So the video starts by introducing an isochrone map, and then goes on to do a lot of work to do with warping based on spring between points. This is actually do

So the video starts by introducing an isochrone map, and then goes on to do a lot of work to do with warping based on spring between points. This is actually doing something subtly different than the original idea. The original isochrone has an important constraint, it is drawing the circles based on travel time to a single point. This is important because there is 1 solution to that. You can't generalize that because point B could be 5 minutes from points A and C, but A could be 3 minutes from point C. He gets around this by quantizing - the spring trick, but it does mean the map is meaningfully wrong. Cool looking maps though.