1 package org.opentrafficsim.road.gtu.lane.perception;
2
3 import org.djunits.unit.LengthUnit;
4 import org.djunits.value.vdouble.scalar.Acceleration;
5 import org.djunits.value.vdouble.scalar.Length;
6 import org.djunits.value.vdouble.scalar.Speed;
7
8 /**
9 * Container for a reference to information about a headway with just a distance, without any further information about the
10 * object; it assumes a speed of 0 at the headway, so it also good to store information about a lane drop. The reason for
11 * storing a speed of zero at the end of a maximum headway is that we did not check the conditions beyond that point. A GTU or
12 * lane drop could be right behind the last point we checked.
13 * <p>
14 * Copyright (c) 2013-2015 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
15 * BSD-style license. See <a href="http://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
16 * <p>
17 * @version $Revision: 1368 $, $LastChangedDate: 2015-09-02 00:20:20 +0200 (Wed, 02 Sep 2015) $, by $Author: averbraeck $,
18 * initial version 11 feb. 2015 <br>
19 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
20 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
21 */
22 public class HeadwayDistance implements Headway
23 {
24 /** */
25 private static final long serialVersionUID = 20160410L;
26
27 /** the distance of the headway. */
28 private final Length distance;
29
30 /**
31 * Construct a new Headway information object with just a distance, without any further information about the object; it
32 * assumes a speed of 0 at the headway, so it also good to store information about a lane drop.
33 * @param distance the distance that needs to be stored.
34 */
35 public HeadwayDistance(final double distance)
36 {
37 this(new Length(distance, LengthUnit.SI));
38 }
39
40 /**
41 * Construct a new Headway information object with just a distance, without any further information about the object; it
42 * assumes a speed of 0 at the headway, so it also good to store information about a lane drop.
43 * @param distance the distance that needs to be stored.
44 */
45 public HeadwayDistance(final Length distance)
46 {
47 this.distance = distance;
48 }
49
50 /** {@inheritDoc} */
51 @Override
52 public final String getId()
53 {
54 return "DISTANCE";
55 }
56
57 /** {@inheritDoc} */
58 @Override
59 public final Speed getSpeed()
60 {
61 return Speed.ZERO;
62 }
63
64 /** {@inheritDoc} */
65 @Override
66 public final Length getDistance()
67 {
68 return this.distance;
69 }
70
71 /** {@inheritDoc} */
72 @Override
73 public final ObjectType getObjectType()
74 {
75 return ObjectType.DISTANCEONLY;
76 }
77
78 /** {@inheritDoc} */
79 @Override
80 public final Acceleration getAcceleration()
81 {
82 return Acceleration.ZERO;
83 }
84
85 /** {@inheritDoc} */
86 @Override
87 public final Length getOverlapFront()
88 {
89 return null;
90 }
91
92 /** {@inheritDoc} */
93 @Override
94 public final Length getOverlapRear()
95 {
96 return null;
97 }
98
99 /** {@inheritDoc} */
100 @Override
101 public final Length getOverlap()
102 {
103 return null;
104 }
105
106 /** {@inheritDoc} */
107 @Override
108 public final boolean isAhead()
109 {
110 return this.distance.ge(Length.ZERO);
111 }
112
113 /** {@inheritDoc} */
114 @Override
115 public final boolean isBehind()
116 {
117 return this.distance.lt(Length.ZERO);
118 }
119
120 /** {@inheritDoc} */
121 @Override
122 public final boolean isParallel()
123 {
124 return false;
125 }
126
127 /** {@inheritDoc} */
128 @Override
129 public final String toString()
130 {
131 return "HeadwayDistance [distance=" + this.distance + "]";
132 }
133
134 }