Class InteriorPointPoint

1
2	/*
3	* Copyright (c) 2016 Vivid Solutions.
4	*
5	* All rights reserved. This program and the accompanying materials
6	* are made available under the terms of the Eclipse Public License 2.0
7	* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
8	* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
9	* and the Eclipse Distribution License is available at
10	*
11	* http://www.eclipse.org/org/documents/edl-v10.php.
12	*/
13	package org.locationtech.jts.algorithm;
14
15	import org.locationtech.jts.geom.Coordinate;
16	import org.locationtech.jts.geom.Geometry;
17	import org.locationtech.jts.geom.GeometryCollection;
18	import org.locationtech.jts.geom.Point;
19
20	/**
21	* Computes a point in the interior of an point geometry.
22	* <h2>Algorithm</h2>
23	* Find a point which is closest to the centroid of the geometry.
24	*
25	* @version 1.7
26	*/
27	public class InteriorPointPoint {
28
29	/**
30	* Computes an interior point for the
31	* puntal components of a Geometry.
32	*
33	* @param geom the geometry to compute
34	* @return the computed interior point,
35	* or <code>null</code> if the geometry has no puntal components
36	*/
37	public static Coordinate getInteriorPoint(Geometry geom) {
38	InteriorPointPoint intPt = new InteriorPointPoint(geom);
39	return intPt.getInteriorPoint();
40	}
41
42	private Coordinate centroid;
43	private double minDistance = Double.MAX_VALUE;
44
45	private Coordinate interiorPoint = null;
46
47	public InteriorPointPoint(Geometry g)
48	{
49	centroid = g.getCentroid().getCoordinate();
50	add(g);
51	}
52
53	/**
54	* Tests the point(s) defined by a Geometry for the best inside point.
55	* If a Geometry is not of dimension 0 it is not tested.
56	* @param geom the geometry to add
57	*/
58	private void add(Geometry geom)
59	{
60	if (geom instanceof Point) {
61	add(geom.getCoordinate());
62	}
63	else if (geom instanceof GeometryCollection) {
64	GeometryCollection gc = (GeometryCollection) geom;
65	for (int i = 0; i < gc.getNumGeometries(); i++) {
66	add(gc.getGeometryN(i));
67	}
68	}
69	}
70	private void add(Coordinate point)
71	{
72	double dist = point.distance(centroid);
73	if (dist < minDistance) {
74	interiorPoint = new Coordinate(point);
75	minDistance = dist;
76	}
77	}
78
79	public Coordinate getInteriorPoint()
80	{
81	return interiorPoint;
82	}
83	}
84