Delaunay and constrained Delaunay triangulations implementation of a dynamic Delaunay triangulation algorithm. The functions described in this section are useful to build two-dimensional Delaunay and constrained Delaunay triangulations. Only the @x and @y coordinates of the points are taken into account. The algorithm is fully dynamic (insertion and deletion) for Delaunay triangulation and semi-dynamic (insertion only of vertices and constraints) for constrained Delaunay triangulation. The insertion part uses a very simple jump-and-walk location algorithm which can be used on any (even non-Delaunay) 2D triangulation as long as its boundary is convex. The functions gts_delaunay_conform() and gts_delaunay_refine() can be used to build Delaunay conforming constrained triangulations and to refine them. @klass: @obj: @obj: @Returns: @p: @surface: @guess: @Returns: @surface: @v: @guess: @Returns: @surface: @v: @f: @Returns: @surface: @v: @surface: @c: @Returns: @surface: @Returns: @surface: @surface: @steiner_max: @encroaches: @data: @Returns: @surface: @steiner_max: @encroaches: @encroach_data: @cost: @cost_data: @Returns: