Fork to put labels, following this idea: http://stackoverflow.com/questions/20447106/how-to-center-horizontal-and-vertical-text-along-an-textpath-inside-an-arc-usi
work to be done Need to discover how zoom works, to zoom sliceGroup and not only path
Click on any arc to zoom in. Click in the center to zoom out.
A sunburst is similar to a treemap, except it uses a radial layout. The root node of the tree is at the center, with leaves on the circumference. The area (or angle, depending on implementation) of each arc corresponds to its value. Sunburst design by John Stasko. Data courtesy Jeff Heer.