/**
* Copyright (c) 2003-2009, Xith3D Project Group all rights reserved.
*
* Portions based on the Java3D interface, Copyright by Sun Microsystems.
* Many thanks to the developers of Java3D and Sun Microsystems for their
* innovation and design.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the 'Xith3D Project Group' nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) A
* RISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE
*/
package org.xith3d.utility.interpolate;
import org.openmali.FastMath;
import org.xith3d.loop.UpdatingThread.TimingMode;
/**
* Creates a time based interpolator for angles. The result is an angle in
* radians appropriate to use as a euler angle. The speed is specfied in
* radians/second. The interpolator can be increasing or decreasing.
*
* Time values must always be in microseconds!
*
* @author David Yazel
* @author Marvin Froehlich (aka Qudus)
*/
public class AngleInterpolater
{
private static final int STATE_INCREASING = 1;
private static final int STATE_DECREASING = 2;
private static final int STATE_STOPPED = 3;
private int state = STATE_STOPPED;
private float start; // starting value
private float speed; // rdians per second
private float min; // minimum value
private float max; // maximum value
private boolean wraps; // wrap between min/max
private float value; // current value
private long lastMicros; // last time we took a reading
/**
* Constructs the AngleInterpolator.
*
* @param value Current angle
* @param speed Radians per second that we change
* @param min Minimum acceptable angle in radians
* @param max Maximum acceptable angle in radians
* @param wraps Determines if the angle wraps to MIN when it reaches MAX and visa versa
*/
public AngleInterpolater( float value, float speed, float min, float max, boolean wraps )
{
this.start = value;
this.value = value;
this.speed = speed;
this.min = min;
this.max = max;
this.wraps = wraps;
this.lastMicros = -1;
}
/**
* Constructs the AngleInterpolator.
*
* @param speed Radians per second that we change
* @param min Minimum acceptable angle in radians
* @param max Maximum acceptable angle in radians
* @param wraps Determines if the angle wraps to MIN when it reaches MAX and visa versa
*/
public AngleInterpolater( float speed, float min, float max, boolean wraps )
{
this( 0.0f, speed, min, max, wraps );
}
/**
* Constructs the AngleInterpolator.
*
* @param speed Radians per second that we change
* @param wraps Determines if the angle wraps to MIN when it reaches MAX and visa versa
*/
public AngleInterpolater( float speed, boolean wraps )
{
this( 0.0f, speed, 0.0f, FastMath.TWO_PI, wraps );
}
/**
* Constructs the AngleInterpolator.
*
* @param speed Radians per second that we change
*/
public AngleInterpolater( float speed )
{
this( speed, true );
}
public AngleInterpolater()
{
this( 0.0f, FastMath.TWO_PI, 0.0f, FastMath.TWO_PI, true );
}
public void stop()
{
state = STATE_STOPPED;
}
public boolean isStopped()
{
return ( state == STATE_STOPPED );
}
public void startIncreasing( long startTime )
{
if ( state == STATE_STOPPED )
{
lastMicros = startTime;
}
state = STATE_INCREASING;
}
public void resetIncreasing( long startTime )
{
value = start;
lastMicros = startTime;
state = STATE_INCREASING;
}
public void resetDecreasing( long startTime )
{
value = start;
lastMicros = startTime;
state = STATE_DECREASING;
}
public void startDecreasing( long startTime )
{
if ( state == STATE_STOPPED )
{
lastMicros = startTime;
}
state = STATE_DECREASING;
}
public void setValue( float angle )
{
value = angle;
}
public final float getValue( long gameMicros )
{
if ( lastMicros == -1L )
{
lastMicros = gameMicros;
}
float elapsedSeconds = ( (float)( gameMicros - lastMicros ) ) / 1000000f;
if ( state == STATE_INCREASING )
{
value = value + ( elapsedSeconds * speed );
if ( value > max )
{
if ( wraps )
{
value = min + ( value - max );
}
else
{
state = STATE_STOPPED;
value = max;
}
}
}
else if ( state == STATE_DECREASING )
{
value = value - ( elapsedSeconds * speed );
if ( value < min )
{
if ( wraps )
{
value = max - ( min - value );
}
else
{
state = STATE_STOPPED;
value = min;
}
}
}
lastMicros = gameMicros;
return ( value );
}
public final float getValue( long gameTime, TimingMode timingMode )
{
return ( getValue( timingMode.getMicroSeconds( gameTime ) ) );
}
public void setStartValue( float startVal )
{
this.start = startVal;
}
public float getStartValue()
{
return ( start );
}
public void setSpeed( float speed )
{
this.speed = speed;
}
public float getSpeed()
{
return ( speed );
}
public void setMinValue( float min )
{
this.min = min;
}
public float getMinValue()
{
return ( min );
}
public void setMaxValue( float max )
{
this.max = max;
}
public float getMaxValue()
{
return ( max );
}
public void setWraps( boolean wraps )
{
this.wraps = wraps;
}
public boolean getWraps()
{
return ( wraps );
}
}