1 /* 2 * Copyright (c) 2009-2012 jMonkeyEngine 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: 8 * 9 * * Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 12 * * Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * * Neither the name of 'jMonkeyEngine' nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 27 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 28 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 29 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 30 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 // $Id: PQTorus.java 4131 2009-03-19 20:15:28Z blaine.dev $ 34 package com.jme3.scene.shape; 35 36 import com.jme3.export.InputCapsule; 37 import com.jme3.export.JmeExporter; 38 import com.jme3.export.JmeImporter; 39 import com.jme3.export.OutputCapsule; 40 import com.jme3.math.FastMath; 41 import com.jme3.math.Vector3f; 42 import com.jme3.scene.Mesh; 43 import com.jme3.scene.VertexBuffer.Type; 44 import static com.jme3.util.BufferUtils.*; 45 import java.io.IOException; 46 import java.nio.FloatBuffer; 47 import java.nio.ShortBuffer; 48 49 /** 50 * A parameterized torus, also known as a <em>pq</em> torus. 51 * 52 * @author Joshua Slack, Eric Woroshow 53 * @version $Revision: 4131 $, $Date: 2009-03-19 16:15:28 -0400 (Thu, 19 Mar 2009) $ 54 */ 55 public class PQTorus extends Mesh { 56 57 private float p, q; 58 59 private float radius, width; 60 61 private int steps, radialSamples; 62 63 public PQTorus() { 64 } 65 66 /** 67 * Creates a parameterized torus. 68 * <p> 69 * Steps and radialSamples are both degree of accuracy values. 70 * 71 * @param p the x/z oscillation. 72 * @param q the y oscillation. 73 * @param radius the radius of the PQTorus. 74 * @param width the width of the torus. 75 * @param steps the steps along the torus. 76 * @param radialSamples radial samples for the torus. 77 */ 78 public PQTorus(float p, float q, float radius, float width, 79 int steps, int radialSamples) { 80 super(); 81 updateGeometry(p, q, radius, width, steps, radialSamples); 82 } 83 84 public float getP() { 85 return p; 86 } 87 88 public float getQ() { 89 return q; 90 } 91 92 public int getRadialSamples() { 93 return radialSamples; 94 } 95 96 public float getRadius() { 97 return radius; 98 } 99 100 public int getSteps() { 101 return steps; 102 } 103 104 public float getWidth() { 105 return width; 106 } 107 108 public void read(JmeImporter e) throws IOException { 109 super.read(e); 110 InputCapsule capsule = e.getCapsule(this); 111 p = capsule.readFloat("p", 0); 112 q = capsule.readFloat("q", 0); 113 radius = capsule.readFloat("radius", 0); 114 width = capsule.readFloat("width", 0); 115 steps = capsule.readInt("steps", 0); 116 radialSamples = capsule.readInt("radialSamples", 0); 117 } 118 119 /** 120 * Rebuilds this torus based on a new set of parameters. 121 * 122 * @param p the x/z oscillation. 123 * @param q the y oscillation. 124 * @param radius the radius of the PQTorus. 125 * @param width the width of the torus. 126 * @param steps the steps along the torus. 127 * @param radialSamples radial samples for the torus. 128 */ 129 public void updateGeometry(float p, float q, float radius, float width, int steps, int radialSamples) { 130 this.p = p; 131 this.q = q; 132 this.radius = radius; 133 this.width = width; 134 this.steps = steps; 135 this.radialSamples = radialSamples; 136 137 final float thetaStep = (FastMath.TWO_PI / steps); 138 final float betaStep = (FastMath.TWO_PI / radialSamples); 139 Vector3f[] torusPoints = new Vector3f[steps]; 140 141 // Allocate all of the required buffers 142 int vertCount = radialSamples * steps; 143 144 FloatBuffer fpb = createVector3Buffer(vertCount); 145 FloatBuffer fnb = createVector3Buffer(vertCount); 146 FloatBuffer ftb = createVector2Buffer(vertCount); 147 148 Vector3f pointB = new Vector3f(), T = new Vector3f(), N = new Vector3f(), B = new Vector3f(); 149 Vector3f tempNorm = new Vector3f(); 150 float r, x, y, z, theta = 0.0f, beta = 0.0f; 151 int nvertex = 0; 152 153 // Move along the length of the pq torus 154 for (int i = 0; i < steps; i++) { 155 theta += thetaStep; 156 float circleFraction = ((float) i) / (float) steps; 157 158 // Find the point on the torus 159 r = (0.5f * (2.0f + FastMath.sin(q * theta)) * radius); 160 x = (r * FastMath.cos(p * theta) * radius); 161 y = (r * FastMath.sin(p * theta) * radius); 162 z = (r * FastMath.cos(q * theta) * radius); 163 torusPoints[i] = new Vector3f(x, y, z); 164 165 // Now find a point slightly farther along the torus 166 r = (0.5f * (2.0f + FastMath.sin(q * (theta + 0.01f))) * radius); 167 x = (r * FastMath.cos(p * (theta + 0.01f)) * radius); 168 y = (r * FastMath.sin(p * (theta + 0.01f)) * radius); 169 z = (r * FastMath.cos(q * (theta + 0.01f)) * radius); 170 pointB = new Vector3f(x, y, z); 171 172 // Approximate the Frenet Frame 173 T = pointB.subtract(torusPoints[i]); 174 N = torusPoints[i].add(pointB); 175 B = T.cross(N); 176 N = B.cross(T); 177 178 // Normalise the two vectors and then use them to create an oriented circle 179 N = N.normalize(); 180 B = B.normalize(); 181 beta = 0.0f; 182 for (int j = 0; j < radialSamples; j++, nvertex++) { 183 beta += betaStep; 184 float cx = FastMath.cos(beta) * width; 185 float cy = FastMath.sin(beta) * width; 186 float radialFraction = ((float) j) / radialSamples; 187 tempNorm.x = (cx * N.x + cy * B.x); 188 tempNorm.y = (cx * N.y + cy * B.y); 189 tempNorm.z = (cx * N.z + cy * B.z); 190 fnb.put(tempNorm.x).put(tempNorm.y).put(tempNorm.z); 191 tempNorm.addLocal(torusPoints[i]); 192 fpb.put(tempNorm.x).put(tempNorm.y).put(tempNorm.z); 193 ftb.put(radialFraction).put(circleFraction); 194 } 195 } 196 197 // Update the indices data 198 ShortBuffer sib = createShortBuffer(6 * vertCount); 199 for (int i = 0; i < vertCount; i++) { 200 sib.put(new short[] { 201 (short)(i), 202 (short)(i - radialSamples), 203 (short)(i + 1), 204 (short)(i + 1), 205 (short)(i - radialSamples), 206 (short)(i - radialSamples + 1) 207 }); 208 } 209 for (int i = 0, len = sib.capacity(); i < len; i++) { 210 int ind = sib.get(i); 211 if (ind < 0) { 212 ind += vertCount; 213 sib.put(i, (short) ind); 214 } else if (ind >= vertCount) { 215 ind -= vertCount; 216 sib.put(i, (short) ind); 217 } 218 } 219 sib.rewind(); 220 221 setBuffer(Type.Position, 3, fpb); 222 setBuffer(Type.Normal, 3, fnb); 223 setBuffer(Type.TexCoord, 2, ftb); 224 setBuffer(Type.Index, 3, sib); 225 } 226 227 @Override 228 public void write(JmeExporter e) throws IOException { 229 super.write(e); 230 OutputCapsule capsule = e.getCapsule(this); 231 capsule.write(p, "p", 0); 232 capsule.write(q, "q", 0); 233 capsule.write(radius, "radius", 0); 234 capsule.write(width, "width", 0); 235 capsule.write(steps, "steps", 0); 236 capsule.write(radialSamples, "radialSamples", 0); 237 } 238 239 }
