com.vividsolutions.jts.geomgraph.Depth Maven / Gradle / Ivy
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/*
* The JTS Topology Suite is a collection of Java classes that
* implement the fundamental operations required to validate a given
* geo-spatial data set to a known topological specification.
*
* Copyright (C) 2001 Vivid Solutions
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* For more information, contact:
*
* Vivid Solutions
* Suite #1A
* 2328 Government Street
* Victoria BC V8T 5G5
* Canada
*
* (250)385-6040
* www.vividsolutions.com
*/
package com.vividsolutions.jts.geomgraph;
import com.vividsolutions.jts.geomgraph.Position;
import com.vividsolutions.jts.geom.Location;
/**
* A Depth object records the topological depth of the sides
* of an Edge for up to two Geometries.
* @version 1.7
*/
public class Depth {
private final static int NULL_VALUE = -1;
public static int depthAtLocation(int location)
{
if (location == Location.EXTERIOR) return 0;
if (location == Location.INTERIOR) return 1;
return NULL_VALUE;
}
private int[][] depth = new int[2][3];
public Depth() {
// initialize depth array to a sentinel value
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 3; j++) {
depth[i][j] = NULL_VALUE;
}
}
}
public int getDepth(int geomIndex, int posIndex)
{
return depth[geomIndex][posIndex];
}
public void setDepth(int geomIndex, int posIndex, int depthValue)
{
depth[geomIndex][posIndex] = depthValue;
}
public int getLocation(int geomIndex, int posIndex)
{
if (depth[geomIndex][posIndex] <= 0) return Location.EXTERIOR;
return Location.INTERIOR;
}
public void add(int geomIndex, int posIndex, int location)
{
if (location == Location.INTERIOR)
depth[geomIndex][posIndex]++;
}
/**
* A Depth object is null (has never been initialized) if all depths are null.
*/
public boolean isNull()
{
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 3; j++) {
if (depth[i][j] != NULL_VALUE)
return false;
}
}
return true;
}
public boolean isNull(int geomIndex)
{
return depth[geomIndex][1] == NULL_VALUE;
}
public boolean isNull(int geomIndex, int posIndex)
{
return depth[geomIndex][posIndex] == NULL_VALUE;
}
public void add(Label lbl)
{
for (int i = 0; i < 2; i++) {
for (int j = 1; j < 3; j++) {
int loc = lbl.getLocation(i, j);
if (loc == Location.EXTERIOR || loc == Location.INTERIOR) {
// initialize depth if it is null, otherwise add this location value
if (isNull(i, j)) {
depth[i][j] = depthAtLocation(loc);
}
else
depth[i][j] += depthAtLocation(loc);
}
}
}
}
public int getDelta(int geomIndex)
{
return depth[geomIndex][Position.RIGHT] - depth[geomIndex][Position.LEFT];
}
/**
* Normalize the depths for each geometry, if they are non-null.
* A normalized depth
* has depth values in the set { 0, 1 }.
* Normalizing the depths
* involves reducing the depths by the same amount so that at least
* one of them is 0. If the remaining value is > 0, it is set to 1.
*/
public void normalize()
{
for (int i = 0; i < 2; i++) {
if (! isNull(i)) {
int minDepth = depth[i][1];
if (depth[i][2] < minDepth)
minDepth = depth[i][2];
if (minDepth < 0) minDepth = 0;
for (int j = 1; j < 3; j++) {
int newValue = 0;
if (depth[i][j] > minDepth)
newValue = 1;
depth[i][j] = newValue;
}
}
}
}
public String toString()
{
return
"A: " + depth[0][1] + "," + depth[0][2]
+ " B: " + depth[1][1] + "," + depth[1][2];
}
}