org.jeospace.navigation
Class SphericalInterpolator

java.lang.Object
  org.jeospace.navigation.SphericalInterpolator

All Implemented Interfaces:

Position, PositionInterpolator

public class SphericalInterpolator

extends java.lang.Object

implements PositionInterpolator

A position interpolator that takes Polar coordinates as arguments. The interpolation follows the shortest path from initial position to final position along a "great circle" path.

Version:

$Revision: 1.2 $

Author:

Rex Melton

See Also:

Alpha, Cartesian, Polar

Constructor Summary

SphericalInterpolator(Polar startPosition, Polar endPosition, Length scale)
Construct an instance

Method Summary

void	addInterpolationListener(InterpolationListener il) Add a listener to this interpolator
void	enablePosition(boolean enabled) Set the state of the interpolator to update it's Alpha in response to update( ) calls.
protected void	fireInterpolationEvent(int id) Deliver events to the listeners
void	get(Cartesian cartesian) Return the position as a Cartesian
Alpha	getAlpha() Return the Alpha object
Polar	getPolar() Return the positioning data in a Polar coordinate object.
void	removeInterpolationListener(InterpolationListener il) Remove a listener from this interpolator
void	setAlpha(Alpha alpha) Set the Alpha object to drive the interpolator
void	updatePosition(double timeValue) Process any position changes for the next simulation frame.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SphericalInterpolator

public SphericalInterpolator(Polar startPosition,
                             Polar endPosition,
                             Length scale)

Construct an instance

Parameters:

startPosition - the initial position at alpha value of 0.0

endPosition - the final position at alpha value of 1.0

Method Detail

setAlpha

public void setAlpha(Alpha alpha)

Set the Alpha object to drive the interpolator

Specified by:

setAlpha in interface PositionInterpolator

Parameters:

alpha - the Alpha object to install

getAlpha

public Alpha getAlpha()

Return the Alpha object

Specified by:

getAlpha in interface PositionInterpolator

Returns:

the Alpha object

updatePosition

public void updatePosition(double timeValue)

Process any position changes for the next simulation frame. This method updates the Alpha of this interpolator by a single increment.

Specified by:

updatePosition in interface Position

Parameters:

timeValue - the time value is ignored

enablePosition

public void enablePosition(boolean enabled)

Set the state of the interpolator to update it's Alpha in response to update( ) calls.

Specified by:

enablePosition in interface Position

Parameters:

enabled - true if the object should update it's Alpha in response to update( ) calls, false if the object should NOT update it's Alpha in response to update( ) calls.

get

public void get(Cartesian cartesian)

Return the position as a Cartesian

Specified by:

get in interface Position

Parameters:

cartesian - the Cartesian object to initialize with the position calculated at the fraction value of the Alpha

getPolar

public Polar getPolar()

Return the positioning data in a Polar coordinate object.

Specified by:

getPolar in interface Position

Returns:

the positioning data in a Polar coordinate object.

addInterpolationListener

public void addInterpolationListener(InterpolationListener il)

Add a listener to this interpolator

Specified by:

addInterpolationListener in interface PositionInterpolator

Parameters:

il - the InterpolationListener

removeInterpolationListener

public void removeInterpolationListener(InterpolationListener il)

Remove a listener from this interpolator

Specified by:

removeInterpolationListener in interface PositionInterpolator

Parameters:

il - the InterpolationListener

fireInterpolationEvent

protected void fireInterpolationEvent(int id)

Deliver events to the listeners

Parameters:

id - the InterpolationEvent id