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

   1 package edu.berkeley.qfat.geom;
   2 import javax.media.opengl.*;
   3 import java.util.*;
   4 import edu.berkeley.qfat.Mesh;
   5
   6 public abstract class HasBindingGroup {
   7
   8     public BindingGroup bindingGroup;
   9
  10     // know:      self   = bindingGroup[self] * master
  11     // know:      other  = other.bindingGroup[other] * other.bindingGroup.master
  12     // want:      self   = bindingMatrix * other
  13     // therefore: master = bindingGroup[self]^-1 * bindingMatrix * other
  14     // therefore:        = bindingGroup[self]^-1 * bindingMatrix * other.bindingGroup[other] * other.bindingGroup.master
  15     public void bindTo(Matrix bindingMatrix, HasBindingGroup other) {
  16         if (bindingGroup == null) bindingGroup = new BindingGroup(this);
  17         if (other.bindingGroup == null) other.bindingGroup = new BindingGroup(other);
  18
  19         if (other.bindingGroup == this.bindingGroup) {
  20             if (getBindingMatrix(other).equals(bindingMatrix))
  21                 return;
  22             /*
  23             if (this instanceof Mesh.E)
  24                 throw new Error("rebind attempt: "+this+" and "+other+" with "
  25                                 + bindingMatrix
  26                                 + "; expected "
  27                                 + getBindingMatrix(other));
  28             */
  29             setConstraint(bindingMatrix);
  30             /*
  31               System.err.println("WARNING: discarding rebind attempt: "+this+" and "+other+m);
  32             */
  33             //" with "
  34             //+ bindingMatrix
  35             //+ "; expected "
  36             //+ getBindingMatrix(other));
  37             return;
  38         }
  39
  40
  41         bindingMatrix =
  42             getBindingMatrix().inverse()
  43             .times(bindingMatrix)
  44             .times(other.getBindingMatrix());
  45         other.bindingGroup.merge(bindingGroup, bindingMatrix);
  46     }
  47
  48     public int bindingGroupSize() {
  49         if (bindingGroup == null) return 1;
  50         return bindingGroup.size();
  51     }
  52
  53
  54     public Matrix getBindingMatrix() {
  55         if (bindingGroup==null) return Matrix.ONE;
  56         return bindingGroup.getMatrix(this);
  57     }
  58
  59     public Matrix getBindingMatrix(HasBindingGroup other) {
  60         if (other==this) return Matrix.ONE;
  61         return bindingGroup.getMatrix(this, other);
  62     }
  63
  64     public HasBindingGroup getMaster() {
  65         if (bindingGroup==null) return this;
  66         return bindingGroup.getMaster();
  67     }
  68
  69     public Matrix getConstraint() {
  70         if (bindingGroup==null) return Matrix.ONE;
  71         Matrix v = getBindingMatrix(getMaster());
  72         return v.inverse().times(bindingGroup.krank).times(v);
  73     }
  74     public void setConstraint(Matrix m) {
  75         if (bindingGroup==null) bindingGroup = new BindingGroup(this);
  76         Matrix v = getBindingMatrix(getMaster());
  77         bindingGroup.krank = bindingGroup.krank.times(v.inverse().times(m).times(v));
  78     }
  79
  80     public void unbind() {
  81         if (bindingGroup==null) return;
  82         bindingGroup.unbind(this);
  83         bindingGroup = null;
  84         bindingGroupChanged(bindingGroup);
  85     }
  86
  87     public boolean isBoundTo(HasBindingGroup t) {
  88         return t==this || (bindingGroup!=null && bindingGroup.contains(t));
  89     }
  90
  91     public Iterable getBoundPeers() {
  92         if (bindingGroup==null) bindingGroup = new BindingGroup(this);
  93         return bindingGroup;
  94     }
  95     public void bindingGroupChanged(BindingGroup newBindingGroup) { }
  96 }