [ -o outfile ] [ files ]

DESCRIPTION

edgepaint takes as input a graph in DOT format with node position information (the pos attribute) and colors the edges in a manner making it easier to tell them apart.

OPTIONS

The following options are supported:

--accuracy=e: Accuracy with which to find the maximally different coloring for each node with regard to its neighbors. Default e = 0.01.
--angle=a: Color two edges differently if their incidence angle is less than a degrees. Default a = 15.
--random_seed=s: Random seed to use. s must be an integer. If s is negative, we do |s| iterations with different seeds and pick the best.
--lightness=l1,l2: Only applies for the "lab" color scheme: l1 and l2 must integers, with 0 <= l1 <= l2 <=100. By default, we use "0,70".
--share_endpoint: If this option is specified, edges that share a node are not considered in conflict if they are close to parallel but are on the opposite sides of the node (around 180 degree).
-o f: Write output to file f (default: stdout).
--color_scheme=c: Specifies the color scheme. This can be "rgb", "gray", "lab" (default); or a comma-separated list of RGB colors in hex (e.g., "#ff0000,#aabbed,#eeffaa") representing a palette; or a string specifying a Brewer color scheme (e.g., "accent7"; see https://graphviz.org/doc/info/colors.html#brewer).
-v: Turns on verbose mode.
-?: Print usage and exit.

BUGS

At present, edgepaint does not handle graphs with loops or directed multiedges. So, a graph with edges a -> b and b -> a is acceptable, but not if it has edges a -> b and a -> b or a -- b and a -- b. Ports are ignored in this analysis, so having a.x -> b and a.y -> b is also not supported.

AUTHOR

Yifan Hu <yifanhu@yahoo.com>