Determining if a point is in a polygon or not is used by a lot of
applications in computer graphics, computer games and geoinformatics.
Implementing this check is error-prone since there are many special cases to be
considered. This holds true in particular for complex polygons whose edges
intersect each other creating holes. In this paper we present a simple even-odd
algorithm to solve this problem for complex polygons in linear time and prove
its correctness for all possible points and polygons. We furthermore provide
examples and implementation notes for this algorithm.Comment: Proceedings of the 12th International Joint Conference on Computer
Vision, Imaging and Computer Graphics Theory and Applications (VISIGRAPP
2017), Volume 1: GRAP
