/*
* __ .__ .__ ._____.
* _/ |_ _______ __|__| ____ | | |__\_ |__ ______
* \ __\/ _ \ \/ / |/ ___\| | | || __ \ / ___/
* | | ( <_> > <| \ \___| |_| || \_\ \\___ \
* |__| \____/__/\_ \__|\___ >____/__||___ /____ >
* \/ \/ \/ \/
*
* Copyright (c) 2006-2011 Karsten Schmidt
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* http://creativecommons.org/licenses/LGPL/2.1/
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*/
package spimedb.util.math;
/**
* Implementation of the circular interpolation function.
*
* i = a-(b-a) * (sqrt(1 - (1 - f) * (1 - f) ))
*/
public class CircularInterpolation implements InterpolateStrategy {
protected boolean isFlipped;
public CircularInterpolation() {
this(false);
}
/**
* The interpolation slope can be flipped to have its steepest ascent
* towards the end value, rather than at the beginning in the default
* configuration.
*
* @param isFlipped
* true, if slope is inverted
*/
public CircularInterpolation(boolean isFlipped) {
this.isFlipped = isFlipped;
}
public double interpolate(double a, double b, double f) {
if (isFlipped) {
return a - (b - a) * (Math.sqrt(1 - f * f) - 1);
} else {
f = 1 - f;
return a + (b - a) * (Math.sqrt(1 - f * f));
}
}
public float interpolate(float a, float b, float f) {
if (isFlipped) {
return a - (b - a) * ((float) Math.sqrt(1 - f * f) - 1);
} else {
f = 1 - f;
return a + (b - a) * ((float) Math.sqrt(1 - f * f));
}
}
public void setFlipped(boolean isFlipped) {
this.isFlipped = isFlipped;
}
}