Class Depth

1
2
3	/*
4	* Copyright (c) 2016 Vivid Solutions.
5	*
6	* All rights reserved. This program and the accompanying materials
7	* are made available under the terms of the Eclipse Public License 2.0
8	* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
9	* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
10	* and the Eclipse Distribution License is available at
11	*
12	* http://www.eclipse.org/org/documents/edl-v10.php.
13	*/
14	package org.locationtech.jts.geomgraph;
15
16	import org.locationtech.jts.geom.Location;
17
18	/**
19	* A Depth object records the topological depth of the sides
20	* of an Edge for up to two Geometries.
21	* @version 1.7
22	*/
23	public class Depth {
24
25	private final static int NULL_VALUE = -1;
26
27	public static int depthAtLocation(int location)
28	{
29	if (location == Location.EXTERIOR) return 0;
30	if (location == Location.INTERIOR) return 1;
31	return NULL_VALUE;
32	}
33
34	private int[][] depth = new int[2][3];
35
36	public Depth() {
37	// initialize depth array to a sentinel value
38	for (int i = 0; i < 2; i++) {
39	for (int j = 0; j < 3; j++) {
40	depth[i][j] = NULL_VALUE;
41	}
42	}
43	}
44
45	public int getDepth(int geomIndex, int posIndex)
46	{
47	return depth[geomIndex][posIndex];
48	}
49	public void setDepth(int geomIndex, int posIndex, int depthValue)
50	{
51	depth[geomIndex][posIndex] = depthValue;
52	}
53	public int getLocation(int geomIndex, int posIndex)
54	{
55	if (depth[geomIndex][posIndex] <= 0) return Location.EXTERIOR;
56	return Location.INTERIOR;
57	}
58	public void add(int geomIndex, int posIndex, int location)
59	{
60	if (location == Location.INTERIOR)
61	depth[geomIndex][posIndex]++;
62	}
63	/**
64	* A Depth object is null (has never been initialized) if all depths are null.
65	*/
66	public boolean isNull()
67	{
68	for (int i = 0; i < 2; i++) {
69	for (int j = 0; j < 3; j++) {
70	if (depth[i][j] != NULL_VALUE)
71	return false;
72	}
73	}
74	return true;
75	}
76	public boolean isNull(int geomIndex)
77	{
78	return depth[geomIndex][1] == NULL_VALUE;
79	}
80	public boolean isNull(int geomIndex, int posIndex)
81	{
82	return depth[geomIndex][posIndex] == NULL_VALUE;
83	}
84	public void add(Label lbl)
85	{
86	for (int i = 0; i < 2; i++) {
87	for (int j = 1; j < 3; j++) {
88	int loc = lbl.getLocation(i, j);
89	if (loc == Location.EXTERIOR \|\| loc == Location.INTERIOR) {
90	// initialize depth if it is null, otherwise add this location value
91	if (isNull(i, j)) {
92	depth[i][j] = depthAtLocation(loc);
93	}
94	else
95	depth[i][j] += depthAtLocation(loc);
96	}
97	}
98	}
99	}
100	public int getDelta(int geomIndex)
101	{
102	return depth[geomIndex][Position.RIGHT] - depth[geomIndex][Position.LEFT];
103	}
104	/**
105	* Normalize the depths for each geometry, if they are non-null.
106	* A normalized depth
107	* has depth values in the set { 0, 1 }.
108	* Normalizing the depths
109	* involves reducing the depths by the same amount so that at least
110	* one of them is 0. If the remaining value is > 0, it is set to 1.
111	*/
112	public void normalize()
113	{
114	for (int i = 0; i < 2; i++) {
115	if (! isNull(i)) {
116	int minDepth = depth[i][1];
117	if (depth[i][2] < minDepth)
118	minDepth = depth[i][2];
119
120	if (minDepth < 0) minDepth = 0;
121	for (int j = 1; j < 3; j++) {
122	int newValue = 0;
123	if (depth[i][j] > minDepth)
124	newValue = 1;
125	depth[i][j] = newValue;
126	}
127	}
128	}
129	}
130
131	public String toString()
132	{
133	return
134	"A: " + depth[0][1] + "," + depth[0][2]
135	+ " B: " + depth[1][1] + "," + depth[1][2];
136	}
137	}
138