org.simantics.g3d/src/org/simantics/g3d/shape/Cone.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012, 2013 Association for Decentralized Information Management in
   3  * Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.g3d.shape;
  13
  14 import java.util.ArrayList;
  15 import java.util.List;
  16
  17 import javax.vecmath.AxisAngle4d;
  18 import javax.vecmath.Vector3d;
  19
  20 import org.simantics.g3d.math.MathTools;
  21
  22 public class Cone {
  23
  24         public static Mesh create(double radius, int s) {
  25                 if (s < 3 || radius < MathTools.NEAR_ZERO)
  26                         throw new IllegalArgumentException();
  27                 List<Vector3d> vertices = new ArrayList<Vector3d>(s+2);
  28                 List<Vector3d> normals = new ArrayList<Vector3d>(vertices.size());
  29                 List<Integer> indices = new ArrayList<Integer>();
  30
  31                 vertices.add(new Vector3d(0.0,0.0,0.0));
  32                 normals.add(new Vector3d(0.0,-1.0,0.0));
  33                 vertices.add(new Vector3d(0.0,radius*2.0,0.0));
  34                 normals.add(new Vector3d(0.0,1.0,0.0));
  35
  36                 Vector3d v = new Vector3d(radius,0,0);
  37                 for (int i = 0; i < s; i++) {
  38                         AxisAngle4d aa = new AxisAngle4d(0,1,0,((double)i/(double)s)*Math.PI * 2);
  39                         Vector3d t = new Vector3d();
  40                         MathTools.rotate(MathTools.getQuat(aa), v, t);
  41                         vertices.add(t);
  42                         Vector3d n = new Vector3d(t);
  43                         n.normalize();
  44                         normals.add(n);
  45                 }
  46
  47                 for (int i = 0; i < s; i++) {
  48                         indices.add(0);
  49
  50                         if (i < s - 1)
  51                                 indices.add(i + 3);
  52                         else
  53                                 indices.add(2);
  54                         indices.add(i + 2);
  55                 }
  56
  57                 for (int i = 0; i < s; i++) {
  58                         indices.add(1);
  59                         indices.add(i + 2);
  60                         if (i < s - 1)
  61                                 indices.add(i + 3);
  62                         else
  63                                 indices.add(2);
  64
  65                 }
  66                 return Mesh.create(vertices,normals,indices);
  67
  68         }
  69
  70         public static void main(String arg[]) {
  71                 Mesh s1 = create(1.0, 3);
  72                 Mesh s2 = create(1.0, 4);
  73                 System.out.println("debug " + s1 + "\n" + s2);
  74         }
  75 }