This library provides a reliable point-in-polygon test that works with complex polygons including those with holes and self-intersections. Based on Hao's research, it returns `true` for points inside, `false` for points outside, and `0` for points exactly on the edge, while handling floating-point precision issues. It's designed for developers working with geographic data or geometric computations who need robust polygon containment testing that supports GeoJSON-compatible polygon formats.