Class ShapeCollectionPathIterator

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.awt;
13
14	import java.awt.Shape;
15	import java.awt.geom.AffineTransform;
16	import java.awt.geom.PathIterator;
17	import java.util.Collection;
18	import java.util.Iterator;
19
20	/**
21	* A {@link PathIterator} which provides paths for a collection of {@link Shape}s.
22	*
23	* @author Martin Davis
24	*/
25	public class ShapeCollectionPathIterator implements PathIterator {
26	private Iterator shapeIterator;
27
28	// initialize with a no-op iterator
29	private PathIterator currentPathIterator = new PathIterator() {
30	public int getWindingRule() {
31	throw new UnsupportedOperationException();
32	}
33
34	public boolean isDone() {
35	return true;
36	}
37
38	public void next() {
39	}
40
41	public int currentSegment(float[] coords) {
42	throw new UnsupportedOperationException();
43	}
44
45	public int currentSegment(double[] coords) {
46	throw new UnsupportedOperationException();
47	}
48	};
49
50	private AffineTransform affineTransform;
51	private boolean done = false;
52
53	/**
54	* Creates a new path iterator for a collection of {@link Shape}s.
55	*
56	* @param shapes the Shapes in the collection
57	* @param affineTransform a optional transformation to be applied to the coordinates in the path (may be null)
58	*/
59	public ShapeCollectionPathIterator(Collection shapes,
60	AffineTransform affineTransform) {
61	shapeIterator = shapes.iterator();
62	this.affineTransform = affineTransform;
63	next();
64	}
65
66	public int getWindingRule() {
67	/**
68	* WIND_NON_ZERO is more accurate than WIND_EVEN_ODD, and can be comparable
69	* in speed. (See http://www.geometryalgorithms.com/Archive/algorithm_0103/algorithm_0103.htm#Winding%20Number)
70	* However, WIND_NON_ZERO requires that the
71	* shell and holes be oriented in a certain way.
72	* So use WIND_EVEN_ODD.
73	*/
74	return PathIterator.WIND_EVEN_ODD;
75	}
76
77	public boolean isDone() {
78	return done;
79	}
80
81	public void next() {
82	currentPathIterator.next();
83
84	if (currentPathIterator.isDone() && !shapeIterator.hasNext()) {
85	done = true;
86	return;
87	}
88	if (currentPathIterator.isDone()) {
89	currentPathIterator = ((Shape) shapeIterator.next()).getPathIterator(affineTransform);
90	}
91	}
92
93	public int currentSegment(float[] coords) {
94	return currentPathIterator.currentSegment(coords);
95	}
96
97	public int currentSegment(double[] coords) {
98	return currentPathIterator.currentSegment(coords);
99	}
100	}
101