Updated libs from the Adaptagrams project: libavoid, libcola and libvspc; changed the code to match the new API

Signed-off-by: Sylvain Chiron <chironsylvain@orange.fr>

1 files changed, 1095 insertions, 336 deletions

diff --git a/src/libavoid/makepath.cpp b/src/libavoid/makepath.cpp
index 774e0d7f5..329d5974d 100644
--- a/src/libavoid/makepath.cpp
+++ b/src/libavoid/makepath.cpp
@@ -3,7 +3,7 @@
  *
  * libavoid - Fast, Incremental, Object-avoiding Line Router
  *
- * Copyright (C) 2004-2009  Monash University
+ * Copyright (C) 2004-2014  Monash University
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -19,27 +19,31 @@
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  
  *
- * Author(s):   Michael Wybrow <mjwybrow@users.sourceforge.net>
+ * Author(s):  Michael Wybrow
 */
 
+// For M_PI.
+// This should be first include for MSVC.
+#define _USE_MATH_DEFINES
+#include <cmath>
 
 #include <algorithm>
 #include <vector>
 #include <climits>
-#define _USE_MATH_DEFINES
-#include <cmath>
+#include <cfloat>
 
-#include "libavoid/vertices.h"
 #include "libavoid/makepath.h"
+#include "libavoid/vertices.h"
 #include "libavoid/geometry.h"
 #include "libavoid/connector.h"
+#include "libavoid/viscluster.h"
 #include "libavoid/graph.h"
 #include "libavoid/router.h"
 #include "libavoid/debug.h"
 #include "libavoid/assertions.h"
-#ifdef ASTAR_DEBUG
-  #include <SDL_gfxPrimitives.h>
-#endif
+#include "libavoid/debughandler.h"
+
+//#define ESTIMATED_COST_DEBUG
 
 namespace Avoid {
 
@@ -51,8 +55,8 @@ class ANode
         double h;        // Heuristic
         double f;        // Formula f = g + h
         
-        int prevIndex;   // Index into DONE for the previous ANode.
-        int timeStamp;   // Timestamp used to determine explaration order of
+        ANode *prevNode; // VertInf for the previous ANode.
+        int timeStamp;   // Time-stamp used to determine exploration order of
                          // seemingly equal paths during orthogonal routing.
 
         ANode(VertInf *vinf, int time)
@@ -60,7 +64,7 @@ class ANode
               g(0),
               h(0),
               f(0),
-              prevIndex(-1),
+              prevNode(NULL),
               timeStamp(time)
         {
         }
@@ -69,37 +73,108 @@ class ANode
               g(0),
               h(0),
               f(0),
-              prevIndex(-1),
+              prevNode(NULL),
               timeStamp(-1)
         {
         }
 };
 
+class AStarPathPrivate
+{
+    public:
+        AStarPathPrivate()
+            : m_available_nodes(),
+              m_available_array_size(0),
+              m_available_array_index(0),
+              m_available_node_index(0)
+        {
+        }
+        ~AStarPathPrivate()
+        {
+            // Free memory
+            for (size_t i = 0; i < m_available_nodes.size(); ++i)
+            {
+                delete[] m_available_nodes[i];
+            }
+        }
+        // Returns a pointer to an ANode for aStar search, but allocates
+        // these in blocks 
+        ANode *newANode(const ANode& node, const bool addToPending = true)
+        {
+            const size_t blockSize = 5000;
+            if ((m_available_array_index + 1 > m_available_array_size) ||
+                    (m_available_node_index >= blockSize))
+            {
+                m_available_nodes.push_back(new ANode[blockSize]);
+                ++m_available_array_size;
+                m_available_node_index = 0;
+                m_available_array_index = m_available_array_size - 1;
+            }
+            
+            ANode *nodes = m_available_nodes[m_available_array_index];
+            ANode *newNode = &(nodes[m_available_node_index++]);
+            *newNode = node;
+            if (addToPending)
+            {
+                node.inf->aStarPendingNodes.push_back(newNode);
+            }
+            return newNode;
+        }
+        void search(ConnRef *lineRef, VertInf *src, VertInf *tar, 
+                VertInf *start);
+
+    private:
+        void determineEndPointLocation(double dist, VertInf *start,
+                VertInf *target, VertInf *other, int level);
+        double estimatedCost(ConnRef *lineRef, const Point *last,
+                const Point& curr) const;
+
+        std::vector<ANode *> m_available_nodes;
+        size_t m_available_array_size;
+        size_t m_available_array_index;
+        size_t m_available_node_index;
+ 
+        // For determining estimated cost target.
+        std::vector<VertInf *> m_cost_targets;
+        std::vector<unsigned int> m_cost_targets_directions;
+        std::vector<double> m_cost_targets_displacements;
+};
+
+
 
 // This returns the opposite result (>) so that when used with stl::make_heap, 
 // the head node of the heap will be the smallest value, rather than the 
 // largest.  This saves us from having to sort the heap (and then reorder
 // it back into a heap) when getting the next node to examine.  This way we
-// get better complexity -- logarithmic pushs and pops to the heap.
+// get better complexity -- logarithmic pushes and pops to the heap.
 //
-static bool operator<(const ANode &a, const ANode &b)
+class ANodeCmp
+{
+    public:
+    ANodeCmp()
+    {
+    }
+bool operator()(const ANode *a, const ANode *b)
 {
-    if (a.f != b.f)
+    // We need to use an epsilon here since otherwise the multiple addition
+    // of floating point numbers that makes up the 'f' values cause a problem
+    // with routings occasionally being non-deterministic.
+    if (fabs(a->f - b->f) > 0.0000001)
     {
-        return a.f > b.f;
+        return a->f > b->f;
     }
-    if (a.timeStamp != b.timeStamp)
+    if (a->timeStamp != b->timeStamp)
     {
         // Tiebreaker, if two paths have equal cost, then choose the one with
         // the highest timeStamp.  This corresponds to the furthest point
         // explored along the straight-line path.  When exploring we give the
         // directions the following timeStamps; left:1, right:2 and forward:3,
         // then we always try to explore forward first.
-        return a.timeStamp < b.timeStamp;
+        return a->timeStamp < b->timeStamp;
     }
-    COLA_ASSERT(a.prevIndex != b.prevIndex);
-    return a.prevIndex > b.prevIndex;
+    return false;
 }
+};
 
 
 static double Dot(const Point& l, const Point& r)
@@ -135,24 +210,95 @@ static double angleBetween(const Point& p1, const Point& p2, const Point& p3)
 // Construct a temporary Polygon path given several VertInf's for a connector.
 //
 static void constructPolygonPath(Polygon& connRoute, VertInf *inf2, 
-        VertInf *inf3, std::vector<ANode>& done, int inf1Index)
+        VertInf *inf3, ANode *inf1Node)
 {
+    // Don't include colinear points.
+    bool simplified = true;
+
     int routeSize = 2;
-    for (int curr = inf1Index; curr >= 0; curr = done[curr].prevIndex)
+    for (ANode *curr = inf1Node; curr != NULL; curr = curr->prevNode)
     {
         routeSize += 1;
     }
     connRoute.ps.resize(routeSize);
+    int arraySize = routeSize;
     connRoute.ps[routeSize - 1] = inf3->point;
     connRoute.ps[routeSize - 2] = inf2->point;
     routeSize -= 3;
-    for (int curr = inf1Index; curr >= 0; curr = done[curr].prevIndex)
+    for (ANode *curr = inf1Node; curr != NULL; curr = curr->prevNode)
     {
-        connRoute.ps[routeSize] = done[curr].inf->point;
-        routeSize -= 1;
+        // For connection pins, we stop and don't include the fake shape 
+        // center as part of this path.
+        bool isConnectionPin = curr->inf->id.isConnectionPin();
+
+        if (!simplified)
+        {
+            // If this is non-simplified, we don't need to do anything 
+            // clever and can simply add the new point.
+            connRoute.ps[routeSize] = curr->inf->point;
+            routeSize -= 1;
+            
+            if (isConnectionPin)
+            {
+                // Stop at the connection pin.
+                break;
+            }
+            continue;
+        }
+            
+        if ((curr == inf1Node) || 
+                vecDir(curr->inf->point, connRoute.ps[routeSize + 1], 
+                    connRoute.ps[routeSize + 2]) != 0)
+        {
+            // Add new point if this is the earlier than the last segment
+            // and it is not colinear with the other points.  
+            // Note, you can't collapse the 'last' segment with previous 
+            // segments, or if this just intersects another line you risk 
+            // penalising it once for each collapsed line segment.
+            connRoute.ps[routeSize] = curr->inf->point;
+            routeSize -= 1;
+        }
+        else
+        {
+            // The last point is inline with this one, so update it.
+            connRoute.ps[routeSize + 1] = curr->inf->point;
+        }
+            
+        if (isConnectionPin)
+        {
+            // Stop at the connection pin.
+            break;
+        }
+    }
+
+    // If the vector is not filled, move entries to the beginning and 
+    // remove the unused end of the vector.
+    int diff = routeSize + 1;
+    COLA_ASSERT(simplified || (diff == 0));
+    if (diff > 0)
+    {
+        for (int i = diff; i < arraySize; ++i)
+        {
+            connRoute.ps[i - diff] = connRoute.ps[i];
+        }
+        connRoute.ps.resize(connRoute.size() - diff);
     }
 }
 
+// Used to get an indication of if a diffence is positive (1),
+// negative (-1) or no different (0).
+static inline int dimDirection(double difference)
+{
+    if (difference > 0)
+    {
+        return 1;
+    }
+    else if (difference < 0)
+    {
+        return -1;
+    }
+    return 0;
+}
 
 // Given the two points for a new segment of a path (inf2 & inf3)
 // as well as the distance between these points (dist), as well as
@@ -160,17 +306,18 @@ static void constructPolygonPath(Polygon& connRoute, VertInf *inf2,
 // cost associated with this route.
 //
 static double cost(ConnRef *lineRef, const double dist, VertInf *inf2, 
-        VertInf *inf3, std::vector<ANode>& done, int inf1Index)
+        VertInf *inf3, ANode *inf1Node)
 {
-    VertInf *inf1 = (inf1Index >= 0) ?  done[inf1Index].inf : NULL;
+    bool isOrthogonal = (lineRef->routingType() == ConnType_Orthogonal);
+    VertInf *inf1 = (inf1Node) ? inf1Node->inf : NULL;
     double result = dist;
     Polygon connRoute;
 
     Router *router = inf2->_router;
     if (inf1 != NULL)
     {
-        const double angle_penalty = router->routingPenalty(anglePenalty);
-        const double segmt_penalty = router->routingPenalty(segmentPenalty);
+        const double angle_penalty = router->routingParameter(anglePenalty);
+        const double segmt_penalty = router->routingParameter(segmentPenalty);
 
         // This is not the first segment, so there is a bend
         // between it and the last one in the existing path.
@@ -182,7 +329,7 @@ static double cost(ConnRef *lineRef, const double dist, VertInf *inf2,
 
             double rad = M_PI - angleBetween(p1, p2, p3);
 
-            if (rad > 0)
+            if ((rad > 0) && !isOrthogonal)
             {
                 // Make `xval' between 0--10 then take its log so small
                 // angles are not penalised as much as large ones.
@@ -208,55 +355,96 @@ static double cost(ConnRef *lineRef, const double dist, VertInf *inf2,
         }
     }
 
-    if (!router->_inCrossingPenaltyReroutingStage)
-    {
-        // Return here if we ar not in the postprocessing stage 
-        return result;
-    }
-
     const double cluster_crossing_penalty = 
-            router->routingPenalty(clusterCrossingPenalty);
+            router->routingParameter(clusterCrossingPenalty);
     // XXX: Clustered routing doesn't yet work with orthogonal connectors.
     if (router->ClusteredRouting && !router->clusterRefs.empty() &&
-            (cluster_crossing_penalty > 0) && 
-            (lineRef->routingType() != ConnType_Orthogonal))
+            (cluster_crossing_penalty > 0))
     {
         if (connRoute.empty())
         {
-            constructPolygonPath(connRoute, inf2, inf3, done, inf1Index);
+            constructPolygonPath(connRoute, inf2, inf3, inf1Node);
         }
         // There are clusters so do cluster routing.
         for (ClusterRefList::const_iterator cl = router->clusterRefs.begin(); 
                 cl != router->clusterRefs.end(); ++cl)
         {
-            ReferencingPolygon& cBoundary = (*cl)->polygon();
+            Polygon cBoundary = (isOrthogonal) ?
+                    (*cl)->rectangularPolygon() : (*cl)->polygon();
+            if (cBoundary.size() <= 2)
+            {
+                continue;
+            }
             COLA_ASSERT(cBoundary.ps[0] != cBoundary.ps[cBoundary.size() - 1]);
             for (size_t j = 0; j < cBoundary.size(); ++j)
             {
-                // Cluster boundary points should correspond to shape 
-                // vertices and hence already be in the list of vertices.
-                COLA_ASSERT(router->vertices.getVertexByPos(cBoundary.at(j))!=NULL);
+                // Non-orthogonal cluster boundary points should correspond to 
+                // shape vertices and hence already be in the list of vertices.
+                COLA_ASSERT(isOrthogonal || 
+                        router->vertices.getVertexByPos(cBoundary.at(j)));
             }
             
             bool isConn = false;
-            Polygon dynamic_c_boundary(cBoundary);
             Polygon dynamic_conn_route(connRoute);
             const bool finalSegment = (inf3 == lineRef->dst());
-            CrossingsInfoPair crossings = countRealCrossings(
-                    dynamic_c_boundary, isConn, dynamic_conn_route, 
-                    connRoute.size() - 1, true, finalSegment);
-            result += (crossings.first * cluster_crossing_penalty);
+            ConnectorCrossings cross(cBoundary, isConn, dynamic_conn_route);
+            cross.checkForBranchingSegments = true;
+            cross.countForSegment(connRoute.size() - 1, finalSegment);
+            
+            result += (cross.crossingCount * cluster_crossing_penalty);
+        }
+    }
+    
+    // This penalty penalises route segments that head in a direction opposite
+    // of the direction(s) toward the target point.  
+    const double reversePenalty = router->routingParameter(
+            reverseDirectionPenalty);
+    if (reversePenalty)
+    {
+        // X and Y direction of destination from source point.
+        const Point& srcPoint = lineRef->src()->point;
+        const Point& dstPoint = lineRef->dst()->point;
+        int xDir = dimDirection(dstPoint.x - srcPoint.x);
+        int yDir = dimDirection(dstPoint.y - srcPoint.y);
+        
+        bool doesReverse = false;
+
+        if ((xDir != 0) && 
+                (-xDir == dimDirection(inf3->point.x - inf2->point.x)))
+        {
+            // Connector has an X component and the segment heads in the 
+            // opposite direction.
+            doesReverse |= true;
+        }
+
+        if ((yDir != 0) && 
+                (-yDir == dimDirection(inf3->point.y - inf2->point.y)))
+        {
+            // Connector has an Y component and the segment heads in the 
+            // opposite direction.
+            doesReverse |= true;
+        }
+
+        if (doesReverse)
+        {
+            result += reversePenalty;
         }
     }
 
+    if (!router->isInCrossingPenaltyReroutingStage())
+    {
+        // Return here if we are not in the post-processing stage 
+        return result;
+    }
+
+    const double crossing_penalty = router->routingParameter(crossingPenalty);
     const double shared_path_penalty = 
-            router->routingPenalty(fixedSharedPathPenalty);
-    if (shared_path_penalty > 0)
+            router->routingParameter(fixedSharedPathPenalty);
+    if ((shared_path_penalty > 0) || (crossing_penalty > 0))
     {
-        // Penalises shared paths, except if the connectors shared an endpoint.
         if (connRoute.empty())
         {
-            constructPolygonPath(connRoute, inf2, inf3, done, inf1Index);
+            constructPolygonPath(connRoute, inf2, inf3, inf1Node);
         }
         ConnRefList::const_iterator curr, finish = router->connRefs.end();
         for (curr = router->connRefs.begin(); curr != finish; ++curr)
@@ -267,104 +455,422 @@ static double cost(ConnRef *lineRef, const double dist, VertInf *inf2,
             {
                 continue;
             }
-            const Avoid::PolyLine& route2 = connRef->route();
+            const Avoid::PolyLine& route2 = connRef->displayRoute();
             
             bool isConn = true;
             Polygon dynamic_route2(route2);
             Polygon dynamic_conn_route(connRoute);
-            CrossingsInfoPair crossings = countRealCrossings(
-                    dynamic_route2, isConn, dynamic_conn_route, 
-                    connRoute.size() - 1, false, false, NULL, NULL,
-                    connRef, lineRef);
-
-            if ((crossings.second & CROSSING_SHARES_PATH) &&
-                    (crossings.second & CROSSING_SHARES_FIXED_SEGMENT) &&
-                    !(crossings.second & CROSSING_SHARES_PATH_AT_END))
+            const bool finalSegment = (inf3->point == lineRef->dst()->point);
+            ConnectorCrossings cross(dynamic_route2, isConn, 
+                    dynamic_conn_route, connRef, lineRef);
+            cross.checkForBranchingSegments = true;
+            cross.countForSegment(connRoute.size() - 1, finalSegment);
+
+            if ((cross.crossingFlags & CROSSING_SHARES_PATH) &&
+                    (cross.crossingFlags & CROSSING_SHARES_FIXED_SEGMENT) &&
+                    (router->routingOption(
+                            penaliseOrthogonalSharedPathsAtConnEnds) || 
+                     !(cross.crossingFlags & CROSSING_SHARES_PATH_AT_END))) 
             {
-                // Penalise unecessary shared paths in the middle of
+                // Penalise unnecessary shared paths in the middle of
                 // connectors.
                 result += shared_path_penalty;
             }
+            result += (cross.crossingCount * crossing_penalty);
         }
     }
 
-    const double crossing_penalty = router->routingPenalty(crossingPenalty);
-    if (lineRef->doesHateCrossings() && (crossing_penalty > 0))
+    return result;
+}
+
+// Directions for estimated orthgonal cost, as bitflags.
+static const unsigned int CostDirectionN = 1;
+static const unsigned int CostDirectionE = 2;
+static const unsigned int CostDirectionS = 4;
+static const unsigned int CostDirectionW = 8;
+
+#ifdef ESTIMATED_COST_DEBUG
+static void printDirections(FILE *fp, unsigned int directions)
+{
+    if (directions & CostDirectionN)
     {
-        if (connRoute.empty())
-        {
-            constructPolygonPath(connRoute, inf2, inf3, done, inf1Index);
-        }
-        ConnRefList::const_iterator curr, finish = router->connRefs.end();
-        for (curr = router->connRefs.begin(); curr != finish; ++curr)
-        {
-            ConnRef *connRef = *curr;
+        fprintf(fp, "N ");
+    }
+    if (directions & CostDirectionE)
+    {
+        fprintf(fp, "E ");
+    }
+    if (directions & CostDirectionS)
+    {
+        fprintf(fp, "S ");
+    }
+    if (directions & CostDirectionW)
+    {
+        fprintf(fp, "W ");
+    }
+}
+#endif
 
-            if (connRef->id() == lineRef->id())
-            {
-                continue;
-            }
-            const Avoid::PolyLine& route2 = connRef->route();
-            
-            bool isConn = true;
-            Polygon dynamic_route2(route2);
-            Polygon dynamic_conn_route(connRoute);
-            CrossingsInfoPair crossings = countRealCrossings(
-                    dynamic_route2, isConn, dynamic_conn_route, 
-                    connRoute.size() - 1, true);
-            result += (crossings.first * crossing_penalty);
-        }
+// Returns the number of directions for the argument.
+static unsigned int orthogonalDirectionsCount(const unsigned int directions)
+{
+    unsigned int count = 0;
+    if (directions & CostDirectionN)
+    {
+        ++count;
+    }
+    if (directions & CostDirectionE)
+    {
+        ++count;
+    }
+    if (directions & CostDirectionS)
+    {
+        ++count;
+    }
+    if (directions & CostDirectionW)
+    {
+        ++count;
+    }
+    return count;
+}
+
+// Returns the directions of point b from point a.
+static unsigned int orthogonalDirection(const Point &a, const Point &b)
+{
+    unsigned int result = 0;
+
+    if (b.y > a.y)
+    {
+        result |= CostDirectionS;
+    }
+    else if (b.y < a.y)
+    {
+        result |= CostDirectionN;
+    }
+
+    if (b.x > a.x)
+    {
+        result |= CostDirectionE;
+    }
+    else if (b.x < a.x)
+    {
+        result |= CostDirectionW;
     }
 
     return result;
 }
 
+// Returns the direction to the right of the given direction.
+static unsigned int dirRight(unsigned int direction)
+{
+    if (direction == CostDirectionN)
+    {
+        return CostDirectionE;
+    }
+    else if (direction == CostDirectionE)
+    {
+        return CostDirectionS;
+    }
+    else if (direction == CostDirectionS)
+    {
+        return CostDirectionW;
+    }
+    else if (direction == CostDirectionW)
+    {
+        return CostDirectionN;
+    }
+    
+    // Should not be possible to reach here.
+    COLA_ASSERT(false);
+    return direction;
+}
+
+// Returns the direction to the left of the given direction.
+static unsigned int dirLeft(unsigned int direction)
+{
+    if (direction == CostDirectionN)
+    {
+        return CostDirectionW;
+    }
+    else if (direction == CostDirectionE)
+    {
+        return CostDirectionN;
+    }
+    else if (direction == CostDirectionS)
+    {
+        return CostDirectionE;
+    }
+    else if (direction == CostDirectionW)
+    {
+        return CostDirectionS;
+    }
+    
+    // Should not be possible to reach here.
+    COLA_ASSERT(false);
+    return direction;
+}
+
+// Returns the reverse direction to the given direction.
+static unsigned int dirReverse(unsigned int direction)
+{
+    if (direction == CostDirectionN)
+    {
+        return CostDirectionS;
+    }
+    else if (direction == CostDirectionE)
+    {
+        return CostDirectionW;
+    }
+    else if (direction == CostDirectionS)
+    {
+        return CostDirectionN;
+    }
+    else if (direction == CostDirectionW)
+    {
+        return CostDirectionE;
+    }
+    
+    // Should not be possible to reach here.
+    COLA_ASSERT(false);
+    return direction;
+}
+
+// Given Point curr with a direction of currDir, returns the nimimum number 
+// of bends to reach Point dest with the entry direction of destDir
+// 
+// This is used for estimating the bend penalty cost to the target point
+// from the current point of the search. The geometry was described in the 
+// "Orthogonal Connector Routing" paper, although the version described 
+// there is incorrect.
+//
+int bends(const Point& curr, unsigned int currDir, const Point& dest,
+        unsigned int destDir)
+{
+        // Bend counts from 'o' to 'D' should be:
+        //
+        //                1            1            3
+        //                v            v            v
+        //            2 > o < 2    2 > o < 2    4 > o < 2
+        //                ^            ^            ^
+        //                3            3            3
+        //                                      
+        //   0 > o < 4                 D-->             4 > o < 4
+        //       ^                                          ^
+        //       1                                          3
+        //
+    COLA_ASSERT(currDir != 0);
+    unsigned int currToDestDir = orthogonalDirection(curr, dest);
+    unsigned int reverseDestDir = dirReverse(destDir);
+    bool currDirPerpendicularToDestDir =
+            (currDir == dirLeft(destDir)) || (currDir == dirRight(destDir));
+
+    if ((currDir == destDir) &&
+             (currToDestDir == currDir))
+    {
+        //                                      
+        //   0 > o                     D--> 
+        //
+        return 0;
+    }
+    else if (currDirPerpendicularToDestDir &&
+             (currToDestDir == (destDir | currDir)))
+    {
+        //
+        //                1
+        //                v
+        //                o
+        //                 
+        //                                      
+        //                             D-->
+        //
+        return 1;
+    }
+    else if (currDirPerpendicularToDestDir &&
+             (currToDestDir == currDir))
+    {
+        //
+        //                             1
+        //                             v
+        //                             o
+        //                 
+        //                                      
+        //                             D-->
+        //
+        return 1;
+    }
+    else if (currDirPerpendicularToDestDir &&
+             (currToDestDir == destDir))
+    {
+        //
+        //       o                     D-->
+        //       ^
+        //       1
+        //
+        return 1;
+    }
+    else if ((currDir == destDir) && 
+             (currToDestDir != currDir) &&
+             !(currToDestDir & reverseDestDir))
+    {
+        //
+        //            2 > o        2 > o
+        //
+        //                                      
+        //                             D-->
+        //
+        return 2;
+    }
+    else if (currDir == reverseDestDir && 
+             (currToDestDir != destDir) &&
+             (currToDestDir != currDir))
+    {
+        //
+        //                o < 2        o < 2       o < 2
+        //
+        //                                      
+        //                             D-->
+        //
+        return 2;
+    }
+    else if (currDirPerpendicularToDestDir &&
+             (currToDestDir != (destDir | currDir)) && 
+             (currToDestDir != currDir))
+    {
+        //
+        //                                          3
+        //                                          v
+        //                o            o            o
+        //                ^            ^            ^
+        //                3            3            3
+        //                                      
+        //                             D-->                 o
+        //                                                  ^
+        //                                                  3
+        //
+        return 3;
+    }
+    else if ((currDir == reverseDestDir) && 
+             ((currToDestDir == destDir) || (currToDestDir == currDir)))
+    {
+        //
+        //                                      
+        //                                      
+        //       o < 4                 D-->                 o < 4
+        //
+        return 4;
+    }
+    else if ((currDir == destDir) && 
+             (currToDestDir & reverseDestDir))
+    {
+        //
+        //                                      4 > o
+        //                                      
+        //                                      
+        //                             D-->             4 > o
+        //
+        return 4;
+    }
+
+    // Should not be possible to reach here.
+    COLA_ASSERT(false);
+    return 0;
+}
+
 
-static double estimatedCost(ConnRef *lineRef, const Point *last, 
-        const Point& a, const Point& b)
+static double estimatedCostSpecific(ConnRef *lineRef, const Point *last,
+        const Point& curr, const VertInf *costTar,
+        const unsigned int costTarDirs)
 {
+    Point costTarPoint = costTar->point;
+
     if (lineRef->routingType() == ConnType_PolyLine)
     {
-        return euclideanDist(a, b);
+        return euclideanDist(curr, costTarPoint);
     }
     else // Orthogonal
     {
-        // XXX: This currently just takes into account the compulsory
-        //      bend but will have to be updated when port direction 
-        //      information is available.
-        int num_penalties = 0;
-        double xmove = b.x - a.x;
-        double ymove = b.y - a.y;
-        if (!last)
+        // Really doesn't make sense to route orthogonal paths without 
+        // a segment penalty.
+        COLA_ASSERT(lineRef->router()->routingParameter(segmentPenalty) > 0);
+
+        double dist = manhattanDist(curr, costTarPoint);
+
+        int bendCount = 0;
+        double xmove = costTarPoint.x - curr.x;
+        double ymove = costTarPoint.y - curr.y;
+        if (last == NULL)
         {
-            // Just two points.
+            // This is just the initial point.  Penalise it simply if it is 
+            // not inline with the target in either the x- or y-dimension.
             if ((xmove != 0) && (ymove != 0))
             {
-                num_penalties += 1;
+                bendCount += 1;
             }
         }
-        else
+        else if (dist > 0)
         {
-            // We have three points, so we know the direction of the 
-            // previous segment.
-            double rad = M_PI - angleBetween(*last, a, b);
-            if (rad > (M_PI / 2))            
-            {
-                // Target point is back in the direction of the first point,
-                // so at least two bends are required.
-                num_penalties += 2;
-            }
-            else if (rad > 0)
+            // We have two points and a non-zero distance, so we know 
+            // the segment direction.
+
+            unsigned int currDir = orthogonalDirection(*last, curr);
+            if ((currDir > 0) && (orthogonalDirectionsCount(currDir) == 1))
             {
-                // To the side, so at least one bend.
-                num_penalties += 1;
+                // Suitably high value, then we find the minimum.
+                bendCount = 10;
+
+                // Find the minimum bent penalty given all the possible 
+                // directions at the target point.
+                if (costTarDirs & CostDirectionN)
+                {
+                    bendCount = std::min(bendCount,
+                            bends(curr, currDir, costTarPoint, CostDirectionN));
+                }
+                if (costTarDirs & CostDirectionE)
+                {
+                    bendCount = std::min(bendCount,
+                            bends(curr, currDir, costTarPoint, CostDirectionE));
+                }
+                if (costTarDirs & CostDirectionS)
+                {
+                    bendCount = std::min(bendCount,
+                            bends(curr, currDir, costTarPoint, CostDirectionS));
+                }
+                if (costTarDirs & CostDirectionW)
+                {
+                    bendCount = std::min(bendCount,
+                            bends(curr, currDir, costTarPoint, CostDirectionW));
+                }
             }
         }
-        double penalty = num_penalties * 
-                lineRef->router()->routingPenalty(segmentPenalty);
+        double penalty = bendCount *
+                lineRef->router()->routingParameter(segmentPenalty);
+
+        return dist + penalty;
+    }
+}
+
 
-        return manhattanDist(a, b) + penalty;
+
+double AStarPathPrivate::estimatedCost(ConnRef *lineRef, const Point *last,
+        const Point& curr) const
+{
+    double estimate = DBL_MAX;
+    COLA_ASSERT(m_cost_targets.size() > 0);
+
+    // Find the minimum cost from the estimates to each of the possible
+    // target points from this current point.
+    for (size_t i = 0; i < m_cost_targets.size(); ++i)
+    {
+        double iEstimate = estimatedCostSpecific(lineRef, last,
+                curr, m_cost_targets[i], m_cost_targets_directions[i]);
+        
+        // Add on the distance to the real target, otherwise this difference
+        // might may make the comparisons unfair if they vary between targets.
+        iEstimate += m_cost_targets_displacements[i];
+        
+        estimate = std::min(estimate, iEstimate);
     }
+    return estimate;
 }
 
 
@@ -377,41 +883,200 @@ class CmpVisEdgeRotation
         }
         bool operator() (const EdgeInf* u, const EdgeInf* v) const 
         {
-            return u->rotationLessThan(_lastPt, v);
+            // Dummy ShapeConnectionPin edges are not orthogonal and 
+            // therefore can't be compared in the same way.
+            if (u->isOrthogonal() && v->isOrthogonal())
+            {
+                return u->rotationLessThan(_lastPt, v);
+            }
+            return u < v;
         }
     private:
         const VertInf *_lastPt;
 };
 
 
+static inline bool pointAlignedWithOneOf(const Point& point, 
+        const std::vector<Point>& points, const size_t dim)
+{
+    for (size_t i = 0; i < points.size(); ++i)
+    {
+        if (point[dim] == points[i][dim])
+        {
+            return true;
+        }
+    }
+    return false;
+}
+
+AStarPath::AStarPath(void)
+    : m_private(new AStarPathPrivate())
+{
+}
+
+AStarPath::~AStarPath(void)
+{
+    delete m_private;
+}
+
+void AStarPath::search(ConnRef *lineRef, VertInf *src, VertInf *tar, VertInf *start)
+{
+    m_private->search(lineRef, src, tar, start);
+}
+
+void AStarPathPrivate::determineEndPointLocation(double dist, VertInf *start, 
+        VertInf *target, VertInf *other, int level)
+{
+    COLA_UNUSED(dist);
+    COLA_UNUSED(start);
+    COLA_UNUSED(level);
+
+    Point otherPoint = other->point;
+    unsigned int thisDirs = orthogonalDirection(otherPoint, target->point);
+    COLA_ASSERT(orthogonalDirectionsCount(thisDirs) > 0);
+    double displacement = manhattanDist(otherPoint, target->point);
+
+    m_cost_targets.push_back(other);
+    m_cost_targets_directions.push_back(thisDirs);
+    m_cost_targets_displacements.push_back(displacement);
+
+#ifdef ESTIMATED_COST_DEBUG
+    fprintf(stderr," - %g %g ", otherPoint.x, otherPoint.y);
+    if (manhattanDist(start->point, otherPoint) > dist)
+    {
+        fprintf(stderr,"far ");
+    }
+    fprintf(stderr, "%s", (level == 1) ? "--" : "- ");
+    printDirections(stderr, thisDirs);
+    fprintf(stderr,"\n");
+#endif
+}
+
 // Returns the best path from src to tar using the cost function.
 //
 // The path is worked out using the aStar algorithm, and is encoded via
-// prevIndex values for each ANode which point back to the previous ANode's
-// position in the DONE vector.  At completion, this order is written into
-// the pathNext links in each of the VerInfs along the path.
+// prevNode values for each ANode which point back to the previous ANode.
+// At completion, this order is written into the pathNext links in each 
+// of the VerInfs along the path.
 //
-// The aStar STL code is based on public domain code available on the
-// internet.
+// The aStar STL code is originally based on public domain code available 
+// on the internet.
 //
-static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar, 
-        VertInf *start)
+void AStarPathPrivate::search(ConnRef *lineRef, VertInf *src, VertInf *tar, VertInf *start)
 {
+    ANodeCmp pendingCmp;
+
     bool isOrthogonal = (lineRef->routingType() == ConnType_Orthogonal);
 
+    if (start == NULL)
+    {
+        start = src;
+    }
+
+#ifdef DEBUGHANDLER
+    if (lineRef->router()->debugHandler())
+    {
+        lineRef->router()->debugHandler()->beginningSearchWithEndpoints(start, tar);
+    }
+#endif
+
+    // Find a target point to use for cost estimate for orthogonal routing.
+    //
+    // If the connectivity is only on the far side we need to estimate to the
+    // point on the far side.  Otherwise for orthogonal routing we can explore
+    // all the space in between before we pay the extra cost to explore this
+    // area.  This is especially true given many orthogonal routes have 
+    // equivalent costs.
+#ifdef ESTIMATED_COST_DEBUG
+    fprintf(stderr,"== aStar  %g %g ==\n", tar->point.x, tar->point.y);
+#endif
+    if (isOrthogonal && tar->id.isConnPt() && !tar->id.isConnCheckpoint())
+    {
+        // The target is a connector endpoint and the connector is orthogonal.
+        double dist = manhattanDist(start->point, tar->point);
+        for (EdgeInfList::const_iterator it = tar->orthogVisList.begin(); 
+                it != tar->orthogVisList.end(); ++it)
+        {
+            // For each edge from the target endpoint, find the other vertex.
+            EdgeInf *edge = *it;
+            VertInf *other = edge->otherVert(tar);
+            if (other->id.isConnectionPin())
+            {
+                // If this is a connection pin we need to do this process
+                // another time since the current edge will be a dummy 
+                // zero-length edge.
+                VertInf *replacementTar = other;
+                for (EdgeInfList::const_iterator it = 
+                        replacementTar->orthogVisList.begin(); 
+                        it != replacementTar->orthogVisList.end(); ++it)
+                {
+                    EdgeInf *edge = *it;
+                    VertInf *other = edge->otherVert(replacementTar);
+                    if ((other == tar) || 
+                            (other->point == tar->point))
+                    {
+                        // Ignore edge we came from, or zero-length edges.
+                        continue;
+                    }
+
+                    // Determine possible target endpoint directions and 
+                    // position.
+                    determineEndPointLocation(dist, start, replacementTar,
+                            other, 2);
+                }
+                continue;
+            }
+                    
+            // Determine possible target endpoint directions and position.
+            determineEndPointLocation(dist, start, tar, other, 1);
+        }
+    }
+
+
+    if (m_cost_targets.empty())
+    {
+        m_cost_targets.push_back(tar);
+        // For polyline routing, assume target has visibility is all 
+        // directions for the purpose of cost estimations.
+        m_cost_targets_directions.push_back(CostDirectionN |
+                CostDirectionE | CostDirectionS | CostDirectionW);
+        m_cost_targets_displacements.push_back(0.0);
+    }
+
+#ifdef ESTIMATED_COST_DEBUG
+    fprintf(stderr, "------------\n");
+    for (size_t i = 0; i < m_cost_targets.size(); ++i)
+    {
+        fprintf(stderr,"== %g %g - ", m_cost_targets[i]->point.x,
+                m_cost_targets[i]->point.y);
+        printDirections(stderr, m_cost_targets_directions[i]);
+        fprintf(stderr,"\n");
+    }
+#endif
+
+
     double (*dist)(const Point& a, const Point& b) = 
         (isOrthogonal) ? manhattanDist : euclideanDist;
 
-    std::vector<ANode> PENDING;     // STL Vectors chosen because of rapid
-    std::vector<ANode> DONE;        // insertions/deletions at back,
-    ANode Node, BestNode;           // Temporary Node and BestNode
-    bool bNodeFound = false;        // Flag if node is found in container
-    int timestamp = 1;
-
-    if (start == NULL)
+    // We need to know the possible endpoints for doing an orthogonal 
+    // routing optimisation where we only turn when we are heading beside
+    // a shape or are in line with a possible endpoint.
+    std::vector<Point> endPoints;
+    if (isOrthogonal)
     {
-        start = src;
+        endPoints = lineRef->possibleDstPinPoints();
     }
+    endPoints.push_back(tar->point);
+    
+    // Heap of PENDING nodes.
+    std::vector<ANode *> PENDING;
+    PENDING.reserve(1000);
+
+    size_t exploredCount = 0;
+    ANode node, ati;
+    ANode *bestNode = NULL;         // Temporary bestNode
+    bool bNodeFound = false;        // Flag if node is found in container
+    int timestamp = 1;
 
     Router *router = lineRef->router();
     if (router->RubberBandRouting && (start != src))
@@ -424,50 +1089,53 @@ static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar,
         while (last != start)
         {
             const Point& pnt = currRoute.at(rIndx);
-            bool isShape = (rIndx > 0);
-            VertID vID(pnt.id, isShape, pnt.vn);
+            VertIDProps props = (rIndx > 0) ? 0 : VertID::PROP_ConnPoint;
+            VertID vID(pnt.id, pnt.vn, props);
 
 #ifdef PATHDEBUG
-            db_printf("/// %d %d %d\n", pnt.id, (int) isShape, pnt.vn);
+            db_printf("/// %d %d\n", pnt.id, pnt.vn);
 #endif
             VertInf *curr = router->vertices.getVertexByID(vID);
             COLA_ASSERT(curr != NULL);
 
-            Node = ANode(curr, timestamp++);
+            node = ANode(curr, timestamp++);
             if (!last)
             {
-                Node.g = 0;
-                Node.h = estimatedCost(lineRef, NULL, Node.inf->point, 
-                        tar->point);
-                Node.f = Node.g + Node.h;
+                node.inf = src;
+                node.g = 0;
+                node.h = estimatedCost(lineRef, NULL, node.inf->point);
+
+                node.f = node.g + node.h;
             }
             else
             {
-                double edgeDist = dist(BestNode.inf->point, curr->point);
+                double edgeDist = dist(bestNode->inf->point, curr->point);
 
-                Node.g = BestNode.g + cost(lineRef, edgeDist, BestNode.inf, 
-                        Node.inf, DONE, BestNode.prevIndex);
+                node.g = bestNode->g + cost(lineRef, edgeDist, bestNode->inf, 
+                        node.inf, bestNode->prevNode);
 
                 // Calculate the Heuristic.
-                Node.h = estimatedCost(lineRef, &(BestNode.inf->point),
-                        Node.inf->point, tar->point);
+                node.h = estimatedCost(lineRef, &(bestNode->inf->point),
+                        node.inf->point);
 
                 // The A* formula
-                Node.f = Node.g + Node.h;
+                node.f = node.g + node.h;
                 
-                // Point parent to last BestNode (pushed onto DONE)
-                Node.prevIndex = DONE.size() - 1;
+                // Point parent to last bestNode
+                node.prevNode = bestNode;
             }
 
             if (curr != start)
             {
-                BestNode = Node;
-
-                DONE.push_back(BestNode);
+                bool addToPending = false;
+                bestNode = newANode(node, addToPending);
+                bestNode->inf->aStarDoneNodes.push_back(bestNode);
+                ++exploredCount;
             }
             else
             {
-                PENDING.push_back(Node);
+                ANode * newNode = newANode(node);
+                PENDING.push_back(newNode);
             }
 
             rIndx++;
@@ -476,48 +1144,97 @@ static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar,
     }
     else
     {
+        if (start->pathNext)
+        {
+            // If we are doing checkpoint routing and have already done one
+            // path, then we have an existing segment to consider for the 
+            // cost of the  choice from the start node, so we add a dummy 
+            // nodes as if they were already in the Done set.  This causes 
+            // us to first search in a collinear direction from the previous 
+            // segment.
+            bool addToPending = false;
+            bestNode = newANode(ANode(start->pathNext, timestamp++), 
+                    addToPending);
+            bestNode->inf->aStarDoneNodes.push_back(bestNode);
+            ++exploredCount;
+        }
+
         // Create the start node
-        Node = ANode(src, timestamp++);
-        Node.g = 0;
-        Node.h = estimatedCost(lineRef, NULL, Node.inf->point, tar->point);
-        Node.f = Node.g + Node.h;
+        node = ANode(src, timestamp++);
+        node.g = 0;
+        node.h = estimatedCost(lineRef, NULL, node.inf->point);
+        node.f = node.g + node.h;
         // Set a null parent, so cost function knows this is the first segment.
+        node.prevNode = bestNode;
 
         // Populate the PENDING container with the first location
-        PENDING.push_back(Node);
+        ANode *newNode = newANode(node);
+        PENDING.push_back(newNode);
     }
 
     tar->pathNext = NULL;
 
     // Create a heap from PENDING for sorting
     using std::make_heap; using std::push_heap; using std::pop_heap;
-    make_heap( PENDING.begin(), PENDING.end() );
+    make_heap( PENDING.begin(), PENDING.end(), pendingCmp);
 
+    // Continue until the queue is empty.
     while (!PENDING.empty())
     {
+        TIMER_VAR_ADD(router, 0, 1);
         // Set the Node with lowest f value to BESTNODE.
         // Since the ANode operator< is reversed, the head of the
         // heap is the node with the lowest f value.
-        BestNode = PENDING.front();
+        bestNode = PENDING.front();
+        VertInf *bestNodeInf = bestNode->inf;
+
+#ifdef DEBUGHANDLER
+        if (router->debugHandler())
+        {
+            PolyLine currentSearchPath;
+
+            ANode *curr = bestNode;
+            while (curr)
+            {
+                currentSearchPath.ps.push_back(curr->inf->point);
+                curr = curr->prevNode;
+            }
+            router->debugHandler()->updateCurrentSearchPath(currentSearchPath);
+        }
+#endif
+
+        // Remove this node from the aStarPendingList
+        std::list<ANode *>::iterator finishIt = 
+                bestNodeInf->aStarPendingNodes.end();
+        for (std::list<ANode *>::iterator currInd = 
+                bestNodeInf->aStarPendingNodes.begin(); currInd != finishIt; 
+                ++currInd)
+        {
+            if (*currInd == bestNode)
+            {
+                bestNodeInf->aStarPendingNodes.erase(currInd);
+                break;
+            }
+        }
 
         // Pop off the heap.  Actually this moves the
         // far left value to the far right.  The node
         // is not actually removed since the pop is to
         // the heap and not the container.
-        pop_heap(PENDING.begin(), PENDING.end());
+        pop_heap(PENDING.begin(), PENDING.end(), pendingCmp);
         // Remove node from right (the value we pop_heap'd)
         PENDING.pop_back();
 
-        // Push the BestNode onto DONE
-        DONE.push_back(BestNode);
+        // Add the bestNode into the Done set.
+        bestNodeInf->aStarDoneNodes.push_back(bestNode);
+        ++exploredCount;
 
-        VertInf *prevInf = (BestNode.prevIndex >= 0) ?
-                DONE[BestNode.prevIndex].inf : NULL;
-#if 0
+        VertInf *prevInf = (bestNode->prevNode) ? bestNode->prevNode->inf : NULL;
+#ifdef ASTAR_DEBUG
         db_printf("Considering... ");
-        db_printf(" %g %g  ", BestNode.inf->point.x, BestNode.inf->point.y);
-        BestNode.inf->id.db_print();
-        db_printf(" - g: %3.1f h: %3.1f back: ", BestNode.g, BestNode.h);
+        db_printf(" %g %g  ", bestNodeInf->point.x, bestNodeInf->point.y);
+        bestNodeInf->id.db_print();
+        db_printf(" - g: %3.1f h: %3.1f back: ", bestNode->g, bestNode->h);
         if (prevInf)
         {
             db_printf(" %g %g", prevInf->point.x, prevInf->point.y);
@@ -526,81 +1243,34 @@ static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar,
         db_printf("\n");
 #endif
 
-#if defined(ASTAR_DEBUG)
-        if (router->avoid_screen)
-        {
-            int canx = 151;
-            int cany = 55;
-            int radius = 5;
-            ANode curr;
-            for (curr = BestNode; curr.prevIndex >= 0; 
-                    curr = DONE[curr.prevIndex])
-            {
-                filledCircleRGBA(router->avoid_screen, 
-                        (int) curr.inf->point.x + canx,
-                        (int) curr.inf->point.y + cany, 
-                        radius, 0, 0, 255, 128);
-            }
-            filledCircleRGBA(router->avoid_screen, 
-                    (int) BestNode.inf->point.x + canx,
-                    (int) BestNode.inf->point.y + cany, 
-                    radius, 255, 0, 0, 255);
-
-            SDL_Flip(router->avoid_screen);
-            //SDL_Delay(500);
-
-            filledCircleRGBA(router->avoid_screen, 
-                    (int) BestNode.inf->point.x + canx,
-                    (int) BestNode.inf->point.y + cany, 
-                    radius, 255, 255, 255, 255);
-            filledCircleRGBA(router->avoid_screen, 
-                    (int) BestNode.inf->point.x + canx,
-                    (int) BestNode.inf->point.y + cany, 
-                    radius, 0, 255, 0, 128);
-            for (curr = BestNode; curr.prevIndex >= 0; 
-                    curr = DONE[curr.prevIndex])
-            {
-                filledCircleRGBA(router->avoid_screen, 
-                        (int) curr.inf->point.x + canx,
-                        (int) curr.inf->point.y + cany, 
-                        radius, 255, 255, 255, 255);
-                filledCircleRGBA(router->avoid_screen, 
-                        (int) curr.inf->point.x + canx,
-                        (int) curr.inf->point.y + cany, 
-                        radius, 0, 255, 0, 128);
-            }
-        }
-#endif
-
-        // If at destination, break and create path below
-        if (BestNode.inf == tar)
+        if (bestNodeInf == tar)
         {
-#ifdef PATHDEBUG
-            db_printf("Cost: %g\n", BestNode.f);
+            TIMER_VAR_ADD(router, 1, PENDING.size());
+            // This node is our goal.
+#ifdef ASTAR_DEBUG
+            db_printf("LINE %10d  Steps: %4d  Cost: %g\n", lineRef->id(), 
+                    (int) exploredCount, bestNode->f);
 #endif
-            //bPathFound = true; // arrived at destination...
-            
+     
             // Correct all the pathNext pointers.
-            ANode curr;
-            int currIndex = DONE.size() - 1;
-            for (curr = BestNode; curr.prevIndex > 0; 
-                    curr = DONE[curr.prevIndex])
+            for (ANode *curr = bestNode; curr->prevNode; curr = curr->prevNode)
             {
-                COLA_ASSERT(curr.prevIndex < currIndex);   
-                curr.inf->pathNext = DONE[curr.prevIndex].inf;
-                currIndex = curr.prevIndex;
+#ifdef ASTAR_DEBUG
+                db_printf("[%.12f, %.12f]\n", curr->inf->point.x, curr->inf->point.y);
+#endif
+                curr->inf->pathNext = curr->prevNode->inf;
             }
-            // Check that we've gone through the complete path.
-            COLA_ASSERT(curr.prevIndex == 0);
-            // Fill in the final pathNext pointer.
-            curr.inf->pathNext = DONE[curr.prevIndex].inf;
+#ifdef ASTAR_DEBUG
+            db_printf("\n");
+#endif
 
+            // Exit from the search
             break;
         }
 
-        // Check adjacent points in graph
+        // Check adjacent points in graph and add them to the queue.
         EdgeInfList& visList = (!isOrthogonal) ?
-                BestNode.inf->visList : BestNode.inf->orthogVisList;
+                bestNodeInf->visList : bestNodeInf->orthogVisList;
         if (isOrthogonal)
         {
             // We would like to explore in a structured way, 
@@ -612,26 +1282,108 @@ static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar,
         for (EdgeInfList::const_iterator edge = visList.begin(); 
                 edge != finish; ++edge)
         {
-            Node = ANode((*edge)->otherVert(BestNode.inf), timestamp++);
-
-            // Set the index to the previous ANode that we reached
-            // this ANode through (the last BestNode pushed onto DONE).
-            Node.prevIndex = DONE.size() - 1;
-
-            // Only check shape verticies, or the tar endpoint.
-            if (!(Node.inf->id.isShape) && (Node.inf != tar))
+            if ((*edge)->isDisabled())
             {
+                // Skip disabled edges.
                 continue;
             }
 
-            VertInf *prevInf = (BestNode.prevIndex >= 0) ?
-                    DONE[BestNode.prevIndex].inf : NULL;
+            node = ANode((*edge)->otherVert(bestNodeInf), timestamp++);
+            
+            // Set the index to the previous ANode that we reached
+            // this ANode via.
+            node.prevNode = bestNode;
+
+            VertInf *prevInf = (bestNode->prevNode) ?
+                    bestNode->prevNode->inf : NULL;
 
             // Don't bother looking at the segment we just arrived along.
-            if (prevInf && (prevInf == Node.inf))
+            if (prevInf && (prevInf == node.inf))
             {
                 continue;
             }
+            if (node.inf->id.isConnectionPin() && 
+                    !node.inf->id.isConnCheckpoint())
+            {
+                if ( !( (bestNodeInf == lineRef->src()) &&
+                        lineRef->src()->id.isDummyPinHelper()
+                      ) &&
+                     !( node.inf->hasNeighbour(lineRef->dst(), isOrthogonal) &&
+                        lineRef->dst()->id.isDummyPinHelper())
+                      )
+                {
+                    // Don't check connection pins if they don't have the 
+                    // target vertex as a direct neighbour, or are directly
+                    // leaving the source vertex.
+                    continue;
+                }
+            }
+            else if (node.inf->id.isConnPt())
+            {
+                if ((node.inf != tar))
+                {
+                    // Don't check connector endpoints vertices unless they
+                    // are the target endpoint.
+                    continue;
+                }
+            }
+
+            if (isOrthogonal && !(*edge)->isDummyConnection())
+            {
+                // Orthogonal routing optimisation.
+                // Skip the edges that don't lead to shape edges, or the 
+                // connection point we are looking for.  Though allow them
+                // if we haven't yet turned from the source point, since it
+                // may be a free-floating endpoint with directional visibility.
+                // Also, don't check if the previous point was a dummy for a
+                // connection pin and this happens to be placed diagonally 
+                // from here, i.e., when both of notInline{X,Y} are true.
+                Point& bestPt = bestNodeInf->point;
+                Point& nextPt = node.inf->point;
+
+                bool notInlineX = prevInf && (prevInf->point.x != bestPt.x);
+                bool notInlineY = prevInf && (prevInf->point.y != bestPt.y);
+                if ((bestPt.x == nextPt.x) && notInlineX && !notInlineY &&
+                        (bestPt[YDIM] != src->point[YDIM]))
+                {
+                    if (nextPt.y < bestPt.y)
+                    {
+                        if (!(bestNodeInf->orthogVisPropFlags & YL_EDGE) &&
+                                !pointAlignedWithOneOf(bestPt, endPoints, XDIM))
+                        {
+                            continue;
+                        }
+                    }
+                    else if (nextPt.y > bestPt.y)
+                    {
+                        if (!(bestNodeInf->orthogVisPropFlags & YH_EDGE) &&
+                                !pointAlignedWithOneOf(bestPt, endPoints, XDIM))
+                        {
+                            continue;
+                        }
+                    }
+                }
+                if ((bestPt.y == nextPt.y) && notInlineY && !notInlineX &&
+                        (bestPt[XDIM] != src->point[XDIM]))
+                {
+                    if (nextPt.x < bestPt.x)
+                    {
+                        if (!(bestNodeInf->orthogVisPropFlags & XL_EDGE) &&
+                                !pointAlignedWithOneOf(bestPt, endPoints, YDIM))
+                        {
+                            continue;
+                        }
+                    }
+                    else if (nextPt.x > bestPt.x)
+                    {
+                        if (!(bestNodeInf->orthogVisPropFlags & XH_EDGE) &&
+                                !pointAlignedWithOneOf(bestPt, endPoints, YDIM))
+                        {
+                            continue;
+                        }
+                    }
+                }
+            }
 
             double edgeDist = (*edge)->getDist();
 
@@ -640,9 +1392,9 @@ static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar,
                 continue;
             }
 
-            if (!router->_orthogonalRouting &&
+            if (!isOrthogonal &&
                   (!router->RubberBandRouting || (start == src)) && 
-                  (validateBendPoint(prevInf, BestNode.inf, Node.inf) == false))
+                  (validateBendPoint(prevInf, bestNodeInf, node.inf) == false))
             {
                 // The bendpoint is not valid, i.e., is a zigzag corner, so...
                 continue;
@@ -651,142 +1403,149 @@ static void aStarPath(ConnRef *lineRef, VertInf *src, VertInf *tar,
                 // can go the *really* long way round.
             }
 
-            Node.g = BestNode.g + cost(lineRef, edgeDist, BestNode.inf, 
-                    Node.inf, DONE, BestNode.prevIndex);
+            // Figure out if we are at one of the cost targets.
+            bool atCostTarget = false;
+            for (size_t i = 0; i < m_cost_targets.size(); ++i)
+            {
+                if (bestNode->inf == m_cost_targets[i])
+                        
+                {
+                    atCostTarget = true;
+                    break;
+                }
+            }
 
-            // Calculate the Heuristic.
-            Node.h = estimatedCost(lineRef, &(BestNode.inf->point),
-                    Node.inf->point, tar->point);
+            if (atCostTarget &&
+                    (node.inf->id.isConnectionPin() || (node.inf == tar)))
+            {
+                // This is a point on the side of an obstacle that connects
+                // to the target or a connection pin.  It should have no 
+                // further cost and the heuristic should be zero.
+                node.g = bestNode->g;
+                node.h = 0;
+            }
+            else 
+            {
+                if (node.inf == tar)
+                {
+                    // We've reached the target.  The heuristic should be zero.
+                    node.h = 0;
+                }
+                else
+                {
+                    // Otherwise, calculate the heuristic value.
+                    node.h = estimatedCost(lineRef, &(bestNodeInf->point),
+                            node.inf->point);
+                }
+                
+                if (node.inf->id.isDummyPinHelper())
+                {
+                    // This is connecting to a connection pin helper vertex.
+                    // There should be no additional cost for this step.
+                    node.g = bestNode->g;
+                }
+                else
+                {
+                    // Otherwise, calculate the cost of this step.
+                    node.g = bestNode->g + cost(lineRef, edgeDist, bestNodeInf, 
+                            node.inf, bestNode->prevNode);
+                }
+            }
 
             // The A* formula
-            Node.f = Node.g + Node.h;
+            node.f = node.g + node.h;
 
-#if 0
-            db_printf("-- Adding: %g %g  ", Node.inf->point.x, 
-                    Node.inf->point.y);
-            Node.inf->id.db_print();
-            db_printf(" - g: %3.1f h: %3.1f \n", Node.g, Node.h);
+#ifdef ASTAR_DEBUG
+            db_printf("-- Adding: %g %g  ", node.inf->point.x, 
+                    node.inf->point.y);
+            node.inf->id.db_print();
+            db_printf(" - g: %3.1f h: %3.1f \n", node.g, node.h);
 #endif
 
             bNodeFound = false;
 
+    
             // Check to see if already on PENDING
-            for (unsigned int i = 0; i < PENDING.size(); i++)
+            std::list<ANode *>::const_iterator finish = node.inf->aStarPendingNodes.end();
+            for (std::list<ANode *>::const_iterator currInd = 
+                    node.inf->aStarPendingNodes.begin(); currInd != finish; ++currInd)
             {
-                ANode& ati = PENDING.at(i);
-                if ((Node.inf == ati.inf) &&
-                        (DONE[Node.prevIndex].inf == DONE[ati.prevIndex].inf))
+                ati = **currInd;
+                // The (node.prevNode == ati.prevNode) is redundant, but may
+                // save checking the mosre costly prevNode->inf test if the
+                // Nodes are the same.
+                if ((node.inf == ati.inf) && 
+                        ((node.prevNode == ati.prevNode) ||
+                         (node.prevNode->inf == ati.prevNode->inf)))
                 {
                     // If already on PENDING
-                    if (Node.g < ati.g)
+                    if (node.g < ati.g)
                     {
-                        PENDING[i] = Node;
-
-                        make_heap( PENDING.begin(), PENDING.end() );
+                        // Replace the existing node in PENDING
+                        **currInd = node;
+                        make_heap( PENDING.begin(), PENDING.end(), pendingCmp);
                     }
                     bNodeFound = true;
                     break;
                 }
             }
-            if (!bNodeFound ) // If Node NOT found on PENDING
+            if ( !bNodeFound ) // If Node NOT found on PENDING
             {
-                // Check to see if already on DONE
-                for (unsigned int i = 0; i < DONE.size(); i++)
+                // Check to see if it is already in the Done set for this
+                // vertex.
+                for (std::list<ANode *>::const_iterator currInd = 
+                        node.inf->aStarDoneNodes.begin();
+                        currInd != node.inf->aStarDoneNodes.end(); ++currInd)
                 {
-                    ANode& ati = DONE.at(i);
-                    if ((Node.inf == ati.inf) && 
-                            (DONE[Node.prevIndex].inf == DONE[ati.prevIndex].inf))
+                    ati = **currInd;
+                    // The (node.prevNode == ati.prevNode) is redundant, but may
+                    // save checking the mosre costly prevNode->inf test if the
+                    // Nodes are the same.
+                    if ((node.inf == ati.inf) && ati.prevNode &&
+                            ((node.prevNode == ati.prevNode) ||
+                             (node.prevNode->inf == ati.prevNode->inf)))
                     {
-                        // If on DONE, Which has lower gone?
-                        if (Node.g < ati.g)
-                        {
-                            DONE[i] = Node;
-                        }
+                        //COLA_ASSERT(node.g >= (ati.g - 10e-10));
+                        // This node is already in the Done set and the 
+                        // current node also has a higher g-value, so we 
+                        // don't need to consider this node.
                         bNodeFound = true;
                         break;
                     }
                 }
             }
 
-            if (!bNodeFound ) // If Node NOT found on PENDING or DONE
+            if (!bNodeFound ) // If Node NOT in either Pending or Done.
             {
                 // Push NewNode onto PENDING
-                PENDING.push_back(Node);
+                ANode *newNode = newANode(node);
+                PENDING.push_back(newNode);
                 // Push NewNode onto heap
-                push_heap( PENDING.begin(), PENDING.end() );
+                push_heap( PENDING.begin(), PENDING.end(), pendingCmp);
 
 #if 0
                 using std::cout; using std::endl;
-                // Display PENDING and DONE containers (For Debugging)
+                // Display PENDING container (For Debugging)
                 cout << "PENDING:   ";
                 for (unsigned int i = 0; i < PENDING.size(); i++)
                 {
-                    cout << PENDING.at(i).g << "," << PENDING.at(i).h << ",";
-                    cout << PENDING.at(i).inf << "," << PENDING.at(i).pp << "  ";
-                }
-                cout << endl;
-                cout << "DONE:   ";
-                for (unsigned int i = 0; i < DONE.size(); i++)
-                {
-                    cout << DONE.at(i).g << "," << DONE.at(i).h << ",";
-                    cout << DONE.at(i).inf << "," << DONE.at(i).pp << "  ";
+                    cout << PENDING[i]->g << "," << PENDING[i]->h << ",";
+                    cout << PENDING[i]->inf << "," << PENDING[i]->pp << "  ";
                 }
                 cout << endl << endl;
 #endif
             }
         }
     }
-}
-
 
-// Returns the best path for the connector referred to by lineRef.
-//
-// The path encoded in the pathNext links in each of the VertInfs
-// backwards along the path, from the tar back to the source.
-//
-void makePath(ConnRef *lineRef, bool *flag)
-{
-    bool isOrthogonal = (lineRef->routingType() == ConnType_Orthogonal);
-    Router *router = lineRef->router();
-    VertInf *src = lineRef->src();
-    VertInf *tar = lineRef->dst();
-    VertInf *start = lineRef->start();
-
-    // TODO: Could be more efficient here.
-    if (isOrthogonal)
+    // Cleanup lists used to store Done and Pending sets for each vertex.
+    VertInf *endVert = router->vertices.end();
+    for (VertInf *k = router->vertices.connsBegin(); k != endVert;
+            k = k->lstNext)
     {
-        aStarPath(lineRef, src, tar, start);
+        k->aStarDoneNodes.clear();
+        k->aStarPendingNodes.clear();
     }
-    else // if (!isOrthogonal)
-    {
-        EdgeInf *directEdge = EdgeInf::existingEdge(src, tar);
-        // If the connector hates crossings or there are clusters present,
-        // then we want to examine direct paths:
-        bool examineDirectPath = lineRef->doesHateCrossings() || 
-                !(router->clusterRefs.empty());
-        
-        if ((start == src) && directEdge && (directEdge->getDist() > 0) && 
-                !examineDirectPath)
-        {
-            tar->pathNext = src;
-            directEdge->addConn(flag);
-        }
-        else
-        {
-            aStarPath(lineRef, src, tar, start);
-        }
-    }
-
-#if 0
-    for (VertInf *t = vertices.connsBegin(); t != vertices.end();
-            t = t->lstNext)
-    {
-        t->id.db_print();
-        db_printf(" -> ");
-        t->pathNext->id.db_print();
-        db_printf("\n");
-    }
-#endif
 }