Took the time today to hunt a bug in my Delaunay triangulator. The blue edges are the ones which are not locally Delaunay (something is wrong). It seems there was an oversight in Guibas & Stolfi's Delaunay Paper, or maybe I was reading it wrong. I found & fixed the problem. I had the idea of using the (now (more) correct) Delaunay triangulator to outline point clouds. In the video I'm simply hiding all edges that are longer than some constant that is tuned to the granularity of the input point cloud.