new edge enumeration arrangements; bugfixes

diff --git a/bgl.cpp b/bgl.cpp
index e75918a9d6d8b5799e51caedb2ae39072728b7db..4b06897df09a4ba5e65a903427ab021ce9261cc9 100644 (file)
--- a/bgl.cpp
+++ b/bgl.cpp
@@ -44,28 +44,36 @@ extern "C" {
  */
 
 #define VMASK (YMASK|XMASK)
-#define ESHIFT (YBITS|XBITS)
+#define ESHIFT (YBITS+XBITS)
 
 class Graph { }; // this is a dummy as our graph has no actual representation
 
 using namespace boost;
 
 /*
- * We use the following alternative numbering for iterating over edges:
+ * We iterate over edges in the following order:
  *
- *      ix:        \0   /1
- *                  \  /
- *               ___ 0   __
- *               2    1   3
- *                  /  \
- *                4/   5\
+ *          \#0  /1#
+ *          \  /
+ *       ___ 0   __
+ *      #2    1   #3
+ *          /  \
+ *       #4/  #5\     and finally #6 is V6
  *
  *
- * This numbering permits the order-4 nodes at the strip's edge
- * to have a contiguous edge iterator values 2..5 or 0..3.
+ * This ordering permits the order-4 nodes at the strip's edge
+ * to have a contiguous edge iterator values.  The iterator
+ * starts at #0 which is edge 2 (see mgraph.h), or #2 (edge 3).
  */
-static const int oee_edgemap[V6]=
-  { 2<<ESHIFT, 1<<ESHIFT, 3<<ESHIFT, 2<<ESHIFT, 4<<ESHIFT, 5<<ESHIFT };
+static const int oei_edge_delta[V6]=
+  /*    0       1       2       3       4       5      initial e
+   *   #3      #1      #0      #2      #4      #5      initial ix
+   *   #4      #2      #1      #3      #5      #6      next ix
+   *    4       3       1       0       5      V6      next e
+   */ {
+     4<<ESHIFT, 2<<ESHIFT, -1<<ESHIFT,
+                              -3<<ESHIFT, 1<<ESHIFT, (V6-5)<<ESHIFT
+};
 
 class OutEdgeIterator :
   public iterator_facade<
@@ -73,18 +81,24 @@ class OutEdgeIterator :
     int const,
     forward_traversal_tag
 > {
-  int v, ix, f;
-  
-  void setf() { f= v | oee_edgemap[ix]; }
+  int f;
  public:
-  void increment() { ix++; setf(); }
-  bool equal(OutEdgeIterator const& other) const { return ix == other.ix; }
+  void increment() {
+    //printf("incrementing f=%03x..",f);
+    f += oei_edge_delta[f>>ESHIFT];
+    //printf("%03x\n",f);
+  }
+  bool equal(OutEdgeIterator const& other) const { return f == other.f; }
   int const& dereference() const { return f; }
   OutEdgeIterator() { }
-  OutEdgeIterator(int _v, int _ix) : v(_v), ix(_ix) { setf(); }
+  OutEdgeIterator(int _f) : f(_f) { }
+  OutEdgeIterator(int v, int e) : f(e<<ESHIFT | v) {
+    //printf("constructed v=%x e=%x f=%03x\n",v,e,f);
+  }
 
-  static int voe_min(int _v) { return _v & YMASK ? 0 : 2; }
-  static int voe_max(int _v) { return ~_v & YMASK ? V6 : 4; }
+  static int voe_min(int _v) { return (_v & YMASK) ? 2 : 3; }
+  static int voe_max(int _v) { return (~_v & YMASK) ? V6 : 4; }
+  static int voe_degree(int _v) { return (_v & YMASK | ~_v & YMASK) ? 4 : V6; }
 };
  
 typedef counting_iterator<int> VertexIterator;
@@ -129,7 +143,7 @@ namespace boost {
                          OutEdgeIterator(v, OutEdgeIterator::voe_max(v)));
   }
   inline unsigned out_degree(int v, const Graph&) {
-    return OutEdgeIterator::voe_max(v) - OutEdgeIterator::voe_min(v);
+    return OutEdgeIterator::voe_degree(v);
   }
 
   // Concept VertexListGraph:

diff --git a/energy.c b/energy.c
index b2ee07339b2401b610e728065b423421787f26fb..89b56e219871247896580f5f266f0dc1515876bf 100644 (file)
--- a/energy.c
+++ b/energy.c
@@ -247,8 +247,8 @@ static double edgewise_vertex_displacement_cost(const Vertices vertices) {
   FOR_EDGE(pi,e,qi) {
     ri= EDGE_END2(pi,(e+1)%V6); if (ri<0) continue;
     si= EDGE_END2(pi,(e+5)%V6); if (si<0) continue;
-    assert(ri == EDGE_END2(qi,(e+2)%V6));
-    assert(si == EDGE_END2(qi,(e+4)%V6));
+    /* assert(ri == EDGE_END2(qi,(e+2)%V6)); */
+    /* assert(si == EDGE_END2(qi,(e+4)%V6)); */
     
     K m[k]= (vertices[pi][k] + vertices[qi][k]) * 0.5;
     K mprime[k]= (vertices[ri][k] + vertices[si][k]) * 0.5;