AnticipationSpeed.java

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

import java.util.function.Supplier;

import org.djunits.value.vdouble.scalar.Length;
import org.djunits.value.vdouble.scalar.Speed;
import org.opentrafficsim.core.gtu.GTU;
import org.opentrafficsim.road.gtu.lane.LaneBasedGTU;
import org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable.Intermediate;
import org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable.PerceptionAccumulator;
import org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable.PerceptionCollector;
import org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable.PerceptionFinalizer;
import org.opentrafficsim.road.gtu.lane.perception.RelativeLane;
import org.opentrafficsim.road.gtu.lane.perception.categories.AnticipationSpeed.SpeedSet;

/**
 * Collector of leaders which derives an set of anticipation speeds from a lane. This includes all GTUs on the lane (current),
 * all GTUs indicating left (left) and all GTUs indicating right (right).
 * <p>
 * Copyright (c) 2013-2019 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/node/13">OpenTrafficSim License</a>.
 * <p>
 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 2 mrt. 2018 <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 AnticipationSpeed implements PerceptionCollector<SpeedSet, LaneBasedGTU, SpeedSet>
{

    /** Desired speed. */
    private double desiredSpeed;

    /** Look-ahead distance. */
    private double x0;

    /** Lane. */
    private RelativeLane lane;

    /**
     * Constructor.
     * @param desiredSpeed Speed; desired speed
     * @param lookAhead Length; look-ahead distance
     * @param lane RelativeLane; lane
     */
    public AnticipationSpeed(final Speed desiredSpeed, final Length lookAhead, final RelativeLane lane)
    {
        this.desiredSpeed = desiredSpeed.si;
        this.x0 = lookAhead.si;
        this.lane = lane;
    }

    /** {@inheritDoc} */
    @Override
    public Supplier<SpeedSet> getIdentity()
    {
        return new Supplier<SpeedSet>()
        {
            @SuppressWarnings("synthetic-access")
            @Override
            public SpeedSet get()
            {
                SpeedSet identity = new SpeedSet();
                identity.left = AnticipationSpeed.this.desiredSpeed;
                identity.current = AnticipationSpeed.this.desiredSpeed;
                identity.right = AnticipationSpeed.this.desiredSpeed;
                return identity;
            }
        };
    }

    /** {@inheritDoc} */
    @Override
    public PerceptionAccumulator<LaneBasedGTU, SpeedSet> getAccumulator()
    {
        return new PerceptionAccumulator<LaneBasedGTU, SpeedSet>()
        {
            @SuppressWarnings("synthetic-access")
            @Override
            public Intermediate<SpeedSet> accumulate(final Intermediate<SpeedSet> intermediate, final LaneBasedGTU object,
                    final Length distance)
            {
                double v = anticipateSingle(object, distance);
                if (AnticipationSpeed.this.lane.getNumLanes() < 2)
                {
                    intermediate.getObject().current =
                            intermediate.getObject().current < v ? intermediate.getObject().current : v;
                }
                if (!AnticipationSpeed.this.lane.isCurrent())
                {
                    if (AnticipationSpeed.this.lane.isRight())
                    {
                        if (object.getTurnIndicatorStatus().isLeft())
                        {
                            intermediate.getObject().left =
                                    intermediate.getObject().left < v ? intermediate.getObject().left : v;
                        }
                    }
                    else
                    {
                        if (object.getTurnIndicatorStatus().isRight())
                        {
                            intermediate.getObject().right =
                                    intermediate.getObject().right < v ? intermediate.getObject().right : v;
                        }
                    }
                }
                return intermediate;
            }
        };

    }

    /**
     * Anticipate a single leader by possibly lowering the anticipation speed.
     * @param gtu GTU; GTU
     * @param distance Length; distance to GTU
     * @return possibly lowered anticipation speed
     */
    final double anticipateSingle(final GTU gtu, final Length distance)
    {
        Speed speed = gtu.getSpeed();
        double v = speed == null ? 0.0 : speed.si;
        if (v > this.desiredSpeed || distance.si > this.x0)
        {
            return this.desiredSpeed;
        }
        double f = distance.si / this.x0;
        f = f < 0.0 ? 0.0 : f > 1.0 ? 1.0 : f;
        return (1 - f) * v + f * this.desiredSpeed;
    }

    /** {@inheritDoc} */
    @Override
    public PerceptionFinalizer<SpeedSet, SpeedSet> getFinalizer()
    {
        return new PerceptionFinalizer<SpeedSet, SpeedSet>()
        {
            @Override
            public SpeedSet collect(final SpeedSet intermediate)
            {
                return intermediate;
            }
        };
    }

    /**
     * Class to contain info from 1 lane, regarding 3 lanes.
     * <p>
     * Copyright (c) 2013-2019 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/node/13">OpenTrafficSim License</a>.
     * <p>
     * @version $Revision$, $LastChangedDate$, by $Author$, initial version 8 mrt. 2018 <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 static class SpeedSet
    {
        /** Speed regarding the left lane. */
        private double left = Double.POSITIVE_INFINITY;

        /** Speed regarding the current lane. */
        private double current = Double.POSITIVE_INFINITY;

        /** Speed regarding the right lane. */
        private double right = Double.POSITIVE_INFINITY;

        /**
         * Returns the speed regarding the left lane.
         * @return Speed; speed regarding the left lane
         */
        public final Speed getLeft()
        {
            return Speed.createSI(this.left);
        }

        /**
         * Returns the speed regarding the current lane.
         * @return Speed; speed regarding the current lane
         */
        public final Speed getCurrent()
        {
            return Speed.createSI(this.current);
        }

        /**
         * Returns the speed regarding the right lane.
         * @return Speed; speed regarding the right lane
         */
        public final Speed getRight()
        {
            return Speed.createSI(this.right);
        }
    }

}