Delaunay32
Delaunay32 is a C++17 library for exact, parallel 2D Delaunay triangulation over signed 32-bit integer coordinates. It supports constraints, polygon domains with holes, deterministic duplicate handling, explicit float-to-integer quantization, and serial or shared-memory parallel execution. The author reports roughly 147–150 ms single-threaded and 53–54 ms eight-threaded for one million points on an Apple M1, versus about 540–555 ms for delaunator-cpp and slower results for Triangle and Fade2D.
The Hacker News discussion focused on the useful constrained-Delaunay support and comparisons with Triangle, plus why the API stops at int32: exact incircle predicates already need 128-bit intermediates, while int64 inputs would require roughly 256-bit temporaries. The project is MIT-licensed and includes benchmarks, tests, examples, and SVG/JSON extras.