1 /** 2 * Copyright (c) 2011, Novyon Events 3 * 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * - Redistributions of source code must retain the above copyright notice, this 10 * list of conditions and the following disclaimer. 11 * 12 * - Redistributions in binary form must reproduce the above copyright notice, 13 * this list of conditions and the following disclaimer in the documentation 14 * and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 25 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 26 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * @author Anthyon 29 */ 30 package com.jme3.terrain.noise.modulator; 31 32 import java.util.HashMap; 33 import java.util.Map; 34 35 import com.jme3.terrain.noise.ShaderUtils; 36 37 public class CatRom2 implements Modulator { 38 39 private int sampleRate = 100; 40 41 private final float[] table; 42 43 private static Map<Integer, CatRom2> instances = new HashMap<Integer, CatRom2>(); 44 CatRom2(final int sampleRate)45 public CatRom2(final int sampleRate) { 46 this.sampleRate = sampleRate; 47 this.table = new float[4 * sampleRate + 1]; 48 for (int i = 0; i < 4 * sampleRate + 1; i++) { 49 float x = i / (float) sampleRate; 50 x = (float) Math.sqrt(x); 51 if (x < 1) { 52 this.table[i] = 0.5f * (2 + x * x * (-5 + x * 3)); 53 } else { 54 this.table[i] = 0.5f * (4 + x * (-8 + x * (5 - x))); 55 } 56 } 57 } 58 getInstance(final int sampleRate)59 public static CatRom2 getInstance(final int sampleRate) { 60 if (!CatRom2.instances.containsKey(sampleRate)) { 61 CatRom2.instances.put(sampleRate, new CatRom2(sampleRate)); 62 } 63 return CatRom2.instances.get(sampleRate); 64 } 65 66 @Override value(final float... in)67 public float value(final float... in) { 68 if (in[0] >= 4) { 69 return 0; 70 } 71 in[0] = in[0] * this.sampleRate + 0.5f; 72 int i = ShaderUtils.floor(in[0]); 73 if (i >= 4 * this.sampleRate + 1) { 74 return 0; 75 } 76 return this.table[i]; 77 } 78 } 79