Another interesting d3.js example is Bostock’s rainbow geodesic.
I wanted to understand exactly how it worked, so I went slowly through the source code, removing anything
I thought uneeded, and playing with how things fit together. It uses the d3.geodesic plugin for splitting up
the sphere into faces, d3.hsl for colour, d3.geo.orthographic to project onto a sphere, and d3.geom.polygon
for working out areas of the triangles. The d3.js source code is very worthwhile for understanding all of
this.
As an alteration, I added a timer that cycles through geodesic spheres with different subdivisions.