/*
* 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.precision;
import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.CoordinateList;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.geom.LinearRing;
import com.vividsolutions.jts.geom.PrecisionModel;
import com.vividsolutions.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;
}
}