/*---

    iGeo - http://igeo.jp

    Copyright (c) 2002-2012 Satoru Sugihara

    This file is part of iGeo.

    iGeo 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, version 3.

    iGeo 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 iGeo.  If not, see <http://www.gnu.org/licenses/>.

---*/

package igeo;

/**
   A subclass of IMap defined by subtraction of two maps.
   Output value is crampped with 0.0 - 1.0.
   
   @author Satoru Sugihara
   @version 0.7.0.0;
*/
public class ISubtractMap extends IMap{
    public IMap map1, map2;
    public ISubtractMap(IMap m1,IMap m2){ map1=m1; map2=m2; }
    public double get(double u, double v){
	double val = map1.get(u,v) - map2.get(u,v);
	if(val>1) return 1;
	if(val<0) return 0;
	return val;
    }
    public void flipU(){ map1.flipU(); map2.flipU(); } //is it ok to modify the original?
    public void flipV(){ map1.flipV(); map2.flipV(); } //is it ok to modify the original?
}
