checkpoint

darcs-hash:20071202030301-5007d-35faf934f46cc0b2a4a9a65f6402b959a51ee571.gz

diff --git a/src/Geom.java b/src/Geom.java
index 316e334..445c896 100644 (file)
--- a/src/Geom.java
+++ b/src/Geom.java
@@ -188,6 +188,21 @@ public class Geom implements Iterable<Geom.T> {
         public String toString() { return "<"+x+","+y+","+z+">"; }
     }
 
+    public class BindingGroup {
+        public HashSet<E> es = new HashSet<E>();
+        public BindingGroup() { }
+        public merge(E e) {
+            if (e.bg != null) merge(e.bg);
+            else { es.add(e); e.bg = this; }
+        }
+        public merge(BindingGroup bg) {
+            for(E e : bg.es) {
+                e.bg = this;
+                this.bg.add(e);
+            }
+        }
+    }
+
     /** [UNIQUE] an edge */
     public final class E {
         public final P p1, p2;
@@ -197,17 +212,23 @@ public class Geom implements Iterable<Geom.T> {
         E pair;  // partner half-edge
 
 
-        public E bound_to = this;
+        public BindingGroup bg = null;
 
         public void bind(E e) { bind(e, new M()); }
         public void bind(E e, M m) {
-            E old = this.bound_to;
-            this.bound_to = e.bound_to;
-            e.bound_to = old;
+            if (e.bg != null) e.bg.merge(this);
+            else if (bg != null) bg.merge(e);
+            else {
+                bg = new BindingGroup();
+                bg.merge(this);
+                bg.merge(e);
+            }
         }
 
         public void dobind() {
-            for(E ex = bound_to; ex != this; ex = ex.bound_to) {
+            if (bg==null) return;
+            for(E ex : bg.es) {
+                if (ex==this) continue;
                 p1.bind(ex.p1);
                 p2.bind(ex.p2);
             }