CG-SHOP 2023

2023 Computational Geometry Challenge Accompanying SoCG: Minimum Convex Cover

Problem Description

Literature Review

Relevant Hardness Results

O'Rourke Original NP-Hardness Result

  • Poses problem/Introduces Steiner points
  • Canonical Reduction from 3-SAT

Original NP-Hardness Result for Polygons Without Holes

Extra Hardness of Convex Cover

  • Not verifiable, uber hard!

Heuristic Solutions

Poly-time Approximation Algorithm

  • Uses configurations on a pairwise grid between vertices
  • Makes grid finer by redefining a grid among pairwise points between the original grid, etc
  • Bounds number of configurations, thereby bounding the number of possible interior convex polygons to try

Near Linear Cover of Disjoint Polygons

  • Given disjoint polygons, there exists a unique convexification which has total minimum area and covers all polygons
  • Could use this simple technique to piece together remaining disjoint polygons after taking away large convex polygons initially