Transform Callgraph into SVG (similar to Blackfire.io)

On the http://www.typofree.org/articles/an-improved-xhprof-ui/ page I saw nice addition to XHProf that changed both UI (added colors) and functionality (changed callgraph into clickable SVG). This was done in https://github.com/Tuurlijk/xhprof fork.

I wasn't sure how to get only SVG part from it though, because changes to code are massive.