1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2006,2007 INRIA
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation;
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
17  *
18  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
19  */
20 #include "random-walk-2d-mobility-model.h"
21 #include "ns3/enum.h"
22 #include "ns3/double.h"
23 #include "ns3/string.h"
24 #include "ns3/pointer.h"
25 #include "ns3/simulator.h"
26 #include "ns3/log.h"
27 #include <cmath>
28 
29 namespace ns3 {
30 
31 NS_LOG_COMPONENT_DEFINE ("RandomWalk2d");
32 
33 NS_OBJECT_ENSURE_REGISTERED (RandomWalk2dMobilityModel);
34 
35 TypeId
GetTypeId(void)36 RandomWalk2dMobilityModel::GetTypeId (void)
37 {
38   static TypeId tid = TypeId ("ns3::RandomWalk2dMobilityModel")
39     .SetParent<MobilityModel> ()
40     .SetGroupName ("Mobility")
41     .AddConstructor<RandomWalk2dMobilityModel> ()
42     .AddAttribute ("Bounds",
43                    "Bounds of the area to cruise.",
44                    RectangleValue (Rectangle (0.0, 100.0, 0.0, 100.0)),
45                    MakeRectangleAccessor (&RandomWalk2dMobilityModel::m_bounds),
46                    MakeRectangleChecker ())
47     .AddAttribute ("Time",
48                    "Change current direction and speed after moving for this delay.",
49                    TimeValue (Seconds (1.0)),
50                    MakeTimeAccessor (&RandomWalk2dMobilityModel::m_modeTime),
51                    MakeTimeChecker ())
52     .AddAttribute ("Distance",
53                    "Change current direction and speed after moving for this distance.",
54                    DoubleValue (1.0),
55                    MakeDoubleAccessor (&RandomWalk2dMobilityModel::m_modeDistance),
56                    MakeDoubleChecker<double> ())
57     .AddAttribute ("Mode",
58                    "The mode indicates the condition used to "
59                    "change the current speed and direction",
60                    EnumValue (RandomWalk2dMobilityModel::MODE_DISTANCE),
61                    MakeEnumAccessor (&RandomWalk2dMobilityModel::m_mode),
62                    MakeEnumChecker (RandomWalk2dMobilityModel::MODE_DISTANCE, "Distance",
63                                     RandomWalk2dMobilityModel::MODE_TIME, "Time"))
64     .AddAttribute ("Direction",
65                    "A random variable used to pick the direction (radians).",
66                    StringValue ("ns3::UniformRandomVariable[Min=0.0|Max=6.283184]"),
67                    MakePointerAccessor (&RandomWalk2dMobilityModel::m_direction),
68                    MakePointerChecker<RandomVariableStream> ())
69     .AddAttribute ("Speed",
70                    "A random variable used to pick the speed (m/s).",
71                    StringValue ("ns3::UniformRandomVariable[Min=2.0|Max=4.0]"),
72                    MakePointerAccessor (&RandomWalk2dMobilityModel::m_speed),
73                    MakePointerChecker<RandomVariableStream> ());
74   return tid;
75 }
76 
77 void
DoInitialize(void)78 RandomWalk2dMobilityModel::DoInitialize (void)
79 {
80   DoInitializePrivate ();
81   MobilityModel::DoInitialize ();
82 }
83 
84 void
DoInitializePrivate(void)85 RandomWalk2dMobilityModel::DoInitializePrivate (void)
86 {
87   m_helper.Update ();
88   double speed = m_speed->GetValue ();
89   double direction = m_direction->GetValue ();
90   Vector vector (std::cos (direction) * speed,
91                  std::sin (direction) * speed,
92                  0.0);
93   m_helper.SetVelocity (vector);
94   m_helper.Unpause ();
95 
96   Time delayLeft;
97   if (m_mode == RandomWalk2dMobilityModel::MODE_TIME)
98     {
99       delayLeft = m_modeTime;
100     }
101   else
102     {
103       delayLeft = Seconds (m_modeDistance / speed);
104     }
105   DoWalk (delayLeft);
106 }
107 
108 void
DoWalk(Time delayLeft)109 RandomWalk2dMobilityModel::DoWalk (Time delayLeft)
110 {
111   Vector position = m_helper.GetCurrentPosition ();
112   Vector speed = m_helper.GetVelocity ();
113   Vector nextPosition = position;
114   nextPosition.x += speed.x * delayLeft.GetSeconds ();
115   nextPosition.y += speed.y * delayLeft.GetSeconds ();
116   m_event.Cancel ();
117   if (m_bounds.IsInside (nextPosition))
118     {
119       m_event = Simulator::Schedule (delayLeft, &RandomWalk2dMobilityModel::DoInitializePrivate, this);
120     }
121   else
122     {
123       nextPosition = m_bounds.CalculateIntersection (position, speed);
124       Time delay = Seconds ((nextPosition.x - position.x) / speed.x);
125       m_event = Simulator::Schedule (delay, &RandomWalk2dMobilityModel::Rebound, this,
126                                      delayLeft - delay);
127     }
128   NotifyCourseChange ();
129 }
130 
131 void
Rebound(Time delayLeft)132 RandomWalk2dMobilityModel::Rebound (Time delayLeft)
133 {
134   m_helper.UpdateWithBounds (m_bounds);
135   Vector position = m_helper.GetCurrentPosition ();
136   Vector speed = m_helper.GetVelocity ();
137   switch (m_bounds.GetClosestSide (position))
138     {
139     case Rectangle::RIGHT:
140     case Rectangle::LEFT:
141       speed.x = -speed.x;
142       break;
143     case Rectangle::TOP:
144     case Rectangle::BOTTOM:
145       speed.y = -speed.y;
146       break;
147     }
148   m_helper.SetVelocity (speed);
149   m_helper.Unpause ();
150   DoWalk (delayLeft);
151 }
152 
153 void
DoDispose(void)154 RandomWalk2dMobilityModel::DoDispose (void)
155 {
156   // chain up
157   MobilityModel::DoDispose ();
158 }
159 Vector
DoGetPosition(void) const160 RandomWalk2dMobilityModel::DoGetPosition (void) const
161 {
162   m_helper.UpdateWithBounds (m_bounds);
163   return m_helper.GetCurrentPosition ();
164 }
165 void
DoSetPosition(const Vector & position)166 RandomWalk2dMobilityModel::DoSetPosition (const Vector &position)
167 {
168   NS_ASSERT (m_bounds.IsInside (position));
169   m_helper.SetPosition (position);
170   m_event.Cancel ();
171   m_event = Simulator::ScheduleNow (&RandomWalk2dMobilityModel::DoInitializePrivate, this);
172 }
173 Vector
DoGetVelocity(void) const174 RandomWalk2dMobilityModel::DoGetVelocity (void) const
175 {
176   return m_helper.GetVelocity ();
177 }
178 int64_t
DoAssignStreams(int64_t stream)179 RandomWalk2dMobilityModel::DoAssignStreams (int64_t stream)
180 {
181   m_speed->SetStream (stream);
182   m_direction->SetStream (stream + 1);
183   return 2;
184 }
185 
186 
187 } // namespace ns3
188