/*
* This is part of Geomajas, a GIS framework, http://www.geomajas.org/.
*
* Copyright 2008-2011 Geosparc nv, http://www.geosparc.com/, Belgium.
*
* The program is available in open source according to the GNU Affero
* General Public License. All contributions in this program are covered
* by the Geomajas Contributors License Agreement. For full licensing
* details, see LICENSE.txt in the project root.
*/
package org.geomajas.widget.searchandfilter.command.searchandfilter;
import java.util.ArrayList;
import java.util.List;
import org.geomajas.command.Command;
import org.geomajas.service.DtoConverterService;
import org.geomajas.widget.searchandfilter.command.dto.GeometryUtilsRequest;
import org.geomajas.widget.searchandfilter.command.dto.GeometryUtilsResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import com.vividsolutions.jts.geom.Geometry;
/**
* Command to help with common geometry manipulations.
* <p>
* Manipulations throw as little exceptions as possible, eg. if you give null
* you get null returned, if you do not set an action, features are returned
* as-is.
* <p>Warning: Merge is not 100% exact, so do not use if area-size is important.
* @author Kristof Heirwegh
*/
@Component
public class GeometryUtilsCommand implements Command<GeometryUtilsRequest, GeometryUtilsResponse> {
private final Logger log = LoggerFactory.getLogger(GeometryUtilsCommand.class);
@Autowired
private DtoConverterService converter;
public void execute(final GeometryUtilsRequest request, final GeometryUtilsResponse response) throws Exception {
if (request.getGeometries() != null && request.getGeometries().length > 0) {
int geomCount = request.getGeometries().length;
log.debug("GeometryUtilsCommand for " + geomCount + " geometries.");
if (request.getActionFlags() == 0) {
response.setGeometries(request.getGeometries());
}
// convert to internal
Geometry[] lastResult = new Geometry[geomCount];
org.geomajas.geometry.Geometry[] dtoGeoms = request.getGeometries();
for (int i = 0; i < geomCount; i++) {
lastResult[i] = converter.toInternal(dtoGeoms[i]);
}
List<Geometry[]> intermediateResults = new ArrayList<Geometry[]>();
// do merge before buffer
if ((request.getActionFlags() & GeometryUtilsRequest.ACTION_MERGE) > 0) {
lastResult = merge(lastResult);
intermediateResults.add(lastResult);
}
if ((request.getActionFlags() & GeometryUtilsRequest.ACTION_BUFFER) > 0) {
lastResult = buffer(lastResult, request.getBuffer(), request.getBufferQuadrantSegments());
intermediateResults.add(lastResult);
}
// -- other actions here
// ----------------------------------------------------------
List<org.geomajas.geometry.Geometry> dtoResult = new ArrayList<org.geomajas.geometry.Geometry>();
if (request.isIntermediateResults()) {
for (Geometry[] geometries : intermediateResults) {
for (Geometry geometry : geometries) {
dtoResult.add(converter.toDto(geometry));
}
}
} else {
for (Geometry geometry : lastResult) {
dtoResult.add(converter.toDto(geometry));
}
}
response.setGeometries(dtoResult.toArray(new org.geomajas.geometry.Geometry[dtoResult.size()]));
}
}
private Geometry[] buffer(Geometry[] geoms, double distance, int quadrants) {
Geometry[] result = new Geometry[geoms.length];
for (int i = 0; i < geoms.length; i++) {
result[i] = geoms[0].buffer(distance, quadrants);
}
return result;
}
private Geometry[] merge(Geometry[] geoms) {
Geometry[] result = new Geometry[1];
// points/lines to polygon, prevents problems later on...
// TODO this works for meters (1 cm) what with other crs's ?
Geometry merged = geoms[0].buffer(0.01);
for (int i = 1; i < geoms.length; i++) {
merged = merged.union(geoms[i].buffer(0.01));
}
result[0] = merged;
return result;
}
public GeometryUtilsResponse getEmptyCommandResponse() {
return new GeometryUtilsResponse();
}
}