001/**
002 *
003 * Copyright (c) 2014, the Railo Company Ltd. All rights reserved.
004 *
005 * This library is free software; you can redistribute it and/or
006 * modify it under the terms of the GNU Lesser General Public
007 * License as published by the Free Software Foundation; either 
008 * version 2.1 of the License, or (at your option) any later version.
009 * 
010 * This library is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013 * Lesser General Public License for more details.
014 * 
015 * You should have received a copy of the GNU Lesser General Public 
016 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
017 * 
018 **/
019/*
020*
021
022Licensed under the Apache License, Version 2.0 (the "License");
023you may not use this file except in compliance with the License.
024You may obtain a copy of the License at
025
026   http://www.apache.org/licenses/LICENSE-2.0
027
028Unless required by applicable law or agreed to in writing, software
029distributed under the License is distributed on an "AS IS" BASIS,
030WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
031See the License for the specific language governing permissions and
032limitations under the License.
033*/
034
035package lucee.runtime.img.math;
036
037public class TurbulenceFunction extends CompoundFunction2D {
038
039        private float octaves;
040
041        public TurbulenceFunction(Function2D basis, float octaves) {
042                super(basis);
043                this.octaves = octaves;
044        }
045        
046        public void setOctaves(float octaves) {
047                this.octaves = octaves;
048        }
049
050        public float getOctaves() {
051                return octaves;
052        }
053
054        public float evaluate(float x, float y) {
055                float t = 0.0f;
056
057                for (float f = 1.0f; f <= octaves; f *= 2)
058                        t += Math.abs(basis.evaluate(f * x, f * y)) / f;
059                return t;
060        }
061
062}