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

   1 package org.simantics.g3d.shape;\r
   2 \r
   3 import java.util.ArrayList;\r
   4 import java.util.List;\r
   5 \r
   6 import javax.vecmath.AxisAngle4d;\r
   7 import javax.vecmath.Vector3d;\r
   8 \r
   9 import org.simantics.g3d.math.MathTools;\r
  10 \r
  11 public class Sphere {\r
  12 \r
  13         public static Mesh create(double radius, int s, int p) {\r
  14                 if (s < 3 || p < 3 || radius < MathTools.NEAR_ZERO)\r
  15                         throw new IllegalArgumentException();\r
  16                 List<Vector3d> vertices = new ArrayList<Vector3d>((s-2)*p + 2);\r
  17                 List<Vector3d> normals = new ArrayList<Vector3d>(vertices.size());\r
  18                 List<Integer> indices = new ArrayList<Integer>(((s-3)*p*2 + p * 2)*3);\r
  19                 Vector3d v = new Vector3d(0.0,-radius,0.0);\r
  20                 Vector3d vp = new Vector3d();\r
  21                 for (int ip = 0; ip < p; ip++) {\r
  22                         if (ip == 0) {\r
  23                                 vertices.add(new Vector3d(0.0,-radius,0.0));\r
  24                         } else if (ip == p - 1) {\r
  25                                 vertices.add(new Vector3d(0.0, radius,0.0));\r
  26                                 int off = 1 + (ip-2)*s;\r
  27                                 for (int is = 0; is < s; is++) {\r
  28                                         indices.add(vertices.size() - 1);\r
  29                                         indices.add(is+off);\r
  30                                         if (is < s -1)\r
  31                                                 indices.add(is+off+1);\r
  32                                         else\r
  33                                                 indices.add(off);\r
  34                                         \r
  35                                         \r
  36                                 }\r
  37                         } else {\r
  38                                 AxisAngle4d aa = new AxisAngle4d(1, 0, 0, ((double)ip/(double)(p-1))*Math.PI);\r
  39                                 MathTools.rotate(MathTools.getQuat(aa), v, vp);\r
  40                                 for (int is = 0; is < s; is++) {\r
  41                                         aa = new AxisAngle4d(0, 1, 0, ((double)is/(double)s)*Math.PI*2);\r
  42                                         Vector3d vs = new Vector3d();\r
  43                                         MathTools.rotate(MathTools.getQuat(aa), vp, vs);\r
  44                                         vertices.add(vs);\r
  45                                 }\r
  46                                 if (ip == 1) {\r
  47                                         for (int is = 0; is < s; is++) {\r
  48                                                 indices.add(0);\r
  49                                                 if (is < s -1)\r
  50                                                         indices.add(is+2);\r
  51                                                 else\r
  52                                                         indices.add(1);\r
  53                                                 indices.add(is+1);\r
  54                                         }\r
  55                                 } else {\r
  56                                         int off = 1 + (ip-1)*s;\r
  57                                         for (int is = 0; is < s-1; is++) {\r
  58                                                 indices.add(off + is - s);\r
  59                                                 indices.add(off + is+1);\r
  60                                                 indices.add(off + is);\r
  61                                                 \r
  62                                                 \r
  63                                                 indices.add(off + is - s);\r
  64                                                 indices.add(off + is + 1 - s);\r
  65                                                 indices.add(off + is + 1);\r
  66                                                 \r
  67                                         }\r
  68                                         indices.add(off - 1);\r
  69                                         indices.add(off);\r
  70                                         indices.add(off + s - 1);\r
  71                                         \r
  72                                         indices.add(off -1);\r
  73                                         indices.add(off - s);\r
  74                                         indices.add(off);\r
  75                                         \r
  76                                 }\r
  77                         }\r
  78                 }\r
  79                 for (int i = 0; i < vertices.size(); i++) {\r
  80                         Vector3d n = new Vector3d(vertices.get(i));\r
  81                         n.normalize();\r
  82                         normals.add(n);\r
  83                 }\r
  84                 \r
  85                 return new Mesh(vertices,normals,indices);\r
  86                 \r
  87         }\r
  88         \r
  89         public static void main(String arg[]) {\r
  90                 Mesh s1 = create(1.0, 3, 3);\r
  91                 Mesh s2 = create(1.0, 4, 4);\r
  92                 System.out.println("debug " + s1 + " " + s2);\r
  93         }\r
  94 }\r