Fiddling with d3.geom.voronoi and a polygon.
The polygon's vertices are fed into the Voronoi layout, that yields the colored regions as output. Also, links are drawn as dashed lines.
Relevant examples by Mike Bostock:
Modified http://d3js.org/d3.v3.min.js to a secure url
https://d3js.org/d3.v3.min.js