/* This program 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 3 of
the License, or (at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
package org.opentripplanner.analyst.request;
import java.util.ArrayList;
import java.util.List;
import org.opentripplanner.analyst.core.IsochroneData;
import org.opentripplanner.analyst.request.SampleGridRenderer.WTWD;
import org.opentripplanner.common.geometry.DelaunayIsolineBuilder;
import org.opentripplanner.common.geometry.IsolineBuilder.ZMetric;
import org.opentripplanner.common.geometry.ZSampleGrid;
import org.opentripplanner.routing.core.RoutingRequest;
import org.opentripplanner.routing.impl.SPTServiceFactory;
import org.opentripplanner.routing.services.GraphService;
import org.opentripplanner.routing.services.SPTService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Compute isochrones out of a shortest path tree request (AccSampling isoline algorithm).
*
* @author laurent
*/
public class IsoChroneSPTRendererAccSampling implements IsoChroneSPTRenderer {
private static final Logger LOG = LoggerFactory
.getLogger(IsoChroneSPTRendererAccSampling.class);
private GraphService graphService;
private SPTServiceFactory sptServiceFactory;
private SampleGridRenderer sampleGridRenderer;
public IsoChroneSPTRendererAccSampling(GraphService graphService, SPTServiceFactory sptServiceFactory, SampleGridRenderer sampleGridRenderer) {
this.graphService = graphService;
this.sptServiceFactory = sptServiceFactory;
this.sampleGridRenderer = sampleGridRenderer;
}
/**
* @param isoChroneRequest
* @param sptRequest
* @return
*/
@Override
public List<IsochroneData> getIsochrones(IsoChroneRequest isoChroneRequest,
RoutingRequest sptRequest) {
final double D0 = sampleGridRenderer.getOffRoadDistanceMeters(isoChroneRequest.precisionMeters);
// 1. Create a sample grid from the SPT, using the TimeGridRenderer
SampleGridRequest tgRequest = new SampleGridRequest();
tgRequest.maxTimeSec = isoChroneRequest.maxTimeSec;
tgRequest.precisionMeters = isoChroneRequest.precisionMeters;
tgRequest.coordinateOrigin = isoChroneRequest.coordinateOrigin;
ZSampleGrid<WTWD> sampleGrid = sampleGridRenderer.getSampleGrid(tgRequest, sptRequest);
// 2. Compute isolines
long t0 = System.currentTimeMillis();
ZMetric<WTWD> zMetric = new ZMetric<WTWD>() {
@Override
public int cut(WTWD zA, WTWD zB, WTWD z0) {
double t0 = z0.wTime / z0.w;
double tA = zA.d > z0.d ? Double.POSITIVE_INFINITY : zA.wTime / zA.w;
double tB = zB.d > z0.d ? Double.POSITIVE_INFINITY : zB.wTime / zB.w;
if (tA < t0 && t0 <= tB)
return 1;
if (tB < t0 && t0 <= tA)
return -1;
return 0;
}
@Override
public double interpolate(WTWD zA, WTWD zB, WTWD z0) {
if (zA.d > z0.d || zB.d > z0.d) {
if (zA.d > z0.d && zB.d > z0.d)
throw new AssertionError("dA > d0 && dB > d0");
// Interpolate on d
double k = zA.d == zB.d ? 0.5 : (z0.d - zA.d) / (zB.d - zA.d);
return k;
} else {
// Interpolate on t
double tA = zA.wTime / zA.w;
double tB = zB.wTime / zB.w;
double t0 = z0.wTime / z0.w;
double k = tA == tB ? 0.5 : (t0 - tA) / (tB - tA);
return k;
}
}
};
DelaunayIsolineBuilder<WTWD> isolineBuilder = new DelaunayIsolineBuilder<WTWD>(
sampleGrid.delaunayTriangulate(), zMetric);
isolineBuilder.setDebug(isoChroneRequest.includeDebugGeometry);
List<IsochroneData> isochrones = new ArrayList<IsochroneData>();
for (Integer cutoffSec : isoChroneRequest.cutoffSecList) {
WTWD z0 = new WTWD();
z0.w = 1.0;
z0.wTime = cutoffSec;
z0.d = D0;
IsochroneData isochrone = new IsochroneData(cutoffSec,
isolineBuilder.computeIsoline(z0));
if (isoChroneRequest.includeDebugGeometry)
isochrone.debugGeometry = isolineBuilder.getDebugGeometry();
isochrones.add(isochrone);
}
long t1 = System.currentTimeMillis();
LOG.info("Computed {} isochrones in {}msec", isochrones.size(), (int) (t1 - t0));
return isochrones;
}
}