BasicMobility Class Reference
[mobility - modules handling the mobility of the hosts, basicModules - basic module classes of the MF]

Basic module for all mobility modules. More...

#include <BasicMobility.h>

Inherits BasicModule.

Inherited by CircleMobility, ConstSpeedMobility, LinearMobility, LineSegmentsMobilityBase, MassMobility, and RectangleMobility.

Inheritance diagram for BasicMobility:

[legend]Collaboration diagram for BasicMobility:

[legend]List of all members.

Public Types
enum	BorderPolicy { REFLECT, WRAP, PLACERANDOMLY, RAISEERROR }
	Selects how a node should behave if it reaches the edge of the playground. More...
enum	BasicMobilityMsgKinds { MOVE_HOST = 1050198237, MOVE_TO_BORDER, LAST_BASIC }
	The kind field of messages. More...
enum	BorderHandling {   NOWHERE, X_SMALLER, X_BIGGER, Y_SMALLER,   Y_BIGGER }
	Specifies which border actually has been reached. More...
Public Member Functions
	Module_Class_Members (BasicMobility, BasicModule, 0)
void	handleMessage (cMessage *msg)
	This modules should only receive self-messages.
virtual void	initialize (int)
	Initializes mobility model parameters.
virtual void	finish ()
	Delete dynamically allocated objects.
Protected Member Functions
virtual void	handleSelfMsg (cMessage *)
	Called upon arrival of a self messages.
virtual void	handleBorderMsg (cMessage *)
	Called upon arrival of a border messages.
virtual void	makeMove ()
	Moves the host.
virtual Coord	getRandomPosition ()
	Get a new random position for the host.
void	updatePosition ()
	Update the position information for this node.
double	playgroundSizeX () const
	Returns the width of the playground.
double	playgroundSizeY () const
	Returns the height of the playground.
Border handling
Utility functions to handle hosts that move outside the playground
bool	handleIfOutside (BorderPolicy, Coord &, Coord &, Coord &, double &)
	Main border handling function.
virtual void	fixIfHostGetsOutside ()
	Should be redefined in subclasses.
BorderHandling	checkIfOutside (Coord, Coord &)
	Checks whether the host is outside the playground and returns where.
void	goToBorder (BorderPolicy, BorderHandling, Coord &, Coord &)
	calculate the step to reach the border
void	reflectIfOutside (BorderHandling, Coord &, Coord &, Coord &, double &)
	Utility function to reflect the node if it goes outside the playground.
void	wrapIfOutside (BorderHandling, Coord &, Coord &)
	Utility function to wrap the node to the opposite edge (torus) if it goes outside the playground.
void	placeRandomlyIfOutside (Coord &)
	Utility function to place the node randomly if it goes outside the playground.
Protected Attributes
ChannelControl *	cc
	Pointer to ChannelControl -- these two must know each other.
cModule *	hostPtr
	Pointer to host module, to speed up repeated access.
int	hostId
HostMove	move
	Stores the current position and move pattern of the host.
int	moveCategory
	Store the category of HostMove.
double	updateInterval
	Time interval to update the hosts position.
cMessage *	moveMsg
	Self message to trigger movement.
bool	coreDebug
	debug this core module?

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Detailed Description

Basic module for all mobility modules.

It does not provide mobility at all, so you can use it if you only want to simulate static networks.

BasicMobility provides random placement of hosts and display updates as well as registering with the ChannelControl module. Change notifications about position changes are also posted to the Blackboard.

Another service provided by BasicMobility is bordfer handling. If a host wants to move outside the playground, this situation has to be handled somehow. BasicMobility provides handling for the 4 most common ways for that: reflection, wrapping, random placement and raising an error. The only thing you have to do is to specify your desired border handling in fixIfHostGetsOutside and call it in makeMove.

For most mobility modules the only two functions you need to implement to define your own mobility module are makeMove and fixIfHostGetsOutside..

Author:

Daniel Willkomm, Andras Varga

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Member Enumeration Documentation

enum BasicMobility::BasicMobilityMsgKinds

The kind field of messages. that are used internally by this class have one of these values

enum BasicMobility::BorderHandling

Specifies which border actually has been reached. Enumerator: NOWHERE  not outside the playground X_SMALLER  x smaller than 0 X_BIGGER  x bigger than playground size Y_SMALLER  y smaller than 0 Y_BIGGER  y bigger than playground size

enum BasicMobility::BorderPolicy

Selects how a node should behave if it reaches the edge of the playground. See also: handleIfOutside() Enumerator: REFLECT  reflect off the wall WRAP  reappear at the opposite edge (torus) PLACERANDOMLY  placed at a randomly chosen position on the playground RAISEERROR  stop the simulation with error

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Member Function Documentation

BasicMobility::BorderHandling BasicMobility::checkIfOutside (  Coord  targetPos, Coord &  borderStep )  [protected]

Checks whether the host is outside the playground and returns where. Checks whether the host moved outside and return the border it crossed. Additionally the calculation of the step to reach the border is started.

virtual void BasicMobility::fixIfHostGetsOutside (   )  [inline, protected, virtual]

Should be redefined in subclasses. Should invoke handleIfOutside() and pass the references to the parameters to be modified. Additional action after border handling (such as choosing a new target position if the BorderPolicy is PLACERANDOMLY) should be implemented here. See also: HandleIfOutside Reimplemented in ANSimMobility, BonnMotionMobility, CircleMobility, LinearMobility, MassMobility, RectangleMobility, and TurtleMobility.

Coord BasicMobility::getRandomPosition (   )  [protected, virtual]

Get a new random position for the host. You can redefine this function if you want to use another calculation

void BasicMobility::goToBorder (  BorderPolicy  policy, BorderHandling  wo, Coord &  borderStep, Coord &  borderStart )  [protected]

calculate the step to reach the border Calculate the step to reach the border. Additionally for the WRAP policy the new start position after reaching the border is calculated.

void BasicMobility::handleBorderMsg (  cMessage *  msg  )  [protected, virtual]

Called upon arrival of a border messages. The host actually reached the border, so the startPos has to be updated. Additionally fixIfHostGetsOutside has to be called again to catch cases where the host moved in both (x and y) direction outside the playground.

bool BasicMobility::handleIfOutside (  BorderPolicy  policy, Coord &  stepTarget, Coord &  targetPos, Coord &  step, double &  angle )  [protected]

Main border handling function. This function takes the BorderPolicy and all varaibles to be modified in case a border is reached and invokes the appropriate action. Pass dummy variables if you do not need them. The supproted border policies are REFLECT, WRAP, PLACERANOMLY, and RAISEERROR. The policy and stepTarget are mandatory parameters to pass. stepTarget is used to check whether the host actually moved outside the playground. Additional parameters to pass (in case of non atomic movements) can be targetPos (the target the host is moving to) and step (the size of a step). Angle is the direction in which the host is moving. Parameters: policy  BorderPolicy to use stepTarget  target position of the next step of the host targetPos  target position of the host (for non atomic movement) step  step size of the host (for non atomic movement) angle  direction in which the host is moving Returns: true if host was outside, false otherwise.

void BasicMobility::handleMessage (  cMessage *  msg  )

This modules should only receive self-messages. Dispatches border messages to handleBorderMsg() and all other self-messages to handleSelfMsg()

void BasicMobility::handleSelfMsg (  cMessage *  msg  )  [protected, virtual]

Called upon arrival of a self messages. The only self message possible is to indicate a new movement. If the host is stationary this function is never called. every time a self message arrives makeMove is called to handle the movement. Afterward updatePosition updates the position with the blackboard and the display. Reimplemented in LineSegmentsMobilityBase, and MassMobility.

void BasicMobility::initialize (  int  stage  )  [virtual]

Initializes mobility model parameters. Assigns a pointer to ChannelControl and gets a pointer to its host. Creates a random position for a host if the position is not given as a parameter in "omnetpp.ini". Additionally the registration with ChannelControl is done and it is assured that the position display string tag (p) exists and contains the exact (x) tag. If the speed of the host is bigger than 0 a first MOVE_HOST self message is scheduled in stage 1 Reimplemented from BasicModule. Reimplemented in ANSimMobility, BonnMotionMobility, CircleMobility, ConstSpeedMobility, LinearMobility, MassMobility, RectangleMobility, and TurtleMobility.

virtual void BasicMobility::makeMove (   )  [inline, protected, virtual]

Moves the host. This function is called every time a MOVE_HOST self message arrives. Here you can define the movement pattern for your host. You should call fixIfHostGetsOutside here for border handling Reimplemented in CircleMobility, ConstSpeedMobility, LinearMobility, MassMobility, and RectangleMobility.

void BasicMobility::placeRandomlyIfOutside (  Coord &  targetPos  )  [protected]

Utility function to place the node randomly if it goes outside the playground. Start the host at a new random position. Here the target position is set to the new start position. You have to define a new target postion in fixIfHostGetsOutside to keep the host moving.

void BasicMobility::reflectIfOutside (  BorderHandling  wo, Coord &  stepTarget, Coord &  targetPos, Coord &  step, double &  angle )  [protected]

Utility function to reflect the node if it goes outside the playground. Reflects the host from the playground border. This function can update the target position, the step (for non atomic movements) and the angle. Parameters: stepTarget  target position of the current step of the host targetPos  target position of the host (for non atomic movements) step  step size and direction of the host (for non atomic movements) angle  direction to which the host is moving

void BasicMobility::updatePosition (   )  [protected]

Update the position information for this node. This function tells the Blackboard that the position has changed, and it also moves the host's icon to the new position on the screen. This function has to be called every time the position of the host changes!

void BasicMobility::wrapIfOutside (  BorderHandling  wo, Coord &  stepTarget, Coord &  targetPos )  [protected]

Utility function to wrap the node to the opposite edge (torus) if it goes outside the playground. Wraps the host to the other playground size. Updates the target position. Parameters: stepTarget  target position of the current step of the host targetPos  target position of the host (for non atomic movements)

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The documentation for this class was generated from the following files:

• BasicMobility.h
• BasicMobility.cc

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