1 /* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */

     2 /*

     3  * Copyright (c) 2009 Phillip Sitbon

     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: Phillip Sitbon <phillip@sitbon.net>

    19  */

    20 #ifndef WAYPOINT_MOBILITY_MODEL_H

    21 #define WAYPOINT_MOBILITY_MODEL_H

    22 

    23 #include <stdint.h>

    24 #include <deque>

    25 #include "mobility-model.h"

    26 #include "ns3/vector.h"

    27 #include "waypoint.h"

    28 

    29 namespace ns3 {

    30 

    31 /**

    32  * \brief a waypoint-based mobility model

    33  *

    34  * Each object determines its velocity and position at a given time

    35  * from a set of ns3::Waypoint objects. The position of each object

    36  * is not updated unless queried, and past waypoints are discarded

    37  * after the current simulation time greater than their time value.

    38  * 

    39  * The initial position of each object corresponds to the position of

    40  * the first waypoint, and the initial velocity of each object is zero.

    41  * Upon reaching the last waypoint, object positions becomes static and

    42  * velocity is zero.

    43  *

    44  * When a node is in between waypoints (in time), it moves with a constant

    45  * velocity between the position at the previous waypoint and the position

    46  * at the current waypoint. To make a node hold a certain position for a

    47  * time interval, two waypoints with the same position (but different times)

    48  * should be inserted sequentially.

    49  *

    50  * Waypoints can be added at any time, and setting the current position

    51  * of an object will set its velocity to zero until the next waypoint time

    52  * (at which time the object jumps to the next waypoint), unless there are

    53  * no more waypoints in which case it will not change without user

    54  * intervention.

    55  *

    56  */

    57 class WaypointMobilityModel : public MobilityModel

    58 {

    59  public:

    60   static TypeId GetTypeId (void);

    61 

    62   /**

    63    * Create a path with no waypoints at location (0,0,0).

    64    */

    65   WaypointMobilityModel ();

    66   virtual ~WaypointMobilityModel ();

    67 

    68   /**

    69    * \param waypoint waypoint to append to the object path.

    70    *

    71    * Add a waypoint to the path of the object. The time must

    72    * be greater than the previous waypoint added, otherwise

    73    * a fatal error occurs. The first waypoint is set as the

    74    * current position with a velocity of zero.

    75    * 

    76    */

    77   void AddWaypoint (const Waypoint &waypoint);

    78 

    79   /**

    80    * Get the waypoint that this object is traveling towards.

    81    */

    82   Waypoint GetNextWaypoint (void) const;

    83 

    84   /**

    85    * Get the number of waypoints left for this object, excluding

    86    * the next one.

    87    */

    88   uint32_t WaypointsLeft (void) const;

    89 

    90   /**

    91    * Clear any existing waypoints and set the current waypoint

    92    * time to infinity. Calling this is only an optimization and

    93    * not required. After calling this function, adding waypoints

    94    * behaves as it would for a new object.

    95    */

    96   void EndMobility (void);

    97 

    98  private:

    99   void Update (void) const;

   100   virtual void DoDispose (void);

   101   virtual Vector DoGetPosition (void) const;

   102   virtual void DoSetPosition (const Vector &position);

   103   virtual Vector DoGetVelocity (void) const;

   104 

   105   bool m_first;

   106   mutable std::deque<Waypoint> m_waypoints;

   107   mutable Waypoint m_current;

   108   mutable Waypoint m_next;

   109   mutable Vector m_velocity;

   110 };

   111 

   112 } // namespace ns3

   113 

   114 #endif /* WAYPOINT_MOBILITY_MODEL_H */

   115