HeadwayGTUReal.java

package org.opentrafficsim.road.gtu.lane.perception.headway;

import org.djunits.value.vdouble.scalar.Length;
import org.opentrafficsim.core.gtu.GTUException;
import org.opentrafficsim.core.gtu.behavioralcharacteristics.BehavioralCharacteristics;
import org.opentrafficsim.core.network.NetworkException;
import org.opentrafficsim.road.gtu.lane.LaneBasedGTU;
import org.opentrafficsim.road.gtu.lane.tactical.following.CarFollowingModel;
import org.opentrafficsim.road.network.speed.SpeedLimitInfo;
import org.opentrafficsim.road.network.speed.SpeedLimitProspect;
import org.opentrafficsim.road.network.speed.SpeedLimitTypes;

/**
 * Container for a reference to information about a (lane based) GTU and a headway. The Headway can store information about GTUs
 * or objects ahead of the reference GTU, behind the reference GTU, or (partially) parallel to the reference GTU. In addition to
 * the (perceived) headway, several other pieces of information can be stored, such as (perceived) speed, (perceived)
 * acceleration, (perceived) turn indicators, and (perceived) braking lights. <br>
 * This particular version returns behavioral information about the observed GTU objects based on their real state.<br>
 * Special care must be taken in curves when perceiving headway of a GTU or object on an adjacent lane.The question is whether
 * we perceive the parallel or ahead/behind based on a line perpendicular to the front/back of the GTU (rectangular), or
 * perpendicular to the center line of the lane (wedge-shaped in case of a curve). The difficulty of a wedge-shaped situation is
 * that reciprocity might be violated: in case of a clothoid, for instance, it is not sure that the point on the center line
 * when projected from lane 1 to lane 2 is the same as the projection from lane 2 to lane 1. The same holds for shapes with
 * sharp bends. Therefore, algorithms implementing headway should only project the <i>reference point</i> of the reference GTU
 * on the center line of the adjacent lane, and then calculate the forward position and backward position on the adjacent lane
 * based on the reference point. Still, our human perception of what is parallel and what not, is not reflected by fractional
 * positions. See examples in <a href=
 * "http://simulation.tudelft.nl:8085/browse/OTS-113">http://simulation.tudelft.nl:8085/browse/OTS-113</a>.
 * <p>
 * Copyright (c) 2013-2016 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
 * BSD-style license. See <a href="http://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
 * </p>
 * $LastChangedDate: 2015-07-24 02:58:59 +0200 (Fri, 24 Jul 2015) $, @version $Revision: 1147 $, by $Author: averbraeck $,
 * initial version May 27, 2016 <br>
 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
 * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
 */
public class HeadwayGTUReal extends AbstractHeadwayGTU
{
    /** */
    private static final long serialVersionUID = 20160527L;

    /** stored car following model of the observed GTU. */
    private final CarFollowingModel carFollowingModel;

    /** stored behavioral characteristics of the observed GTU. */
    private final BehavioralCharacteristics behavioralCharacteristics;

    /** stored speed limit info of the observed GTU. */
    private final SpeedLimitInfo speedLimitInfo;

    /**
     * Construct a new Headway information object, for a GTU ahead of us or behind us.
     * @param gtu the observed GTU, can not be null.
     * @param distance the distance to the other object; if this constructor is used, distance cannot be null.
     * @param gtuStatus the observable characteristics of the GTU.
     * @throws GTUException when id is null, objectType is null, or parameters are inconsistent
     */
    public HeadwayGTUReal(final LaneBasedGTU gtu, final Length distance, final GTUStatus... gtuStatus) throws GTUException
    {
        super(gtu.getId(), gtu.getGTUType(), distance, true, gtu.getLength(), gtu.getSpeed(), gtu.getAcceleration(), gtuStatus);
        this.carFollowingModel = gtu.getTacticalPlanner().getCarFollowingModel();
        this.behavioralCharacteristics = gtu.getBehavioralCharacteristics();
        this.speedLimitInfo = getSpeedLimitInfo(gtu);
    }

    /**
     * Construct a new Headway information object, for a GTU parallel with us.
     * @param gtu the observed GTU, can not be null.
     * @param overlapFront the front-front distance to the other GTU; if this constructor is used, this value cannot be null.
     * @param overlap the 'center' overlap with the other GTU; if this constructor is used, this value cannot be null.
     * @param overlapRear the rear-rear distance to the other GTU; if this constructor is used, this value cannot be null.
     * @throws GTUException when id is null, or parameters are inconsistent
     */
    public HeadwayGTUReal(final LaneBasedGTU gtu, final Length overlapFront, final Length overlap, final Length overlapRear)
        throws GTUException
    {
        super(gtu.getId(), gtu.getGTUType(), overlapFront, overlap, overlapRear, true, gtu.getLength(), gtu.getSpeed(), gtu
            .getAcceleration());
        this.carFollowingModel = gtu.getTacticalPlanner().getCarFollowingModel();
        this.behavioralCharacteristics = gtu.getBehavioralCharacteristics();
        this.speedLimitInfo = getSpeedLimitInfo(gtu);
    }
    
    /**
     * Creates speed limit prospect for given GTU.
     * @param gtu gtu to the the speed limit prospect for
     * @return speed limit prospect for given GTU
     */
    // TODO this is a simple fix, and getReferenceLane()
    private SpeedLimitInfo getSpeedLimitInfo(final LaneBasedGTU gtu)
    {
        SpeedLimitInfo sli = new SpeedLimitInfo();
        sli.addSpeedInfo(SpeedLimitTypes.MAX_VEHICLE_SPEED, gtu.getMaximumSpeed());
        try
        {
            sli.addSpeedInfo(SpeedLimitTypes.FIXED_SIGN,
                    gtu.getReferencePosition().getLane().getSpeedLimit(gtu.getGTUType()));
        }
        catch (NetworkException | GTUException exception)
        {
            throw new RuntimeException("Could not obtain speed limit from lane for perception.", exception);
        }
        return sli;
    }

    /** {@inheritDoc} */
    @Override
    public final CarFollowingModel getCarFollowingModel()
    {
        return this.carFollowingModel;
    }

    /** {@inheritDoc} */
    @Override
    public final BehavioralCharacteristics getBehavioralCharacteristics()
    {
        return this.behavioralCharacteristics;
    }

    /** {@inheritDoc} */
    @Override
    public final SpeedLimitInfo getSpeedLimitInfo()
    {
        return this.speedLimitInfo;
    }

}