edgepaint

Colorize edges of one or more graph layouts (that already have layout information) to clarify crossing edges

$ edgepaint [path/to/layout1.gv] [path/to/layout2.gv ...] > [path/to/output.gv]

$ edgepaint -color-scheme=[accent7] [path/to/layout.gv] > [path/to/output.gv]

$ dot [path/to/input.gv] | edgepaint | dot -T [png] > [path/to/output.png]

$ edgepaint -?

[ options ] [ -o outfile ] [ files ]

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.

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.

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.

gvmap(1), sfdp(1), neato(1), dot(1)

Yifan Hu <yifanhu@yahoo.com>