Algorithm 751: TRIPACK: A constrained two-dimensional Delaunay triangulation package

TRIPACK is a Fortran 77 software package that employs an incremental algorithm to construct a constrained Delaunay triangulation of a set of points in the plane (nodes). The triangulation covers the convex hull of the nodes but may include polygonal constraint regions whose triangles are distinguishable from those in the remainder of the triangulation. This effectively allows for a nonconvex or multiply connected triangulation (the complement of the union of constraint regions) while retaining the efficiency of searching and updating a convex triangulation. The package provides a wide range of capabilities including an efficient means of updating the triangulation with nodal additions or deletions. For N nodes, the storage requirement is 13N integer storage locations in addition to the 2N nodal coordinates.