/*
 * $RCSfile: LightIntensityPathInterpolator.java,v $
 *
 * Copyright (c) 2007 Sun Microsystems, Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions
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 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
 * EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL
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 * You acknowledge that this software is not designed, licensed or
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 * $Revision: 1.4 $
 * $Date: 2007/02/09 17:20:07 $
 * $State: Exp $
 */

package com.sun.j3d.loaders.lw3d;

import java.util.*;

import javax.media.j3d.Alpha;
import javax.media.j3d.Light;

/**
 * This Interpolator object modifies the intensity of a Light object
 * according to the keyframes in a light intensity envelope
 */
class LightIntensityPathInterpolator extends FloatValueInterpolator {

    LwLightObject theLight;

    LightIntensityPathInterpolator(Alpha alpha,
					  float knots[],
					  float values[],
					  Object target) {

	super(alpha, knots, values);
	theLight = (LwLightObject)target;
    }

    /**
     * This method is invoked by the behavior scheduler every frame.  It maps
     * the alpha value that corresponds to the current time into the 
     * appropriate light intensity for that time as obtained by interpolating
     * between the light intensity values for each knot point that were passed  
     * to this class.
     * @param criteria enumeration of criteria that have triggered this wakeup
     */

    public void processStimulus(Enumeration criteria) {
        // Handle stimulus

        if (this.getAlpha() != null) {

            // Let FloatValueInterpolator calculate the correct 
            // interpolated value
            computePathInterpolation();

            // Set light intensity to the value calculated by 
            // FloatValueInterpolator
            if (theLight != null) 
               theLight.setIntensity(currentValue);

            if ((this.getAlpha()).finished())
                return;
        }

        wakeupOn(defaultWakeupCriterion);

    }

}

