Tag
geometric-primitives
- Apr 12, 2026 Convex Hulls by Monotone Chain How a lexicographic sort followed by two stack scans produces the convex hull in O(n log n), and why the collinearity rule decides which points survive. algorithms
- Apr 22, 2025 Detecting Segment Intersections with Orientation Tests How four orientation signs decide whether two segments cross, why the collinear cases need separate handling, and where the all-pairs test stops being affordable. algorithms
- Dec 14, 2024 Point in Polygon: Crossing Number and Winding Number Why two standard containment tests disagree on self-intersecting polygons, how each handles rays through vertices, and what the boundary rule costs. algorithms