How do I style the ports of record based nodes in GraphViz?

Question

I\'m feeding this simple input script defining record based nodes to dot in order to create a SVG from it (the SVG part actually doesn\'t matter):

graph mygr         


        

Answer 1

HTML-like labels give you a lot of flexibility in formatting labels. This code:

graph mygraph{
  node [shape=record, fontsize=10, fontname=Arial];
  rankdir=TB;
  ranksep=0.5;
  rank=max;
  splines=true;
  overlap=false;
  mindist=0.2;
  d1 [shape=none, margin=0, label=<
    <table border="0" cellborder="1" cellspacing="0" cellpadding="4">
        <tr><td colspan="2">d1</td></tr>
        <tr><td port="0">0</td><td>1</td></tr>
    </table>>];
  d2 [shape=none, margin=0, label=<
    <table border="0" cellborder="1" cellspacing="0" cellpadding="4">
        <tr><td colspan="4">d2</td></tr>
        <tr><td port="0">0</td><td bgcolor="green">1</td><td bgcolor="orange">2</td><td>3</td></tr>
    </table>>];
  d1:0 -- d2:0[color=blue, penwidth=3, tooltip="d1:0 -- d2:0", URL="#"];
}

Produces this graph:

Note the use of the port attribute to identify the port.