An algorithm to searching for the kernel of a simple polygon

In this paper, an algorithm to searching for the kernel of a simple polygon is proposed. The concave vertices of the polygon are merely deal with in the course of finding the kernel so the algorithm is efficient. The kernel of a polygon is found by cutting the polygon region using the lines passing by the edge which adjacent a concave vertex. In this course, a method is presented to determinate whether a ray intersect with a line segment by two special triangles´ orientations which are identified by extremity vertices sequence. Not only can the algorithm judge whether the kernel of simple polygon is empty timely, but also get the vertexes of boundaries of the kernel. Test results show the high efficiency and stability of this algorithm.