/*
* Copyright (c) 2016 Martin Davis.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
*
* http://www.eclipse.org/org/documents/edl-v10.php.
*/
package org.locationtech.jts.precision;
import org.locationtech.jts.geom.Coordinate;
import org.locationtech.jts.geom.CoordinateList;
import org.locationtech.jts.geom.Geometry;
import org.locationtech.jts.geom.LineString;
import org.locationtech.jts.geom.LinearRing;
import org.locationtech.jts.geom.PrecisionModel;
import org.locationtech.jts.geom.util.GeometryEditor;
public class PrecisionReducerCoordinateOperation extends
GeometryEditor.CoordinateOperation
{
private PrecisionModel targetPM;
private boolean removeCollapsed = true;
public PrecisionReducerCoordinateOperation(PrecisionModel targetPM, boolean removeCollapsed)
{
this.targetPM = targetPM;
this.removeCollapsed = removeCollapsed;
}
public Coordinate[] edit(Coordinate[] coordinates, Geometry geom) {
if (coordinates.length == 0)
return null;
Coordinate[] reducedCoords = new Coordinate[coordinates.length];
// copy coordinates and reduce
for (int i = 0; i < coordinates.length; i++) {
Coordinate coord = new Coordinate(coordinates[i]);
targetPM.makePrecise(coord);
reducedCoords[i] = coord;
}
// remove repeated points, to simplify returned geometry as much as possible
CoordinateList noRepeatedCoordList = new CoordinateList(reducedCoords,
false);
Coordinate[] noRepeatedCoords = noRepeatedCoordList.toCoordinateArray();
/**
* Check to see if the removal of repeated points collapsed the coordinate
* List to an invalid length for the type of the parent geometry. It is not
* necessary to check for Point collapses, since the coordinate list can
* never collapse to less than one point. If the length is invalid, return
* the full-length coordinate array first computed, or null if collapses are
* being removed. (This may create an invalid geometry - the client must
* handle this.)
*/
int minLength = 0;
if (geom instanceof LineString)
minLength = 2;
if (geom instanceof LinearRing)
minLength = 4;
Coordinate[] collapsedCoords = reducedCoords;
if (removeCollapsed)
collapsedCoords = null;
// return null or orginal length coordinate array
if (noRepeatedCoords.length < minLength) {
return collapsedCoords;
}
// ok to return shorter coordinate array
return noRepeatedCoords;
}
}