/*
* __ .__ .__ ._____.
* _/ |_ _______ __|__| ____ | | |__\_ |__ ______
* \ __\/ _ \ \/ / |/ ___\| | | || __ \ / ___/
* | | ( <_> > <| \ \___| |_| || \_\ \\___ \
* |__| \____/__/\_ \__|\___ >____/__||___ /____ >
* \/ \/ \/ \/
*
* 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;
import spimedb.util.geom.Vec2D;
/**
* Implementations of 2D interpolation functions (currently only bilinear).
*/
public class Interpolation2D {
/**
* @param x
* x coord of point to filter
* @param y
* y coord of point to filter
* @param x1
* x coord of top-left corner
* @param y1
* y coord of top-left corner
* @param x2
* x coord of bottom-right corner
* @param y2
* y coord of bottom-right corner
* @param tl
* top-left value
* @param tr
* top-right value
* @param bl
* bottom-left value
* @param br
* bottom-right value
* @return interpolated value
*/
public static float bilinear(double x, double y, double x1, double y1,
double x2, double y2, float tl, float tr, float bl, float br) {
double denom = 1.0 / ((x2 - x1) * (y2 - y1));
double dx1 = (x - x1) * denom;
double dx2 = (x2 - x) * denom;
double dy1 = y - y1;
double dy2 = y2 - y;
return (float) (tl * dx2 * dy2 + tr * dx1 * dy2 + bl * dx2 * dy1 + br
* dx1 * dy1);
}
/**
* @param p
* point to filter
* @param p1
* top-left corner
* @param p2
* bottom-right corner
* @param tl
* top-left value
* @param tr
* top-right value
* @param bl
* bottom-left value
* @param br
* bottom-right value
* @return interpolated value
*/
public static float bilinear(Vec2D p, Vec2D p1, Vec2D p2, float tl,
float tr, float bl, float br) {
return bilinear(p.x, p.y, p1.x, p1.y, p2.x, p2.y, tl, tr, bl, br);
}
}