/*
* @(#)SplineInterpolator.java 1.0 September 9, 2007
*
* Copyright (c) 2007 Werner Randelshofer
* Hausmatt 10, CH-6405 Goldau, Switzerland
* All rights reserved.
*
* The copyright of this software is owned by Werner Randelshofer.
* You may not use, copy or modify this software, except in
* accordance with the license agreement you entered into with
* Werner Randelshofer. For details see accompanying license terms.
*
* This class uses code from http://timingframework.dev.java.net:
* The derived code is Copyright (c) 2006, Sun Microsystems, Inc
* All rights reserved.
*
* 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 TimingFramework project 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) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
package org.monte.media;
import java.awt.geom.Point2D.Float;
import java.util.Comparator;
import java.util.ArrayList;
import java.awt.geom.Point2D;
import java.util.Arrays;
import static java.lang.Math.*;
/**
* A spline interpolator for use in conjunction with an Animator object.
* <p>
* This class interpolates fractional values using Bezier splines. The anchor
* points for the spline are assumed to be (0, 0) and (1, 1). Control points
* should all be in the range [0, 1].
* <p>
* For more information on how splines are used to interpolate, refer to the
* SMIL specification at http://w3c.org.
* <p>
* <a href="http://www.w3.org/TR/smil/smil-animation.html#animationNS-InterpolationKeysplines"
* >http://www.w3.org/TR/smil/smil-animation.html#animationNS-InterpolationKeysplines</a>
*
* @author Werner Randelshofer
* @version $Id: SplineInterpolator.java 299 2013-01-03 07:40:18Z werner $
*/
public class SplineInterpolator extends AbstractSplineInterpolator {
/** Note: (x0,y0) and (x1,y1) are implicitly (0, 0) and (1,1) respectively. */
private float x1, y1, x2, y2;
/**
* Creates a new instance of SplineInterpolator with the control points
* defined by (x1, y1) and (x2, y2). The anchor points are implicitly
* defined as (0, 0) and (1, 1).
* <p>
* The interpolator runs for one second.
* </p>
*
* @param x1 The x coordinate for the first bezier control point.
* @param y1 The y coordinate for the first bezier control point.
* @param x2 The x coordinate for the second bezier control point.
* @param y2 The x coordinate for the second bezier control point.
*
* @throws IllegalArgumentException This exception is thrown when values
* beyond the allowed [0,1] range are passed in
*/
public SplineInterpolator(float x1, float y1, float x2, float y2) {
this(x1, y1, x2, y2, 1000);
}
/**
* Creates a new instance of SplineInterpolator with the control points
* defined by (x1, y1) and (x2, y2). The anchor points are implicitly
* defined as (0, 0) and (1, 1).
* <p>
* The interpolator runs for the specified time span.
* </p>
* @param x1 The x coordinate for the first bezier control point.
* @param y1 The y coordinate for the first bezier control point.
* @param x2 The x coordinate for the second bezier control point.
* @param y2 The x coordinate for the second bezier control point.
* @param timespan The time span in milliseconds.
*
*
* @throws IllegalArgumentException This exception is thrown when values
* beyond the allowed [0,1] range are passed in
*/
public SplineInterpolator(float x1, float y1, float x2, float y2, long timespan) {
this(x1, y1, x2, y2, false, timespan);
}
/**
* Creates a new instance of SplineInterpolator with the control points
* defined by (x1, y1) and (x2, y2). The anchor points are implicitly
* defined as (0, 0) and (1, 1).
* <p>
* The interpolator runs for the specified time span.
* </p>
* @param x1 The x coordinate for the first bezier control point.
* @param y1 The y coordinate for the first bezier control point.
* @param x2 The x coordinate for the second bezier control point.
* @param y2 The x coordinate for the second bezier control point.
* @param reverse Run interpolator in the reverse direction.
* @param timespan The time span in milliseconds.
*
*
* @throws IllegalArgumentException This exception is thrown when values
* beyond the allowed [0,1] range are passed in
*/
public SplineInterpolator(float x1, float y1, float x2, float y2, boolean reverse, long timespan) {
super((reverse) ? 1f : 0f, (reverse) ? 0f : 1f, timespan);
if (x1 < 0 || x1 > 1.0f
|| y1 < 0 || y1 > 1.0f
|| x2 < 0 || x2 > 1.0f
|| y2 < 0 || y2 > 1.0f) {
throw new IllegalArgumentException("Control points must be in "
+ "the range [0, 1]:");
}
this.x1 = x1;
this.y1 = y1;
this.x2 = x2;
this.y2 = y2;
updateFractions(100);
}
/**
* Evaluates the spline function at curve parameter time t.
*/
@Override
public Point2D.Float getXY(float t, Point2D.Float p) {
if (p == null) {
p = new Point2D.Float();
}
float invT = (1 - t);
float b1 = 3 * t * (invT * invT);
float b2 = 3 * (t * t) * invT;
float b3 = t * t * t;
p.setLocation((b1 * x1) + (b2 * x2) + b3, (b1 * y1) + (b2 * y2) + b3);
return p;
}
/**
* Evaluates the spline function at curve parameter time t.
*/
@Override
public float getY(float t) {
float invT = (1 - t);
float b1 = 3 * t * (invT * invT);
float b2 = 3 * (t * t) * invT;
float b3 = t * t * t;
return (b1 * y1) + (b2 * y2) + b3;
}
}