Class MarkHalfEdge

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.edgegraph;
14
15	import org.locationtech.jts.geom.Coordinate;
16
17	/**
18	* A {@link HalfEdge} which supports
19	* marking edges with a boolean flag.
20	* Useful for algorithms which perform graph traversals.
21	*
22	* @author Martin Davis
23	*
24	*/
25	public class MarkHalfEdge extends HalfEdge
26	{
27	/**
28	* Tests whether the given edge is marked.
29	*
30	* @param e the edge to test
31	* @return true if the edge is marked
32	*/
33	public static boolean isMarked(HalfEdge e)
34	{
35	return ((MarkHalfEdge) e).isMarked();
36	}
37
38	/**
39	* Marks the given edge.
40	*
41	* @param e the edge to mark
42	*/
43	public static void mark(HalfEdge e)
44	{
45	((MarkHalfEdge) e).mark();
46	}
47
48	/**
49	* Sets the mark for the given edge to a boolean value.
50	*
51	* @param e the edge to set
52	* @param isMarked the mark value
53	*/
54	public static void setMark(HalfEdge e, boolean isMarked)
55	{
56	((MarkHalfEdge) e).setMark(isMarked);
57	}
58
59	/**
60	* Sets the mark for the given edge pair to a boolean value.
61	*
62	* @param e an edge of the pair to update
63	* @param isMarked the mark value to set
64	*/
65	public static void setMarkBoth(HalfEdge e, boolean isMarked)
66	{
67	((MarkHalfEdge) e).setMark(isMarked);
68	((MarkHalfEdge) e.sym()).setMark(isMarked);
69	}
70
71	/**
72	* Marks the edges in a pair.
73	*
74	* @param e an edge of the pair to mark
75	*/
76	public static void markBoth(HalfEdge e) {
77	((MarkHalfEdge) e).mark();
78	((MarkHalfEdge) e.sym()).mark();
79	}
80
81	private boolean isMarked = false;
82
83	/**
84	* Creates a new marked edge.
85	*
86	* @param orig the coordinate of the edge origin
87	*/
88	public MarkHalfEdge(Coordinate orig) {
89	super(orig);
90	}
91
92	/**
93	* Tests whether this edge is marked.
94	*
95	* @return true if this edge is marked
96	*/
97	public boolean isMarked()
98	{
99	return isMarked ;
100	}
101
102	/**
103	* Marks this edge.
104	*
105	*/
106	public void mark()
107	{
108	isMarked = true;
109	}
110
111	/**
112	* Sets the value of the mark on this edge.
113	*
114	* @param isMarked the mark value to set
115	*/
116	public void setMark(boolean isMarked)
117	{
118	this.isMarked = isMarked;
119	}
120
121
122	}
123