/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, Open Source Geospatial Foundation (OSGeo)
*
* 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;
* version 2.1 of the License.
*
* 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.
*/
package org.geotools.renderer.crs;
import java.util.ArrayList;
import java.util.List;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.referencing.CRS;
import org.geotools.referencing.crs.DefaultGeographicCRS;
import org.geotools.referencing.operation.projection.MapProjection;
import org.geotools.referencing.operation.projection.MapProjection.AbstractProvider;
import org.geotools.referencing.operation.projection.PolarStereographic;
import org.geotools.referencing.operation.projection.TransverseMercator;
import org.opengis.parameter.ParameterNotFoundException;
import org.opengis.parameter.ParameterValue;
import org.opengis.referencing.FactoryException;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
import org.opengis.referencing.operation.TransformException;
/**
* Returns a {@link ProjectionHandler} for the {@link TransverseMercator} projection
* that will cut geometries 45° away from the projection central meridian
*
* @author Andrea Aime - OpenGeo
*
*
* @source $URL$
*/
public class PolarStereographicHandlerFactory implements ProjectionHandlerFactory {
public ProjectionHandler getHandler(ReferencedEnvelope renderingEnvelope, CoordinateReferenceSystem sourceCrs, boolean wrap, int maxWraps) throws FactoryException {
MapProjection mapProjection = CRS.getMapProjection(renderingEnvelope
.getCoordinateReferenceSystem());
if (renderingEnvelope != null && mapProjection instanceof PolarStereographic) {
boolean north;
// variant B uses standard_parallel
ParameterValue<?> stdParallel = null;
try {
stdParallel = mapProjection.getParameterValues().parameter(
AbstractProvider.STANDARD_PARALLEL_1.getName().getCode());
} catch (ParameterNotFoundException e) {
// ignore
}
if(stdParallel != null) {
north = stdParallel.doubleValue() > 0;
} else {
// variant A uses latitude of origin
ParameterValue<?> latOrigin = null;
try {
latOrigin = mapProjection.getParameterValues().parameter(
AbstractProvider.LATITUDE_OF_ORIGIN.getName().getCode());
} catch (ParameterNotFoundException e) {
// ignore
}
if(latOrigin != null) {
north = latOrigin.doubleValue() > 0;
} else {
return null;
}
}
ReferencedEnvelope validArea;
if(north) {
validArea = new ReferencedEnvelope(-Double.MAX_VALUE, Double.MAX_VALUE, -0, 90, DefaultGeographicCRS.WGS84);
} else {
validArea = new ReferencedEnvelope(-Double.MAX_VALUE, Double.MAX_VALUE, -90, 0, DefaultGeographicCRS.WGS84);
}
return new ProjectionHandler(sourceCrs, validArea, renderingEnvelope) {
@Override
public List<ReferencedEnvelope> getQueryEnvelopes() throws TransformException,
FactoryException {
// check if we are crossing the antimeridian and are fully below the pole,
// in this case we'd end up reading the full globe when we'd have to just
// read two portions near the dateline
if (renderingEnvelope.getMaxY() < 0 && renderingEnvelope.getMinX() < 0
&& renderingEnvelope.getMaxX() > 0) {
ReferencedEnvelope e1 = new ReferencedEnvelope(renderingEnvelope.getMinX(),
-1e-6, renderingEnvelope.getMinY(), renderingEnvelope.getMaxY(),
renderingEnvelope.getCoordinateReferenceSystem());
ReferencedEnvelope e2 = new ReferencedEnvelope(1e-6,
renderingEnvelope.getMaxX(), renderingEnvelope.getMinY(),
renderingEnvelope.getMaxY(),
renderingEnvelope.getCoordinateReferenceSystem());
List<ReferencedEnvelope> envelopes = new ArrayList<ReferencedEnvelope>();
envelopes.add(e1);
envelopes.add(e2);
reprojectEnvelopes(sourceCRS, envelopes);
return envelopes;
} else {
return super.getQueryEnvelopes();
}
}
};
}
return null;
}
}