Class TaggedLineString

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
13	package org.locationtech.jts.simplify;
14
15	import java.util.ArrayList;
16	import java.util.List;
17
18	import org.locationtech.jts.geom.Coordinate;
19	import org.locationtech.jts.geom.LineSegment;
20	import org.locationtech.jts.geom.LineString;
21	import org.locationtech.jts.geom.LinearRing;
22
23	/**
24	* Represents a {@link LineString} which can be modified to a simplified shape.
25	* This class provides an attribute which specifies the minimum allowable length
26	* for the modified result.
27	*
28	* @version 1.7
29	*/
30	class TaggedLineString
31	{
32
33	private LineString parentLine;
34	private TaggedLineSegment[] segs;
35	private List resultSegs = new ArrayList();
36	private int minimumSize;
37
38	public TaggedLineString(LineString parentLine) {
39	this(parentLine, 2);
40	}
41
42	public TaggedLineString(LineString parentLine, int minimumSize) {
43	this.parentLine = parentLine;
44	this.minimumSize = minimumSize;
45	init();
46	}
47
48	public int getMinimumSize() { return minimumSize; }
49	public LineString getParent() { return parentLine; }
50	public Coordinate[] getParentCoordinates() { return parentLine.getCoordinates(); }
51	public Coordinate[] getResultCoordinates() { return extractCoordinates(resultSegs); }
52
53	public int getResultSize()
54	{
55	int resultSegsSize = resultSegs.size();
56	return resultSegsSize == 0 ? 0 : resultSegsSize + 1;
57	}
58
59	public TaggedLineSegment getSegment(int i) { return segs[i]; }
60
61	private void init()
62	{
63	Coordinate[] pts = parentLine.getCoordinates();
64	segs = new TaggedLineSegment[pts.length - 1];
65	for (int i = 0; i < pts.length - 1; i++) {
66	TaggedLineSegment seg
67	= new TaggedLineSegment(pts[i], pts[i + 1], parentLine, i);
68	segs[i] = seg;
69	}
70	}
71
72	public TaggedLineSegment[] getSegments() { return segs; }
73
74	public void addToResult(LineSegment seg)
75	{
76	resultSegs.add(seg);
77	}
78
79	public LineString asLineString()
80	{
81	return parentLine.getFactory().createLineString(extractCoordinates(resultSegs));
82	}
83
84	public LinearRing asLinearRing() {
85	return parentLine.getFactory().createLinearRing(extractCoordinates(resultSegs));
86	}
87
88	private static Coordinate[] extractCoordinates(List segs)
89	{
90	Coordinate[] pts = new Coordinate[segs.size() + 1];
91	LineSegment seg = null;
92	for (int i = 0; i < segs.size(); i++) {
93	seg = (LineSegment) segs.get(i);
94	pts[i] = seg.p0;
95	}
96	// add last point
97	pts[pts.length - 1] = seg.p1;
98	return pts;
99	}
100
101
102	}
103