Namespace NetTopologySuite.Triangulate

Classes to compute Delaunay triangulations.

Classes

ConformingDelaunayTriangulationBuilder

A utility class which creates Conforming Delaunay Triangulations from collections of points and linear constraints, and extract the resulting triangulation edges or triangles as geometries.

ConformingDelaunayTriangulator

Computes a Conforming Delaunay Triangulation over a set of sites and a set of linear constraints.

ConstraintEnforcementException

Indicates a failure during constraint enforcement.

ConstraintVertex

A vertex in a Constrained Delaunay Triangulation. The vertex may or may not lie on a constraint. If it does it may carry extra information about the original constraint.

DelaunayTriangulationBuilder

A utility class which creates Delaunay Triangulations from collections of points and extract the resulting triangulation edges or triangles as geometries.

IncrementalDelaunayTriangulator

Computes a Delaunay Triangulation of a set of Vertexes, using an incremental insertion algorithm.

MidpointSplitPointFinder

A simple split point finder which returns the midpoint of the split segment. This is a default strategy only. Usually a more sophisticated strategy is required to prevent repeated splitting. Other points which could be used are:

• The projection of the encroaching point on the segment
• A point on the segment which will produce two segments which will not be further encroached
• The point on the segment which is the same distance from an endpoint as the encroaching
point

NonEncroachingSplitPointFinder

A strategy for finding constraint split points which attempts to maximise the length of the split segments while preventing further encroachment. (This is not always possible for narrow angles).

Segment

Models a constraint segment in a triangulation. A constraint segment is an oriented straight line segment between a start point and an end point.

SplitSegment

Models a constraint segment which can be split in two in various ways, according to certain geometric constraints.

VertexTaggedGeometryDataMapper

Creates a map between the vertex Coordinates of a set of Geometrys, and the parent geometry, and transfers the source geometry data objects to geometry components tagged with the coordinates.

VoronoiDiagramBuilder

A utility class which creates Voronoi Diagrams from collections of points. The diagram is returned as a GeometryCollection of NetTopologySuite.Triangulate.Polygons, representing the faces of the Voronoi diagram. /// The faces are clipped to the larger of:

• an envelope supplied by ClipEnvelope.set.
• an envelope determined by the input sites.

The userData attribute of each face Polygon is set to the Coordinate of the corresponding input site. This allows using a Map to link faces to data associated with sites.

Interfaces

ConstraintVertexFactory

An interface for factories which create a ConstraintVertex

IConstraintSplitPointFinder

An interface for strategies for determining the location of split points on constraint segments. The location of split points has a large effect on the performance and robustness of enforcing a constrained Delaunay triangulation. Poorly chosen split points can cause repeated splitting, especially at narrow constraint angles, since the split point will end up encroaching on the segment containing the original encroaching point. With detailed knowledge of the geometry of the constraints, it is sometimes possible to choose better locations for splitting.