hilbert
Fast hilbert curve algorithm developed by rawunprotected ported to 64 bit. It includes benchmarks and tests.
| Benchmark | Time | CPU | Iterations |
|---|---|---|---|
| BM_XYToIndex/1 | 2 ns | 2 ns | 389906979 |
| BM_XYToIndex/8 | 2 ns | 2 ns | 362373234 |
| BM_XYToIndex/32 | 2 ns | 2 ns | 364389751 |
| BM_IndexToXY/1 | 2 ns | 2 ns | 428239325 |
| BM_IndexToXY/8 | 2 ns | 2 ns | 430551968 |
| BM_IndexToXY/32 | 2 ns | 2 ns | 434526211 |
All the relevant code is in this header
A discussion can be found here.