Class PreparedLineString

1	/*
2	* Copyright (c) 2016 Vivid Solutions.
3	*
4	* All rights reserved. This program and the accompanying materials
5	* are made available under the terms of the Eclipse Public License 2.0
6	* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
7	* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
8	* and the Eclipse Distribution License is available at
9	*
10	* http://www.eclipse.org/org/documents/edl-v10.php.
11	*/
12	package org.locationtech.jts.geom.prep;
13
14	import org.locationtech.jts.geom.Geometry;
15	import org.locationtech.jts.geom.Lineal;
16	import org.locationtech.jts.noding.FastSegmentSetIntersectionFinder;
17	import org.locationtech.jts.noding.SegmentStringUtil;
18
19	/**
20	* A prepared version for {@link Lineal} geometries.
21	* <p>
22	* Instances of this class are thread-safe.
23	*
24	* @author mbdavis
25	*
26	*/
27	public class PreparedLineString
28	extends BasicPreparedGeometry
29	{
30	private FastSegmentSetIntersectionFinder segIntFinder = null;
31
32	public PreparedLineString(Lineal line) {
33	super((Geometry) line);
34	}
35
36	public synchronized FastSegmentSetIntersectionFinder getIntersectionFinder()
37	{
38	/**
39	* MD - Another option would be to use a simple scan for
40	* segment testing for small geometries.
41	* However, testing indicates that there is no particular advantage
42	* to this approach.
43	*/
44	if (segIntFinder == null)
45	segIntFinder = new FastSegmentSetIntersectionFinder(SegmentStringUtil.extractSegmentStrings(getGeometry()));
46	return segIntFinder;
47	}
48
49	public boolean intersects(Geometry g)
50	{
51	if (! envelopesIntersect(g)) return false;
52	return PreparedLineStringIntersects.intersects(this, g);
53	}
54
55	/**
56	* There's not much point in trying to optimize contains, since
57	* contains for linear targets requires the entire test geometry
58	* to exactly match the target linework.
59	*/
60	}
61