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.filter; 31 32 import java.nio.FloatBuffer; 33 34 import com.jme3.terrain.noise.Basis; 35 36 public class HydraulicErodeFilter extends AbstractFilter { 37 38 private Basis waterMap; 39 private Basis sedimentMap; 40 private float Kr; 41 private float Ks; 42 private float Ke; 43 private float Kc; 44 private float T; 45 setKc(float kc)46 public void setKc(float kc) { 47 this.Kc = kc; 48 } 49 setKe(float ke)50 public void setKe(float ke) { 51 this.Ke = ke; 52 } 53 setKr(float kr)54 public void setKr(float kr) { 55 this.Kr = kr; 56 } 57 setKs(float ks)58 public void setKs(float ks) { 59 this.Ks = ks; 60 } 61 setSedimentMap(Basis sedimentMap)62 public void setSedimentMap(Basis sedimentMap) { 63 this.sedimentMap = sedimentMap; 64 } 65 setT(float t)66 public void setT(float t) { 67 this.T = t; 68 } 69 setWaterMap(Basis waterMap)70 public void setWaterMap(Basis waterMap) { 71 this.waterMap = waterMap; 72 } 73 74 @Override getMargin(int size, int margin)75 public int getMargin(int size, int margin) { 76 return super.getMargin(size, margin) + 1; 77 } 78 79 @Override filter(float sx, float sy, float base, FloatBuffer buffer, int workSize)80 public FloatBuffer filter(float sx, float sy, float base, FloatBuffer buffer, int workSize) { 81 float[] ga = buffer.array(); 82 // float[] wa = this.waterMap.getBuffer(sx, sy, base, workSize).array(); 83 // float[] sa = this.sedimentMap.getBuffer(sx, sy, base, 84 // workSize).array(); 85 float[] wt = new float[workSize * workSize]; 86 float[] st = new float[workSize * workSize]; 87 88 int[] idxrel = { -workSize - 1, -workSize + 1, workSize - 1, workSize + 1 }; 89 90 // step 1. water arrives and step 2. captures material 91 for (int y = 0; y < workSize; y++) { 92 for (int x = 0; x < workSize; x++) { 93 int idx = y * workSize + x; 94 float wtemp = this.Kr; // * wa[idx]; 95 float stemp = this.Ks; // * sa[idx]; 96 if (wtemp > 0) { 97 wt[idx] += wtemp; 98 if (stemp > 0) { 99 ga[idx] -= stemp * wt[idx]; 100 st[idx] += stemp * wt[idx]; 101 } 102 } 103 104 // step 3. water is transported to it's neighbours 105 float a = ga[idx] + wt[idx]; 106 // float[] aj = new float[idxrel.length]; 107 float amax = 0; 108 int amaxidx = -1; 109 float ac = 0; 110 float dtotal = 0; 111 112 for (int j = 0; j < idxrel.length; j++) { 113 if (idx + idxrel[j] > 0 && idx + idxrel[j] < workSize) { 114 float at = ga[idx + idxrel[j]] + wt[idx + idxrel[j]]; 115 if (a - at > a - amax) { 116 dtotal += at; 117 amax = at; 118 amaxidx = j; 119 ac++; 120 } 121 } 122 } 123 124 float aa = (dtotal + a) / (ac + 1); 125 // for (int j = 0; j < idxrel.length; j++) { 126 // if (idx + idxrel[j] > 0 && idx + idxrel[j] < workSize && a - 127 // aj[j] > 0) { 128 if (amaxidx > -1) { 129 float dwj = Math.min(wt[idx], a - aa) * (a - amax) / dtotal; 130 float dsj = st[idx] * dwj / wt[idx]; 131 wt[idx] -= dwj; 132 st[idx] -= dsj; 133 wt[idx + idxrel[amaxidx]] += dwj; 134 st[idx + idxrel[amaxidx]] += dsj; 135 } 136 // } 137 138 // step 4. water evaporates and deposits material 139 wt[idx] = wt[idx] * (1 - this.Ke); 140 if (wt[idx] < this.T) { 141 wt[idx] = 0; 142 } 143 float smax = this.Kc * wt[idx]; 144 if (st[idx] > smax) { 145 ga[idx] += st[idx] - smax; 146 st[idx] -= st[idx] - smax; 147 } 148 } 149 } 150 151 return buffer; 152 } 153 154 } 155