Faster

[Fil]

Ideas for later:

• change the arrays into typed arrays when possible (edges => edges2, etc) in the delaunay part
• use spherical trig for rotation & projection (instead of geoRotation+geoStereographic) ✓
• use spherical trig for checking if a triangle is clockwise or CCW (instead of geoArea!) ✓

[mbostock]

Another small optimization is using d3.geoStereographicRaw (or inline the definition) instead of d3.geoStereographic.

[mourner]

Skimming through the code, I also recommend:

• Using flat arrays for points — e.g. [x, y, x, y, ... instead of [[x, y], [x, y], ....
• Avoiding array allocations as much as possible. This includes chained array.map and slice. Inspect each occurrence of allocating methods and try to rewrite for less allocations (e.g. collapse chained function-style transformation into a single for loop).

[Fil]

4b9aee7 uses a direct formula for the stereographic

[Fil]

A good reference presentation :)
https://www.dotconferences.com/2019/12/vladimir-agafonkin-algorithmic-performance-optimization-in-practice