diff --git a/anabatic/src/AnabaticEngine.cpp b/anabatic/src/AnabaticEngine.cpp
index a35fe28d..093a0499 100644
--- a/anabatic/src/AnabaticEngine.cpp
+++ b/anabatic/src/AnabaticEngine.cpp
@@ -606,7 +606,6 @@ namespace Anabatic {
 
   void  AnabaticEngine::ripup ( Segment* seed, Flags flags )
   {
-
     Net* net = seed->getNet();
 
     DebugSession::open( net, 112, 120 );
diff --git a/anabatic/src/AutoSegment.cpp b/anabatic/src/AutoSegment.cpp
index 07ea93a3..eb1c7fb3 100644
--- a/anabatic/src/AutoSegment.cpp
+++ b/anabatic/src/AutoSegment.cpp
@@ -233,6 +233,77 @@ namespace {
   }
 
 
+  // ---------------------------------------------------------------
+  // Class  :  "SideStack".
+
+  class SideStack {
+    public:
+                              SideStack     ( Flags direction, DbU::Unit pitch );
+             const Interval&  getSideAt     ( DbU::Unit ) const;
+      inline const Interval&  getGSide      () const;
+      inline       DbU::Unit  getGSideMin   () const;
+      inline       DbU::Unit  getGSideMax   () const;
+                   void       addGCell      ( const GCell* );
+      inline       void       restrictGSide ( const Interval& );
+                   void       show          () const;
+    private:
+      Flags                    _direction;
+      DbU::Unit                _pitch;
+      Interval                 _full;
+      Interval                 _gside;
+      map<DbU::Unit,Interval>  _sides;
+  };
+
+
+  SideStack::SideStack ( Flags direction, DbU::Unit pitch )
+    : _direction( (direction & Flags::Horizontal) ? Flags::Vertical : Flags::Horizontal )
+    , _pitch    (pitch)
+    , _full     (false)
+    , _gside    (false)
+    , _sides    ()
+  { }
+
+
+  inline const Interval&  SideStack::getGSide      () const { return _gside; }
+  inline       DbU::Unit  SideStack::getGSideMin   () const { return _gside.getVMin(); }
+  inline       DbU::Unit  SideStack::getGSideMax   () const { return _gside.getVMax(); }
+  inline       void       SideStack::restrictGSide ( const Interval& restrict ) { _gside.intersection( restrict ); }
+
+
+  const Interval& SideStack::getSideAt ( DbU::Unit position ) const
+  {
+    if (_sides.empty()) return _full;
+    if (_sides.size() == 1) return _sides.begin()->second;
+
+    if (_sides.begin()->first > position) return _sides.begin()->second;
+    for ( auto iside = ++_sides.begin() ; iside != _sides.end() ; ++iside ) {
+      if (iside->first >= position) return (--iside)->second;
+    }
+    return _sides.rbegin()->second;
+  }
+
+
+  void  SideStack::addGCell ( const GCell* gcell )
+  {
+    Interval  side     = gcell->getSide( _direction, _pitch );
+    DbU::Unit position = (_direction & Flags::Vertical) ? gcell->getBoundingBox().getXMin()
+                                                        : gcell->getBoundingBox().getYMin();
+
+    _gside.intersection( side );
+    _sides.insert( make_pair(position,side) );
+  }
+
+
+  void  SideStack::show () const
+  {
+    cdebug_log(145,0) << "SideStack::show()" << endl;
+    for ( auto pside : _sides ) {
+      cdebug_log(145,0) << "@ " << DbU::getValueString(pside.first)
+                        << " " << pside.second << endl;
+    }
+  }
+
+
 } // End of local namespace.
 
 
@@ -828,7 +899,7 @@ namespace Anabatic {
       cdebug_tabw(149,-1);
       return true;
     }
-
+    
     if (getAxis() > optimalMax) {
       setAxis( optimalMax, flags );
       cdebug_tabw(149,-1);
@@ -922,6 +993,7 @@ namespace Anabatic {
     DbU::Unit            constraintMin;
     DbU::Unit            constraintMax;
     vector<AutoSegment*> aligneds;
+    SideStack            sideStack ( (isHorizontal() ? Flags::Horizontal : Flags::Vertical), getPitch() );
   
     getConstraints( constraintMin, constraintMax );
     cdebug_log(145,0) << "Constraints: [" << DbU::getValueString(constraintMin)
@@ -931,43 +1003,37 @@ namespace Anabatic {
       optimalMin = optimalMax = getAxis();
       aligneds.push_back( this );
     } else {
-      DbU::Unit      minGCell    = getOrigin();
-      DbU::Unit      maxGCell    = getExtremity();
       DbU::Unit      terminalMin;
       DbU::Unit      terminalMax;
       AttractorsMap  attractors;
 
       Flags flags = (isAnalog() ? Flags::WithDoglegs : Flags::NoFlags);
-      Flags f2 = flags | Flags::WithSelf;
 
       getAligneds( Flags::WithSelf|flags ).fill( aligneds );
 
-      if (not getGCell()->isMatrix()) {
-        Flags          direction = (isHorizontal()) ? Flags::Vertical : Flags::Horizontal;
-        Interval       gcellSide ( false );
+      if (getGCell()->isMatrix()) {
+        sideStack.addGCell( getGCell() );
+      } else {
         vector<GCell*> gcells;
-        DbU::Unit      pitch     = getPitch();
 
-        cdebug_log(145,0) << "Using pitch for L/T shrink:" << DbU::getValueString(pitch) << endl;
+        cdebug_log(145,0) << "Using pitch for L/T shrink:" << DbU::getValueString(getPitch()) << endl;
         for ( AutoSegment* aligned : aligneds ) {
           aligned->getGCells( gcells );
           for ( GCell* gcell : gcells ) {
-            gcellSide.intersection( gcell->getSide(direction,pitch) );
-            cdebug_log(145,0) << "| gcellSide:" << gcellSide << " (from " << gcell << ")" << endl;
+            sideStack.addGCell( gcell );
+            cdebug_log(145,0) << "| gcellSide:" << sideStack.getGSide() << " (from " << gcell << ")" << endl;
           }
           if (aligned->isStrongTerminal()) {
             Interval terminalConstraints;
             aligned->getConstraints( terminalConstraints );
-            gcellSide.intersection( terminalConstraints );
-            cdebug_log(145,0) << "| gcellSide:" << gcellSide << " (from " << aligned << ")" << endl;
+            sideStack.restrictGSide( terminalConstraints );
+            cdebug_log(145,0) << "| gcellSide:" << sideStack.getGSide() << " (from " << aligned << ")" << endl;
           }
         }
-        minGCell = gcellSide.getVMin();
-        maxGCell = gcellSide.getVMax();
       }
+      sideStack.show();
 
-      cdebug_log(145,0) << "GCell interval [" << DbU::getValueString(minGCell)
-                        << ":"                << DbU::getValueString(maxGCell) << "]" << endl;
+      cdebug_log(145,0) << "GCell interval " << sideStack.getGSide() << endl;
   
       AutoContact* anchor = getAutoSource();
       if (anchor->isTerminal()) {
@@ -1006,12 +1072,19 @@ namespace Anabatic {
         if (autoSegment->isGlobal()) {
           cdebug_log(145,0) << "Used as global." << endl;
 
-        // Sloppy implentation.
-          DbU::Unit perpandMin = autoSegment->getSourceU();
-          DbU::Unit perpandMax = autoSegment->getTargetU();
+          const Interval& side = sideStack.getSideAt( autoSegment->getAxis() );
+          cdebug_log(145,0) << "Side @" << DbU::getValueString(autoSegment->getAxis())
+                            << " " << side << endl;
 
-          if (perpandMin < minGCell) attractors.addAttractor( minGCell );
-          if (perpandMax > maxGCell) attractors.addAttractor( maxGCell );
+          if (autoSegment->getSourceU() < side.getVMin()) attractors.addAttractor( sideStack.getGSideMin() );
+          if (autoSegment->getTargetU() > side.getVMax()) attractors.addAttractor( sideStack.getGSideMax() );
+
+        // // Sloppy implentation.
+        //   DbU::Unit perpandMin = autoSegment->getSourceU();
+        //   DbU::Unit perpandMax = autoSegment->getTargetU();
+
+        //   if (perpandMin < minGCell) attractors.addAttractor( minGCell );
+        //   if (perpandMax > maxGCell) attractors.addAttractor( maxGCell );
         } else if (autoSegment->isLocal()) {
           if (autoSegment->isStrongTerminal()) {
             cdebug_log(145,0) << "Used as strong terminal." << endl;
@@ -1054,8 +1127,8 @@ namespace Anabatic {
                                       : _gcell->getBoundingBox().getXMax();
       }
 
-      setInBound( minGCell, maxGCell, optimalMin );
-      setInBound( minGCell, maxGCell, optimalMax );
+      setInBound( sideStack.getGSideMin(), sideStack.getGSideMax(), optimalMin );
+      setInBound( sideStack.getGSideMin(), sideStack.getGSideMax(), optimalMax );
 
       cdebug_log(145,0) << "optimalMin: " << DbU::getValueString(optimalMin) << endl;
       cdebug_log(145,0) << "optimalMax: " << DbU::getValueString(optimalMax) << endl;
diff --git a/anabatic/src/Dijkstra.cpp b/anabatic/src/Dijkstra.cpp
index b3ad7cf7..5dbc0d1d 100644
--- a/anabatic/src/Dijkstra.cpp
+++ b/anabatic/src/Dijkstra.cpp
@@ -394,7 +394,8 @@ namespace Anabatic {
     IntervalC intervfrom = IntervalC();
 
     if (_adata == NULL){
-      cdebug_log(112,1) << "Point Vertex::getStartPathPoint( const Vertex* next ) const: GRAData unset." << endl;
+      cdebug_log(112,0) << "Point Vertex::getStartPathPoint( const Vertex* next ) const: GRAData unset." << endl;
+      cdebug_tabw(112,-1);
       return Point(0,0);
     }
 
@@ -754,6 +755,7 @@ namespace Anabatic {
 
     } else {
       cdebug_log(112,0) << "[ERROR](void Vertex::setIntervals(...)): Something is wrong." << endl;
+      cdebug_tabw(112,-1);
       return;
     }
     cdebug_log(112,0) << "IntervFrom => min: " << DbU::getValueString(min) << ", max: " << DbU::getValueString(max) << ", axis:" << DbU::getValueString(axis) << endl; 
@@ -792,7 +794,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->isiSet();
     } else {
-      cdebug_log(112,1) << "bool Vertex::isiSet() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "bool Vertex::isiSet() const: Inappropriate usage of GRAData. " <<  endl;
       return false;
     }
   }
@@ -803,7 +805,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getIAxis();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getIAxis() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getIAxis() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -814,7 +816,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getIMax();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getIMax() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getIMax() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -825,7 +827,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getIMin();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getIMin() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getIMin() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -836,7 +838,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getPIAxis();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getPIAxis() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getPIAxis() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -847,7 +849,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getPIMax();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getPIMax() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getPIMax() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -858,7 +860,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getPIMin();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getPIMin() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getPIMin() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -869,7 +871,7 @@ namespace Anabatic {
     if (_adata){
       _adata->setInterv(min, max, axis);
     } else {
-      cdebug_log(112,1) << "void Vertex::setInterv( DbU::Unit min, DbU::Unit max, DbU::Unit axis ): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::setInterv( DbU::Unit min, DbU::Unit max, DbU::Unit axis ): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -879,7 +881,7 @@ namespace Anabatic {
     if (_adata){
       _adata->setIntervfrom(min, max, axis);
     } else {
-      cdebug_log(112,1) << "void Vertex::setIntervfrom( DbU::Unit min, DbU::Unit max, DbU::Unit axis ): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::setIntervfrom( DbU::Unit min, DbU::Unit max, DbU::Unit axis ): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -889,7 +891,7 @@ namespace Anabatic {
     if (_adata){
       _adata->setIntervfrom2(min, max, axis);
     } else {
-      cdebug_log(112,1) << "void Vertex::setIntervfrom2( DbU::Unit min, DbU::Unit max, DbU::Unit axis ): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::setIntervfrom2( DbU::Unit min, DbU::Unit max, DbU::Unit axis ): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -899,7 +901,7 @@ namespace Anabatic {
     if (_adata){
       _adata->resetIntervals();
     } else {
-      cdebug_log(112,1) << "void Vertex::resetIntervals(): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::resetIntervals(): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -909,7 +911,7 @@ namespace Anabatic {
     if (_adata){
       _adata->clearFrom2();
     } else {
-      cdebug_log(112,1) << "void Vertex::clearfrom2(): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::clearfrom2(): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -919,7 +921,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getFrom2();
     } else {
-      cdebug_log(112,1) << "Edge* Vertex::getFrom2() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "Edge* Vertex::getFrom2() const: Inappropriate usage of GRAData. " <<  endl;
       return NULL;
     }
   }
@@ -930,7 +932,7 @@ namespace Anabatic {
     if (_adata){
       _adata->setFrom2(from);
     } else {
-      cdebug_log(112,1) << "void Vertex::setFrom2( Edge* from ): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::setFrom2( Edge* from ): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -940,7 +942,7 @@ namespace Anabatic {
     if (_adata){
     //_adata->createIntervFrom2();
     } else {
-      cdebug_log(112,1) << "void Vertex::createIntervFrom2(): Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::createIntervFrom2(): Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -950,7 +952,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getPIMax2();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getPIMax2() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getPIMax2() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -961,7 +963,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getPIMin2();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getPIMin2() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getPIMin2() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -972,7 +974,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getPIAxis2();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getPIAxis2() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getPIAxis2() const: Inappropriate usage of GRAData. " <<  endl;
       return 0;
     }
   }
@@ -983,7 +985,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getIntervFrom2();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getIntervFrom2() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getIntervFrom2() const: Inappropriate usage of GRAData. " <<  endl;
       return IntervalC();
     }
   }
@@ -1017,7 +1019,7 @@ namespace Anabatic {
           return _adata->getIntervFrom();
       }
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getIntervFrom(Flags criteria) const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getIntervFrom(Flags criteria) const: Inappropriate usage of GRAData. " <<  endl;
       return IntervalC();
     }
   }
@@ -1066,7 +1068,7 @@ namespace Anabatic {
     if (_adata){
       return _adata->getInterv();
     } else {
-      cdebug_log(112,1) << "DbU::Unit Vertex::getInterv() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "DbU::Unit Vertex::getInterv() const: Inappropriate usage of GRAData. " <<  endl;
       return IntervalC();
     }
   }
@@ -1077,7 +1079,7 @@ namespace Anabatic {
     if (_adata){
       _adata->printInterv();
     } else {
-      cdebug_log(112,1) << "void Vertex::printInterv() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::printInterv() const: Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
@@ -1087,7 +1089,7 @@ namespace Anabatic {
     if (_adata){
       _adata->printIntervfrom();
     } else {
-      cdebug_log(112,1) << "void Vertex::printIntervfrom() const: Inappropriate usage of GRAData. " <<  endl;
+      cdebug_log(112,0) << "void Vertex::printIntervfrom() const: Inappropriate usage of GRAData. " <<  endl;
     }
   }
 
diff --git a/katana/src/DataSymmetric.cpp b/katana/src/DataSymmetric.cpp
index 2524a1d4..aaf69f69 100644
--- a/katana/src/DataSymmetric.cpp
+++ b/katana/src/DataSymmetric.cpp
@@ -167,12 +167,13 @@ namespace Katana {
               _valid = false;
             }
 
-            if (std::abs( 2*getSymAxis() - paired[0]->getAxis() - paired[1]->getAxis() ) > 2*vPitch ) {
+            if (std::abs( 2*getSymAxis() - paired[0]->getAxis() - paired[1]->getAxis() ) > 5*vPitch ) {
               errors.newline() << "Mirror axis mismatch @ [" << index << "] "
                                << DbU::getValueString(paired[1]->getAxis()) << " (should be: "
                                << DbU::getValueString(2*getSymAxis() - paired[0]->getAxis()) << ")";
               errors.newline() << "| " << paired[0];
               errors.newline() << "| " << paired[1];
+              errors.newline() << "| Tolerance (5*vPitch): " << DbU::getValueString(5*vPitch);
               _valid = false;
             }
           } else {
@@ -184,32 +185,35 @@ namespace Katana {
               _valid = false;
             }
 
-            if ( std::abs( paired[0]->getAxis() - paired[1]->getAxis() ) > 2*hPitch ) {
+            if ( std::abs( paired[0]->getAxis() - paired[1]->getAxis() ) > 5*hPitch ) {
               errors.newline() << "Axis mismatch index " << index << " "
                                << DbU::getValueString(paired[1]->getAxis()) << " (should be:"
                                << DbU::getValueString(paired[0]->getAxis()) << ")";
               errors.newline() << "| " << paired[0];
               errors.newline() << "| " << paired[1];
+              errors.newline() << "| Tolerance (5*hPitch): " << DbU::getValueString(5*hPitch);
               _valid = false;
             }
           }
         } else {
           if (paired[0]->isHorizontal()) {
-            if ( std::abs( 2*getSymAxis() - paired[0]->getAxis() - paired[1]->getAxis() ) > 2*hPitch ) {
+            if ( std::abs( 2*getSymAxis() - paired[0]->getAxis() - paired[1]->getAxis() ) > 5*hPitch ) {
               errors.newline() << "Mirror axis mismatch index " << index << " "
                                << DbU::getValueString(paired[1]->getAxis()) << " (should be:"
                                << DbU::getValueString(2*getSymAxis() - paired[0]->getAxis()) << ")";
               errors.newline() << "| " << paired[0];
               errors.newline() << "| " << paired[1];
+              errors.newline() << "| Tolerance (5*hPitch): " << DbU::getValueString(5*hPitch);
               _valid = false;
             }
           } else {
-            if ( std::abs( paired[0]->getAxis() != paired[1]->getAxis() ) > 2*vPitch ) {
+            if ( std::abs( paired[0]->getAxis() != paired[1]->getAxis() ) > 5*vPitch ) {
               errors.newline() << "Axis mismatch index " << index << " "
                                << DbU::getValueString(paired[1]->getAxis()) << " (should be:"
                                << DbU::getValueString(paired[0]->getAxis()) << ")";
               errors.newline() << "| " << paired[0];
               errors.newline() << "| " << paired[1];
+              errors.newline() << "| Tolerance (5*vPitch): " << DbU::getValueString(5*vPitch);
               _valid = false;
             }
           }
diff --git a/katana/src/KatanaEngine.cpp b/katana/src/KatanaEngine.cpp
index a752861f..d5ccc604 100644
--- a/katana/src/KatanaEngine.cpp
+++ b/katana/src/KatanaEngine.cpp
@@ -54,6 +54,9 @@ namespace {
   using Hurricane::NetRoutingExtension;
   using Hurricane::Net;
   using Hurricane::Cell;
+  using Hurricane::Segment;
+  using Katana::Session;
+  using Katana::TrackSegment;
 
 
   void  setSymmetricSelf ( Cell* cell, string name )
@@ -562,7 +565,7 @@ namespace Katana {
     addMeasure<unsigned long long>( getCell(), "DWL(l)" , totalWireLength                  , 12 );
     addMeasure<unsigned long long>( getCell(), "fWL(l)" , totalWireLength-routedWireLength , 12 );
     addMeasure<double>            ( getCell(), "WLER(%)", (expandRatio-1.0)*100.0 );
-}
+  }
 
 
   void  KatanaEngine::dumpMeasures ( ostream& out ) const
diff --git a/katana/src/NegociateWindow.cpp b/katana/src/NegociateWindow.cpp
index 20d4b396..d09ea9cb 100644
--- a/katana/src/NegociateWindow.cpp
+++ b/katana/src/NegociateWindow.cpp
@@ -18,6 +18,7 @@
 #include <algorithm>
 #include <fstream>
 #include <iomanip>
+#include "hurricane/DebugSession.h"
 #include "hurricane/Warning.h"
 #include "hurricane/Bug.h"
 #include "hurricane/RoutingPad.h"
@@ -133,6 +134,38 @@ namespace {
   }
 
 
+  class CompareByPriority {
+    public:
+      inline bool operator() ( const TrackSegment* lhs, const TrackSegment* rhs )
+      { return lhs->getPriority() > rhs->getPriority(); }
+  };
+ 
+
+  void  computeNetPriority ( Net* net )
+  {
+    DebugSession::open( net, 159, 160 );
+
+    cdebug_log(159,1) << "::computeNetPriority() " << net << endl;
+
+    vector<TrackSegment*> segments;
+    for ( Segment* segment : net->getSegments() ) {
+      TrackSegment* canonical = dynamic_cast<TrackSegment*>( Session::lookup( segment ) );
+      if (canonical) segments.push_back( canonical );
+    }
+
+    for ( TrackSegment* segment : segments ) segment->computePriority();
+    sort( segments.begin(), segments.end(), CompareByPriority() );
+
+    for ( TrackSegment* segment : segments ) {
+      segment->computeAlignedPriority();
+    }
+
+    cdebug_tabw(159,-1);
+
+    DebugSession::close();
+  }
+
+
 } // Anonymous namespace.
 
 
@@ -149,6 +182,7 @@ namespace Katana {
   using Hurricane::Bug;
   using Hurricane::tab;
   using Hurricane::ForEachIterator;
+  using Hurricane::DebugSession;
   using CRL::Histogram;
   using CRL::addMeasure;
   using Anabatic::AutoContact;
@@ -343,6 +377,14 @@ namespace Katana {
   }
 
 
+  void  NegociateWindow::_computePriorities ()
+  {
+    for ( Net* net : getCell()->getNets() ) {
+      if (NetRoutingExtension::isAnalog(net)) computeNetPriority( net );
+    }
+  }
+
+
   void  NegociateWindow::_createRouting  ( Anabatic::GCell* gcell )
   {
     cdebug_log(159,1) << "NegociateWindow::_createRouting() - " << gcell << endl;
@@ -561,6 +603,7 @@ namespace Katana {
       _createRouting( _gcells[igcell] );
     }
     Session::revalidate();
+    _computePriorities();
 
     if (not (flags & Flags::PreRoutedStage)) {
       _katana->preProcess();
diff --git a/katana/src/RoutingEvent.cpp b/katana/src/RoutingEvent.cpp
index 865c3846..ec7a3ef2 100644
--- a/katana/src/RoutingEvent.cpp
+++ b/katana/src/RoutingEvent.cpp
@@ -655,7 +655,7 @@ namespace Katana {
                            and _segment->base()->getAutoTarget()->isTerminal();
     }
 
-    _segment->updatePriority();
+    _segment->computePriority();
 
     cdebug_log(159,0) << _segment << " has " << (int)_tracksNb << " choices " << perpandicular << endl;
     cdebug_tabw(159,-1);
diff --git a/katana/src/SegmentFsm.cpp b/katana/src/SegmentFsm.cpp
index 08ebe923..26053225 100644
--- a/katana/src/SegmentFsm.cpp
+++ b/katana/src/SegmentFsm.cpp
@@ -570,6 +570,7 @@ namespace Katana {
     for ( Track* track1 : Tracks_Range::get(plane,_constraint) ) {
       uint32_t costflags = 0;
       costflags |= (segment1->isLocal() and (depth >= 3)) ? TrackCost::LocalAndTopDepth : 0;
+      costflags |= (segment1->isAnalog()) ? TrackCost::Analog : 0;
 
       Track* track2 = NULL;
       if (_event2) {
diff --git a/katana/src/Session.cpp b/katana/src/Session.cpp
index 0f543dd0..fe6df948 100644
--- a/katana/src/Session.cpp
+++ b/katana/src/Session.cpp
@@ -226,9 +226,10 @@ namespace Katana {
         cdebug_log(159,0) << "Session: reduce:" << revalidateds[i] << endl;
       }
       if (revalidateds[i]->mustRaise()) {
-        revalidateds[i]->raise();
-        lookup( revalidateds[i] )->reschedule( 0 );
         cdebug_log(159,0) << "Session: raise:" << revalidateds[i] << endl;
+        revalidateds[i]->raise();
+        TrackElement* trackSegment = lookup( revalidateds[i] );
+        if (trackSegment) trackSegment->reschedule( 0 );
       }
     }
 
diff --git a/katana/src/TrackCost.cpp b/katana/src/TrackCost.cpp
index 57a04d86..e173ede2 100644
--- a/katana/src/TrackCost.cpp
+++ b/katana/src/TrackCost.cpp
@@ -91,34 +91,36 @@ namespace Katana {
     , _dataState      (0)
     , _ripupCount     (0)
   {
-  // This is the GCell side (it is *one* cell height from the gauge).
-    DbU::Unit  cellHeight = Session::getSliceHeight();
+    if (not (_flags & Analog)) {
+    // This is the GCell side (it is *one* cell height from the gauge).
+      DbU::Unit  cellHeight = Session::getSliceHeight();
 
-    TrackElement* neighbor;
-    if ( _begin != Track::npos ) {
-      neighbor = _track->getSegment(_begin);
-      if ( neighbor and (neighbor->getNet() != net) ) {
-        DbU::Unit distance = interval.getVMin() - neighbor->getTargetU();
-        if ( distance < cellHeight )
-          _distanceToFixed = distance;
-      }
+      TrackElement* neighbor;
+      if ( _begin != Track::npos ) {
+        neighbor = _track->getSegment(_begin);
+        if ( neighbor and (neighbor->getNet() != net) ) {
+          DbU::Unit distance = interval.getVMin() - neighbor->getTargetU();
+          if ( distance < cellHeight )
+            _distanceToFixed = distance;
+        }
       // if ( neighbor and neighbor->isFixed() ) {
       //   if ( _distanceToFixed == DbU::Max ) _distanceToFixed = 0;
       //   _distanceToFixed += interval.getVMin() - neighbor->getTargetU();
       // }
-    }
-    if ( _end != Track::npos ) {
-      neighbor = _track->getSegment(_end);
-      if ( neighbor and (neighbor->getNet() != net) ) {
-        DbU::Unit distance = neighbor->getSourceU() - interval.getVMax();
-        if ( _distanceToFixed == 2*cellHeight ) _distanceToFixed = 0;
-        if ( distance < cellHeight )
-          _distanceToFixed += distance;
       }
+      if ( _end != Track::npos ) {
+        neighbor = _track->getSegment(_end);
+        if ( neighbor and (neighbor->getNet() != net) ) {
+          DbU::Unit distance = neighbor->getSourceU() - interval.getVMax();
+          if ( _distanceToFixed == 2*cellHeight ) _distanceToFixed = 0;
+          if ( distance < cellHeight )
+            _distanceToFixed += distance;
+        }
       // if ( neighbor and neighbor->isFixed() ) {
       //   if ( _distanceToFixed == DbU::Max ) _distanceToFixed = 0;
       //   _distanceToFixed += neighbor->getSourceU() - interval.getVMax();
       // }
+      }
     }
   }
 
@@ -162,12 +164,14 @@ namespace Katana {
 
     if (lhs._delta != rhs._delta) {
     //cdebug_log(155,0) << "TrackCost::Compare() lhs._delta:" << lhs._delta << " rhs._delta:" << rhs._delta << endl;
-      if ( not (_flags & TrackCost::IgnoreSharedLength) or (lhs._delta > 0) or (rhs._delta > 0) ) {
+    //if ( not (_flags & TrackCost::IgnoreSharedLength) or (lhs._delta > 0) or (rhs._delta > 0) ) {
     //if ( (lhs._delta > 0) or (rhs._delta > 0) ) {
         if (lhs._delta < rhs._delta) return true;
         if (lhs._delta > rhs._delta) return false;
-      }
+    //}
 
+    // Both delta should be negative, chose the least one.
+    //return lhs._delta > rhs._delta;
       return lhs._delta < rhs._delta;
     }
 
@@ -210,8 +214,9 @@ namespace Katana {
     if ( not _infinite and not _hardOverlap ) {
       cdebug_log(159,0) << "TrackCost::consolidate() " << _delta << " - " << _deltaShared << endl;
     //_deltaPerpand += - (_deltaShared << 1);
-      _delta += - _deltaShared;
-    //_delta += _deltaShared;
+      _delta -= _deltaShared;
+    //if (_delta > 0) _delta -= _deltaShared;
+    //else            _delta += _deltaShared;
     }
   }
 
@@ -249,7 +254,7 @@ namespace Katana {
     s += "-" + /*DbU::getValueString(_deltaShared)*/ getString(_deltaShared);
     s += "/" + DbU::getValueString(_axisWeight);
     s += "/" + DbU::getValueString(_deltaPerpand);
-    s += "/" + DbU::getValueString(_distanceToFixed);
+    s += "/f:" + DbU::getValueString(_distanceToFixed);
     s += "/" + DbU::getValueString(_longuestOverlap);
     s += " " + getString(_dataState);
     s += ">";
diff --git a/katana/src/TrackElement.cpp b/katana/src/TrackElement.cpp
index 2b28774b..c36399d9 100644
--- a/katana/src/TrackElement.cpp
+++ b/katana/src/TrackElement.cpp
@@ -144,6 +144,7 @@ namespace Katana {
   bool           TrackElement::isReduced            () const { return false; }
   bool           TrackElement::isUTurn              () const { return false; }
   bool           TrackElement::isUserDefined        () const { return false; }
+  bool           TrackElement::isAnalog             () const { return false; }
 // Predicates.
   bool           TrackElement::hasSymmetric         () const { return false; }
   bool           TrackElement::canSlacken           () const { return false; }
diff --git a/katana/src/TrackFixedSegment.cpp b/katana/src/TrackFixedSegment.cpp
index fb465ce6..dd763853 100644
--- a/katana/src/TrackFixedSegment.cpp
+++ b/katana/src/TrackFixedSegment.cpp
@@ -130,15 +130,16 @@ namespace Katana {
   }
 
 
-  AutoSegment*   TrackFixedSegment::base            () const { return NULL; }
-  Segment*       TrackFixedSegment::getSegment      () const { return _segment; }
-  DbU::Unit      TrackFixedSegment::getAxis         () const { return getTrack()->getAxis(); }
-  bool           TrackFixedSegment::isHorizontal    () const { return getTrack()->isHorizontal(); }
-  bool           TrackFixedSegment::isVertical      () const { return getTrack()->isVertical(); }
-  bool           TrackFixedSegment::isFixed         () const { return true; }
-  Flags          TrackFixedSegment::getDirection    () const { return getTrack()->getDirection(); }
-  const Layer*   TrackFixedSegment::getLayer        () const { return _segment->getLayer(); }
-  Interval       TrackFixedSegment::getFreeInterval () const { return Interval(); }
+  AutoSegment*   TrackFixedSegment::base             () const { return NULL; }
+  Segment*       TrackFixedSegment::getSegment       () const { return _segment; }
+  DbU::Unit      TrackFixedSegment::getAxis          () const { return getTrack()->getAxis(); }
+  bool           TrackFixedSegment::isHorizontal     () const { return getTrack()->isHorizontal(); }
+  bool           TrackFixedSegment::isVertical       () const { return getTrack()->isVertical(); }
+  bool           TrackFixedSegment::isFixed          () const { return true; }
+  bool           TrackFixedSegment::isPriorityLocked () const { return false; }
+  Flags          TrackFixedSegment::getDirection     () const { return getTrack()->getDirection(); }
+  const Layer*   TrackFixedSegment::getLayer         () const { return _segment->getLayer(); }
+  Interval       TrackFixedSegment::getFreeInterval  () const { return Interval(); }
 
 
   unsigned long  TrackFixedSegment::getId () const
@@ -175,7 +176,19 @@ namespace Katana {
   { return 0.0; }
 
 
-  void  TrackFixedSegment::updatePriority ( float )
+  void  TrackFixedSegment::setPriorityLock ( bool )
+  { }
+
+
+  void  TrackFixedSegment::forcePriority ( float )
+  { }
+
+
+  void  TrackFixedSegment::computePriority ()
+  { }
+
+
+  void  TrackFixedSegment::computeAlignedPriority ()
   { }
 
 
diff --git a/katana/src/TrackSegment.cpp b/katana/src/TrackSegment.cpp
index 6cf9628f..2554e2d2 100644
--- a/katana/src/TrackSegment.cpp
+++ b/katana/src/TrackSegment.cpp
@@ -67,6 +67,7 @@ namespace Katana {
     , _data         (NULL)
     , _priority     (0.0)
     , _dogLegLevel  (0)
+    , _flags        (NoFlags)
   {
     cdebug_log(155,0) << "CTOR TrackSegment " << (void*)this    << ":" << this    << endl;
     cdebug_log(155,0) << "             over " << (void*)segment << ":" << segment << endl;
@@ -162,6 +163,8 @@ namespace Katana {
   bool           TrackSegment::isReduced            () const { return _base->isReduced(); }
   bool           TrackSegment::isUserDefined        () const { return _base->isUserDefined(); }
   bool           TrackSegment::isUTurn              () const { return _base->isUTurn(); }
+  bool           TrackSegment::isAnalog             () const { return _base->isAnalog(); }
+  bool           TrackSegment::isPriorityLocked     () const { return _flags & PriorityLocked; }
 // Predicates.
   bool           TrackSegment::hasSymmetric         () const { return _symmetric != NULL; }
 // Accessors.
@@ -305,22 +308,38 @@ namespace Katana {
   }
 
 
+  void  TrackSegment::setPriorityLock ( bool state )
+  {
+    if (state) _flags |=  PriorityLocked;
+    else       _flags &= ~PriorityLocked;
+  }
+
+
   void  TrackSegment::updateFreedomDegree ()
   { _freedomDegree = _base->getSlack(); }
 
 
-  void  TrackSegment::updatePriority ( float forced )
+  void  TrackSegment::forcePriority ( float forced )
+  { if (not isPriorityLocked()) _priority = forced; }
+
+
+  void  TrackSegment::computePriority ()
   {
-    if (forced != 0.0) { _priority = forced; return; }
+    if (isPriorityLocked()) return;
+    if (isAnalog() and isTerminal()) { _priority = 0.0; return; }
 
     double length = DbU::toLambda(getLength());
     double slack  = DbU::toLambda(base()->getSlack());
+    double pitch  = DbU::toLambda(getPitch());
 
   //if (length > 200.0) length = 200.0 - std::log(length)*20.0;
   //if (length <   0.0) length =   0.0;
   //if (slack / DbU::toLambda(_segment->getPitch()) < 2.0 ) slack = 999.0;
-    if (slack / DbU::toLambda(getPitch()) > 10.0) slack = 10.0*getPitch();
+    if (slack / pitch > 10.0) slack = 10.0*pitch;
       
+  //cerr << "TrackSegment::computePriority() length:" << length << " slack:" << slack
+  //     << " pri:" << (length + 1.0) * (slack + 1.0) << " pitch:" << DbU::toLambda(getPitch()) << endl;
+
     _priority = (length + 1.0) * (slack + 1.0);
 
   //if (_priority > 10000.0) cerr << "_priority:" << _priority
@@ -431,6 +450,48 @@ namespace Katana {
   }
 
 
+  void  TrackSegment::computeAlignedPriority ()
+  {
+    if (isPriorityLocked() or isTerminal()) return;
+
+    computePriority();
+
+    AutoSegment* canonical = base();
+
+    vector<TrackElement*> sourceAligneds;
+    vector<TrackElement*> targetAligneds;
+    for ( AutoSegment* segment : canonical->getAligneds(Flags::Source|Flags::WithDoglegs) ) {
+      if (not segment->isCanonical()) continue;
+      sourceAligneds.push_back( Session::lookup(segment) );
+    }
+    for ( AutoSegment* segment : canonical->getAligneds(Flags::Target|Flags::WithDoglegs) ) {
+      if (not segment->isCanonical()) continue;
+      sourceAligneds.push_back( Session::lookup(segment) );
+    }
+
+    if (sourceAligneds.empty() and targetAligneds.empty()) return;
+
+    setPriorityLock( true );
+
+    cdebug_log(159,0) << "TrackSegment::computeAlignedPriority() " << this << endl;
+    cdebug_log(159,0) << "Aligneds on:" << getPriority() << ":" << this << endl;
+    for ( size_t i=0 ; i<sourceAligneds.size() ; ++i ) {
+      sourceAligneds[i]->forcePriority( getPriority() - 2.0*(i+1) + 1.0 );
+      sourceAligneds[i]->setPriorityLock( true );
+
+      cdebug_log(159,0) << "| S:" << i << " " << sourceAligneds[i]->getPriority()
+                        << ":" << sourceAligneds[i] << endl;
+    }
+    for ( size_t i=0 ; i<targetAligneds.size() ; ++i ) {
+      targetAligneds[i]->forcePriority( getPriority() - 2.0*(i+1) );
+      targetAligneds[i]->setPriorityLock( true );
+
+      cdebug_log(159,0) << "| T:" << i << " " << targetAligneds[i]->getPriority()
+                        << ":" << targetAligneds[i] << endl;
+    }
+  }
+
+
   float  TrackSegment::getMaxUnderDensity ( Flags flags ) const
   { return _base->getMaxUnderDensity( flags ); }
 
@@ -911,6 +972,7 @@ namespace Katana {
     Record* record = TrackElement::_getRecord();
     record->add( getSlot( "_base"     ,  _base      ) );
     record->add( getSlot( "_symmetric",  _symmetric ) );
+    record->add( getSlot( "_flags"    ,  _flags     ) );
     return record;
   }
 
diff --git a/katana/src/katana/NegociateWindow.h b/katana/src/katana/NegociateWindow.h
index 0a35dcdd..22350714 100644
--- a/katana/src/katana/NegociateWindow.h
+++ b/katana/src/katana/NegociateWindow.h
@@ -115,6 +115,7 @@ namespace Katana {
              void                          run                  ( Flags flags );
              void                          printStatistics      () const;
              void                          _createRouting       ( Anabatic::GCell* );
+             void                          _computePriorities   ();
              void                          _associateSymmetrics ();
              void                          _pack                ( size_t& count, bool last );
              size_t                        _negociate           ();
diff --git a/katana/src/katana/TrackCost.h b/katana/src/katana/TrackCost.h
index eba1e076..c0ba9ff3 100644
--- a/katana/src/katana/TrackCost.h
+++ b/katana/src/katana/TrackCost.h
@@ -39,11 +39,12 @@ namespace Katana {
  
   class TrackCost {
     public:
-      enum Flags { IgnoreAxisWeight   = 0x0001
-                 , DiscardGlobals     = 0x0002
-                 , IgnoreSharedLength = 0x0004
-                 , LocalAndTopDepth   = 0x0008
-                 , ZeroCost           = 0x0010
+      enum Flags { IgnoreAxisWeight   = (1 << 0)
+                 , DiscardGlobals     = (1 << 1)
+                 , IgnoreSharedLength = (1 << 2)
+                 , LocalAndTopDepth   = (1 << 3)
+                 , ZeroCost           = (1 << 4)
+                 , Analog             = (1 << 5)
                  };
 
     public:
diff --git a/katana/src/katana/TrackElement.h b/katana/src/katana/TrackElement.h
index 692e9be0..b89691fe 100644
--- a/katana/src/katana/TrackElement.h
+++ b/katana/src/katana/TrackElement.h
@@ -84,112 +84,116 @@ namespace Katana {
   class TrackElement {
 
     public:
-      static  SegmentOverlapCostCB*   setOverlapCostCB     ( SegmentOverlapCostCB* );
-      static  void                    notify               ( TrackElement*, unsigned int flags );
-    public:                                                
-              void                    destroy              ();
-      virtual AutoSegment*            base                 () const;
-      virtual Segment*                getSegment           () const = 0;
-    // Wrapped AutoSegment Functions (when applicable).
-      virtual bool                    isFixed              () const;
-      virtual bool                    isHorizontal         () const = 0;
-      virtual bool                    isVertical           () const = 0;
-      virtual bool                    isLocal              () const;
-      virtual bool                    isGlobal             () const;
-      virtual bool                    isBipoint            () const;
-      virtual bool                    isTerminal           () const;
-      virtual bool                    isStrongTerminal     ( Flags flags=Flags::NoFlags ) const;
-      virtual bool                    isStrap              () const;
-      virtual bool                    isSlackened          () const;
-      virtual bool                    isDogleg             () const;
-      virtual bool                    isReduced            () const;
-      virtual bool                    isUTurn              () const;
-      virtual bool                    isUserDefined        () const;
-    // Predicates.                    
-      inline  bool                    isCreated            () const;
-      inline  bool                    isInvalidated        () const;
-      inline  bool                    isBlockage           () const;
-      inline  bool                    isLocked             () const;
-      inline  bool                    isRouted             () const;
-      virtual bool                    hasSymmetric         () const;
-      inline  bool                    hasSourceDogleg      () const;
-      inline  bool                    hasTargetDogleg      () const;
-      inline  bool                    canRipple            () const;
-      virtual bool                    canSlacken           () const;
-      virtual bool                    canPivotUp           ( float reserve, Flags flags ) const;
-      virtual bool                    canPivotDown         ( float reserve, Flags flags ) const;
-      virtual bool                    canMoveUp            ( float reserve, Flags flags=Flags::WithPerpands ) const;
-      virtual bool                    canDogleg            ();
-      virtual bool                    canDogleg            ( Interval );
-      virtual bool                    canDogleg            ( Anabatic::GCell*, Flags flags=0 );
-    // Accessors
-      inline  Observer<TrackElement>* getObserver          ();
-      virtual unsigned long           getId                () const;
-      virtual Flags                   getDirection         () const = 0;
-      virtual Net*                    getNet               () const = 0;
-      virtual const Layer*            getLayer             () const = 0;
-      virtual DbU::Unit               getPitch             () const;
-      virtual DbU::Unit               getPPitch            () const;
-      inline  Track*                  getTrack             () const;
-      inline  size_t                  getIndex             () const;
-      virtual float                   getPriority          () const = 0;
-      virtual unsigned long           getFreedomDegree     () const;
-      virtual float                   getMaxUnderDensity   ( Flags flags=Flags::NoFlags ) const;
-      inline  Box                     getBoundingBox       () const;
-      virtual TrackElement*           getNext              () const;
-      virtual TrackElement*           getPrevious          () const;
-      virtual DbU::Unit               getAxis              () const = 0;
-      inline  DbU::Unit               getSourceU           () const;
-      inline  DbU::Unit               getTargetU           () const;
-      inline  DbU::Unit               getLength            () const;
-      inline  Interval                getCanonicalInterval () const;
-      virtual Interval                getFreeInterval      () const;
-      virtual Interval                getSourceConstraints () const;
-      virtual Interval                getTargetConstraints () const;
-      virtual DataNegociate*          getDataNegociate     ( Flags flags=Flags::DataSelf ) const;
-      virtual TrackElement*           getCanonical         ( Interval& );
-      virtual size_t                  getGCells            ( vector<GCell*>& ) const;
-      virtual TrackElement*           getParent            () const;
-      virtual uint32_t                getDoglegLevel       () const;
-      virtual TrackElement*           getSourceDogleg      ();
-      virtual TrackElement*           getTargetDogleg      ();
-      virtual TrackElement*           getSymmetric         ();
-      virtual TrackElements           getPerpandiculars    ();
-    // Mutators.                       
-      inline  void                    setFlags             ( uint32_t );
-      inline  void                    unsetFlags           ( uint32_t );
-      inline  void                    setRouted            ();
-      virtual void                    setTrack             ( Track* );
-      inline  void                    setIndex             ( size_t );
-      virtual void                    setSymmetric         ( TrackElement* );
-      inline  void                    updatePriority       ();
-      virtual void                    updatePriority       ( float priority ) = 0;
-      virtual void                    updateFreedomDegree  ();
-      virtual void                    setDoglegLevel       ( uint32_t );
-      virtual void                    swapTrack            ( TrackElement* );
-      virtual void                    reschedule           ( uint32_t level );
-      virtual void                    detach               ();
-      virtual void                    invalidate           ();
-      virtual void                    revalidate           ();
-      virtual void                    updatePPitch         ();
-      virtual void                    incOverlapCost       ( Net*, TrackCost& ) const;
-      virtual void                    setAxis              ( DbU::Unit, uint32_t flags=Anabatic::SegAxisSet );
-      virtual TrackElement*           makeDogleg           ();
-      inline  bool                    makeDogleg           ( Anabatic::GCell* );
-      virtual TrackElement*           makeDogleg           ( Anabatic::GCell*, TrackElement*& perpandicular, TrackElement*& parallel );
-      virtual TrackElement*           makeDogleg           ( Interval, Flags& flags );
-      virtual void                    _postDoglegs         ( TrackElement*& perpandicular, TrackElement*& parallel );
-      virtual bool                    moveAside            ( Flags flags );
-      virtual bool                    slacken              ( Flags flags=Flags::NoFlags );
-      virtual bool                    moveUp               ( Flags flags );
-      virtual bool                    moveDown             ( Flags flags );
-#if THIS_IS_DISABLED                  
-      virtual void                    desalignate          ();
-#endif                                
-      virtual bool                    _check               () const;
-      virtual Record*                 _getRecord           () const;
-      virtual string                  _getString           () const;
-      virtual string                  _getTypeName         () const;
+      static  SegmentOverlapCostCB*   setOverlapCostCB       ( SegmentOverlapCostCB* );
+      static  void                    notify                 ( TrackElement*, unsigned int flags );
+    public:                                                  
+              void                    destroy                ();
+      virtual AutoSegment*            base                   () const;
+      virtual Segment*                getSegment             () const = 0;
+    // Wrapped AutoSegment Functions (when applicable).      
+      virtual bool                    isFixed                () const;
+      virtual bool                    isHorizontal           () const = 0;
+      virtual bool                    isVertical             () const = 0;
+      virtual bool                    isLocal                () const;
+      virtual bool                    isGlobal               () const;
+      virtual bool                    isBipoint              () const;
+      virtual bool                    isTerminal             () const;
+      virtual bool                    isStrongTerminal       ( Flags flags=Flags::NoFlags ) const;
+      virtual bool                    isStrap                () const;
+      virtual bool                    isSlackened            () const;
+      virtual bool                    isDogleg               () const;
+      virtual bool                    isReduced              () const;
+      virtual bool                    isUTurn                () const;
+      virtual bool                    isUserDefined          () const;
+      virtual bool                    isAnalog               () const;
+      virtual bool                    isPriorityLocked       () const = 0;
+    // Predicates.                                           
+      inline  bool                    isCreated              () const;
+      inline  bool                    isInvalidated          () const;
+      inline  bool                    isBlockage             () const;
+      inline  bool                    isLocked               () const;
+      inline  bool                    isRouted               () const;
+      virtual bool                    hasSymmetric           () const;
+      inline  bool                    hasSourceDogleg        () const;
+      inline  bool                    hasTargetDogleg        () const;
+      inline  bool                    canRipple              () const;
+      virtual bool                    canSlacken             () const;
+      virtual bool                    canPivotUp             ( float reserve, Flags flags ) const;
+      virtual bool                    canPivotDown           ( float reserve, Flags flags ) const;
+      virtual bool                    canMoveUp              ( float reserve, Flags flags=Flags::WithPerpands ) const;
+      virtual bool                    canDogleg              ();
+      virtual bool                    canDogleg              ( Interval );
+      virtual bool                    canDogleg              ( Anabatic::GCell*, Flags flags=0 );
+    // Accessors                                             
+      inline  Observer<TrackElement>* getObserver            ();
+      virtual unsigned long           getId                  () const;
+      virtual Flags                   getDirection           () const = 0;
+      virtual Net*                    getNet                 () const = 0;
+      virtual const Layer*            getLayer               () const = 0;
+      virtual DbU::Unit               getPitch               () const;
+      virtual DbU::Unit               getPPitch              () const;
+      inline  Track*                  getTrack               () const;
+      inline  size_t                  getIndex               () const;
+      virtual float                   getPriority            () const = 0;
+      virtual unsigned long           getFreedomDegree       () const;
+      virtual float                   getMaxUnderDensity     ( Flags flags=Flags::NoFlags ) const;
+      inline  Box                     getBoundingBox         () const;
+      virtual TrackElement*           getNext                () const;
+      virtual TrackElement*           getPrevious            () const;
+      virtual DbU::Unit               getAxis                () const = 0;
+      inline  DbU::Unit               getSourceU             () const;
+      inline  DbU::Unit               getTargetU             () const;
+      inline  DbU::Unit               getLength              () const;
+      inline  Interval                getCanonicalInterval   () const;
+      virtual Interval                getFreeInterval        () const;
+      virtual Interval                getSourceConstraints   () const;
+      virtual Interval                getTargetConstraints   () const;
+      virtual DataNegociate*          getDataNegociate       ( Flags flags=Flags::DataSelf ) const;
+      virtual TrackElement*           getCanonical           ( Interval& );
+      virtual size_t                  getGCells              ( vector<GCell*>& ) const;
+      virtual TrackElement*           getParent              () const;
+      virtual uint32_t                getDoglegLevel         () const;
+      virtual TrackElement*           getSourceDogleg        ();
+      virtual TrackElement*           getTargetDogleg        ();
+      virtual TrackElement*           getSymmetric           ();
+      virtual TrackElements           getPerpandiculars      ();
+    // Mutators.                                             
+      inline  void                    setFlags               ( uint32_t );
+      inline  void                    unsetFlags             ( uint32_t );
+      inline  void                    setRouted              ();
+      virtual void                    setTrack               ( Track* );
+      inline  void                    setIndex               ( size_t );
+      virtual void                    setSymmetric           ( TrackElement* );
+      virtual void                    setPriorityLock        ( bool state ) = 0;
+      virtual void                    forcePriority          ( float priority ) = 0;
+      virtual void                    computePriority        () = 0;
+      virtual void                    computeAlignedPriority () = 0;
+      virtual void                    updateFreedomDegree    ();
+      virtual void                    setDoglegLevel         ( uint32_t );
+      virtual void                    swapTrack              ( TrackElement* );
+      virtual void                    reschedule             ( uint32_t level );
+      virtual void                    detach                 ();
+      virtual void                    invalidate             ();
+      virtual void                    revalidate             ();
+      virtual void                    updatePPitch           ();
+      virtual void                    incOverlapCost         ( Net*, TrackCost& ) const;
+      virtual void                    setAxis                ( DbU::Unit, uint32_t flags=Anabatic::SegAxisSet );
+      virtual TrackElement*           makeDogleg             ();
+      inline  bool                    makeDogleg             ( Anabatic::GCell* );
+      virtual TrackElement*           makeDogleg             ( Anabatic::GCell*, TrackElement*& perpandicular, TrackElement*& parallel );
+      virtual TrackElement*           makeDogleg             ( Interval, Flags& flags );
+      virtual void                    _postDoglegs           ( TrackElement*& perpandicular, TrackElement*& parallel );
+      virtual bool                    moveAside              ( Flags flags );
+      virtual bool                    slacken                ( Flags flags=Flags::NoFlags );
+      virtual bool                    moveUp                 ( Flags flags );
+      virtual bool                    moveDown               ( Flags flags );
+#if THIS_IS_DISABLED                                         
+      virtual void                    desalignate            ();
+#endif                                                       
+      virtual bool                    _check                 () const;
+      virtual Record*                 _getRecord             () const;
+      virtual string                  _getString             () const;
+      virtual string                  _getTypeName           () const;
 
     protected:
     // Static Attributes.
@@ -234,7 +238,6 @@ namespace Katana {
   inline DbU::Unit               TrackElement::getTargetU           () const { return _targetU; }
   inline Interval                TrackElement::getCanonicalInterval () const { return Interval(getSourceU(),getTargetU()); }
   inline void                    TrackElement::setIndex             ( size_t index ) { _index=index; }
-  inline void                    TrackElement::updatePriority       () { updatePriority( 0.0 ); }
 
   inline void  TrackElement::setRouted()
   {
diff --git a/katana/src/katana/TrackFixedSegment.h b/katana/src/katana/TrackFixedSegment.h
index b9772cee..b5f623f3 100644
--- a/katana/src/katana/TrackFixedSegment.h
+++ b/katana/src/katana/TrackFixedSegment.h
@@ -38,26 +38,30 @@ namespace Katana {
 
   class TrackFixedSegment : public TrackElement {
     public:
-      static  TrackElement*  create             ( Katana::Track* track , Segment* segment );
-    public:
-      virtual AutoSegment*   base               () const;
-      virtual Segment*       getSegment         () const;
-      virtual bool           isHorizontal       () const;
-      virtual bool           isVertical         () const;
-      virtual bool           isFixed            () const;
-      virtual unsigned long  getId              () const;
-      virtual Flags          getDirection       () const;
-      virtual Net*           getNet             () const;
-      virtual const Layer*   getLayer           () const;
-      virtual TrackElement*  getNext            () const;
-      virtual TrackElement*  getPrevious        () const;
-      virtual DbU::Unit      getAxis            () const;
-      virtual Interval       getFreeInterval    () const;
-      virtual float          getPriority        () const;
-      virtual void           updatePriority     ( float );
-      virtual Record*        _getRecord         () const;
-      virtual string         _getString         () const;
-      virtual string         _getTypeName       () const;
+      static  TrackElement*  create                 ( Katana::Track* track , Segment* segment );
+    public:                                         
+      virtual AutoSegment*   base                   () const;
+      virtual Segment*       getSegment             () const;
+      virtual bool           isHorizontal           () const;
+      virtual bool           isVertical             () const;
+      virtual bool           isFixed                () const;
+      virtual bool           isPriorityLocked       () const;
+      virtual unsigned long  getId                  () const;
+      virtual Flags          getDirection           () const;
+      virtual Net*           getNet                 () const;
+      virtual const Layer*   getLayer               () const;
+      virtual TrackElement*  getNext                () const;
+      virtual TrackElement*  getPrevious            () const;
+      virtual DbU::Unit      getAxis                () const;
+      virtual Interval       getFreeInterval        () const;
+      virtual float          getPriority            () const;
+      virtual void           setPriorityLock        ( bool );
+      virtual void           forcePriority          ( float );
+      virtual void           computePriority        ();
+      virtual void           computeAlignedPriority ();
+      virtual Record*        _getRecord             () const;
+      virtual string         _getString             () const;
+      virtual string         _getTypeName           () const;
     protected:
     // Attributes.
       static Net*     _blockageNet;
diff --git a/katana/src/katana/TrackSegment.h b/katana/src/katana/TrackSegment.h
index 9b3ab788..c7135093 100644
--- a/katana/src/katana/TrackSegment.h
+++ b/katana/src/katana/TrackSegment.h
@@ -43,6 +43,11 @@ namespace Katana {
 // -------------------------------------------------------------------
 // Class  :  "TrackSegment".
 
+  enum TrackSegmentFlag { NoFlags        = 0
+                        , PriorityLocked = (1 << 0)
+                        };
+
+
   class TrackSegment : public TrackElement {
     public:
       class CompareById : public binary_function<const TrackSegment*,const TrackSegment*,bool> {
@@ -71,6 +76,8 @@ namespace Katana {
       virtual bool                  isReduced              () const;
       virtual bool                  isUTurn                () const;
       virtual bool                  isUserDefined          () const;
+      virtual bool                  isAnalog               () const;
+      virtual bool                  isPriorityLocked       () const;
     // Predicates.
       virtual bool                  hasSymmetric           () const;
       virtual bool                  canDogleg              ();
@@ -108,7 +115,10 @@ namespace Katana {
     // Mutators.
       virtual void                  setTrack               ( Track* );
       virtual void                  setSymmetric           ( TrackElement* );
-      virtual void                  updatePriority         ( float );
+      virtual void                  setPriorityLock        ( bool state );
+      virtual void                  forcePriority          ( float );
+      virtual void                  computePriority        ();
+      virtual void                  computeAlignedPriority ();
       virtual void                  updateFreedomDegree    ();
       virtual void                  setDoglegLevel         ( uint32_t );
       virtual void                  swapTrack              ( TrackElement* );
@@ -144,6 +154,7 @@ namespace Katana {
              DataNegociate* _data;
              float          _priority;
              unsigned int   _dogLegLevel:4;
+             uint32_t       _flags; 
 
     protected:
     // Constructors & Destructors.