maspack.geometry

Class DelaunayTriangulator

java.lang.Object

maspack.geometry.DelaunayTriangulator

public class DelaunayTriangulator
extends java.lang.Object

Computes Delaunay and constrained Delaunay triangulations. It uses the utility Poly2Tri, available from https://github.com/orbisgis/poly2tri.java and released under the following BSD 3-Clause license:

Copyright (c) 2015, Poly2Tri Contributors. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
3. Neither the name of Poly2Tri nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DelaunayTriangulator.Triangle Returns information about a specific Delaunay triangle.

Constructor Summary

Constructors

Constructor and Description
DelaunayTriangulator()

Method Summary

Modifier and Type	Method and Description
static PolygonalMesh	createMesh(java.util.List<? extends Vector2d> points) Creates a PolygonalMesh, in the x-y plane, from the Delaunay triangulation of a set of 2D points.
static PolygonalMesh	createMesh(java.util.List<? extends Vector2d> points, int[] constraints) Creates a PolygonalMesh, in the x-y plane, from the constrained Delaunay triangulation of a set of 2D points.
static void	main(java.lang.String[] args)
static java.util.List<DelaunayTriangulator.Triangle>	triangulate(java.util.List<? extends Vector2d> points) Computes the Delaunay triangulation of a set of 2D points.
static java.util.List<DelaunayTriangulator.Triangle>	triangulate(java.util.List<? extends Vector2d> points, int[] constraints) Computes the constrained Delaunay triangulation of a set of 2D points.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DelaunayTriangulator

public DelaunayTriangulator()

Method Detail

triangulate

public static java.util.List<DelaunayTriangulator.Triangle> triangulate(java.util.List<? extends Vector2d> points)

Computes the Delaunay triangulation of a set of 2D points. The triangles are returned as a list of DelaunayTriangulator.Triangle structures.

As indicated in the documentation for Poly2Tri, points should be unique within machine precision.

Parameters:

points - points to compute the triangulation for

Returns:

list of triangles

triangulate

public static java.util.List<DelaunayTriangulator.Triangle> triangulate(java.util.List<? extends Vector2d> points,
                                                                        int[] constraints)

Computes the constrained Delaunay triangulation of a set of 2D points. The constraints are indicated as an array of point indices defining the constraint edges. If there are numc constraints, then this array should have a length of 2*numc, with two point indices per constraint. The triangles are returned as a list of DelaunayTriangulator.Triangle structures.

As indicated in the documentation for Poly2Tri, points should be unique within machine precision, and no check is made to ensure that the constraints constitute a valid constraint set (e.g., no check is made to ensure that constraint edges do not cross eah other).

Parameters:

points - points to compute the triangulation for

constraints - if non-null, specifices indices of the points defining the constrained edges

Returns:

list of triangles

createMesh

public static PolygonalMesh createMesh(java.util.List<? extends Vector2d> points)

Creates a PolygonalMesh, in the x-y plane, from the Delaunay triangulation of a set of 2D points.

As indicated in the documentation for Poly2Tri, points should be unique within machine precision.

Parameters:

points - points to compute the triangulation for

Returns:

mesh created from the triangulation

createMesh

public static PolygonalMesh createMesh(java.util.List<? extends Vector2d> points,
                                       int[] constraints)

Creates a PolygonalMesh, in the x-y plane, from the constrained Delaunay triangulation of a set of 2D points. The constraints are indicated as an array of point indices defining the constraint edges. If there are numc constraints, then this array should have a length of 2*numc, with two point indices per constraint.

As indicated in the documentation for Poly2Tri, points should be unique within machine precision, and no check is made to ensure that the constraints constitute a valid constraint set (e.g., no check is made to ensure that constraint edges do not cross eah other).

Parameters:

points - points to compute the triangulation for

constraints - if non-null, specifices indices of the points defining the constrained edges

Returns:

mesh created from the triangulation

main

public static void main(java.lang.String[] args)