Namespace NetTopologySuite.Triangulate.Polygon

Classes for triangulating polygons. ConstrainedDelaunayTriangulator can be used to provide high-quality near-Delaunay triangulations of polygonal geometry. The PolygonTriangulator produces lower-quality but faster triangulations.

Classes

ConstrainedDelaunayTriangulator

Computes the Constrained Delaunay Triangulation of polygons. The Constrained Delaunay Triangulation of a polygon is a set of triangles covering the polygon, with the maximum total interior angle over all possible triangulations. It provides the "best quality" triangulation of the polygon.

Holes are supported.

PolygonHoleJoiner

Transforms a polygon with holes into a single self-touching (invalid) ring by joining holes to the exterior shell or to another hole with out-and-back line segments. The holes are added in order of their envelopes (leftmost/lowest first). As the result shell develops, a hole may be added to what was originally another hole.

There is no attempt to optimize the quality of the join lines. In particular, holes may be joined by lines longer than is optimal. However, holes which touch the shell or other holes are joined at the touch point.

The class does not require the input polygon to have normal orientation (shell CW and rings CCW). The output ring is always CW.

PolygonTriangulator

Computes a triangulation of each polygon in a {@link Geometry}. A polygon triangulation is a non-overlapping set of triangles which cover the polygon and have the same vertices as the polygon. The priority is on performance rather than triangulation quality, so that the output may contain many narrow triangles.

Holes are handled by joining them to the shell to form a (self-touching) polygon shell with no holes. Although invalid, this can be triangulated effectively.

For better-quality triangulation use ConstrainedDelaunayTriangulator.