src/edu/berkeley/qfat/geom/HasBindingGroup.java

   1 package edu.berkeley.qfat.geom;
   2 import javax.media.opengl.*;
   3 import java.util.*;
   4
   5 public abstract class HasBindingGroup {
   6
   7     public BindingGroup bindingGroup;
   8
   9     // know:      self   = bindingGroup[self] * master
  10     // know:      other  = other.bindingGroup[other] * other.bindingGroup.master
  11     // want:      self   = bindingMatrix * other
  12     // therefore: master = bindingGroup[self]^-1 * bindingMatrix * other
  13     // therefore:        = bindingGroup[self]^-1 * bindingMatrix * other.bindingGroup[other] * other.bindingGroup.master
  14     public void bindTo(Matrix bindingMatrix, HasBindingGroup other) {
  15         if (bindingGroup == null) bindingGroup = new BindingGroup(this);
  16         if (other.bindingGroup == null) other.bindingGroup = new BindingGroup(other);
  17
  18         if (other.bindingGroup == this.bindingGroup) {
  19             if (getBindingMatrix(other).equals(bindingMatrix))
  20                 return;
  21             /*
  22             throw new Error("rebind attempt: "+this+" and "+other+" with "
  23                             + bindingMatrix
  24                             + "; expected "
  25                             + getBindingMatrix(other));
  26             */
  27             Matrix vom = other.getBindingMatrix(bindingGroup.getMaster());
  28             Matrix v2 = bindingMatrix;
  29             Matrix v3 = getBindingMatrix(other);
  30             Matrix m = vom.inverse().times(v2.inverse()).times(v3).times(vom);
  31             bindingGroup.krank = bindingGroup.krank.times(m);
  32             /*
  33               System.err.println("WARNING: discarding rebind attempt: "+this+" and "+other+m);
  34             */
  35             //" with "
  36             //+ bindingMatrix
  37             //+ "; expected "
  38             //+ getBindingMatrix(other));
  39             return;
  40         }
  41
  42
  43         bindingMatrix =
  44             getBindingMatrix().inverse()
  45             .times(bindingMatrix)
  46             .times(other.getBindingMatrix());
  47         other.bindingGroup.merge(bindingGroup, bindingMatrix);
  48     }
  49
  50     public int bindingGroupSize() {
  51         if (bindingGroup == null) return 1;
  52         return bindingGroup.size();
  53     }
  54
  55
  56     public Matrix getBindingMatrix() {
  57         if (bindingGroup==null) return Matrix.ONE;
  58         return bindingGroup.getMatrix(this);
  59     }
  60
  61     public Matrix getBindingMatrix(HasBindingGroup other) {
  62         if (other==this) return Matrix.ONE;
  63         return bindingGroup.getMatrix(this, other);
  64     }
  65
  66     public HasBindingGroup getMaster() {
  67         if (bindingGroup==null) return this;
  68         return bindingGroup.getMaster();
  69     }
  70
  71     public void unbind() {
  72         if (bindingGroup==null) return;
  73         bindingGroup.unbind(this);
  74         bindingGroup = null;
  75         bindingGroupChanged(bindingGroup);
  76     }
  77
  78     public boolean isBoundTo(HasBindingGroup t) {
  79         return t==this || (bindingGroup!=null && bindingGroup.contains(t));
  80     }
  81
  82     public Iterable getBoundPeers() {
  83         if (bindingGroup==null) bindingGroup = new BindingGroup(this);
  84         return bindingGroup;
  85     }
  86     public void bindingGroupChanged(BindingGroup newBindingGroup) { }
  87 }