Mscgen (http://www.mcternan.me.uk/mscgen/) is a small program that parses Message Sequence Chart descriptions and produces PNG, SVG, EPS or server side image maps (ismaps) as the output. The program and the language it parses are similar to the Graphviz Dot tools.
Using the AsciiDoc mscgen filter, Message Sequence Chart descriptions can be embedded into AsciiDoc documents and processed into either PNG bitmap or SVG vector graphics.
For example this ASCII text:
msc {
arcgradient = 8;
a [label="Client"],b [label="Server"];
a=>b [label="data1"];
a-xb [label="data2"];
a=>b [label="data3"];
a<=b [label="ack1, nack2"];
a=>b [label="data2", arcskip="1"];
|||;
a<=b [label="ack3"];
|||;
}
renders:
More information and examples can be found on the README page.