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     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             System.err.println("WARNING: discarding rebind attempt: "+this+" and "+other+" with "
  28                                + bindingMatrix
  29                                + "; expected "
  30                                + getBindingMatrix(other));
  31             return;
  32         }
  33
  34         bindingMatrix =
  35             getBindingMatrix().inverse()
  36             .times(bindingMatrix)
  37             .times(other.getBindingMatrix());
  38         other.bindingGroup.merge(bindingGroup, bindingMatrix);
  39     }
  40
  41     public int bindingGroupSize() {
  42         if (bindingGroup == null) return 1;
  43         return bindingGroup.size();
  44     }
  45
  46
  47     public Matrix getBindingMatrix() {
  48         if (bindingGroup==null) return Matrix.ONE;
  49         return bindingGroup.getMatrix(this);
  50     }
  51
  52     public Matrix getBindingMatrix(HasBindingGroup other) {
  53         if (other==this) return Matrix.ONE;
  54         return bindingGroup.getMatrix(this, other);
  55     }
  56
  57     public HasBindingGroup getMaster() {
  58         if (bindingGroup==null) return this;
  59         return bindingGroup.getMaster();
  60     }
  61
  62     public void unbind() {
  63         if (bindingGroup==null) return;
  64         bindingGroup.unbind(this);
  65         bindingGroup = null;
  66         bindingGroupChanged(bindingGroup);
  67     }
  68
  69     public boolean isBoundTo(HasBindingGroup t) {
  70         return t==this || (bindingGroup!=null && bindingGroup.contains(t));
  71     }
  72
  73     public Iterable getBoundPeers() {
  74         if (bindingGroup==null) bindingGroup = new BindingGroup(this);
  75         return bindingGroup;
  76     }
  77     public void bindingGroupChanged(BindingGroup newBindingGroup) { }
  78 }