Initial version of the P&S router. Buggy and crappy.

pcbnew/router/CMakeLists.txt

+include_directories(BEFORE ${INC_BEFORE})
+
+include_directories(
+		./
+		../
+    ../../include
+    ../../pcbnew
+    ../../polygon
+    ${INC_AFTER}
+    )
+
+set(PCBNEW_PNS_SRCS
+	direction.h
+	pns_via.h
+	pns_routing_settings.h
+	pns_shove.cpp
+	pns_line.cpp
+	pns_utils.h
+	pns_layerset.h
+	trace.h
+	pns_line.h
+	pns_walkaround.cpp
+	pns_node.h
+	pns_line_placer.cpp
+	pns_utils.cpp
+	pns_solid.h
+	pns_item.cpp
+	pns_via.cpp
+	pns_node.cpp
+	pns_solid.cpp
+	pns_line_placer.h
+	pns_optimizer.h
+	pns_walkaround.h
+	pns_shove.h
+	pns_router.h
+	pns_router.cpp
+	pns_index.h
+	pns_item.h
+	pns_optimizer.cpp
+	pns_joint.h
+	pns_segment.h
+	pns_itemset.h
+	pns_itemset.cpp
+	router_tool.cpp
+	router_tool.h
+	router_preview_item.cpp
+	router_preview_item.h
+	)
+
+add_library(pnsrouter STATIC ${PCBNEW_PNS_SRCS})

pcbnew/router/direction.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __DIRECTION_H
+#define __DIRECTION_H
+
+#include <geometry/seg.h>
+#include <geometry/shape_line_chain.h>
+
+/**
+ * Class DIRECTION_45.
+ * Represents route directions & corner angles in a 45-degree metric.
+ */
+
+class DIRECTION_45
+{
+	
+public:
+	
+	/**
+	 * Enum Directions
+	 * Represents available directions - there are 8 of them, as on a rectilinear map (north = up) +
+	 * an extra undefined direction, reserved for traces that don't respect 45-degree routing regime.
+	 */
+	enum Directions {
+		N = 0, 
+		NE = 1, 
+		E = 2, 
+		SE = 3, 
+		S = 4, 
+		SW = 5, 
+		W = 6, 
+		NW = 7, 
+		UNDEFINED = -1
+	};
+
+	/**
+	 * Enum AngleType
+	 * Represents kind of angle formed by vectors heading in two DIRECTION_45s. 
+	 */
+	enum AngleType {
+		ANG_OBTUSE = 0x1,
+		ANG_RIGHT = 0x2,
+		ANG_ACUTE = 0x4,
+		ANG_STRAIGHT = 0x8,
+		ANG_HALF_FULL = 0x10,
+		ANG_UNDEFINED = 0x20
+	};
+
+	DIRECTION_45(Directions aDir = UNDEFINED): m_dir(aDir) {};
+	
+	/**
+	 * Constructor
+	 * @param aVec vector, whose direction will be translated into a DIRECTION_45.
+	 */
+	DIRECTION_45(const VECTOR2I& aVec)
+	{
+		construct(aVec);
+	}
+
+	/**
+	 * Constructor
+	 * @param aSeg segment, whose direction will be translated into a DIRECTION_45.
+	 */
+	DIRECTION_45(const SEG& aSeg)
+	{
+		construct( aSeg.b - aSeg.a );
+	}
+
+	/**
+	 * Function Format()
+	 * Formats the direction in a human readable word.
+	 * @return name of the direction
+	 */
+	const std::string Format() const
+	{
+		switch(m_dir)
+		{
+			case N : return "north";
+			case NE : return "north-east";
+			case E : return "east";
+			case SE : return "south-east";
+			case S : return "south";
+			case SW : return "south-west";
+			case W : return "west";
+			case NW : return "north-west";
+			case UNDEFINED : return "undefined";
+			default: return "<Error>";
+		}
+	}
+	
+	/**
+	 * Function Opposite()
+	 * Returns a direction opposite (180 degree) to (this)
+	 * @return opposite direction
+	 */
+	DIRECTION_45 Opposite() const
+	{
+		if(m_dir == UNDEFINED)
+			return UNDEFINED;
+		const Directions OppositeMap[] = { S, SW, W, NW, N, NE, E, SE }	;
+		return OppositeMap[m_dir];
+	}
+
+	/**
+	 * Function Angle()
+	 * Returns the type of angle between directions (this) and aOther.
+	 * @param aOther direction to compare angle with
+	 */
+	AngleType Angle(const DIRECTION_45& aOther) const
+	{
+		if(m_dir == UNDEFINED || aOther.m_dir == UNDEFINED)
+			return ANG_UNDEFINED;
+
+		int d = std::abs(m_dir - aOther.m_dir);
+
+		if(d == 1 || d == 7)
+			return ANG_OBTUSE;
+		else if(d == 2 || d == 6)
+			return ANG_RIGHT;
+		else if(d == 3 || d == 5)
+			return ANG_ACUTE;
+		else if(d == 4)
+			return ANG_HALF_FULL;
+		else
+			return ANG_STRAIGHT;
+	}
+
+	/**
+	 * Function IsObtuse()
+	 * @return true, when (this) forms an obtuse angle with aOther
+	 */
+	bool IsObtuse(const DIRECTION_45& aOther) const
+	{
+		return Angle(aOther) == ANG_OBTUSE;
+	}
+
+	/**
+	 * Function IsDiagonal()
+	 * Returns true if the direction is diagonal (e.g. North-West, South-East, etc)
+	 * @return true, when diagonal.
+	 */
+	bool IsDiagonal() const
+	{
+		return (m_dir % 2) == 1;
+	}
+	
+	/**
+	 * Function BuildInitialTrace()
+	 *
+	 * Builds a 2-segment line chain between points aP0 and aP1 and following 45-degree routing
+	 * regime. If aStartDiagonal is true, the trace starts with a diagonal segment.
+	 * @param aP0 starting point
+	 * @param aP1 ending point
+	 * @param aStartDiagonal whether the first segment has to be diagonal
+	 * @return the trace
+	 */
+	const SHAPE_LINE_CHAIN BuildInitialTrace(const VECTOR2I& aP0, const VECTOR2I &aP1, bool aStartDiagonal = false) const
+	{
+		int w = abs(aP1.x - aP0.x);
+		int h = abs(aP1.y - aP0.y);	
+		int sw = sign(aP1.x - aP0.x);
+		int sh = sign(aP1.y - aP0.y);		
+
+		VECTOR2I mp0, mp1;
+		
+		// we are more horizontal than vertical?
+		if(w > h)
+		{
+			mp0 = VECTOR2I((w - h) * sw, 0); // direction: E
+			mp1 = VECTOR2I(h * sw, h * sh);	 // direction: NE
+		} else {
+			mp0 = VECTOR2I(0, sh * (h - w)); // direction: N
+			mp1 = VECTOR2I(sw * w, sh * w);  // direction: NE
+		}
+
+		bool start_diagonal;
+
+		if(m_dir == UNDEFINED)
+			start_diagonal = aStartDiagonal;
+		else
+			start_diagonal = IsDiagonal();
+
+		SHAPE_LINE_CHAIN pl;
+
+		pl.Append(aP0);
+		if (start_diagonal)
+			pl.Append(aP0 + mp1);
+		else
+			pl.Append(aP0 + mp0);
+		
+		pl.Append(aP1);
+		pl.Simplify();
+		return pl;
+	};
+
+	bool operator==(const DIRECTION_45& aOther) const
+	{
+		return aOther.m_dir == m_dir;
+	}
+
+	bool operator!=(const DIRECTION_45& aOther) const
+	{
+		return aOther.m_dir != m_dir;
+	}
+
+	const DIRECTION_45 Right() const
+	{
+		DIRECTION_45 r;
+		r.m_dir = (Directions) (m_dir + 1);
+		if(r.m_dir == NW)
+			r.m_dir = N;
+		return r;
+	}
+
+private:
+
+	template <typename T> int sign(T val) const {
+    	return (T(0) < val) - (val < T(0));
+	}
+
+	/** 
+	 * Function construct()
+	 * Calculates the direction from a vector. If the vector's angle is not a multiple of 45
+	 * degrees, the direction is rounded to the nearest octant.
+	 * @param aVec our vector
+	 */
+	void construct(const VECTOR2I& aVec)
+	{
+		m_dir = UNDEFINED;
+		if(aVec.x == 0 && aVec.y == 0)
+			return;
+
+		double mag = 360.0 - (180.0 / M_PI * atan2 ((double) aVec.y, (double) aVec.x )) + 90.0;
+		if (mag >= 360.0)
+			mag -= 360.0;
+		if(mag < 0.0)
+			mag += 360.0;
+ 
+ 		m_dir = (Directions) ((mag + 22.5) / 45.0);
+
+ 		if(m_dir >= 8)
+ 			m_dir = (Directions) (m_dir - 8);
+ 		if(m_dir < 0)
+ 			m_dir = (Directions) (m_dir + 8);
+
+ 		return ;
+		if(aVec.y < 0)
+		{
+			if(aVec.x > 0)
+				m_dir = NE;
+			else if(aVec.x < 0)
+				m_dir = NW;
+			else
+				m_dir = N;
+		}
+		else if(aVec.y == 0)
+		{
+			if(aVec.x > 0)
+				m_dir = E;
+			else
+				m_dir = W;
+		}
+		else  // aVec.y>0
+		{
+			if(aVec.x > 0)
+				m_dir = SE;
+			else if(aVec.x < 0)
+				m_dir = SW;
+			else
+				m_dir = S;
+		}
+	}
+
+	Directions m_dir; ///> our actual direction
+};		
+
+#endif // __DIRECTION_H

pcbnew/router/pns_index.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_INDEX_H
+#define __PNS_INDEX_H
+
+#include <boost/foreach.hpp>
+#include <boost/range/adaptor/map.hpp>
+
+#include <list>
+#include <geometry/shape_index.h>
+
+#include "pns_item.h"
+
+/**
+ * Class PNS_INDEX
+ *
+ * Custom spatial index, holding our board items and allowing for very fast searches. Items
+ * are assigned to separate R-Tree subundices depending on their type and spanned layers, reducing
+ * overlap and improving search time.
+ **/
+
+class PNS_INDEX {
+
+public:
+	
+	typedef std::list<PNS_ITEM *> NetItemsList;
+	typedef SHAPE_INDEX<PNS_ITEM *> ItemShapeIndex;
+	typedef boost::unordered_set<PNS_ITEM *> ItemSet;
+
+	PNS_INDEX();
+	~PNS_INDEX();
+
+	void Add( PNS_ITEM *aItem );
+	void Remove ( PNS_ITEM *aItem );
+	void Replace ( PNS_ITEM *aOldItem, PNS_ITEM *aNewItem );
+
+	template<class Visitor>
+		int Query( const PNS_ITEM *aItem, int aMinDistance, Visitor &v);
+	template<class Visitor>
+		int Query( const SHAPE *aShape, int aMinDistance, Visitor &v);
+
+	void Clear();
+
+	NetItemsList* GetItemsForNet ( int aNet ) ;
+
+	ItemSet::iterator begin() { return m_allItems.begin(); }
+	ItemSet::iterator end() { return m_allItems.end(); }
+
+	bool Contains ( PNS_ITEM *aItem ) const {
+		return m_allItems.find(aItem) != m_allItems.end();
+	}
+
+	int Size() const { return m_allItems.size(); }
+
+private:
+	
+
+	static const int MaxSubIndices = 64;
+	static const int SI_Multilayer = 2;
+	static const int SI_SegDiagonal = 0;
+	static const int SI_SegStraight = 1;
+	static const int SI_Traces = 3;
+	static const int SI_PadsTop = 0;
+	static const int SI_PadsBottom = 1;
+
+	template<class Visitor>
+		int querySingle( int index, const SHAPE *aShape, int aMinDistance, Visitor &v);
+
+	ItemShapeIndex *getSubindex( const PNS_ITEM *aItem );
+
+	ItemShapeIndex *m_subIndices[ MaxSubIndices ];
+	std::map<int, NetItemsList> m_netMap;
+	ItemSet m_allItems;
+};
+
+PNS_INDEX::PNS_INDEX()
+{
+	memset(m_subIndices, 0, sizeof(m_subIndices));
+}
+
+PNS_INDEX::ItemShapeIndex *PNS_INDEX::getSubindex(const PNS_ITEM *aItem ) 
+{
+	int idx_n = -1;
+
+	const PNS_LAYERSET l = aItem->GetLayers();
+	
+	switch(aItem->GetKind())
+	{
+		case PNS_ITEM::VIA: 
+			idx_n = SI_Multilayer;
+			break;
+		case PNS_ITEM::SOLID:
+		{
+			if( l.IsMultilayer() )
+				idx_n = SI_Multilayer;
+			else if (l.Start() == 0) // fixme: use kicad layer codes
+				idx_n = SI_PadsTop;
+			else if (l.Start() == 15) 
+				idx_n = SI_PadsBottom;
+			break;
+		}
+		case PNS_ITEM::SEGMENT:
+		case PNS_ITEM::LINE:
+			idx_n = SI_Traces + 2 * l.Start() + SI_SegStraight;
+			break;
+		default:
+			break;
+	}
+	assert(idx_n >= 0 && idx_n < MaxSubIndices);
+
+	if(!m_subIndices[idx_n])
+		m_subIndices[idx_n] = new ItemShapeIndex;
+
+	return m_subIndices[idx_n];
+}
+
+void PNS_INDEX::Add( PNS_ITEM *aItem )
+{
+	ItemShapeIndex *idx = getSubindex(aItem);
+	
+
+	idx->Add(aItem);
+	m_allItems.insert(aItem);
+	int net = aItem->GetNet();
+	if(net >= 0)
+	{
+		m_netMap[net].push_back(aItem);
+	}
+}
+
+void PNS_INDEX::Remove( PNS_ITEM *aItem )
+{
+	ItemShapeIndex *idx = getSubindex(aItem);
+	idx->Remove(aItem);
+	m_allItems.erase (aItem);
+
+	int net = aItem->GetNet();
+	
+	if(net >= 0 && m_netMap.find(net) != m_netMap.end())
+		m_netMap[net].remove(aItem);
+}
+
+void PNS_INDEX::Replace( PNS_ITEM *aOldItem, PNS_ITEM *aNewItem )
+{
+	Remove(aOldItem);
+	Add(aNewItem);
+}
+
+template<class Visitor>
+	int PNS_INDEX::querySingle( int index, const SHAPE *aShape, int aMinDistance, Visitor &v)
+	{
+		if(!m_subIndices[index])
+			return 0;
+		return m_subIndices[index] -> Query(aShape, aMinDistance, v, false);
+	}
+
+template<class Visitor>
+	int PNS_INDEX::Query( const PNS_ITEM *aItem, int aMinDistance, Visitor &v)
+	{
+		const SHAPE *shape = aItem->GetShape();
+		int total = 0;
+		
+			
+		total += querySingle(SI_Multilayer, shape, aMinDistance, v);
+
+		const PNS_LAYERSET layers = aItem->GetLayers();
+		
+		if(layers.IsMultilayer())
+		{
+			total += querySingle(SI_PadsTop, shape, aMinDistance, v);
+			total += querySingle(SI_PadsBottom, shape, aMinDistance, v);
+
+		
+			for(int i = layers.Start(); i <= layers.End(); ++i )
+				total += querySingle( SI_Traces + 2 * i + SI_SegStraight, shape, aMinDistance, v);
+
+		} else {
+			int l = layers.Start();
+
+			if(l == 0)
+				total += querySingle(SI_PadsTop, shape, aMinDistance, v);
+			else if(l == 15)
+				total += querySingle(SI_PadsBottom, shape, aMinDistance, v);
+			total += querySingle (  SI_Traces + 2 * l + SI_SegStraight, shape, aMinDistance, v);
+		}
+
+		return total;
+	}
+
+template<class Visitor>
+	int PNS_INDEX::Query( const SHAPE *aShape, int aMinDistance, Visitor &v)
+	{
+		int total = 0;
+		for(int i = 0; i < MaxSubIndices; i++)
+			total += querySingle(i, aShape, aMinDistance, v);
+		return total;
+	}
+
+		
+void PNS_INDEX::Clear()
+{
+	for(int i = 0; i < MaxSubIndices; ++i)
+	{
+		ItemShapeIndex *idx = m_subIndices[i];
+		if(idx)
+			delete idx;
+		m_subIndices[i] = NULL;
+	}
+}
+
+PNS_INDEX::~PNS_INDEX()
+{
+	Clear();
+}
+
+PNS_INDEX::NetItemsList* PNS_INDEX::GetItemsForNet ( int aNet ) 
+{
+	if(m_netMap.find(aNet) == m_netMap.end())
+		return NULL;
+	return &m_netMap[aNet];
+}
+
+#endif

pcbnew/router/pns_item.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include "pns_item.h"
+#include "pns_line.h"
+
+bool PNS_ITEM::collideSimple ( const PNS_ITEM *aOther, int aClearance, bool aNeedMTV, VECTOR2I& aMTV ) const
+{
+	// same nets? no collision!
+	if( m_net == aOther->m_net )
+		return false;	
+
+	// check if we are not on completely different layers first
+	if (!m_layers.Overlaps (aOther->m_layers))
+		return false;
+
+	return GetShape()->Collide ( aOther->GetShape(), aClearance );
+
+	// fixme: MTV
+}
+
+bool PNS_ITEM::Collide( const PNS_ITEM *aOther, int aClearance, bool aNeedMTV, VECTOR2I& aMTV ) const
+{
+	if( collideSimple( aOther, aClearance, aNeedMTV, aMTV ) )
+		return true;
+
+	// special case for "head" line with a via attached at the end. 
+	if( aOther->m_kind == LINE ) 
+	{
+		const PNS_LINE *line = static_cast<const PNS_LINE *> (aOther);
+		if(line -> EndsWithVia())
+			return collideSimple( &line->GetVia(), aClearance - line->GetWidth() / 2, aNeedMTV, aMTV );
+	}
+
+	return false;
+}
+
+const std::string PNS_ITEM::GetKindStr() const
+{
+	switch(m_kind)
+	{
+		case LINE: return "line";
+		case SEGMENT: return "segment";
+		case VIA: return "via";
+		case JOINT: return "joint";
+		case SOLID: return "solid";
+		default: return "unknown";
+	}
+}
+
+PNS_ITEM::~PNS_ITEM()
+{
+		
+}
+	
\ No newline at end of file

pcbnew/router/pns_item.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_ITEM_H
+#define __PNS_ITEM_H
+
+#include <math/vector2d.h>
+
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+
+#include "pns_layerset.h"
+
+class BOARD_ITEM;
+class PNS_NODE;
+
+/**
+ * Class PNS_ITEM
+ *
+ * Base class for PNS router board items. Implements the shared properties of all PCB items -
+ * net, spanned layers, geometric shape & refererence to owning model.
+ */
+ 
+class PNS_ITEM 
+{
+public:
+
+	static const int UnusedNet = INT_MAX;
+
+	///> Supported item types
+	enum PnsKind {
+		SOLID 		= 1,
+		LINE 		= 2,
+		JOINT 		= 4,
+		SEGMENT 	= 8,
+		VIA 		= 16,
+		ANY 		= 0xff
+	};
+
+	PNS_ITEM(PnsKind aKind)
+	{	
+		m_net = UnusedNet;
+		m_movable = true;
+		m_kind = aKind;
+		m_parent = NULL;
+		m_world = NULL;
+		m_owner = NULL;
+	}
+
+	PNS_ITEM( const PNS_ITEM& aOther )
+	{
+		m_layers = aOther.m_layers;
+		m_net = aOther.m_net;
+		m_movable = aOther.m_movable;
+		m_kind = aOther.m_kind;
+		m_world = aOther.m_world;
+		m_parent = aOther.m_parent;
+		m_owner = NULL;
+	}
+
+	virtual ~PNS_ITEM();
+	
+	virtual PNS_ITEM *Clone() const = 0;
+
+	///> Returns a convex polygon "hull" of a the item, that is used as the walkaround
+	///  path. 
+	///  aClearance defines how far from the body of the item the hull should be,
+	///  aWalkaroundThickness is the width of the line that walks around this hull.
+	virtual const SHAPE_LINE_CHAIN Hull(int aClearance = 0, int aWalkaroundThickness = 0) const 
+	{
+		return SHAPE_LINE_CHAIN();
+	};
+
+
+	
+	PnsKind GetKind() const 		{  return m_kind; }
+	bool OfKind( int aKind ) const 	{ return (aKind & m_kind) != 0; }
+	
+	const std::string GetKindStr() const;
+	
+	///> Gets/Sets the corresponding parent object in the host application's model (pcbnew) 
+	void SetParent(BOARD_ITEM *aParent) { m_parent = aParent; }
+	BOARD_ITEM *GetParent() const 	{  return m_parent;  }
+
+	///> Net accessors
+	int GetNet() const 				{ return m_net; }
+	void SetNet(int aNet) 			{ m_net = aNet; }
+
+	///> Layers accessors
+	const PNS_LAYERSET& GetLayers() const 				{	return m_layers;	}
+	void SetLayers ( const PNS_LAYERSET& aLayers ) 		{ m_layers = aLayers; }
+	void SetLayer ( int aLayer ) 						{ m_layers = PNS_LAYERSET (aLayer, aLayer); }
+
+	///> Ownership management. An item can belong to a single PNS_NODE or stay unowned.
+	void SetOwner (PNS_NODE *aOwner) 			{ m_owner = aOwner; }
+	bool BelongsTo (PNS_NODE *aNode) const 		{ return m_owner == aNode; }
+	PNS_NODE *GetOwner() const 					{ return m_owner; }
+
+	///> Sets the world that is used for collision resolution.
+	void SetWorld (PNS_NODE *aWorld) 			{ m_world = aWorld; }
+	PNS_NODE *GetWorld() const 					{ return m_world; }
+
+
+	///> Collision function. Checks if the item aOther is closer to us than
+	/// aClearance and returns true if so. It can also calculate a minimum translation vector that resolves the
+	/// collision if needed.
+	virtual bool Collide( const PNS_ITEM *aOther, int aClearance, bool aNeedMTV, VECTOR2I& aMTV ) const;
+
+	///> A shortcut without MTV calculation
+	bool Collide( const PNS_ITEM *aOther, int aClearance ) const
+	{
+		VECTOR2I dummy;
+		return Collide(aOther, aClearance, false, dummy);
+	}
+	
+	///> Returns the geometric shape of the item
+	virtual	const SHAPE* GetShape() const { 
+		return NULL;
+	}
+
+private:
+	bool collideSimple ( const PNS_ITEM *aOther, int aClearance, bool aNeedMTV, VECTOR2I& aMTV ) const;
+
+protected:
+
+	PnsKind m_kind;
+	
+	BOARD_ITEM *m_parent;
+	PNS_NODE *m_world;
+	PNS_NODE *m_owner;
+	PNS_LAYERSET m_layers;
+
+	bool m_movable;
+	int m_net;
+};
+
+#endif // __PNS_ITEM_H
+

pcbnew/router/pns_itemset.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <boost/foreach.hpp>
+
+#include "pns_itemset.h"
+
+
+PNS_ITEMSET::PNS_ITEMSET()
+{
+
+}
+
+PNS_ITEMSET::~PNS_ITEMSET()
+{
+
+}
+
+PNS_ITEMSET& PNS_ITEMSET::FilterLayers ( int aStart, int aEnd )
+{
+	ItemVector newItems;
+	PNS_LAYERSET l;
+	if(aEnd < 0)
+		l = PNS_LAYERSET(aStart);
+	else
+		l = PNS_LAYERSET(aStart, aEnd);
+
+	BOOST_FOREACH( PNS_ITEM *item, m_items )
+		if(item->GetLayers(). Overlaps ( l ))
+			newItems.push_back(item);
+	m_items = newItems;
+	return *this;
+}
+
+PNS_ITEMSET& PNS_ITEMSET::FilterKinds ( int aKindMask )
+{
+	ItemVector newItems;
+	
+	BOOST_FOREACH( PNS_ITEM *item, m_items )
+		if(item->GetKind() & aKindMask )
+			newItems.push_back(item);
+	m_items = newItems;
+	return *this;
+}
+
+PNS_ITEMSET& PNS_ITEMSET::FilterNet ( int aNet )
+{
+	ItemVector newItems;
+	
+	BOOST_FOREACH( PNS_ITEM *item, m_items )
+		if(item->GetNet() == aNet)
+			newItems.push_back(item);
+	m_items = newItems;
+	return *this;
+}
+

pcbnew/router/pns_itemset.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_ITEMSET_H
+#define __PNS_ITEMSET_H
+
+#include <vector>
+
+#include "pns_item.h"
+
+/**
+ * Class PNS_ITEMSET
+ *
+ * Holds a list of board items, that can be filtered against net, kinds, layers, etc.
+ **/
+
+class PNS_ITEMSET
+{
+public:
+
+	typedef std::vector<PNS_ITEM *> ItemVector;
+
+	PNS_ITEMSET();
+	~PNS_ITEMSET();
+
+	ItemVector& Items() { return m_items; }
+
+	PNS_ITEMSET& FilterLayers ( int aStart, int aEnd = -1 );
+	PNS_ITEMSET& FilterKinds ( int aKindMask );
+	PNS_ITEMSET& FilterNet ( int aNet );
+	
+	int Size() { return m_items.size(); }	
+
+	void Add(PNS_ITEM *item)
+	{
+		m_items.push_back(item);
+	}
+
+	PNS_ITEM *Get( int index ) const { return m_items[index]; }
+
+private:
+	ItemVector m_items;
+};
+
+#endif

pcbnew/router/pns_joint.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_JOINT_H
+#define __PNS_JOINT_H
+
+#include <vector>
+#include <boost/functional/hash.hpp>
+
+#include <math/vector2d.h>
+
+#include "pns_item.h"
+#include "pns_segment.h"
+
+/**
+ * Class PNS_JOINT
+ * 
+ * Represents a 2D point on a given set of layers and belonging to a certain net,
+ * that links together a number of board items.
+ * A hash table of joints is used by the router to follow connectivity between the items.
+ **/
+
+class PNS_JOINT : public PNS_ITEM
+{
+public:
+	typedef std::vector<PNS_ITEM *> LinkedItems;
+
+	///> joints are hashed by their position, layers and net. Linked items are, obviously, not hashed
+	struct HashTag {
+		VECTOR2I pos;
+		int net;
+	};
+	
+	PNS_JOINT():
+		PNS_ITEM(JOINT) {}
+
+	PNS_JOINT(const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet = -1):
+		PNS_ITEM(JOINT)
+	{
+		m_tag.pos = aPos;
+		m_tag.net = aNet;
+		m_layers = aLayers;
+	}
+
+	PNS_JOINT(const PNS_JOINT& b): 
+		PNS_ITEM(JOINT)
+	{
+		m_layers = b.m_layers;
+		m_tag.pos = b.m_tag.pos;
+		m_tag.net = b.m_tag.net;
+		m_linkedItems = b.m_linkedItems;
+		m_layers = b.m_layers;
+	}
+
+	PNS_ITEM *Clone() const
+	{
+		assert(false);
+		return NULL;
+	}
+
+	///> returns true if the joint is a trivial line corner, connecting two segments of the same net, on the same layer.
+	bool IsLineCorner() const
+	{
+		if(m_linkedItems.size() != 2)
+			return false;
+
+		if( m_linkedItems[0]->GetKind() != SEGMENT || m_linkedItems[1]->GetKind() != SEGMENT )
+			return false;
+
+		PNS_SEGMENT *seg1 = static_cast<PNS_SEGMENT *> (m_linkedItems[0]);
+		PNS_SEGMENT *seg2 = static_cast<PNS_SEGMENT *> (m_linkedItems[1]);
+
+		// joints between segments of different widths are not trivial.
+		return (seg1->GetWidth() == seg2->GetWidth());
+	}
+
+	///> Links the joint to a given board item (when it's added to the PNS_NODE)
+	void Link ( PNS_ITEM *aItem )
+	{
+		LinkedItems::iterator f = std::find(m_linkedItems.begin(), m_linkedItems.end(), aItem);
+		if(f != m_linkedItems.end())
+			return;
+		m_linkedItems.push_back(aItem);
+	}
+
+	///> Unlinks a given board item from the joint (upon its removal from a PNS_NODE)
+	///> Returns true if the joint became dangling after unlinking.
+	bool Unlink ( PNS_ITEM *aItem )
+	{
+		LinkedItems::iterator f = std::find(m_linkedItems.begin(), m_linkedItems.end(), aItem);
+		if(f != m_linkedItems.end())
+			m_linkedItems.erase(f);
+		return (m_linkedItems.size() == 0);
+	}
+
+	///> For trivial joints, returns the segment adjacent to (aCurrent). For non-trival ones, returns 
+	///> NULL, indicating the end of line.
+	PNS_SEGMENT* NextSegment( PNS_SEGMENT* aCurrent) const
+	{
+		if(!IsLineCorner())
+			return NULL;
+		
+		return static_cast<PNS_SEGMENT *> (m_linkedItems [ m_linkedItems[0] == aCurrent ? 1 : 0 ] );
+	}
+
+	/// trivial accessors	
+	const HashTag& GetTag() const 	{ return m_tag; }
+	const VECTOR2I& GetPos() const 	{ return m_tag.pos; }
+	int GetNet() const 				{ return m_tag.net; }
+	LinkedItems & GetLinkList() 	{ return m_linkedItems; };
+
+	///> Returns the number of linked items of types listed in aMask.
+	int LinkCount( int aMask = -1 ) const
+	{
+		int n = 0;
+		for(LinkedItems::const_iterator i = m_linkedItems.begin(); i!= m_linkedItems.end(); ++i)
+			if( (*i)->GetKind() & aMask )
+				n++;
+		return n;
+	}
+
+	void Dump() const;
+	
+	bool operator==(const PNS_JOINT& rhs)  const
+	{
+		return m_tag.pos == rhs.m_tag.pos && m_tag.net == rhs.m_tag.net;
+	}
+
+	void Merge( const PNS_JOINT& aJoint )
+	{
+		if(!Overlaps(aJoint))
+			return;
+		
+		m_layers.Merge (aJoint.m_layers);
+
+		// fixme: duplicate links (?)
+		for(LinkedItems::const_iterator i =aJoint.m_linkedItems.begin(); i!=aJoint.m_linkedItems.end();++i)
+			m_linkedItems.push_back(*i);
+	}
+
+	bool Overlaps(const PNS_JOINT& rhs) const
+	{
+		return m_tag.pos == rhs.m_tag.pos && m_tag.net == rhs.m_tag.net && m_layers.Overlaps(rhs.m_layers);
+	}
+
+private:
+
+	///> hash tag for unordered_multimap
+	HashTag m_tag;
+
+	///> list of items linked to this joint
+	LinkedItems m_linkedItems;
+};
+
+
+// hash function & comparison operator for boost::unordered_map<>
+inline bool operator==(PNS_JOINT::HashTag const& p1, PNS_JOINT::HashTag const& p2)
+{
+    return p1.pos == p2.pos && p1.net == p2.net;
+}
+
+inline std::size_t hash_value(PNS_JOINT::HashTag const& p) 
+{
+    std::size_t seed = 0;
+    boost::hash_combine(seed, p.pos.x);
+    boost::hash_combine(seed, p.pos.y);
+    boost::hash_combine(seed, p.net);
+    return seed;
+}
+
+#endif // __PNS_JOINT_H

pcbnew/router/pns_layerset.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_LAYERSET_H
+#define __PNS_LAYERSET_H
+
+#include <algorithm>
+
+/**
+ * Class PNS_LAYERSET
+ *
+ * Represents a contiguous set of PCB layers. 
+ */
+
+class PNS_LAYERSET
+{
+	public:
+
+		PNS_LAYERSET():
+			m_start(-1),
+			m_end(-1)
+			{};
+
+		PNS_LAYERSET (int aStart, int aEnd)
+		{
+			if(aStart > aEnd)
+				std::swap(aStart, aEnd);
+			m_start = aStart;
+			m_end = aEnd;
+		}
+
+		PNS_LAYERSET (int aLayer)
+		{
+			m_start = m_end = aLayer;
+		}
+
+		PNS_LAYERSET(const PNS_LAYERSET &b) :
+			m_start(b.m_start),
+			m_end (b.m_end)
+			{}
+
+		~PNS_LAYERSET () {};
+
+		const PNS_LAYERSET& operator= ( const PNS_LAYERSET& b)
+		{
+			m_start = b.m_start;
+			m_end = b.m_end;
+			return *this;
+		}
+
+		bool Overlaps ( const PNS_LAYERSET& aOther ) const
+		{
+			return m_end >= aOther.m_start && m_start <= aOther.m_end;
+		}
+
+		bool Overlaps ( const int aLayer ) const
+		{
+			return aLayer >= m_start && aLayer <= m_end;
+		}
+
+		bool IsMultilayer ( ) const
+		{
+			return m_start != m_end;
+		}
+
+		int Start() const {
+			return m_start;
+		}
+
+		int End() const {
+			return m_end;
+		}
+
+		void Merge ( const PNS_LAYERSET& aOther )
+		{
+			if(m_start < 0 || m_end < 0)
+			{
+				m_start = aOther.m_start;
+				m_end = aOther.m_end;
+				return;
+			} 	
+
+			if(aOther.m_start < m_start)
+				m_start = aOther.m_start;
+			if(aOther.m_end > m_end)
+				m_end = aOther.m_end;
+		}
+
+		///> Shortcut for comparisons/overlap tests
+		static PNS_LAYERSET All()
+		{
+			return PNS_LAYERSET(0, 256);
+		}
+
+	private:
+
+		int m_start;
+		int m_end;
+};
+
+#endif // __PNS_LAYERSET_H

pcbnew/router/pns_line.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <boost/foreach.hpp>
+#include <boost/optional.hpp>
+
+#include <math/vector2d.h>
+
+
+#include "pns_line.h"
+#include "pns_node.h"
+#include "pns_via.h"
+#include "pns_utils.h"
+#include "pns_router.h"
+
+using namespace std;
+using boost::optional;
+
+PNS_LINE *PNS_LINE::Clone() const
+{
+	PNS_LINE *l = new PNS_LINE();
+
+	l->m_line = m_line;
+	l->m_width = m_width;
+	l->m_layers = m_layers;
+	l->m_net = m_net;
+	l->m_movable = m_movable;
+	l->m_segmentRefs = NULL;
+	l->m_hasVia = m_hasVia;
+	l->m_via = m_via;
+		
+	return l;
+}
+
+PNS_LINE *PNS_LINE::CloneProperties() const
+{
+	PNS_LINE *l = new PNS_LINE();
+
+	l->m_width = m_width;
+	l->m_layers = m_layers;
+	l->m_net = m_net;
+	l->m_movable = m_movable;
+
+	return l;
+}	
+	
+PNS_SEGMENT *PNS_SEGMENT::Clone() const
+{
+	PNS_SEGMENT *s = new PNS_SEGMENT;
+	s->m_width = m_width;
+	s->m_net = m_net;
+	s->m_shape = m_shape;
+	s->m_layers = m_layers;
+
+	return s;	//assert(false);
+}
+
+#if 1
+bool PNS_LINE::MergeObtuseSegments( ) 
+{
+	int step = m_line.PointCount() - 3;
+	int iter = 0;
+	
+	int segs_pre = m_line.SegmentCount();
+
+	if(step < 0)
+		return false;
+
+	SHAPE_LINE_CHAIN current_path (m_line);
+
+	while(1)
+	{
+		iter++;
+		int n_segs = current_path.SegmentCount();
+		int max_step = n_segs - 2;
+		if(step > max_step)
+			step = max_step;
+
+		if(step < 2)
+		{
+			m_line = current_path;
+			return current_path.SegmentCount() < segs_pre;
+		}
+
+		bool found_anything = false;
+		int n = 0;
+
+		while (n < n_segs - step)
+		{
+			const SEG s1 = current_path.CSegment(n);
+			const SEG s2 = current_path.CSegment(n + step);
+			SEG s1opt, s2opt;
+
+			if (DIRECTION_45(s1).IsObtuse(DIRECTION_45(s2)))
+			{
+				VECTOR2I ip = *s1.IntersectLines(s2);
+
+				if(s1.Distance(ip) <= 1 || s2.Distance(ip) <= 1)
+				{
+					s1opt = SEG(s1.a, ip);
+					s2opt = SEG(ip, s2.b);
+				} else {
+					s1opt = SEG(s1.a, ip);
+					s2opt = SEG(ip, s2.b);
+				}
+						
+						
+				if (DIRECTION_45(s1opt).IsObtuse(DIRECTION_45(s2opt)))
+				{
+					SHAPE_LINE_CHAIN opt_path;
+					opt_path.Append(s1opt.a);
+					opt_path.Append(s1opt.b);
+					opt_path.Append(s2opt.b);
+
+					PNS_LINE opt_track (*this, opt_path);
+
+					if(!m_world->CheckColliding(&opt_track, PNS_ITEM::ANY))
+					{
+						current_path.Replace(s1.Index() + 1, s2.Index(), ip);
+						n_segs = current_path.SegmentCount();
+						found_anything = true;
+						break;
+					}
+				}
+			}
+			n++;
+		}
+
+		if(!found_anything)
+		{
+			if( step <= 2 )
+			{
+				m_line = current_path;
+				return m_line.SegmentCount() < segs_pre;
+			}
+			step --;
+		}
+	}
+	return  m_line.SegmentCount() < segs_pre;
+}
+
+bool PNS_LINE::MergeSegments( ) 
+{
+	int step = m_line.PointCount() - 3;
+	int iter = 0;
+	
+	int segs_pre = m_line.SegmentCount();
+
+	if(step < 0)
+		return false;
+
+	SHAPE_LINE_CHAIN current_path (m_line);
+
+	while(1)
+	{
+		iter++;
+		int n_segs = current_path.SegmentCount();
+		int max_step = n_segs - 2;
+		if(step > max_step)
+			step = max_step;
+
+		if(step < 2)
+		{
+			m_line = current_path;
+			return current_path.SegmentCount() < segs_pre;
+		}
+
+		bool found_anything = false;
+		int n = 0;
+
+		while (n < n_segs - step)
+		{
+			const SEG s1 = current_path.CSegment(n);
+			const SEG s2 = current_path.CSegment(n + step);
+			SEG s1opt, s2opt;
+
+			if(n > 0)
+			{
+				SHAPE_LINE_CHAIN path_straight = DIRECTION_45().BuildInitialTrace(s1.a, s2.a, false);
+				SHAPE_LINE_CHAIN path_diagonal = DIRECTION_45().BuildInitialTrace(s1.a, s2.a, true);
+
+				
+			
+			}
+
+			if (DIRECTION_45(s1) == DIRECTION_45(s2))
+			{
+				if(s1.Collinear(s2))
+				{
+					//printf("Colinear: np %d step %d n1 %d n2 %d\n", n_segs, step, n, n+step);
+
+					SHAPE_LINE_CHAIN opt_path;
+					opt_path.Append(s1.a);
+					opt_path.Append(s2.b);
+					
+					PNS_LINE tmp (*this, opt_path);
+					
+					if(!m_world->CheckColliding(&tmp, PNS_ITEM::ANY))
+					{
+						current_path.Remove(s1.Index() + 1, s2.Index());
+						n_segs = current_path.SegmentCount();
+						found_anything = true;
+						break;
+					}
+						
+				}
+
+					
+			}
+			else if (DIRECTION_45(s1).IsObtuse(DIRECTION_45(s2)))
+			{
+				VECTOR2I ip = *s1.IntersectLines(s2);
+
+				if(s1.Distance(ip) <= 1 || s2.Distance(ip) <= 1)
+				{
+					s1opt = SEG(s1.a, ip);
+					s2opt = SEG(ip, s2.b);
+				} else {
+					s1opt = SEG(s1.a, ip);
+					s2opt = SEG(ip, s2.b);
+				}
+						
+						
+				if (DIRECTION_45(s1opt).IsObtuse(DIRECTION_45(s2opt)))
+				{
+					SHAPE_LINE_CHAIN opt_path;
+					opt_path.Append(s1opt.a);
+					opt_path.Append(s1opt.b);
+					opt_path.Append(s2opt.b);
+
+					PNS_LINE opt_track (*this, opt_path);
+					
+					if(!m_world->CheckColliding(&opt_track, PNS_ITEM::ANY))
+					{
+						current_path.Replace(s1.Index() + 1, s2.Index(), ip);
+						n_segs = current_path.SegmentCount();
+						found_anything = true;
+						break;
+					}
+				}
+				
+			}
+			n++;
+		}
+
+		if(!found_anything)
+		{
+			if( step <= 2 )
+			{
+				m_line = current_path;
+				return m_line.SegmentCount() < segs_pre;
+			}
+			step --;
+		}
+	}
+	return  m_line.SegmentCount() < segs_pre;
+}
+
+
+#endif
+
+int PNS_LINE::CountCorners(int aAngles)
+{
+	int count = 0;
+	for(int i = 0; i < m_line.SegmentCount() - 1; i ++)
+	{
+		const SEG seg1 = m_line.CSegment(i);
+		const SEG seg2 = m_line.CSegment(i + 1);
+
+		const DIRECTION_45 dir1(seg1);
+		const DIRECTION_45 dir2(seg2);
+
+		DIRECTION_45::AngleType a = dir1.Angle(dir2);
+		if(a & aAngles)
+			count++;
+	}
+	return count;
+}
+
+//#define DUMP_TEST_CASES 
+
+// fixme: damn f*****g inefficient and incredibly crappily written
+void PNS_LINE::NewWalkaround( const SHAPE_LINE_CHAIN& aObstacle, 
+									SHAPE_LINE_CHAIN& aPrePath,
+					 			 	SHAPE_LINE_CHAIN& aWalkaroundPath,
+					 			 	SHAPE_LINE_CHAIN& aPostPath,
+					 			 	bool aCw ) const
+{
+
+	typedef SHAPE_LINE_CHAIN::Intersection Intersection;
+
+	SHAPE_LINE_CHAIN l_orig(m_line);
+	SHAPE_LINE_CHAIN l_hull;
+	vector<bool> outside, on_edge, inside;
+	SHAPE_LINE_CHAIN path;
+	
+	vector<Intersection> isects;
+
+	// don't calculate walkaround for empty lines
+	if(m_line.PointCount() < 2)
+		return;
+
+#ifdef DUMP_TEST_CASES
+	printf("%s\n", m_line.Format().c_str());
+	printf("%s\n", aObstacle.Format().c_str());
+#endif
+
+	aObstacle.Intersect(m_line, isects);
+	//printf("NewWalk intersectiosn :%d\n" ,isects.size());
+	if( !aCw )
+		l_hull = aObstacle.Reverse();
+	else
+		l_hull = aObstacle;
+
+	BOOST_FOREACH( Intersection isect, isects )
+	{
+		l_orig.Split(isect.p);
+		l_hull.Split(isect.p);
+	}
+
+
+#ifdef DUMP_TEST_CASES
+	printf("%s\n", m_line.Format().c_str());
+	printf("%s\n", aObstacle.Format().c_str());
+	printf("%s\n", l_orig.Format().c_str());
+	printf("%s\n", l_hull.Format().c_str());
+#endif
+
+
+	//printf("Pts: line %d hull %d\n", l_orig.PointCount(), l_hull.PointCount());
+
+	int first_post = -1;
+	int last_pre = -1;
+
+	for (int i = 0; i < l_orig.PointCount(); i++)
+	{
+		int ei =  l_hull.Find(l_orig.CPoint(i)) ;
+		bool edge = ei >= 0;
+		bool in = l_hull.PointInside( l_orig.CPoint(i)) && !edge;
+		bool out = !( in || edge);
+		
+		outside.push_back( out );
+		on_edge.push_back( edge );
+		inside.push_back( in );
+	}
+	
+
+	for(int i = l_orig.PointCount() - 1; i >= 1; i --)
+		if(inside[i] && outside[i-1])
+		{
+			SHAPE_LINE_CHAIN::Intersections ips;
+			l_hull.Intersect( SEG( l_orig.CPoint(i), l_orig.CPoint(i - 1) ), ips );
+			l_orig.Remove(i, -1);
+			l_orig.Append(ips[0].p);
+			break;
+		} 
+		else if (inside[i] && on_edge[i-1])
+		{	
+			l_orig.Remove(i, -1);
+			//n = i;
+		} else if(!inside[i])
+			break;
+
+	if(!outside.size() && on_edge.size() < 2)
+		return;
+
+	for (int i = 0; i < l_orig.PointCount(); i++)
+	{
+		const VECTOR2I p = l_orig.Point(i);
+		
+		if( outside[i] || (on_edge[i] && i == (l_orig.PointCount() - 1)))
+		{
+			if(last_pre	< 0)
+				aPrePath.Append(p);
+			path.Append(p);
+		}
+		else if ( on_edge[i] )
+		{
+			int li = -1;
+			if(last_pre < 0)
+			{
+				aPrePath.Append(p);
+				last_pre = path.PointCount();
+			}
+			if( i == l_orig.PointCount() - 1 || outside[i+1])
+			{
+				path.Append(p);
+			} 
+			else
+			{
+				int vi2 = l_hull.Find( l_orig.CPoint(i) );
+				
+				path.Append(l_hull.CPoint(vi2));
+				for(int j = (vi2 + 1) % l_hull.PointCount(); j != vi2; j = (j + 1) % l_hull.PointCount())
+				{
+					path.Append(l_hull.CPoint(j));
+					li = l_orig.Find(l_hull.CPoint(j));
+					if(li >= 0 && (li == (l_orig.PointCount() - 1) || outside[li+1]))
+						break;
+				}
+
+				if(li >= 0) {
+					if(i >= li)
+						break;
+					else {
+						i = li;	
+					}
+				}
+			}
+
+			first_post = path.PointCount() - 1;
+		}
+	}
+
+	if(last_pre < 0 && first_post < 0)
+		return;
+
+	aWalkaroundPath = path.Slice( last_pre, first_post );
+	if(first_post >= 0)
+		aPostPath = path.Slice( first_post, -1 );
+
+}
+
+bool PNS_LINE::onEdge(const SHAPE_LINE_CHAIN &obstacle, VECTOR2I p, int& ei, bool& is_vertex) const
+{
+		int vtx = obstacle.Find(p);
+
+		if(vtx >= 0)
+		{
+			ei = vtx;
+			is_vertex =true;
+			return true;
+		}
+		
+		for(int s = 0; s< obstacle.SegmentCount(); s++)
+		{
+			if(obstacle.CSegment(s).Contains(p))
+			{
+				ei = s;
+				is_vertex = false;
+				return true;
+			}
+		}
+
+	return false;
+}
+
+bool PNS_LINE::walkScan(const SHAPE_LINE_CHAIN &line, const SHAPE_LINE_CHAIN &obstacle, bool reverse, VECTOR2I &ip, int& index_o, int& index_l, bool& is_vertex) const
+{
+	int sc = line.SegmentCount();
+	for(int i = 0; i < line.SegmentCount(); i++)
+	{
+
+		printf("check-seg rev %d %d/%d %d\n",reverse, i, sc, sc - 1 - i);
+		SEG tmp = line.CSegment(reverse ? sc - 1 - i : i);
+		SEG s (tmp.a, tmp.b);
+		if(reverse)
+		{
+			s.a = tmp.b;
+			s.b = tmp.a;
+		}
+
+		if(onEdge(obstacle, s.a, index_o, is_vertex))
+		{
+			index_l = (reverse ?  sc-1-i : i);
+			ip = s.a;
+			printf("vertex %d on-%s %d\n", index_l, is_vertex?"vertex":"edge",index_o);
+			return true;
+		}
+
+		if(onEdge(obstacle, s.b, index_o, is_vertex))
+		{
+			index_l = (reverse?  sc-1-i-1 : i + 1);
+			ip = s.b;
+			printf("vertex %d on-%s %d\n", index_l, is_vertex?"vertex":"edge",index_o);
+			return true;
+		}
+
+		SHAPE_LINE_CHAIN::Intersections ips;
+		int n_is = obstacle.Intersect ( s, ips );
+
+		if (n_is > 0)
+		{
+			index_o = ips[0].our.Index();
+			index_l = reverse ?sc-1-i:i;
+			printf("segment-%d intersects edge-%d\n", index_l, index_o);
+			ip = ips[0].p;
+			return true;
+		}
+	}
+	return false;
+}
+
+bool PNS_LINE::Walkaround(SHAPE_LINE_CHAIN obstacle, SHAPE_LINE_CHAIN &pre, SHAPE_LINE_CHAIN &walk, SHAPE_LINE_CHAIN &post, bool cw) const
+{
+	const SHAPE_LINE_CHAIN &line = GetCLine();
+	VECTOR2I ip_start;
+	int index_o_start, index_l_start;
+	VECTOR2I ip_end;
+	int index_o_end, index_l_end;
+	
+	bool is_vertex_start, is_vertex_end;
+
+	if(line.SegmentCount() < 1)
+		return false;
+
+	if(obstacle.PointInside(line.CPoint(0)) || obstacle.PointInside(line.CPoint(-1)))
+		return false;	
+
+//	printf("forward:\n");
+	bool found = walkScan(line, obstacle, false, ip_start, index_o_start, index_l_start, is_vertex_start);
+	//printf("reverse:\n");
+	found |= walkScan(line, obstacle, true, ip_end, index_o_end, index_l_end, is_vertex_end);
+	
+	if(!found || ip_start == ip_end)
+	{
+		pre = line;
+		return true;
+	}
+
+
+	pre = line.Slice ( 0, index_l_start );
+	pre.Append (ip_start);
+	walk.Clear();
+	walk.Append(ip_start);
+
+	if(cw)
+	{
+		int is = (index_o_start + 1) % obstacle.PointCount();
+		int ie = (is_vertex_end ? index_o_end : index_o_end + 1) % obstacle.PointCount();
+
+		while(1)
+		{
+			printf("is %d\n", is);
+			walk.Append(obstacle.CPoint(is));		
+		
+			if(is == ie)
+				break;
+
+			is ++;
+			if (is == obstacle.PointCount() ) 
+				is = 0;
+		}
+	} else {
+		int is = index_o_start;
+		int ie = (is_vertex_end ? index_o_end : index_o_end) % obstacle.PointCount();
+
+		while(1) 
+		{
+			printf("is %d\n", is);
+			walk.Append(obstacle.CPoint(is));		
+			if(is == ie)
+				break;
+
+			is --;
+			if ( is < 0 ) 
+				is = obstacle.PointCount() - 1;
+		}
+
+
+	}
+
+	walk.Append(ip_end);
+	
+	post.Clear();
+	post.Append(ip_end);
+	post.Append(line.Slice (is_vertex_end ? index_l_end : index_l_end + 1 , -1));
+	
+	//for(int i = (index_o_start + 1) % obstacle.PointCount();
+	//	i != (index_o_end + 1) % obstacle.PointCount(); i=(i+1) % obstacle.PointCount())
+	//{
+		//printf("append %d\n", i);
+		//walk.Append(obstacle.CPoint(i));
+	//}
+
+	return true;
+
+}
+
+
+
+void PNS_LINE::NewWalkaround( const SHAPE_LINE_CHAIN& aObstacle, 
+ 							  SHAPE_LINE_CHAIN& aPath,
+					 		  bool aCw ) const
+{
+	SHAPE_LINE_CHAIN walk, post;
+	NewWalkaround(aObstacle, aPath, walk, post, aCw);
+	aPath.Append(walk);
+	aPath.Append(post);
+	aPath.Simplify();
+}
+
+void PNS_LINE::Walkaround( const SHAPE_LINE_CHAIN& aObstacle, 
+ 							  SHAPE_LINE_CHAIN& aPath,
+					 		  bool aCw ) const
+{
+	SHAPE_LINE_CHAIN walk, post;
+	Walkaround(aObstacle, aPath, walk, post, aCw);
+	aPath.Append(walk);
+	aPath.Append(post);
+	aPath.Simplify();
+}
+
+
+const SHAPE_LINE_CHAIN PNS_SEGMENT::Hull(int aClearance, int aWalkaroundThickness) const
+{
+	int d = aClearance + 10;
+	int x = (int) (2.0 / (1.0 + M_SQRT2) * d) + 2;
+
+	const VECTOR2I a = m_shape.CPoint(0);
+	const VECTOR2I b = m_shape.CPoint(1);
+	
+	VECTOR2I dir = b - a;
+
+	VECTOR2I p0 = dir.Perpendicular().Resize(d);
+
+	
+	VECTOR2I ds = dir.Perpendicular().Resize(x / 2);
+	VECTOR2I pd = dir.Resize(x / 2);
+	VECTOR2I dp = dir.Resize(d);
+
+
+	SHAPE_LINE_CHAIN s;
+	s.SetClosed( true );
+
+	s.Append(b + p0 + pd);
+	s.Append(b + dp + ds);
+	s.Append(b + dp - ds);
+	s.Append(b - p0 + pd);
+	s.Append(a - p0 - pd);
+	s.Append(a - dp - ds);
+	s.Append(a - dp + ds);
+	s.Append(a + p0 - pd);
+	
+	// make sure the hull outline is always clockwise
+	if(s.CSegment(0).Side(a) < 0)
+		return s.Reverse();
+	else
+		return s;
+
+}
+
+
+bool PNS_LINE::Is45Degree()
+{
+	for(int i = 0; i < m_line.SegmentCount(); i++)
+	{
+		const SEG &s = m_line.CSegment(i);
+
+		double angle = 180.0 / M_PI * atan2((double)s.b.y - (double)s.a.y, (double)s.b.x - (double)s.a.x);
+		
+		if(angle < 0)
+			angle+=360.0;
+
+		double angle_a = fabs(fmod(angle, 45.0));
+		if(angle_a > 1.0 && angle_a < 44.0)
+			return false;
+	}
+	return true;
+}
+
+const PNS_LINE PNS_LINE::ClipToNearestObstacle( PNS_NODE *aNode ) const
+{
+	PNS_LINE l (*this);
+
+	PNS_NODE::OptObstacle obs = aNode->NearestObstacle ( &l );
+
+	if(obs)
+	{
+		l.RemoveVia();
+		int p = l.GetLine().Split(obs -> ip_first);
+		l.GetLine().Remove(p + 1, -1);
+	}
+
+	return l;
+}
+
+void PNS_LINE::ShowLinks()
+{
+	if(!m_segmentRefs)
+	{
+		printf("line %p: no links\n", this);
+		return;
+	}
+		printf("line %p: %d linked segs\n", this, m_segmentRefs->size());
+		for (int i= 0; i<(int)m_segmentRefs->size(); i++) printf("seg %d: %p\n", i, (*m_segmentRefs)[i])	;
+}

pcbnew/router/pns_line.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_LINE_H
+#define __PNS_LINE_H
+
+#include <math/vector2d.h>
+
+#include <geometry/seg.h>
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+
+#include "direction.h"
+#include "pns_item.h"
+#include "pns_via.h"
+
+class PNS_NODE;
+class PNS_SEGMENT;
+class PNS_VIA;
+
+/**
+ * Class PNS_LINE
+ *
+ * Represents a track on a PCB, connecting two non-trivial joints (that is, vias, pads, 
+ * junctions between multiple traces or two traces different widths and combinations of these).
+ * PNS_LINEs are NOT stored in the model (PNS_NODE) - instead, they are assembled on-the-fly, based on 
+ * a via/pad/segment that belongs/begins them.
+ *
+ * PNS_LINEs can be either loose (consisting of segments that do not belong to any PNS_NODE) or owned (with segments
+ * taken from a PNS_NODE) - these are returned by PNS_NODE::AssembleLine and friends.
+ * 
+ * A PNS_LINE may have a PNS_VIA attached at its and - this is used by via dragging/force propagation stuff.
+ */
+
+class PNS_LINE : public PNS_ITEM 
+{
+public:
+	typedef std::vector<PNS_SEGMENT *> LinkedSegments;
+
+	PNS_LINE ():
+		PNS_ITEM(LINE)
+		{
+				m_segmentRefs = NULL;
+				m_hasVia = false;
+				m_affectedRangeStart = -1;
+		};
+
+	PNS_LINE (int aLayer, int aWidth, const SHAPE_LINE_CHAIN& aLine) : 
+		PNS_ITEM(LINE)
+			{
+				m_line = aLine;
+				m_width = aWidth;
+				m_segmentRefs = NULL;
+				m_hasVia = false;
+				m_affectedRangeStart = -1;
+				SetLayer(aLayer);
+
+			}
+
+	PNS_LINE(const PNS_LINE& aOther) :
+		PNS_ITEM(aOther), 
+		m_line(aOther.m_line), 
+		m_width(aOther.m_width)
+	{
+		m_net = aOther.m_net;	
+		m_movable = aOther.m_movable;
+		m_world = aOther.m_world;
+		m_layers = aOther.m_layers;
+		m_segmentRefs = NULL;
+		m_via = aOther.m_via;
+		m_hasVia = aOther.m_hasVia;
+		m_affectedRangeStart = -1;
+	}
+
+	/**
+	 * Constructor
+	 * copies properties (net, layers from a base line), and replaces the shape
+	 * by aLine 
+	 **/
+	PNS_LINE(const PNS_LINE& aBase, const SHAPE_LINE_CHAIN& aLine) :
+		PNS_ITEM(aBase),
+		m_line(aLine), 
+		m_width(aBase.m_width) 
+	{
+		m_net = aBase.m_net;
+		m_layers = aBase.m_layers;
+		m_segmentRefs = NULL;
+		m_hasVia = false;
+		m_affectedRangeStart = -1;
+	}	
+
+	~PNS_LINE ()
+	{
+		if(m_segmentRefs)
+			delete m_segmentRefs;
+	};
+	
+	virtual PNS_LINE *Clone() const ;
+	
+	///> clones the line without cloning the shape (just the properties - net, width, layers, etc.)
+	PNS_LINE *CloneProperties() const ;
+	
+	int GetLayer() const { return GetLayers().Start(); }
+
+	///> Geometry accessors
+	void SetShape(const SHAPE_LINE_CHAIN& aLine) 		{ m_line = aLine; }
+	const SHAPE* GetShape() const  						{ return &m_line; }
+	SHAPE_LINE_CHAIN& GetLine() 						{ return m_line; }
+	const SHAPE_LINE_CHAIN& GetCLine() const 			{ return m_line; }
+
+	///> Width accessors
+	void SetWidth( int aWidth ) 						{ m_width = aWidth; }
+	int GetWidth () const 								{ return m_width; }
+
+	///> Links a segment from a PNS_NODE to this line, making it owned by the node
+	void LinkSegment(PNS_SEGMENT *aSeg)
+	{
+		if(!m_segmentRefs)
+			m_segmentRefs = new std::vector<PNS_SEGMENT *> ();
+		m_segmentRefs->push_back(aSeg);
+	}
+
+	///> Returns a list of segments from the owning node that constitute this line (or NULL if
+	///> the line is loose)
+	LinkedSegments* GetLinkedSegments() 
+	{
+		return m_segmentRefs;
+	}
+
+	bool ContainsSegment (PNS_SEGMENT *aSeg) const
+	{
+		if (!m_segmentRefs)
+			return false;
+
+		return std::find( m_segmentRefs->begin(), m_segmentRefs->end(), aSeg) != m_segmentRefs->end();
+	}
+
+	///> Returns this line, but clipped to the nearest obstacle along, to avoid collision.
+	const PNS_LINE ClipToNearestObstacle( PNS_NODE *aNode ) const;
+	
+	///> DEPRECATED optimization functions (moved to PNS_OPTIMIZER)
+	bool MergeObtuseSegments();
+	bool MergeSegments();
+	
+	///> Returns the number of corners of angles specified by mask aAngles.
+	int CountCorners(int aAngles);
+
+
+	///> Calculates a line thightly wrapping a convex hull of an obstacle object (aObstacle).
+	///> aPrePath = path from origin to the obstacle
+	///> aWalkaroundPath = path around the obstacle
+	///> aPostPath = past from obstacle till the end
+	///> aCW = whether to walkaround in clockwise or counter-clockwise direction.
+	void NewWalkaround( const SHAPE_LINE_CHAIN& aObstacle, 
+ 							  SHAPE_LINE_CHAIN& aPrePath,
+					 		  SHAPE_LINE_CHAIN& aWalkaroundPath,
+					 		  SHAPE_LINE_CHAIN& aPostPath,
+					 		  bool aCw ) const;
+
+	void NewWalkaround( const SHAPE_LINE_CHAIN& aObstacle, 
+ 							  SHAPE_LINE_CHAIN& aPath,
+					 		  bool aCw ) const;
+	
+	
+	bool Walkaround(SHAPE_LINE_CHAIN obstacle, SHAPE_LINE_CHAIN &pre, SHAPE_LINE_CHAIN &walk, SHAPE_LINE_CHAIN &post, bool cw) const;
+
+	void Walkaround( const SHAPE_LINE_CHAIN& aObstacle, 
+ 							  SHAPE_LINE_CHAIN& aPath,
+					 		  bool aCw ) const;
+	
+
+	bool Is45Degree();
+
+	///> Prints out all linked segments	
+	void ShowLinks();
+
+	bool EndsWithVia() const {	return m_hasVia; }
+	
+	void AppendVia ( const PNS_VIA &aVia ) {
+		m_hasVia = true;
+		m_via = aVia;
+		m_via.SetNet ( m_net ) ;
+	}
+
+	void RemoveVia() 				{ m_hasVia = false; }
+	const PNS_VIA& GetVia() const 	{ return m_via; }
+
+	void SetAffectedRange ( int aStart, int aEnd )
+	{
+		m_affectedRangeStart = aStart;
+		m_affectedRangeEnd = aEnd;
+	}
+
+	void ClearAffectedRange ( )
+	{
+		m_affectedRangeStart = -1;
+	}
+
+	bool GetAffectedRange ( int& aStart, int& aEnd )
+	{
+		if(m_affectedRangeStart >= 0)
+		{
+			aStart = m_affectedRangeStart;
+			aEnd = m_affectedRangeEnd;
+			return true;
+		} else {
+			aStart = 0;
+			aEnd = m_line.PointCount();
+			return false;
+		}
+	}
+
+private:
+	bool onEdge(const SHAPE_LINE_CHAIN &obstacle, VECTOR2I p, int& ei, bool& is_vertex) const;
+	bool walkScan(const SHAPE_LINE_CHAIN &line, const SHAPE_LINE_CHAIN &obstacle, bool reverse, VECTOR2I &ip, int& index_o, int& index_l, bool& is_vertex) const;
+	
+	///> List of semgments in a PNS_NODE (PNS_ITEM::m_owner) that constitute this line.
+	LinkedSegments* m_segmentRefs;
+	
+	///> Shape of the line
+	SHAPE_LINE_CHAIN m_line;
+	
+	int m_width;
+	///> Via at the end and a flag indicating if it's enabled.
+	PNS_VIA m_via;
+	bool m_hasVia;
+
+	int m_affectedRangeStart;
+	int m_affectedRangeEnd;
+};
+
+
+#endif // __PNS_LINE_H
+

pcbnew/router/pns_line_placer.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <vector>
+#include <boost/foreach.hpp>
+#include <boost/optional.hpp>
+
+#include "trace.h"
+
+#include "pns_node.h"
+#include "pns_line_placer.h"
+#include "pns_walkaround.h"
+#include "pns_shove.h"
+#include "pns_utils.h"
+
+using namespace std;
+using boost::optional;
+
+PNS_LINE_PLACER::PNS_LINE_PLACER( PNS_NODE *aWorld )
+{
+	m_initial_direction = DIRECTION_45(DIRECTION_45::N);
+	m_follow_mouse = false;
+	m_smoothing_step = 100000;
+	m_smooth_mouse = false;
+	m_iteration = 0;
+	m_world =  aWorld;
+	m_mode = RM_Smart;
+	m_follow_mouse = true;
+	m_shove = NULL;
+};
+
+PNS_LINE_PLACER::~PNS_LINE_PLACER() 
+{
+	if(m_shove)
+		delete m_shove;		
+}
+	
+void PNS_LINE_PLACER::ApplySettings ( const PNS_ROUTING_SETTINGS& aSettings )
+{
+	m_follow_mouse = aSettings.m_followMouse;
+	m_mode = aSettings.m_routingMode;
+	m_walkaroundIterationLimit = aSettings.m_walkaroundIterationLimit;
+	m_smartPads = aSettings.m_smartPads;
+}
+
+void PNS_LINE_PLACER::StartPlacement(const VECTOR2I& aStart, int aNet, int aWidth, int aLayer )
+{
+	m_direction = m_initial_direction;
+	TRACE(1, "world %p, intitial-direction %s layer %d\n", m_world % m_direction.Format().c_str() % aLayer);
+	m_head.SetNet(aNet);
+	m_tail.SetNet(aNet);
+	m_head.SetWidth(aWidth);
+	m_tail.SetWidth(aWidth);
+	m_head.GetLine().Clear();
+	m_tail.GetLine().Clear();			
+	m_head.SetLayer(aLayer);
+	m_tail.SetLayer(aLayer);
+	m_iteration = 0;
+	m_p_start = aStart;
+	m_currentNode = m_world->Branch();
+	m_head.SetWorld(m_currentNode);
+	m_tail.SetWorld(m_currentNode);
+	//if(m_shove)
+	//	delete m_shove;
+	m_shove = new PNS_SHOVE(m_currentNode);
+	m_placingVia = false;
+}
+	
+void PNS_LINE_PLACER::SetInitialDirection(const DIRECTION_45& aDirection)
+{
+	m_initial_direction = aDirection;
+
+	if(m_tail.GetCLine().SegmentCount() == 0)
+		m_direction = aDirection;
+}
+
+/**
+ * Function handleSelfIntersections()
+ *
+ * Checks if the head of the track intersects its tail. If so, cuts the tail up to the
+ * intersecting segment and fixes the head direction to match the last segment before the cut.
+ * @return true if the line has been changed.
+ */
+bool PNS_LINE_PLACER::handleSelfIntersections() 
+{
+	SHAPE_LINE_CHAIN::Intersections ips;
+	SHAPE_LINE_CHAIN& head = m_head.GetLine();
+	SHAPE_LINE_CHAIN& tail = m_tail.GetLine();
+
+	// if there is no tail, there is nothing to intersect with			
+	if(tail.PointCount() < 2)
+		return false;
+
+	tail.Intersect(head, ips);
+		
+	// no intesection points - nothing to reduce
+	if (ips.empty())
+		return false;
+		
+	int n = INT_MAX;
+	VECTOR2I ipoint;
+
+	// if there is more than one intersection, find the one that is
+	// closest to the beginning of the tail.
+	BOOST_FOREACH(SHAPE_LINE_CHAIN::Intersection i, ips)
+	{
+		if (i.our.Index() < n)
+		{
+			n = i.our.Index();
+			ipoint = i.p;
+		}
+	}
+
+	// ignore the point where head and tail meet
+	if(ipoint == head.CPoint(0) || ipoint == tail.CPoint(-1))
+		return false;
+
+	// Intersection point is on the first or the second segment: just start routing
+	// from the beginning
+	if (n < 2)
+	{
+		m_p_start = tail.Point(0);
+		m_direction = m_initial_direction;
+		tail.Clear();
+		head.Clear();
+		return true;
+	} else {
+		// Clip till the last tail segment before intersection. 
+		// Set the direction to the one of this segment.
+		const SEG last = tail.CSegment(n - 1); 
+		m_p_start = last.a; 
+		m_direction = DIRECTION_45(last);
+		tail.Remove(n, -1); 
+		return true;
+	}
+	return false;
+}				
+
+/**
+ * Function handlePullback()
+ * 
+ * Deals with pull-back: reduces the tail if head trace is moved backwards wrs 
+ * to the current tail direction.
+ * @return true if the line has been changed.
+ */
+bool PNS_LINE_PLACER::handlePullback() 
+{
+	SHAPE_LINE_CHAIN& head = m_head.GetLine();
+	SHAPE_LINE_CHAIN& tail = m_tail.GetLine();
+		
+	int n = tail.PointCount();
+
+	if(n == 0)
+		return false;
+	else if (n == 1)
+	{
+		m_p_start = tail.CPoint(0);
+		tail.Clear();
+		return true;
+	}
+	
+	DIRECTION_45 first_head (head.Segment(0));
+	DIRECTION_45 last_tail (tail.Segment(-1));
+	DIRECTION_45::AngleType angle = first_head.Angle(last_tail);
+
+	// case 1: we have a defined routing direction, and the currently computed head
+	// goes in different one. 
+	bool pullback_1 = false;//(m_direction != DIRECTION_45::UNDEFINED && m_direction != first_head);
+	
+	// case 2: regardless of the current routing direction, if the tail/head extremities form
+	// an acute or right angle, reduce the tail by one segment (and hope that further iterations)
+	// will result with a cleaner trace
+	bool pullback_2 = (angle == DIRECTION_45::ANG_RIGHT || angle == DIRECTION_45::ANG_ACUTE);
+
+	if(pullback_1 || pullback_2)
+	{
+	
+		const SEG last = tail.CSegment(-1);
+		m_direction = DIRECTION_45(last);
+		m_p_start = last.a;
+
+	
+		TRACE(0, "Placer: pullback triggered [%d] [%s %s]", n % last_tail.Format().c_str() % first_head.Format().c_str());
+		// erase the last point in the tail, hoping that the next iteration will result with a head
+		// trace that starts with a segment following our current direction. 
+		if(n < 2)
+			tail.Clear(); // don't leave a single-point tail
+		else
+			tail.Remove(-1, -1);
+
+		if( !tail.SegmentCount() )
+			m_direction = m_initial_direction;
+
+		return true;
+	} 
+
+	return false;
+}
+
+/**
+ * Function reduceTail()
+ * 
+ * Attempts to reduce the numer of segments in the tail by trying to replace a certain number
+ * of latest tail segments with a direct trace leading to aEnd that does not collide with anything.
+ * @param aEnd: current routing destination point.
+ * @return true if the line has been changed.
+ */
+bool PNS_LINE_PLACER::reduceTail(const VECTOR2I& aEnd)
+{
+	SHAPE_LINE_CHAIN& head = m_head.GetLine();
+	SHAPE_LINE_CHAIN& tail = m_tail.GetLine();
+	
+	int n = tail.SegmentCount();
+	
+	// Don't attempt this for too short tails	
+	if (n < 2)
+		return false;
+
+	// Start from the segment farthest from the end of the tail
+	//int start_index = std::max(n - 1 - ReductionDepth, 0); 
+		
+	DIRECTION_45 new_direction;
+	VECTOR2I new_start;
+	int reduce_index = -1;
+
+	DIRECTION_45 head_dir ( head.Segment(0) );
+
+	for(int i = tail.SegmentCount() - 1; i >= 0; i--)
+	{
+		const SEG s = tail.CSegment(i);
+		DIRECTION_45 dir (s); 
+
+		// calculate a replacement route and check if it matches the direction of the segment to be replaced
+		SHAPE_LINE_CHAIN replacement = dir.BuildInitialTrace(s.a, aEnd);
+		
+			PNS_LINE tmp (m_tail, replacement);
+
+			if (m_currentNode->CheckColliding(&tmp, PNS_ITEM::ANY))
+				break;
+				
+			if(DIRECTION_45(replacement.Segment(0)) == dir)
+			{	
+				new_start = s.a;
+				new_direction = dir;
+				reduce_index = i;
+			} 
+	}
+
+	if(reduce_index >= 0)
+	{
+
+		TRACE(0, "Placer: reducing tail: %d", reduce_index);
+		SHAPE_LINE_CHAIN reducedLine = new_direction.BuildInitialTrace(new_start, aEnd); 
+
+		m_p_start = new_start;
+		m_direction = new_direction;
+		tail.Remove(reduce_index+1, -1);
+		head.Clear();
+		return true;
+	}
+
+	if( !tail.SegmentCount() )
+		m_direction = m_initial_direction;
+
+	return false;
+}
+
+
+/**
+ * Function checkObtusity()
+ *
+ * Helper that checks if segments a and b form an obtuse angle (in 45-degree regime).
+ * @return true, if angle (a, b) is obtuse
+ */
+bool PNS_LINE_PLACER::checkObtusity(const SEG& a, const SEG& b) const
+{
+	const DIRECTION_45 dir_a(a);
+	const DIRECTION_45 dir_b(b);
+	return dir_a.IsObtuse(dir_b) || dir_a == dir_b;
+}
+
+
+/**
+ * Function mergeHead()
+ *
+ * Moves "estabished" segments from the head to the tail if certain conditions are met.
+ * @return true, if the line has been changed.
+ */
+bool PNS_LINE_PLACER::mergeHead()
+{
+	SHAPE_LINE_CHAIN& head = m_head.GetLine();
+	SHAPE_LINE_CHAIN& tail = m_tail.GetLine();
+
+	const int ForbiddenAngles = DIRECTION_45::ANG_ACUTE | DIRECTION_45::ANG_HALF_FULL | DIRECTION_45::ANG_UNDEFINED;
+
+	head.Simplify();
+	tail.Simplify();
+
+	int n_head = head.SegmentCount();
+	int n_tail = tail.SegmentCount();
+
+	if( n_head < 3 )
+	{
+		TRACEn(4, "Merge failed: not enough head segs.");
+		return false;
+	}
+
+	if (n_tail && head.CPoint(0) != tail.CPoint(-1))
+	{
+		TRACEn(4, "Merge failed: head and tail discontinuous.");
+		return false;
+	}
+
+	if( m_head.CountCorners(ForbiddenAngles) != 0 )
+		return false;
+
+	DIRECTION_45 dir_tail, dir_head;
+
+	dir_head = DIRECTION_45(head.CSegment(0));
+
+	if(n_tail)
+	{
+		dir_tail = DIRECTION_45(tail.CSegment(-1));
+		if(dir_head.Angle(dir_tail) & ForbiddenAngles)
+			return false;
+	}
+
+	if(!n_tail)
+		tail.Append(head.CSegment(0).a);
+
+	for (int i = 0; i < n_head - 2; i++)
+	{
+		tail.Append(head.CSegment(i).b);
+	}
+
+	tail.Simplify();
+
+	SEG last = tail.CSegment(-1);
+	
+	m_p_start = last.b;
+	m_direction = DIRECTION_45(last).Right();
+
+
+	head.Remove(0, n_head - 2);
+
+	TRACE(0, "Placer: merge %d, new direction: %s", n_head % m_direction.Format().c_str());
+	
+
+	head.Simplify();
+	tail.Simplify();
+
+	return true;
+}
+
+bool PNS_LINE_PLACER::handleViaPlacement ( PNS_LINE& aHead )
+{
+	if(!m_placingVia)
+		return true;
+
+	PNS_LAYERSET allLayers (0, 15);
+	PNS_VIA v (aHead.GetCLine().CPoint(-1), allLayers, m_viaDiameter, aHead.GetNet());
+	v.SetDrill(m_viaDrill);
+
+	VECTOR2I force;
+	VECTOR2I lead = aHead.GetCLine().CPoint(-1) - aHead.GetCLine().CPoint(0);
+
+	
+	if( v.PushoutForce ( m_shove->GetCurrentNode(), lead, force, true, 20 ) )
+	{
+		SHAPE_LINE_CHAIN line = m_direction.BuildInitialTrace(aHead.GetCLine().CPoint(0), aHead.GetCLine().CPoint(-1) + force); 
+		aHead = PNS_LINE(aHead, line);
+
+		v.SetPos(v.GetPos() + force);
+		return true;
+	}
+	
+	return false;
+}
+
+/**
+ * Function routeHead()
+ *
+ * Computes the head trace between the current start point (m_p_start) and point aP,
+ * starting with direction defined in m_direction. The trace walks around all
+ * colliding solid or non-movable items. Movable segments are ignored, as they'll be handled
+ * later by the shove algorithm.
+ */
+bool PNS_LINE_PLACER::routeHead(const VECTOR2I& aP, PNS_LINE& aNewHead, bool aCwWalkaround)
+{
+	// STAGE 1: route a simple two-segment trace between m_p_start and aP...
+	SHAPE_LINE_CHAIN line = m_direction.BuildInitialTrace(m_p_start, aP); 
+
+	PNS_LINE initTrack (m_head, line);
+	PNS_LINE walkFull, walkSolids;
+
+
+	if(m_mode == RM_Ignore)
+	{
+		aNewHead = initTrack;
+		return true;
+	}
+	handleViaPlacement(initTrack);
+
+	m_currentNode = m_shove->GetCurrentNode();
+
+	PNS_OPTIMIZER optimizer(m_currentNode);
+	PNS_WALKAROUND walkaround( m_currentNode );
+
+	walkaround.SetSolidsOnly(false);
+	walkaround.SetIterationLimit(m_mode == RM_Walkaround ? 8 : 5 );
+	//walkaround.SetApproachCursor(true, aP);
+	
+	PNS_WALKAROUND::WalkaroundStatus wf = walkaround.Route(initTrack, walkFull);
+
+#if 0
+	
+	if(m_mode == RM_Walkaround)
+	{
+	//	walkaround.		
+//		PNSDisplayDebugLine (walkFull.GetCLine(), 4);
+
+		if(wf == PNS_WALKAROUND::STUCK)
+		{
+			aNewHead = m_head;
+			aNewHead.SetShape(walkFull.GetCLine());
+			aNewHead = aNewHead.ClipToNearestObstacle(m_currentNode);
+			return false;
+		}
+			
+		aNewHead = m_head;
+		aNewHead.SetShape(walkFull.GetCLine());
+
+//		printf("nh w %d l %d\n", aNewHead.GetWidth(), aNewHead.GetLayers().Start());
+		return true;
+	}
+#endif
+
+	PNS_COST_ESTIMATOR cost_walk, cost_orig;
+	
+	walkaround.SetApproachCursor ( false, aP );
+	walkaround.SetSolidsOnly(true);
+	walkaround.SetIterationLimit( 10 );
+	PNS_WALKAROUND::WalkaroundStatus stat_solids = walkaround.Route(initTrack, walkSolids);
+
+	optimizer.SetEffortLevel ( PNS_OPTIMIZER::MERGE_SEGMENTS );
+	optimizer.SetCollisionMask (PNS_ITEM::SOLID);
+	optimizer.Optimize(&walkSolids);
+	#if 0
+		optimizer.SetCollisionMask (-1);
+		optimizer.Optimize(&walkFull);
+	#endif
+	cost_orig.Add(initTrack);
+	cost_walk.Add(walkFull);
+
+	if(m_mode == RM_Smart || m_mode == RM_Shove)
+	{
+		PNS_LINE l2;
+
+		bool walk_better = cost_orig.IsBetter(cost_walk, 1.5, 10.0);
+		walk_better = false;
+
+#if 0
+		printf("RtTrk width %d %d %d", initTrack.GetWidth(), walkFull.GetWidth(), walkSolids.GetWidth());
+		printf("init-coll %d\n", m_currentNode->CheckColliding(&initTrack)? 1: 0);
+		printf("total cost: walk cor %.0f len %.0f orig cor %.0f len %.0f walk-better %d\n", 
+			cost_walk.GetCornerCost(), cost_walk.GetLengthCost(),
+			cost_orig.GetCornerCost(), cost_orig.GetLengthCost(),
+			walk_better );
+#endif
+
+		if(m_mode == RM_Smart && wf == PNS_WALKAROUND::DONE && walk_better && walkFull.GetCLine().CPoint(-1) == initTrack.GetCLine().CPoint(-1))
+			l2 = walkFull;
+		else if (stat_solids == PNS_WALKAROUND::DONE)
+			l2 = walkSolids;
+		else
+			l2 = initTrack.ClipToNearestObstacle(m_shove->GetCurrentNode());
+
+		PNS_LINE l ( m_tail );
+		l.GetLine().Append( l2.GetCLine() );
+		l.GetLine().Simplify();
+
+		if(m_placingVia)
+		{
+			PNS_LAYERSET allLayers(0,15);
+			PNS_VIA v1( l.GetCLine().CPoint(-1), allLayers, m_viaDiameter );
+			PNS_VIA v2( l2.GetCLine().CPoint(-1), allLayers, m_viaDiameter );
+			v1.SetDrill(m_viaDrill);
+			v2.SetDrill(m_viaDrill);
+			
+			l.AppendVia ( v1 );
+			l2.AppendVia ( v2 );
+		}
+
+		PNS_SHOVE::ShoveStatus status = m_shove->ShoveLines(&l);
+		m_currentNode = m_shove->GetCurrentNode();
+
+		if (status == PNS_SHOVE::SH_OK)
+		{
+			
+			optimizer.SetWorld (m_currentNode);
+			optimizer.ClearCache();
+			optimizer.SetEffortLevel( PNS_OPTIMIZER::MERGE_OBTUSE | PNS_OPTIMIZER::SMART_PADS );
+			optimizer.SetCollisionMask (-1);
+			optimizer.Optimize(&l2);
+			
+			aNewHead = l2; 
+		
+			return true;
+		} else {
+			walkaround.SetWorld( m_currentNode );
+			walkaround.SetSolidsOnly(false);
+			walkaround.SetIterationLimit( 10 );
+			walkaround.SetApproachCursor ( true, aP );
+			walkaround.Route(initTrack, l2);
+			aNewHead = l2.ClipToNearestObstacle (m_shove->GetCurrentNode());
+			//aNewHead = l2;
+			
+			return false;
+		}
+		
+	}
+
+	return false;
+}
+
+
+/**
+ * Function optimizeTailHeadTransition()
+ *
+ * Tries to reduce the corner count of the most recent part of tail/head by merging
+ * obtuse/collinear segments.
+ * @return true, if the line has been changed.
+ */
+bool PNS_LINE_PLACER::optimizeTailHeadTransition()
+{
+	SHAPE_LINE_CHAIN& head = m_head.GetLine();
+	SHAPE_LINE_CHAIN& tail = m_tail.GetLine();
+
+	const int TailLookbackSegments = 5;
+	
+	int threshold = min(tail.PointCount(), TailLookbackSegments + 1);
+	
+	if(tail.SegmentCount() < 3)
+		return false;
+
+	// assemble TailLookbackSegments tail segments with the current head
+	SHAPE_LINE_CHAIN opt_line = tail.Slice(-threshold, -1);
+
+	opt_line.Append(head);
+//	opt_line.Simplify();
+
+	PNS_LINE new_head(m_tail, opt_line);
+	
+	// and see if it could be made simpler by merging obtuse/collnear segments. If so,
+	// replace the (threshold) last tail points and the head with the optimized line
+
+	//if(PNS_OPTIMIZER::Optimize(&new_head, PNS_OPTIMIZER::MERGE_SEGMENTS))
+
+
+	if(new_head.MergeSegments())
+	{
+		PNS_LINE tmp(m_tail, opt_line);
+		
+		TRACE(0, "Placer: optimize tail-head [%d]", threshold);
+				
+		head.Clear();
+		tail.Replace(-threshold, -1, new_head.GetCLine());
+		tail.Simplify();
+
+		m_p_start = new_head.GetCLine().CPoint(-1);
+		m_direction = DIRECTION_45(new_head.GetCLine().CSegment(-1));
+
+		return true;
+	}
+
+	return false;	
+}
+
+/**
+ * Function routeStep()
+ *
+ * Performs a single routing alorithm step, for the end point aP. 
+ * @param aP ending point of current route
+ * @return true, if the line has been changed.
+ */
+
+
+void PNS_LINE_PLACER::routeStep(const VECTOR2I& aP)
+{
+	bool fail = false;
+	bool go_back = false;
+	
+	int i, n_iter = 1;
+
+	PNS_LINE new_head;
+	
+	m_follow_mouse = true;
+
+	TRACE(2,"INIT-DIR: %s head: %d, tail: %d segs\n", m_initial_direction.Format().c_str() % m_head.GetCLine().SegmentCount() % m_tail.GetCLine().SegmentCount());
+
+	for(i = 0; i < n_iter; i++)
+	{
+		
+		if(!go_back && m_follow_mouse)
+			reduceTail(aP);
+		
+		go_back = false;
+
+		if(!routeHead(aP, new_head, true))
+			fail = true;
+				
+		if(!new_head.Is45Degree())
+			fail = true;
+		
+		if(!m_follow_mouse)
+			return;
+		
+		m_head = new_head;
+
+		if(handleSelfIntersections())
+		{
+			n_iter++;
+			go_back = true;
+		}
+
+		if(!go_back && handlePullback())
+		{
+			n_iter++;
+			go_back = true;
+		}
+	}
+
+	if(!fail)
+	{
+		if(optimizeTailHeadTransition())
+			return; 
+	 	mergeHead();
+	}
+		
+}
+
+/**
+ * Function Route()
+ *
+ * Re-routes the current track to point aP. Returns true, when routing has completed
+ * successfully (i.e. the trace end has reached point aP), and false if the trace was stuck somewhere
+ * on the way. May call routeStep() repetitively due to mouse smoothing.
+ * @param aP ending point of current route.
+ * @return true, if the routing is complete. 
+ */
+bool PNS_LINE_PLACER::Route(const VECTOR2I& aP)
+{
+	if(m_smooth_mouse)	
+	{
+		VECTOR2I p_cur = m_p_start;
+		VECTOR2I step = (aP - m_p_start).Resize(m_smoothing_step);
+
+		do
+		{
+			if ((p_cur - aP).EuclideanNorm() <= m_smoothing_step)
+				p_cur = aP;
+			else
+				p_cur += step;
+
+			routeStep(p_cur);
+
+		} while (p_cur != aP);
+	} else 
+		routeStep(aP);
+
+	return CurrentEnd() == aP;
+}
+
+
+const PNS_LINE PNS_LINE_PLACER::GetTrace() const
+{
+	PNS_LINE tmp(m_head);
+	tmp.SetShape( m_tail.GetCLine() );
+	tmp.GetLine().Append( m_head.GetCLine() );
+	tmp.GetLine().Simplify();
+	return tmp;
+}
+
+void PNS_LINE_PLACER::FlipPosture()
+{
+	m_initial_direction = m_initial_direction.Right();
+	m_direction = m_direction.Right();
+}	
+
+void PNS_LINE_PLACER::GetUpdatedItems( PNS_NODE::ItemVector& aRemoved,  PNS_NODE::ItemVector& aAdded)
+{
+	return m_shove->GetCurrentNode()->GetUpdatedItems(aRemoved, aAdded);
+}
+
+PNS_NODE *PNS_LINE_PLACER::GetCurrentNode() const
+{
+	return m_shove->GetCurrentNode();
+}
\ No newline at end of file

pcbnew/router/pns_line_placer.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_LINE_PLACER_H
+#define __PNS_LINE_PLACER_H
+
+#include <math/vector2d.h>
+
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+
+#include "pns_node.h"
+#include "pns_via.h"
+#include "pns_line.h"
+#include "pns_routing_settings.h"
+ 
+class PNS_ROUTER;
+class PNS_SHOVE;
+class PNS_OPTIMIZER;
+class PNS_ROUTER_BASE;
+
+/**
+ * Class PNS_LINE_PLACER
+ *
+ * Interactively routes a single track. Runs shove and walkaround algorithms when needed.
+ */
+
+class PNS_LINE_PLACER
+{
+	public:
+		PNS_LINE_PLACER( PNS_NODE *aWorld );
+		~PNS_LINE_PLACER();
+
+		///> Appends a via at the end of currently placed line.		
+		void AddVia ( bool aEnabled, int aDiameter, int aDrill )
+		{
+			m_viaDiameter = aDiameter;
+			m_viaDrill = aDrill;
+			m_placingVia = aEnabled;
+		}
+
+		///> Starts placement of a line at point aStart.
+		void StartPlacement(const VECTOR2I& aStart, int aNet, int aWidth, int aLayer);
+		
+		///> Updates the routed line with a new ending point.
+		bool Route(const VECTOR2I& aP);
+		
+		///> Sets initial routing direction/posture
+		void SetInitialDirection(const DIRECTION_45& aDirection);
+		
+		void ApplySettings ( const PNS_ROUTING_SETTINGS& aSettings );
+
+		///> Returns the "head" of the line being placed, that is the volatile part that has not been settled yet
+		const PNS_LINE& GetHead() const	{ return m_head; }
+		///> Returns the "tail" of the line being placed the part that has been fixed already (follow mouse mode only)
+		const PNS_LINE& GetTail() const { return m_tail; }
+
+		///> Returns the whole routed line
+		const PNS_LINE GetTrace() const;
+
+		///> Returns the current end of the line being placed. It may not be equal to the cursor position due to collisions.
+		const VECTOR2I& CurrentEnd() const
+		{
+			if(m_head.GetCLine().PointCount() > 0)
+				return m_head.GetCLine().CPoint(-1);
+			else if(m_tail.GetCLine().PointCount() > 0)
+				return m_tail.GetCLine().CPoint(-1);
+			else
+				return m_p_start;
+		}
+
+
+		///> Returns all items in the world that have been affected by the routing operation. Used
+		///  to update data structures of the host application
+		void GetUpdatedItems( PNS_NODE::ItemVector& aRemoved,  PNS_NODE::ItemVector& aAdded);
+		
+		///> Toggles the current posture (straight/diagonal) of the trace head.
+		void FlipPosture();
+
+		///> Returns the most recent world state 
+		PNS_NODE *GetCurrentNode() const;
+
+	private:
+	
+		static const double m_shoveLengthThreshold = 1.7;
+
+		bool handleViaPlacement ( PNS_LINE& aHead );
+
+		bool checkObtusity(const SEG& a, const SEG& b) const;
+		bool handleSelfIntersections();
+		bool handlePullback();
+		bool mergeHead();
+		bool reduceTail(const VECTOR2I& aEnd); 
+		void fixHeadPosture();
+		bool optimizeTailHeadTransition();
+		
+		bool routeHead(const VECTOR2I& aP, PNS_LINE& aNewHead, bool aCwWalkaround = true);
+		void routeStep(const VECTOR2I& aP);
+
+		///> routing mode (walkaround, shove, etc.)
+		PNS_MODE m_mode;
+		///> follow mouse trail by attaching new segments to the head as the cursor moves
+		bool m_follow_mouse;
+		///> mouse smoothing active
+		bool m_smooth_mouse;
+		///> mouse smoothing step (in world units)
+		int m_smoothing_step;
+		///> current routing direction
+		DIRECTION_45 m_direction;
+		///> routing direction for new traces
+		DIRECTION_45 m_initial_direction;
+		///> routing "head": volatile part of the track from the previously 
+		///  analyzed point to the current routing destination
+		PNS_LINE m_head;
+		///> routing "tail": part of the track that has been already fixed due to collisions with obstacles
+		PNS_LINE m_tail;
+		///> current algorithm iteration
+		int m_iteration;
+		///> pointer to world to search colliding items
+		PNS_NODE *m_world;
+		///> current routing start point (end of tail, beginning of head)
+		VECTOR2I m_p_start;
+		///> The shove engine
+		PNS_SHOVE *m_shove;
+		///> Current world state
+		PNS_NODE *m_currentNode;
+		///> Are we placing a via?
+		bool m_placingVia;
+		///> current via diameter
+		int m_viaDiameter;
+		///> current via drill
+		int m_viaDrill;
+		///> walkaround algorithm iteration limit
+		int m_walkaroundIterationLimit;
+		///> smart pads optimizer enabled.
+		bool m_smartPads;
+};
+		
+#endif // __PNS_LINE_PLACER_H

pcbnew/router/pns_node.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <vector>
+#include <cassert>
+
+#include <math/vector2d.h>
+
+#include <geometry/seg.h>
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_index.h>
+
+#include "trace.h"
+#include "pns_item.h"
+#include "pns_line.h"
+#include "pns_node.h"
+#include "pns_via.h"
+#include "pns_solid.h"
+#include "pns_joint.h"
+#include "pns_index.h"
+
+using namespace std;
+
+using boost::unordered_set;
+using boost::unordered_map;
+
+static boost::unordered_set<PNS_NODE *> allocNodes;
+
+PNS_NODE::PNS_NODE()
+{
+	//printf("MakeNode [%p, total = %d]\n", this, allocNodes.size());
+	m_root = this;
+	m_parent = NULL;
+	m_maxClearance = 800000; // fixme: depends on how thick traces are.
+	m_index = new PNS_INDEX;
+	allocNodes.insert(this);
+}
+
+PNS_NODE::~PNS_NODE()
+{
+	if(!m_children.empty())
+	{
+		TRACEn(0, "attempting to free a node that has kids.\n");
+		assert(false);
+	}
+	
+	if(allocNodes.find(this) == allocNodes.end())
+	{
+		TRACEn(0, "attempting to free an already-free'd node.\n");
+		assert(false);
+	}
+
+	allocNodes.erase(this);
+
+	for(PNS_INDEX::ItemSet::iterator i = m_index->begin(); i != m_index->end(); ++i)
+		if( (*i) ->BelongsTo(this))
+			delete *i;
+
+	unlinkParent();
+	delete m_index;
+}
+
+
+int PNS_NODE::GetClearance(const PNS_ITEM *a, const PNS_ITEM *b) const
+{
+	int clearance = (* m_clearanceFunctor) (a, b);
+
+	if( a->OfKind (PNS_ITEM::SEGMENT) )
+		clearance += static_cast<const PNS_SEGMENT *>(a) -> GetWidth() / 2;
+
+	if( a->OfKind (PNS_ITEM::LINE) )
+		clearance += static_cast<const PNS_LINE *>(a) -> GetWidth() / 2;
+
+	if( b->OfKind (PNS_ITEM::SEGMENT) )
+		clearance += static_cast<const PNS_SEGMENT *>(b) -> GetWidth() / 2;
+
+	if( b->OfKind (PNS_ITEM::LINE) )
+		clearance += static_cast<const PNS_LINE *>(b) -> GetWidth() / 2;
+
+	return clearance;
+}
+
+PNS_NODE* PNS_NODE::Branch()
+{
+	PNS_NODE *child = new PNS_NODE;
+	m_children.push_back(child);
+
+	child->m_parent = this;
+	child->m_clearanceFunctor = m_clearanceFunctor;
+	child->m_root = isRoot() ? this : m_root;
+	
+	// immmediate offspring of the root branch needs not copy anything. For the rest,
+	// deep-copy joints, overridden item map and pointers to stored items.
+	if(!isRoot())
+	{
+	 	JointMap::iterator j;
+			
+		for(PNS_INDEX::ItemSet::iterator i = m_index->begin(); i != m_index->end(); ++i)
+			child->m_index->Add(*i);
+
+		child->m_joints = m_joints;		
+		child->m_override = m_override;
+	}
+	
+	TRACE(2, "%d items, %d joints, %d overrides", child->m_index->Size() % child->m_joints.size() % child->m_override.size());
+	
+	return child;
+}
+	
+void PNS_NODE::unlinkParent ( )
+{
+	if( isRoot() )
+		return;
+
+	for( vector<PNS_NODE *>::iterator i = m_parent->m_children.begin(); i != m_parent->m_children.end(); ++i)
+	{
+		if (*i == this)
+		{
+			m_parent->m_children.erase(i);
+			return;
+		}
+	}
+}
+	
+
+// function object that visits potential obstacles and performs the actual collision refining
+struct PNS_NODE::obstacleVisitor { 
+///> node we are searching in (either root or a branch)
+	PNS_NODE *m_node;
+///> node that overrides root entries
+	PNS_NODE *m_override;
+///> list of encountered obstacles
+	Obstacles& m_tab;
+///> the item we are looking for collisions with
+	const PNS_ITEM* m_item;
+///> acccepted kinds of colliding items (solids, vias, segments, etc...)
+	int m_kindMask;
+///> max number of hits
+	int m_limitCount;
+///> number of items found so far
+	int m_matchCount;
+
+	obstacleVisitor(	PNS_NODE::Obstacles& aTab, 
+						const PNS_ITEM* aItem,
+						int aKindMask )
+		: m_tab(aTab), 
+		  m_item(aItem), 
+		  m_kindMask(aKindMask),
+		  m_limitCount(-1),
+		  m_matchCount(0)
+		  { };
+
+	void SetCountLimit(int aLimit)
+	{
+		m_limitCount = aLimit;
+	}
+
+	void SetWorld(PNS_NODE *aNode, PNS_NODE *aOverride = NULL)
+	{
+		m_node = aNode;
+		m_override = aOverride;
+	}
+
+	bool operator()( PNS_ITEM *aItem )
+	{ 
+		if( !aItem->OfKind(m_kindMask)) 
+			return true;
+		// check if there is a more recent branch with a newer (possibily modified) version of this item.
+		if ( m_override && m_override -> overrides (aItem) )
+			return true;
+
+		int clearance = m_node->GetClearance(aItem, m_item);
+		if(!aItem->Collide(m_item, clearance))
+			return true;
+
+		PNS_OBSTACLE obs;
+		
+		obs.item = aItem;
+		m_tab.push_back(obs);
+
+		m_matchCount ++;
+		
+		if(m_limitCount > 0 && m_matchCount >= m_limitCount)
+			return false;
+		return true;
+	};
+}; 
+
+int PNS_NODE::QueryColliding( const PNS_ITEM* aItem, PNS_NODE::Obstacles& aObstacles, int aKindMask, int aLimitCount)
+{
+	obstacleVisitor visitor ( aObstacles, aItem, aKindMask );
+
+	assert(allocNodes.find(this) != allocNodes.end());
+
+	visitor.SetCountLimit(aLimitCount);
+	visitor.SetWorld( this, NULL );
+
+	// first, look for colliding items ourselves 
+	m_index->Query(aItem, m_maxClearance, visitor);
+
+	// if we haven't found enough items, look in the root branch as well.
+	if(!isRoot() && ( visitor.m_matchCount < aLimitCount || aLimitCount < 0) )
+	{
+		visitor.SetWorld ( m_root, this );
+		m_root->m_index->Query(aItem, m_maxClearance, visitor);
+	}
+
+		return aObstacles.size();
+}
+
+PNS_NODE::OptObstacle PNS_NODE::NearestObstacle( const PNS_LINE *aItem, int aKindMask)
+{
+	Obstacles obs_list;
+	bool found_isects = false;
+
+	const SHAPE_LINE_CHAIN &line = aItem->GetCLine();
+	
+	obs_list.reserve(100);
+
+	int n = 0;
+	for(int i = 0; i < line.SegmentCount(); i++)
+	{
+		const PNS_SEGMENT s ( *aItem, line.CSegment(i));
+		n += QueryColliding ( &s, obs_list, aKindMask );
+	}
+
+	if( aItem->EndsWithVia () )
+		n += QueryColliding ( &aItem->GetVia(), obs_list, aKindMask );
+
+	//if(! QueryColliding ( aItem, obs_list, aKindMask ))
+	if(!n)
+		return OptObstacle();
+
+	PNS_LINE& aLine = (PNS_LINE&) *aItem;
+	
+	PNS_OBSTACLE nearest;
+	nearest.item = NULL;
+	nearest.dist_first = INT_MAX;
+
+	BOOST_FOREACH(PNS_OBSTACLE obs, obs_list)
+	{
+		VECTOR2I ip_first, ip_last;
+		int dist_max = INT_MIN;
+
+		vector<SHAPE_LINE_CHAIN::Intersection> isect_list;
+	
+		int clearance = GetClearance(obs.item, &aLine);
+
+		SHAPE_LINE_CHAIN hull = obs.item->Hull ( clearance );
+
+		if(aLine.EndsWithVia())
+		{
+			int clearance = GetClearance(obs.item, &aLine.GetVia());
+
+			SHAPE_LINE_CHAIN viaHull = aLine.GetVia().Hull (clearance);
+
+			viaHull.Intersect(hull, isect_list);
+
+			BOOST_FOREACH(SHAPE_LINE_CHAIN::Intersection isect, isect_list)
+			{
+
+				int dist = aLine.GetCLine().Length() + (isect.p - aLine.GetVia().GetPos()).EuclideanNorm();
+
+				if(dist < nearest.dist_first)
+				{
+					found_isects = true;
+					nearest.dist_first = dist;
+					nearest.ip_first = isect.p;
+					nearest.item = obs.item;
+					nearest.hull = hull;
+				}
+
+				if(dist > dist_max)
+				{
+					dist_max = dist;
+					ip_last = isect.p;
+				}
+			}
+		}
+
+		isect_list.clear();
+
+		hull.Intersect(aLine.GetCLine(), isect_list);
+		
+		BOOST_FOREACH(SHAPE_LINE_CHAIN::Intersection isect, isect_list)
+		{
+
+			int dist = aLine.GetCLine().PathLength(isect.p);
+
+			if(dist < nearest.dist_first)
+			{
+				found_isects = true;
+				nearest.dist_first = dist;
+				nearest.ip_first = isect.p;
+				nearest.item = obs.item;
+				nearest.hull = hull;
+			}
+
+			if(dist > dist_max)
+			{
+				dist_max = dist;
+				ip_last = isect.p;
+			}
+			
+		}
+
+		nearest.ip_last = ip_last;
+		nearest.dist_last = dist_max;
+	}
+	
+	return found_isects ? nearest : OptObstacle();
+}
+
+PNS_NODE::OptObstacle PNS_NODE::CheckColliding( const PNS_ITEM *aItemA, int aKindMask )
+{
+	Obstacles obs;
+	obs.reserve(100);
+
+	if(aItemA->GetKind() == PNS_ITEM::LINE)
+	{
+		int n = 0;
+		const PNS_LINE *line = static_cast<const PNS_LINE *>(aItemA);
+		const SHAPE_LINE_CHAIN &l = line->GetCLine();
+
+		for(int i = 0; i < l.SegmentCount(); i++)
+		{
+			const PNS_SEGMENT s ( *line, l.CSegment(i));
+			n += QueryColliding ( &s, obs, aKindMask, 1 );
+			if(n)
+				return OptObstacle(obs[0]);
+		}
+		
+		if( line->EndsWithVia () )
+		{
+			n += QueryColliding ( &line->GetVia(), obs, aKindMask, 1 );
+			if(n)
+				return OptObstacle(obs[0]);
+		}
+
+	} else if (QueryColliding(aItemA, obs, aKindMask, 1) > 0)
+		return OptObstacle(obs[0]);
+	return OptObstacle();
+}
+
+bool PNS_NODE::CheckColliding( const PNS_ITEM *aItemA, const PNS_ITEM *aItemB, int aKindMask )
+{
+	Obstacles dummy;
+
+	assert(aItemB);
+	//	return QueryColliding(aItemA, dummy, aKindMask, 1) > 0;
+
+	return aItemA->Collide(aItemB, GetClearance(aItemA, aItemB));
+}
+
+struct hitVisitor { 
+	PNS_ITEMSET& m_items;
+	const VECTOR2I& m_point;
+	PNS_NODE *m_world;
+
+	hitVisitor(			PNS_ITEMSET& aTab, 
+						const VECTOR2I& aPoint,
+						PNS_NODE *aWorld )
+		: m_items(aTab), m_point(aPoint), m_world(aWorld) { };
+
+	bool operator()( PNS_ITEM *aItem ) { 
+		SHAPE_CIRCLE cp (m_point, 0);
+
+		int cl = 0;
+		if(aItem->GetKind() == PNS_ITEM::SEGMENT)
+			cl += static_cast<PNS_SEGMENT*>(aItem)->GetWidth() / 2;
+		
+		if(aItem->GetShape()->Collide(&cp, cl))
+			m_items.Add(aItem);
+		return true;
+	} 
+}; 
+
+const PNS_ITEMSET PNS_NODE::HitTest( const VECTOR2I& aPoint )
+{
+	PNS_ITEMSET items;
+	SHAPE_CIRCLE s (aPoint, 0); // fixme: we treat a point as an infinitely small circle - this is inefficient.
+	hitVisitor visitor ( items, aPoint, this );
+	
+	m_index->Query(&s, m_maxClearance, visitor);
+	
+	if( ! isRoot() ) // fixme: could be made cleaner
+	{
+		PNS_ITEMSET items_root;
+		hitVisitor visitor_root ( items_root, aPoint, m_root );
+		m_root->m_index->Query( &s, m_maxClearance, visitor_root );
+
+		BOOST_FOREACH(PNS_ITEM *item, items_root.Items())
+		{
+			if (!overrides(item))
+				items.Add(item);
+		}
+	}
+
+	return items;
+}
+
+void PNS_NODE::addSolid(PNS_SOLID *aSolid)
+{
+	linkJoint( aSolid->GetCenter(), aSolid->GetLayers(), aSolid->GetNet(), aSolid );
+	m_index->Add(aSolid);
+}
+
+void PNS_NODE::addVia(PNS_VIA *aVia)
+{
+	linkJoint( aVia->GetPos(), aVia->GetLayers(), aVia->GetNet(), aVia );
+	m_index->Add(aVia);
+}
+
+void PNS_NODE::addLine( PNS_LINE *aLine )
+{
+	const SHAPE_LINE_CHAIN& l = aLine->GetLine();
+
+	for(int i = 0; i < l.SegmentCount(); i++)
+	{
+		SEG s = l.CSegment(i);
+
+		if(s.a != s.b)
+		{
+			PNS_SEGMENT *pseg = new PNS_SEGMENT(*aLine, s);
+
+			pseg->SetOwner(this);
+
+			linkJoint( s.a, pseg->GetLayers(), aLine->GetNet(), pseg );
+			linkJoint( s.b, pseg->GetLayers(), aLine->GetNet(), pseg );
+
+			aLine->LinkSegment(pseg);
+
+			m_index->Add(pseg);
+		}
+	}
+}
+
+void PNS_NODE::addSegment( PNS_SEGMENT *aSeg )
+{
+	if(aSeg->GetSeg().a == aSeg->GetSeg().b)
+	{
+		TRACEn(0, "attempting to add a segment with same end coordinates, ignoring.")
+		return;
+	}
+	
+	aSeg->SetOwner (this);
+
+	linkJoint( aSeg->GetSeg().a, aSeg->GetLayers(), aSeg->GetNet(), aSeg );
+	linkJoint( aSeg->GetSeg().b, aSeg->GetLayers(), aSeg->GetNet(), aSeg );
+
+	m_index->Add(aSeg);
+}
+
+void PNS_NODE::Add(PNS_ITEM* aItem)
+{
+
+	aItem->SetOwner(this);
+
+	switch(aItem -> GetKind())
+	{
+		case PNS_ITEM::SOLID:
+			addSolid(static_cast<PNS_SOLID*>(aItem));
+			break;
+
+		case PNS_ITEM::SEGMENT:
+			addSegment(static_cast<PNS_SEGMENT*>(aItem));
+		 	break;
+
+		case PNS_ITEM::LINE:
+			addLine( static_cast<PNS_LINE*> (aItem));
+			break;
+
+		case PNS_ITEM::VIA:
+			addVia (static_cast<PNS_VIA*>(aItem));
+			break;
+
+		default:
+			assert (false);
+	}
+}	
+
+
+void PNS_NODE::doRemove ( PNS_ITEM *aItem )
+{
+	// case 1: removing an item that is stored in the root node from any branch: mark it as overridden, but do not remove
+	if( aItem->BelongsTo(m_root) && !isRoot() )
+		m_override.insert(aItem);
+
+	// case 2: the item belongs to this branch or a parent, non-root branch, or the root itself and we are the root: remove from the index
+	else if( !aItem->BelongsTo(m_root) || isRoot() )
+		m_index->Remove( aItem );
+
+	// the item belongs to this particular branch: un-reference it
+	if( aItem->BelongsTo( this ))
+		aItem->SetOwner(NULL);
+}
+
+void PNS_NODE::removeSegment (PNS_SEGMENT *aSeg )
+{
+	unlinkJoint(aSeg->GetSeg().a, aSeg->GetLayers(), aSeg->GetNet(), aSeg);
+	unlinkJoint(aSeg->GetSeg().b, aSeg->GetLayers(), aSeg->GetNet(), aSeg);
+
+	doRemove(aSeg);
+}
+
+void PNS_NODE::removeLine( PNS_LINE *aLine )
+{
+	vector<PNS_SEGMENT *> *segRefs = aLine->GetLinkedSegments();
+
+	if(!segRefs)
+		return;
+
+	assert ( aLine->GetOwner () );
+
+	BOOST_FOREACH(PNS_SEGMENT *seg, *segRefs)
+	{
+		removeSegment(seg);
+	}
+
+	aLine->SetOwner(NULL);
+}
+
+void PNS_NODE::removeVia ( PNS_VIA *aVia )
+{
+	unlinkJoint(aVia->GetPos(), aVia->GetLayers(), aVia->GetNet(), aVia);
+	
+	doRemove(aVia);
+}
+
+void PNS_NODE::Replace(PNS_ITEM *aOldItem, PNS_ITEM *aNewItem)
+{
+	Remove(aOldItem);
+	Add(aNewItem);
+}
+
+void PNS_NODE::Remove(PNS_ITEM *aItem)
+{
+	
+	switch(aItem -> GetKind())
+	{
+		case PNS_ITEM::SOLID:
+			assert(false);
+			break;
+		case PNS_ITEM::SEGMENT:
+		 	removeSegment(static_cast<PNS_SEGMENT*>(aItem));
+		 	break;
+		case PNS_ITEM::LINE:
+			removeLine(static_cast<PNS_LINE *>(aItem));
+			break;
+		case PNS_ITEM::VIA:
+			removeVia(static_cast<PNS_VIA *>(aItem));
+			break;
+		
+		default:
+			break;
+	}
+}
+
+void PNS_NODE::followLine(PNS_SEGMENT *current, bool scanDirection, int& pos, int limit, VECTOR2I *corners, PNS_SEGMENT **segments)
+{
+	bool prevReversed = false;
+	
+	for(;;)
+	{
+		const VECTOR2I p = (scanDirection ^ prevReversed) ? current->GetSeg().b : current->GetSeg().a;
+		const OptJoint jt = FindJoint(p, current->GetLayer(), current->GetNet());
+
+		assert (jt);
+		assert (pos > 0 && pos < limit);
+
+		corners [pos] = jt->GetPos();
+		segments [pos] = current;
+
+		pos += (scanDirection ? 1 : -1);
+		
+		if(!jt->IsLineCorner())
+			break;
+
+		current = jt->NextSegment( current );
+		prevReversed = (jt->GetPos() == (scanDirection ? current->GetSeg().b : current->GetSeg().a ));
+	}
+}
+
+PNS_LINE *PNS_NODE::AssembleLine(PNS_SEGMENT *aSeg, const OptJoint& a, const OptJoint& b)
+{
+	const int MaxVerts = 1024;
+	
+	VECTOR2I corners [ MaxVerts + 1 ]; 
+	PNS_SEGMENT *segs [ MaxVerts + 1 ];
+
+	PNS_LINE *pl = new PNS_LINE;
+	int i_start = MaxVerts/2, i_end = i_start + 1;
+
+	pl->SetWidth( aSeg->GetWidth() );
+	pl->SetLayers( aSeg->GetLayers() );
+	pl->SetNet ( aSeg->GetNet() );
+	pl->SetOwner(this);
+
+	//pl->LinkSegment(aSeg);
+	
+	followLine (aSeg, false, i_start, MaxVerts, corners, segs );
+	followLine (aSeg, true, i_end, MaxVerts, corners, segs );
+
+
+	int clip_start = -1, clip_end = -1;
+	for(int i = i_start+1 ; i < i_end ; i++)
+	{
+		const VECTOR2I &p = corners[i];
+		
+		if (a && (p == a->GetPos() || p == b->GetPos() ) )
+		{
+			clip_start = std::min(clip_start, i);
+			clip_end = std::max(clip_end, i);
+		}
+
+		pl->GetLine().Append(p);
+		if(segs[i-1] != segs[i])
+			pl->LinkSegment(segs[i]);
+	}
+
+	return pl;
+}
+
+void PNS_NODE::FindLineEnds (PNS_LINE *aLine, PNS_JOINT& a, PNS_JOINT& b )
+{
+	a = *FindJoint(aLine->GetCLine().CPoint(0),  aLine->GetLayers().Start(), aLine->GetNet());
+	b = *FindJoint(aLine->GetCLine().CPoint(-1), aLine->GetLayers().Start(), aLine->GetNet());	
+}
+
+
+int PNS_NODE::FindLinesBetweenJoints( PNS_JOINT& a, PNS_JOINT& b, vector<PNS_LINE *> &aLines )
+{
+	BOOST_FOREACH(PNS_ITEM *item, a.GetLinkList())
+	{
+		if(item->GetKind() == PNS_ITEM::SEGMENT)
+		{
+			PNS_SEGMENT *seg = static_cast<PNS_SEGMENT*>(item);
+			PNS_LINE *line = AssembleLine(seg);
+
+			PNS_JOINT j_start, j_end;
+			FindLineEnds( line, j_start, j_end );
+			if( (j_start == a && j_end == b )|| (j_end == a && j_start == b))
+				aLines.push_back(line);
+			else
+				delete line;
+		}
+	}
+	return 0;
+}
+
+const PNS_NODE::OptJoint PNS_NODE::FindJoint(const VECTOR2I &aPos, int aLayer, int aNet )
+{
+	PNS_JOINT::HashTag tag;
+
+	tag.net = aNet;
+	tag.pos = aPos;
+
+	JointMap::iterator f = m_joints.find(tag), end = m_joints.end();
+
+	if(f == end && !isRoot())
+	{
+		end = m_root->m_joints.end();
+		f = m_root->m_joints.find(tag); //m_root->FindJoint(aPos, aLayer, aNet);
+	} 
+
+	if(f == end)
+		return OptJoint();	
+
+	while (f != end)
+	{
+		if(f->second.GetLayers().Overlaps(aLayer))
+			return f->second;
+		++f;
+	}
+	return OptJoint();	
+}
+
+PNS_JOINT& PNS_NODE::touchJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet )
+{
+	PNS_JOINT::HashTag tag;
+	
+	tag.pos = aPos;
+	tag.net = aNet;
+
+	// try to find the joint in this node.
+	JointMap::iterator f = m_joints.find(tag);
+
+	pair<JointMap::iterator, JointMap::iterator> range;
+	
+	// not found and we are not root? find in the root and copy results here. 
+	if(f == m_joints.end() && !isRoot())
+	{
+		range = m_root->m_joints.equal_range(tag);
+		for( f = range.first; f != range.second; ++f)
+			m_joints.insert( *f );
+	} 
+
+	// now insert and combine overlapping joints
+	PNS_JOINT jt (aPos, aLayers, aNet);
+
+	bool merged;
+
+	do
+	{
+		merged = false;
+		range = m_joints.equal_range(tag);
+
+		if(range.first == m_joints.end())
+			break;
+
+		for(f = range.first; f != range.second; ++f)
+		{
+			if(aLayers.Overlaps (f->second.GetLayers()))
+			{
+				jt.Merge(f->second);
+				m_joints.erase(f);
+				merged = true;
+				break;
+			}
+		}
+	} while (merged);
+	
+	return m_joints.insert ( TagJointPair(tag, jt) )->second;
+}
+
+void PNS_JOINT::Dump() const
+{
+	printf("joint layers %d-%d, net %d, pos %s, links: %d\n", m_layers.Start(), m_layers.End(), m_tag.net, m_tag.pos.Format().c_str(), LinkCount() );
+}
+	
+
+void PNS_NODE::linkJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet, PNS_ITEM *aWhere )
+{
+	PNS_JOINT& jt = touchJoint( aPos, aLayers, aNet );
+	jt.Link(aWhere);
+}
+
+void PNS_NODE::unlinkJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet, PNS_ITEM *aWhere )
+{
+	// fixme: remove dangling joints
+	PNS_JOINT& jt = touchJoint( aPos, aLayers, aNet );
+	jt.Unlink(aWhere);
+}
+
+
+void PNS_NODE::Dump(bool aLong)
+{
+#if 0
+	boost::unordered_set<PNS_SEGMENT *> all_segs;
+	SHAPE_INDEX_LIST<PNS_ITEM *>::iterator i;
+
+	for(i = m_items.begin(); i != m_items.end() ; i++)
+	{
+		if((*i)->GetKind() == PNS_ITEM::SEGMENT)
+			all_segs.insert(static_cast<PNS_SEGMENT*>(*i));
+	}
+
+	if(!isRoot())
+		for(i = m_root->m_items.begin(); i != m_root->m_items.end() ; i++)
+		{
+			if((*i)->GetKind() == PNS_ITEM::SEGMENT && !overrides(*i))
+				all_segs.insert(static_cast<PNS_SEGMENT*>(*i));
+		}
+
+	
+	JointMap::iterator j;
+	if(aLong)
+	for(j=m_joints.begin(); j!=m_joints.end(); ++j)
+	{
+		printf("joint : %s, links : %d\n", j->second.GetPos().Format().c_str(), j->second.LinkCount());
+		PNS_JOINT::LinkedItems::const_iterator k;
+		for(k = j->second.GetLinkList().begin(); k != j->second.GetLinkList().end(); ++k)
+		{
+			const PNS_ITEM *item = *k;
+
+			switch(item->GetKind())
+			{
+				case PNS_ITEM::SEGMENT:
+				{
+					const PNS_SEGMENT *seg = static_cast<const PNS_SEGMENT *>(item);
+					printf(" -> seg %s %s\n", seg->GetSeg().a.Format().c_str(), seg->GetSeg().b.Format().c_str());
+					break;
+				}
+				default:
+					break;
+			}
+		}
+	}
+	
+	int lines_count = 0;
+	while(!all_segs.empty())
+	{
+		PNS_SEGMENT *s = *all_segs.begin();
+		PNS_LINE *l = AssembleLine(s);
+		
+		PNS_LINE::LinkedSegments* seg_refs = l->GetLinkedSegments(); 
+	
+		if(aLong)
+			printf("Line: %s, net %d ", l->GetLine().Format().c_str(), l->GetNet() );
+		
+		
+		for(vector<PNS_SEGMENT *>::iterator j = seg_refs->begin(); j != seg_refs->end(); ++j)
+		{
+			printf("%s ", (*j)->GetSeg().a.Format().c_str() );
+			if(j+1 == seg_refs->end())
+				printf("%s\n", (*j)->GetSeg().b.Format().c_str() );
+			all_segs.erase(*j);
+		}
+		lines_count++;
+	}
+		
+	printf("Local joints: %d, lines : %d \n", m_joints.size(), lines_count);
+#endif
+}
+
+void PNS_NODE::GetUpdatedItems( ItemVector& aRemoved,  ItemVector& aAdded)
+{
+	aRemoved.reserve(m_override.size());
+	aAdded.reserve(m_index->Size());
+
+	if(isRoot ())
+		return;
+
+	BOOST_FOREACH(PNS_ITEM *item, m_override)
+		aRemoved.push_back(item);
+	
+	for(PNS_INDEX::ItemSet::iterator i = m_index->begin(); i!=m_index->end(); ++i)
+		aAdded.push_back(*i);
+}
+
+void PNS_NODE::releaseChildren ()
+{
+	// copy the kids as the PNS_NODE destructor erases the item from the parent node.
+	vector<PNS_NODE *> kids = m_children;
+
+	BOOST_FOREACH(PNS_NODE *node, kids)
+	{
+		node->releaseChildren();
+		delete node;
+	}
+}
+
+void PNS_NODE::Commit( PNS_NODE *aNode )
+{
+
+	if(aNode->isRoot())
+		return;
+
+	BOOST_FOREACH( PNS_ITEM *item, aNode->m_override )
+		Remove(item);
+
+	for(PNS_INDEX::ItemSet::iterator i = aNode->m_index->begin(); i!= aNode ->m_index->end(); ++i)		
+		Add(*i);
+
+	releaseChildren();
+}
+
+void PNS_NODE::KillChildren()
+{
+	assert (isRoot());
+
+	releaseChildren();
+}
+
+
+
+void PNS_NODE::AllItemsInNet ( int aNet, std::list<PNS_ITEM *>& aItems)
+{
+	PNS_INDEX::NetItemsList* l_cur = m_index->GetItemsForNet ( aNet );
+
+	if(!l_cur)
+		return;
+
+	std::copy(aItems.begin(), l_cur->begin(), l_cur->end() );
+	if( !isRoot () )
+	{
+		PNS_INDEX::NetItemsList* l_root = m_root->m_index->GetItemsForNet ( aNet );
+
+		for(PNS_INDEX::NetItemsList::iterator i = l_root->begin(); i!= l_root->end(); ++i)	
+			if( !overrides( *i ))
+				aItems.push_back(*i);
+	}
+}

pcbnew/router/pns_node.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+#ifndef __PNS_NODE_H
+#define __PNS_NODE_H
+
+#include <vector>
+#include <list>
+
+#include <boost/unordered_set.hpp>
+#include <boost/unordered_map.hpp>
+#include <boost/optional.hpp>
+#include <boost/smart_ptr.hpp>
+
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_index.h>
+
+#include "pns_item.h"
+#include "pns_joint.h"
+#include "pns_itemset.h"
+
+class PNS_SEGMENT;
+class PNS_LINE;
+class PNS_SOLID;
+class PNS_VIA;
+class PNS_RATSNEST;
+class PNS_INDEX;
+
+using boost::shared_ptr;
+
+class PNS_CLEARANCE_FUNC {
+	public:
+		virtual int operator() ( const PNS_ITEM *a , const PNS_ITEM *b) = 0;
+};
+
+/**
+ * Struct PNS_OBSTACLE
+ *
+ * Holds an object colliding with another object, along with
+ * some useful data about the collision.
+ **/
+struct PNS_OBSTACLE 
+{
+	///> Item we search collisions with
+	PNS_ITEM *head;
+		
+	///> Item found to be colliding with head 
+	PNS_ITEM *item;
+
+	///> Hull of the colliding item
+	SHAPE_LINE_CHAIN hull;
+	
+	///> First and last intersection point between the head item and the hull of the 
+	//// colliding item
+	VECTOR2I ip_first, ip_last;
+	
+	///> ... and the distance thereof
+	int dist_first, dist_last;
+};
+
+/**
+ * Class PNS_NODE
+ *
+ * Keeps the router "world" - i.e. all the tracks, vias, solids in a hierarchical and indexed way. 
+ * Features:
+ * - spatial-indexed container for PCB item shapes
+ * - collision search (with clearance checking)
+ * - assembly of lines connecting joints, finding loops and unique paths
+ * - lightweight cloning/branching (for recursive optimization and shove springback)
+ **/
+
+class PNS_NODE {
+
+public:
+	
+	typedef boost::optional<PNS_OBSTACLE> OptObstacle;
+	typedef std::vector<PNS_ITEM *> ItemVector;
+	typedef std::vector<PNS_OBSTACLE> Obstacles;
+	typedef boost::optional<PNS_JOINT> OptJoint;
+
+	PNS_NODE ();
+	~PNS_NODE ();
+
+	///> Returns the expected clearance between items a and b.
+	int GetClearance(const PNS_ITEM *a, const PNS_ITEM *b) const;
+	
+	///> Returns the pre-set worst case clearance between any pair of items
+	int GetMaxClearance() const
+	{
+		return m_maxClearance;
+	}
+
+	void SetMaxClearance( int aClearance ) 
+	{
+		m_maxClearance = aClearance;
+	}
+
+	void SetClearanceFunctor (PNS_CLEARANCE_FUNC *aFunc)
+	{
+		m_clearanceFunctor = aFunc;
+	}
+
+	///> Finds items that collide with aItem and stores collision information in aObstacles.
+	int QueryColliding( const PNS_ITEM* aItem, Obstacles& aObstacles, int aKindMask = PNS_ITEM::ANY, int aLimitCount = -1);
+
+	///> Finds the nearest item that collides with aItem.
+	OptObstacle NearestObstacle( const PNS_LINE *aItem, int aKindMask = PNS_ITEM::ANY);
+
+	///> Checks if the item collides with anything else in the world, and returns it if so.
+	OptObstacle CheckColliding ( const PNS_ITEM *aItem, int aKindMask = PNS_ITEM::ANY);
+
+	///> Checks if two items collide [deprecated].
+	bool CheckColliding( const PNS_ITEM *aItemA, const PNS_ITEM *aItemB, int aKindMask = PNS_ITEM::ANY);
+
+	///> Hit detection
+	const PNS_ITEMSET HitTest( const VECTOR2I& aPoint );
+
+	void Add(PNS_ITEM *aItem);
+	void Remove(PNS_ITEM *aItem);
+	void Replace(PNS_ITEM *aOldItem, PNS_ITEM *aNewItem);
+
+	///> Creates a lightweight copy ("branch") of self. Note that if there are any branches
+	///  in use, their parents must NOT be deleted.
+	PNS_NODE *Branch();
+
+	///> Assembles a line connecting two non-trivial joints the segment aSeg belongs to.
+	PNS_LINE *AssembleLine(PNS_SEGMENT *aSeg, const OptJoint& a = OptJoint(), const OptJoint& b = OptJoint());
+	
+	///> Dumps the contents and joints structure	
+	void Dump(bool aLong = false);
+
+	///> Returns the number of joints
+	int JointCount() const
+	{
+		return m_joints.size();
+	}
+
+	///> Returns the lists of items removed and added in this branch, with respect
+	///> to the root.	
+	void GetUpdatedItems( ItemVector& aRemoved,  ItemVector& aAdded);
+
+	///> Copies the changes from a given branch (aNode) to the root. Called on 
+	///> a non-root branch will fail.
+	void Commit (PNS_NODE *aNode);
+
+	///> finds a joint at a given position, layer and nets
+	const OptJoint FindJoint(const VECTOR2I &aPos, int aLayer, int aNet);
+
+	///> finds all linest between a pair of joints. Used by the loop removal engine.
+	int FindLinesBetweenJoints( PNS_JOINT& a, PNS_JOINT& b, std::vector<PNS_LINE *> &aLines );
+
+	///> finds the joints corresponding to the ends of line aLine
+	void FindLineEnds (PNS_LINE *aLine, PNS_JOINT& a, PNS_JOINT& b );
+
+	///> finds all joints that have an (in)direct connection(s) (i.e. segments/vias) with the joint aJoint.
+	void FindConnectedJoints( const PNS_JOINT& aJoint, std::vector<PNS_JOINT *> &aConnectedJoints );
+
+	///> Destroys all child nodes. Applicable only to the root node.
+	void KillChildren();
+
+	void AllItemsInNet ( int aNet, std::list<PNS_ITEM *>& aItems);
+
+private:
+
+	struct obstacleVisitor;
+	typedef boost::unordered_multimap<PNS_JOINT::HashTag, PNS_JOINT> JointMap;	
+	typedef JointMap::value_type TagJointPair;
+
+	/// nodes are not copyable
+	PNS_NODE( const PNS_NODE& b);
+	PNS_NODE &operator=(const PNS_NODE& b);
+	
+	///> tries to find matching joint and creates a new one if not found
+	PNS_JOINT& touchJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet );
+	
+	///> touches a joint and links it to an item
+	void linkJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet, PNS_ITEM *aWhere );
+
+	///> unlinks an item from a joint
+	void unlinkJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet, PNS_ITEM *aWhere );
+	
+		///> helpers for adding/removing items
+
+	void addSolid( PNS_SOLID *aSeg );
+	void addSegment( PNS_SEGMENT *aSeg );
+	void addLine( PNS_LINE *aLine );
+	void addVia( PNS_VIA *aVia );
+	void removeSolid( PNS_SOLID *aSeg );
+	void removeLine( PNS_LINE *aLine );
+	void removeSegment (PNS_SEGMENT *aSeg );
+	void removeVia (PNS_VIA *aVia );
+
+	void doRemove( PNS_ITEM *aItem );
+	void unlinkParent ( );
+	void releaseChildren ();
+	
+	bool isRoot() const 
+	{
+		return m_parent == NULL;
+	}
+
+	///> checks if this branch contains an updated version of the item from the root branch.
+	bool overrides ( PNS_ITEM * aItem ) const 
+	{
+		return m_override.find(aItem) != m_override.end();
+	}
+
+	///> scans the joint map, forming a line starting from segment (current). 
+	void followLine(PNS_SEGMENT *current, bool scanDirection, int& pos, int limit, VECTOR2I *corners, PNS_SEGMENT **segments);
+
+	///> spatial index of all items
+	//SHAPE_INDEX_LIST<PNS_ITEM *> m_items;
+	
+	///> hash table with the joints, linking the items. Joints are hashed by their
+	///> position, layer set and net. 
+	JointMap m_joints;
+
+	///> node this node was branched from
+	PNS_NODE *m_parent;
+
+	///> root node of the whole hierarchy
+	PNS_NODE *m_root;
+	
+	///> list of nodes branched from this one
+	std::vector<PNS_NODE *> m_children;
+
+	///> hash of root's items that are more recent in this node
+	boost::unordered_set<PNS_ITEM *> m_override;
+
+	///> worst case item-item clearance 
+	int m_maxClearance;
+	
+	///> Clearance resolution functor
+	PNS_CLEARANCE_FUNC *m_clearanceFunctor;
+
+	///> Geometric/Net index of the items
+	PNS_INDEX *m_index;
+
+	///> list of currently processed obstacles.
+	Obstacles m_obstacleList;
+};
+
+#endif

pcbnew/router/pns_optimizer.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+#include <boost/foreach.hpp>
+
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_rect.h>
+
+#include "pns_line.h"
+#include "pns_node.h"
+#include "pns_optimizer.h"
+#include "pns_utils.h"
+
+
+using namespace std;
+
+/**
+
+Cost Estimator Methods
+
+**/
+
+int PNS_COST_ESTIMATOR::CornerCost( const SEG& a, const SEG& b) 
+{
+	DIRECTION_45 dir_a(a), dir_b(b);
+
+	switch(dir_a.Angle(dir_b))
+	{
+		case DIRECTION_45::ANG_OBTUSE:
+			return 1;
+		case DIRECTION_45::ANG_STRAIGHT:
+			return 0;
+		case DIRECTION_45::ANG_ACUTE:
+			return 50;
+		case DIRECTION_45::ANG_RIGHT:
+			return 30;
+		case DIRECTION_45::ANG_HALF_FULL:
+			return 60;
+		default:
+			return 100;
+	}
+}
+
+int PNS_COST_ESTIMATOR::CornerCost ( const SHAPE_LINE_CHAIN& aLine ) 
+{
+	int total = 0;
+	for (int i = 0; i < aLine.SegmentCount() - 1; ++i)
+		total += CornerCost(aLine.CSegment(i), aLine.CSegment(i + 1));
+	return total;
+}
+
+
+int PNS_COST_ESTIMATOR::CornerCost ( const PNS_LINE& aLine ) 
+{
+	return CornerCost(aLine.GetCLine());
+}
+
+void PNS_COST_ESTIMATOR::Add(PNS_LINE &aLine)
+{
+	m_lengthCost += aLine.GetCLine().Length();
+	m_cornerCost += CornerCost(aLine);
+}
+
+void PNS_COST_ESTIMATOR::Remove(PNS_LINE &aLine)
+{
+	m_lengthCost -= aLine.GetCLine().Length();
+	m_cornerCost -= CornerCost(aLine);
+}
+
+void PNS_COST_ESTIMATOR::Replace(PNS_LINE &aOldLine, PNS_LINE& aNewLine)
+{
+	m_lengthCost -= aOldLine.GetCLine().Length();
+	m_cornerCost -= CornerCost(aOldLine);
+	m_lengthCost += aNewLine.GetCLine().Length();
+	m_cornerCost += CornerCost(aNewLine);
+}
+
+
+bool PNS_COST_ESTIMATOR::IsBetter( PNS_COST_ESTIMATOR& aOther, double aLengthTollerance, double aCornerTollerance ) const
+{
+	if(aOther.m_cornerCost < m_cornerCost && aOther.m_lengthCost < m_lengthCost)
+		return true;
+	else if(aOther.m_cornerCost < m_cornerCost * aCornerTollerance && aOther.m_lengthCost < m_lengthCost * aLengthTollerance)
+		return true;
+
+	return false;
+}
+
+
+/**
+
+Optimizer
+
+**/
+
+
+PNS_OPTIMIZER::PNS_OPTIMIZER( PNS_NODE *aWorld ) :
+	m_world( aWorld ), m_collisionKindMask (PNS_ITEM::ANY), m_effortLevel(MERGE_SEGMENTS)
+	{
+	//	m_cache = new SHAPE_INDEX_LIST<PNS_ITEM*>();
+	}
+
+
+PNS_OPTIMIZER::~PNS_OPTIMIZER ( )
+{
+	//delete m_cache;
+}
+
+
+struct PNS_OPTIMIZER::CacheVisitor 
+{
+
+	CacheVisitor( const PNS_ITEM * aOurItem, PNS_NODE *aNode, int aMask ) :
+		m_ourItem(aOurItem), 
+		m_collidingItem(NULL),
+		m_node(aNode), 
+		m_mask(aMask) 
+		{};
+
+	bool operator() (PNS_ITEM *aOtherItem)
+	{
+		if(! m_mask & aOtherItem->GetKind())
+			return true;
+
+		int clearance = m_node->GetClearance(aOtherItem, m_ourItem); 
+
+		if(!aOtherItem->Collide(m_ourItem, clearance))
+			return true;
+
+		m_collidingItem = aOtherItem;
+		return false;
+	}
+
+	const PNS_ITEM *m_ourItem;
+	PNS_ITEM *m_collidingItem;
+	PNS_NODE *m_node;
+	int m_mask;
+};
+
+void PNS_OPTIMIZER::cacheAdd( PNS_ITEM *aItem, bool aIsStatic = false)
+{
+	if(m_cacheTags.find(aItem) != m_cacheTags.end())
+		return;
+
+	m_cache.Add(aItem);
+	m_cacheTags[aItem].hits = 1;
+	m_cacheTags[aItem].isStatic = aIsStatic;
+}
+
+void PNS_OPTIMIZER::removeCachedSegments (PNS_LINE *aLine, int aStartVertex, int aEndVertex)
+{
+	std::vector<PNS_SEGMENT *> *segs = aLine->GetLinkedSegments();
+
+	if(!segs)
+		return;
+
+	if(aEndVertex < 0)
+		aEndVertex += aLine->GetCLine().PointCount();
+
+	for(int i = aStartVertex; i < aEndVertex - 1; i++)
+	{
+		PNS_SEGMENT *s = (*segs)[i];
+		m_cacheTags.erase(s);
+		m_cache.Remove(s);
+	}//*cacheRemove( (*segs)[i] );
+}
+
+void PNS_OPTIMIZER::CacheRemove ( PNS_ITEM *aItem )
+{
+	if(aItem->GetKind() == PNS_ITEM::LINE)
+		removeCachedSegments(static_cast<PNS_LINE *> (aItem));
+}
+
+void PNS_OPTIMIZER::CacheStaticItem (PNS_ITEM *aItem)
+{
+	cacheAdd(aItem, true);
+}
+
+void PNS_OPTIMIZER::ClearCache( bool aStaticOnly  )
+{
+	if(!aStaticOnly)
+	{
+		m_cacheTags.clear();
+		m_cache.Clear();
+		return;
+	}
+	
+	for(CachedItemTags::iterator i = m_cacheTags.begin(); i!= m_cacheTags.end(); ++i)
+	{
+		if(i->second.isStatic)
+		{
+			m_cache.Remove(i->first);
+			m_cacheTags.erase(i->first);
+		}
+	}
+}
+
+bool PNS_OPTIMIZER::checkColliding ( PNS_ITEM *aItem, bool aUpdateCache )
+{
+	CacheVisitor v(aItem, m_world, m_collisionKindMask);
+
+	return m_world->CheckColliding(aItem);
+
+	// something is wrong with the cache, need to investigate.
+	m_cache.Query(aItem->GetShape(), m_world->GetMaxClearance(), v, false);
+
+	if(!v.m_collidingItem)
+	{
+		PNS_NODE::OptObstacle obs = m_world->CheckColliding(aItem);
+		
+		if(obs) {
+			
+			if(aUpdateCache)
+				cacheAdd(obs->item);
+			return true;
+		}
+	} else {
+		m_cacheTags[v.m_collidingItem].hits++;
+		return true;
+	}
+
+	return false;
+}
+
+bool PNS_OPTIMIZER::checkColliding( PNS_LINE *aLine, const SHAPE_LINE_CHAIN& aOptPath )
+{
+	PNS_LINE tmp(*aLine, aOptPath);
+	return checkColliding(&tmp);
+}
+
+bool PNS_OPTIMIZER::mergeObtuse (PNS_LINE *aLine)
+{
+	SHAPE_LINE_CHAIN &line = aLine->GetLine();
+
+	int step = line.PointCount() - 3;
+	int iter = 0;
+	int segs_pre = line.SegmentCount();
+
+	if(step < 0)
+		return false;
+
+	SHAPE_LINE_CHAIN current_path (line);
+
+	while(1)
+	{
+		iter++;
+		int n_segs = current_path.SegmentCount();
+		int max_step = n_segs - 2;
+		if(step > max_step)
+			step = max_step;
+
+		if(step < 2)
+		{
+			line = current_path;
+			return current_path.SegmentCount() < segs_pre;
+		}
+
+		bool found_anything = false;
+		int n = 0;
+
+		while (n < n_segs - step)
+		{
+			const SEG s1 = current_path.CSegment(n);
+			const SEG s2 = current_path.CSegment(n + step);
+			SEG s1opt, s2opt;
+
+			if (DIRECTION_45(s1).IsObtuse(DIRECTION_45(s2)))
+			{
+				VECTOR2I ip = *s1.IntersectLines(s2);
+
+				if(s1.Distance(ip) <= 1 || s2.Distance(ip) <= 1)
+				{
+					s1opt = SEG(s1.a, ip);
+					s2opt = SEG(ip, s2.b);
+				} else {
+					s1opt = SEG(s1.a, ip);
+					s2opt = SEG(ip, s2.b);
+				}
+						
+						
+				if (DIRECTION_45(s1opt).IsObtuse(DIRECTION_45(s2opt)))
+				{
+					SHAPE_LINE_CHAIN opt_path;
+					opt_path.Append(s1opt.a);
+					opt_path.Append(s1opt.b);
+					opt_path.Append(s2opt.b);
+
+					PNS_LINE opt_track (*aLine, opt_path);
+
+					if(!checkColliding(&opt_track))
+					{
+						current_path.Replace(s1.Index() + 1, s2.Index(), ip);
+						//removeCachedSegments(aLine, s1.Index(), s2.Index());
+						n_segs = current_path.SegmentCount();
+						found_anything = true;
+						break;
+					}
+				}
+			}
+			n++;
+		}
+
+		if(!found_anything)
+		{
+			if( step <= 2 )
+			{
+				line = current_path;
+				return line.SegmentCount() < segs_pre;
+			}
+			step --;
+		}
+	}
+	return  line.SegmentCount() < segs_pre;
+}
+
+
+bool PNS_OPTIMIZER::mergeFull(PNS_LINE *aLine)
+{
+	SHAPE_LINE_CHAIN &line = aLine->GetLine();
+	int step = line.SegmentCount() - 1;
+	
+	int segs_pre = line.SegmentCount();
+
+	line.Simplify();
+
+	if(step < 0)
+		return false;
+
+	SHAPE_LINE_CHAIN current_path (line);
+
+	while(1)
+	{
+		int n_segs = current_path.SegmentCount();
+		int max_step = n_segs - 2;
+	
+		if(step > max_step)
+			step = max_step;
+
+		if(step < 1)
+			break;
+		
+		bool found_anything = mergeStep(aLine, current_path, step);
+		
+		if(!found_anything)
+			step --;
+
+
+	}
+
+	aLine->SetShape(current_path);
+
+	return  current_path.SegmentCount() < segs_pre;
+}
+
+bool PNS_OPTIMIZER::Optimize ( PNS_LINE *aLine, PNS_LINE *aResult , int aStartVertex , int aEndVertex )
+{
+	if(!aResult)
+		aResult = aLine;
+	else
+		*aResult = *aLine;
+
+	m_keepPostures = false;	
+
+	bool rv = false;
+	if(m_effortLevel & MERGE_SEGMENTS)
+		rv |= mergeFull(aResult);
+	if(m_effortLevel & MERGE_OBTUSE)
+		rv |= mergeObtuse(aResult);
+	if(m_effortLevel & SMART_PADS)
+		rv |= runSmartPads(aResult);
+
+	return rv;
+}
+
+
+bool PNS_OPTIMIZER::mergeStep ( PNS_LINE *aLine, SHAPE_LINE_CHAIN& aCurrentPath, int step )
+{
+	int n = 0;
+	int n_segs = aCurrentPath.SegmentCount();
+	
+	int cost_orig = PNS_COST_ESTIMATOR::CornerCost(aCurrentPath);
+
+	
+	if(aLine->GetCLine().SegmentCount() < 4)
+		return false;
+
+	DIRECTION_45 orig_start (aLine->GetCLine().CSegment(0));
+	DIRECTION_45 orig_end (aLine->GetCLine().CSegment(-1));
+	
+	while (n < n_segs - step )
+	{
+		const SEG s1 = aCurrentPath.CSegment(n);
+		const SEG s2 = aCurrentPath.CSegment(n + step);
+
+		SHAPE_LINE_CHAIN path[2], *picked = NULL;
+		int cost[2];
+
+		for(int i = 0; i < 2; i++)
+		{
+			bool postureMatch = true;
+			SHAPE_LINE_CHAIN bypass = DIRECTION_45().BuildInitialTrace(s1.a, s2.b, i);
+			cost[i] = INT_MAX;
+				
+
+			if ( n == 0 && orig_start != DIRECTION_45( bypass.CSegment(0) ) )
+				postureMatch = false;
+			else if (n == n_segs-step && orig_end != DIRECTION_45( bypass.CSegment(-1)))
+				postureMatch = false;
+	
+			if((postureMatch || !m_keepPostures) && !checkColliding(aLine,  bypass))
+			{
+				path[i] = aCurrentPath;
+				path[i].Replace(s1.Index(), s2.Index(), bypass);
+				path[i].Simplify();
+				cost[i] = PNS_COST_ESTIMATOR::CornerCost(path[i]);
+			}
+		}
+
+		if(cost[0] < cost_orig && cost[0] < cost[1])
+			picked = &path[0];
+		else if (cost[1] < cost_orig)
+			picked = &path[1];
+
+		if(picked)
+		{
+			n_segs = aCurrentPath.SegmentCount();
+			aCurrentPath = *picked;
+			return true;
+		}
+		n++;
+	}
+
+	return false;
+}
+
+PNS_OPTIMIZER::BreakoutList PNS_OPTIMIZER::circleBreakouts( int aWidth, const SHAPE *aShape, bool aPermitDiagonal ) const
+{
+	BreakoutList breakouts;
+
+	for(int angle = 0; angle < 360; angle += 45)
+	{
+		const SHAPE_CIRCLE *cir = static_cast<const SHAPE_CIRCLE *> (aShape);
+		SHAPE_LINE_CHAIN l;
+		VECTOR2I p0 = cir->GetCenter ();
+		VECTOR2I v0 (cir->GetRadius() * M_SQRT2, 0);
+		l.Append ( p0 );
+		l.Append ( p0 + v0.Rotate ( angle * M_PI / 180.0 ) );
+		breakouts.push_back(l);
+	}
+	return breakouts;
+}
+
+
+PNS_OPTIMIZER::BreakoutList PNS_OPTIMIZER::rectBreakouts( int aWidth, const SHAPE *aShape, bool aPermitDiagonal ) const
+{
+	const SHAPE_RECT *rect = static_cast<const SHAPE_RECT *>(aShape);
+	VECTOR2I s = rect->GetSize(), c = rect->GetPosition() + VECTOR2I (s.x / 2, s.y / 2);
+	BreakoutList breakouts;
+
+	VECTOR2I d_offset;
+
+	d_offset.x = (s.x > s.y) ? (s.x - s.y) / 2 : 0;
+	d_offset.y = (s.x < s.y) ? (s.y - s.x) / 2 : 0;	
+
+	VECTOR2I d_vert = VECTOR2I ( 0, s.y / 2 + aWidth);
+	VECTOR2I d_horiz = VECTOR2I ( s.x / 2 + aWidth, 0);
+
+
+	breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c + d_horiz ) );
+	breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c - d_horiz ) );
+	breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c + d_vert ) );
+	breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c - d_vert ) );
+
+	if(aPermitDiagonal)
+	{
+		int l = aWidth + std::min(s.x, s.y) / 2;
+		VECTOR2I d_diag ;
+		
+		if(s.x >= s.y)
+		{
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c + d_offset, c + d_offset + VECTOR2I(l, l)));
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c + d_offset, c + d_offset - VECTOR2I(-l, l)));
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c - d_offset, c - d_offset + VECTOR2I(-l, l)));
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c - d_offset, c - d_offset - VECTOR2I(l, l)));
+		}  else {
+			// fixme: this could be done more efficiently
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c + d_offset, c + d_offset + VECTOR2I(l, l)));
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c - d_offset, c - d_offset - VECTOR2I(-l, l)));
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c + d_offset, c + d_offset + VECTOR2I(-l, l)));
+			breakouts.push_back ( SHAPE_LINE_CHAIN ( c, c - d_offset, c - d_offset - VECTOR2I(l, l)));
+					
+		}
+	}
+
+	return breakouts;
+}
+	
+	
+
+PNS_OPTIMIZER::BreakoutList PNS_OPTIMIZER::computeBreakouts( int aWidth, const PNS_ITEM *aItem, bool aPermitDiagonal ) const
+{
+	switch(aItem->GetKind())
+	{
+		case PNS_ITEM::VIA:
+		{
+			const PNS_VIA *via = static_cast<const PNS_VIA *> (aItem);
+				return circleBreakouts ( aWidth, via->GetShape(), aPermitDiagonal );
+		}
+
+		case PNS_ITEM::SOLID:
+		{
+			const SHAPE *shape = aItem->GetShape();
+			switch(shape->Type())
+			{
+				case SH_RECT:
+					return rectBreakouts (aWidth, shape, aPermitDiagonal);
+				case SH_CIRCLE:
+					return circleBreakouts (aWidth, shape, aPermitDiagonal);
+				default:
+					break;
+			}
+		}
+		default:
+			break;
+	}
+	return BreakoutList();
+}
+
+PNS_ITEM *PNS_OPTIMIZER::findPadOrVia ( int aLayer, int aNet, const VECTOR2I& aP) const
+{
+	PNS_NODE::OptJoint jt = m_world->FindJoint ( aP, aLayer, aNet );
+	if(!jt)
+		return NULL;
+
+	BOOST_FOREACH (PNS_ITEM *item, jt->GetLinkList() )
+	{
+		if(item->GetKind() == PNS_ITEM::VIA || item->GetKind() == PNS_ITEM::SOLID)
+			return item;
+	}
+	return NULL;
+}
+
+int PNS_OPTIMIZER::smartPadsSingle( PNS_LINE *aLine, PNS_ITEM *aPad, bool aEnd, int aEndVertex ) 
+{
+	int min_cost = INT_MAX;//PNS_COST_ESTIMATOR::CornerCost( line );
+	int min_len = INT_MAX;
+	DIRECTION_45 dir;
+			
+	const int ForbiddenAngles = DIRECTION_45::ANG_ACUTE | DIRECTION_45::ANG_RIGHT | DIRECTION_45::ANG_HALF_FULL | DIRECTION_45::ANG_UNDEFINED;
+
+	typedef pair<int, SHAPE_LINE_CHAIN> RtVariant;
+	vector<RtVariant> variants;
+
+	BreakoutList breakouts = computeBreakouts( aLine->GetWidth(), aPad, true );
+
+	SHAPE_LINE_CHAIN line = (aEnd ? aLine->GetCLine().Reverse() : aLine->GetCLine());
+
+	//bool startDiagonal = DIRECTION_45( line.CSegment(0) ).IsDiagonal();
+
+	int p_end = min (aEndVertex, min (3	, line.PointCount() - 1));
+
+	for (int p = 1; p <= p_end; p++)
+	{
+		BOOST_FOREACH(SHAPE_LINE_CHAIN& l, breakouts)
+		{
+			//PNSDisplayDebugLine (l, 0);
+			
+			
+			for(int diag = 0; diag < 2; diag++)
+			{
+				SHAPE_LINE_CHAIN v;
+				SHAPE_LINE_CHAIN connect = dir.BuildInitialTrace( l.CPoint(-1), line.CPoint(p), diag == 0);
+				
+				DIRECTION_45 dir_bkout ( l.CSegment(-1 ));
+				//DIRECTION_45 dir_head ( line.CSegment(p + 1));
+
+				int ang1 = dir_bkout.Angle ( DIRECTION_45(connect.CSegment(0) ));
+				int ang2 = 0;
+				//int ang2 = dir_head.Angle ( DIRECTION_45(connect.CSegment(-1) ));
+
+				if( (ang1 | ang2) & ForbiddenAngles )
+					continue;
+
+				if(l.Length() > line.Length())
+					continue;
+
+				v = l;
+
+				v.Append ( connect );
+
+				for(int i = p + 1; i < line.PointCount(); i++)
+					v.Append( line.CPoint(i) );
+				
+				PNS_LINE tmp(*aLine, v);
+				//tmp.GetLine().Simplify();
+				int cc = tmp.CountCorners(ForbiddenAngles);
+
+				if(cc == 0)
+				{
+					RtVariant vp;
+					vp.first = p;
+					vp.second = aEnd ? v.Reverse() : v;
+					vp.second.Simplify();
+					variants.push_back(vp);
+				}
+				
+			}
+ 			}
+	}
+
+	SHAPE_LINE_CHAIN l_best;
+	bool found = false;
+	int p_best = -1;
+
+	BOOST_FOREACH(RtVariant& vp, variants)
+	{
+		PNS_LINE tmp (*aLine, vp.second);
+		int cost = PNS_COST_ESTIMATOR::CornerCost(vp.second);
+		int len = vp.second.Length();
+
+		if(!checkColliding(&tmp))
+		{
+	
+
+/*			if(aEnd)
+				PNSDisplayDebugLine (l_best, 6);
+			else
+				PNSDisplayDebugLine (l_best, 5);*/
+
+			if(cost < min_cost || (cost == min_cost && len < min_len))
+			{
+				l_best = vp.second;
+				p_best = vp.first;
+				found = true;
+			
+			//if(cost == min_cost)
+				if(cost == min_cost)
+					min_len = std::min(len, min_len);
+				min_cost = std::min(cost, min_cost);
+			}
+			
+		}
+	}
+
+	if(found)
+	{
+//		printf("end: %d, p-best: %d, p-end: %d, p-total: %d\n", aEnd, p_best, p_end, l_best.PointCount());
+
+//		if(!aEnd) 
+//			PNSDisplayDebugLine (l_best, 5);
+//		else
+
+		aLine->SetShape(l_best);
+		return p_best;
+	}
+	return -1;
+}
+
+bool PNS_OPTIMIZER::runSmartPads(PNS_LINE *aLine)
+{
+	SHAPE_LINE_CHAIN& line = aLine->GetLine();
+
+	if (line.PointCount() < 3)
+		return false;
+
+	VECTOR2I p_start = line.CPoint(0), p_end = line.CPoint(-1);
+
+	PNS_ITEM *startPad = findPadOrVia( aLine->GetLayer(), aLine->GetNet(), p_start);
+	PNS_ITEM *endPad = findPadOrVia( aLine->GetLayer(), aLine->GetNet(), p_end);
+
+	int vtx = -1;
+
+	if(startPad)
+		vtx = smartPadsSingle(aLine, startPad, false, 3);
+	if(endPad)
+		smartPadsSingle(aLine, endPad, true, vtx < 0 ? line.PointCount() - 1 : line.PointCount() - 1 - vtx);
+
+	aLine->GetLine().Simplify();
+	return true;
+}
+
+bool PNS_OPTIMIZER::Optimize ( PNS_LINE *aLine, int aEffortLevel, PNS_NODE *aWorld )
+{
+	PNS_OPTIMIZER opt( aWorld ? aWorld : aLine->GetWorld() );
+	opt.SetEffortLevel (aEffortLevel);
+	opt.SetCollisionMask(-1);
+	return opt.Optimize(aLine);
+}

pcbnew/router/pns_optimizer.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+#ifndef __PNS_OPTIMIZER_H
+#define __PNS_OPTIMIZER_H
+
+#include <boost/unordered_map.hpp>
+#include <boost/shared_ptr.hpp>
+
+#include <geometry/shape_index_list.h>
+#include <geometry/shape_line_chain.h>
+
+class PNS_NODE;
+class PNS_LINE;
+class PNS_ROUTER;
+
+
+/**
+ * Class PNS_COST_ESTIMATOR
+ *
+ * Calculates the cost of a given line, taking corner angles and total length into account.
+ **/ 
+
+class PNS_COST_ESTIMATOR 
+{
+	public:
+		PNS_COST_ESTIMATOR():
+			m_lengthCost (0),
+			m_cornerCost (0)
+			{};
+
+		PNS_COST_ESTIMATOR(const PNS_COST_ESTIMATOR &b):
+			m_lengthCost (b.m_lengthCost),
+			m_cornerCost (b.m_cornerCost)
+			{};
+
+		~PNS_COST_ESTIMATOR() {};
+		
+		static int CornerCost ( const SEG& a, const SEG& b);
+		static int CornerCost ( const SHAPE_LINE_CHAIN& aLine );
+		static int CornerCost ( const PNS_LINE& aLine);
+
+		void Add(PNS_LINE &aLine);
+		void Remove (PNS_LINE &aLine);
+		void Replace(PNS_LINE &aOldLine, PNS_LINE& aNewLine);
+		
+		bool IsBetter( PNS_COST_ESTIMATOR& aOther, double aLengthTollerance, double aCornerTollerace ) const;
+
+		double GetLengthCost() const { return m_lengthCost; }
+		double GetCornerCost() const { return m_cornerCost; }
+
+	private:
+		double m_lengthCost;
+		int m_cornerCost;
+};
+
+/**
+ * Class PNS_OPTIMIZER
+ * 
+ * Performs various optimizations of the lines being routed, attempting to make the lines shorter
+ * and less cornery. There are 3 kinds of optimizations so far:
+ * - Merging obtuse segments (MERGE_OBTUSE): tries to join together as many 
+ *   obtuse segments as possible without causing collisions
+ * - Rerouting path between pair of line corners with a 2-segment "\__" line and iteratively repeating
+ *   the procedure as long as the total cost of the line keeps decreasing
+ * - "Smart Pads" - that is, rerouting pad/via exits to make them look nice (SMART_PADS). 
+ **/
+
+class PNS_OPTIMIZER 
+{
+	public:
+
+		enum OptimizationEffort {
+			MERGE_SEGMENTS = 0x1,
+			SMART_PADS = 0x2,
+			MERGE_OBTUSE = 0x4
+		};
+
+		PNS_OPTIMIZER( PNS_NODE *aWorld );
+		~PNS_OPTIMIZER();
+
+		///> a quick shortcut to optmize a line without creating and setting up an optimizer
+		static bool Optimize ( PNS_LINE *aLine, int aEffortLevel, PNS_NODE *aWorld = NULL );
+
+		bool Optimize ( PNS_LINE *aLine, PNS_LINE *aResult = NULL, int aStartVertex = 0, int aEndVertex = -1);
+
+		void SetWorld(PNS_NODE *aNode) { m_world = aNode; }
+		void CacheStaticItem (PNS_ITEM *aItem);
+		void CacheRemove( PNS_ITEM *aItem );
+		void ClearCache( bool aStaticOnly = false );
+
+		void SetCollisionMask ( int aMask )
+		{
+			m_collisionKindMask = aMask;
+		}
+
+		void SetEffortLevel ( int aEffort )
+		{
+			m_effortLevel = aEffort;
+		}
+	
+	private:
+
+		static const int MaxCachedItems = 256;
+
+		typedef std::vector<SHAPE_LINE_CHAIN> BreakoutList;	
+
+		struct CacheVisitor;
+	
+		struct CachedItem
+		{
+			int hits;
+			bool isStatic;
+		};
+
+		bool mergeObtuse (PNS_LINE *aLine);
+		bool mergeFull (PNS_LINE *aLine);
+		bool removeUglyCorners (PNS_LINE *aLine);
+		bool runSmartPads(PNS_LINE *aLine);
+		bool mergeStep ( PNS_LINE *aLine, SHAPE_LINE_CHAIN& aCurrentLine, int step );
+
+		bool checkColliding( PNS_ITEM *aItem, bool aUpdateCache = true );
+		bool checkColliding( PNS_LINE *aLine, const SHAPE_LINE_CHAIN& aOptPath );
+
+
+		void cacheAdd( PNS_ITEM *aItem, bool aIsStatic );
+		void removeCachedSegments (PNS_LINE *aLine, int aStartVertex = 0, int aEndVertex = -1);
+
+		BreakoutList circleBreakouts( int aWidth, const SHAPE *aShape, bool aPermitDiagonal ) const;
+		BreakoutList rectBreakouts( int aWidth, const SHAPE *aShape, bool aPermitDiagonal ) const;
+		BreakoutList ovalBreakouts( int aWidth, const SHAPE *aShape, bool aPermitDiagonal ) const;
+		BreakoutList computeBreakouts( int aWidth, const PNS_ITEM *aItem, bool aPermitDiagonal ) const;
+
+		int smartPadsSingle( PNS_LINE *aLine, PNS_ITEM *aPad, bool aEnd, int aEndVertex );
+
+		PNS_ITEM *findPadOrVia ( int aLayer, int aNet, const VECTOR2I& aP) const;
+
+		SHAPE_INDEX_LIST<PNS_ITEM *> m_cache;
+
+		typedef boost::unordered_map<PNS_ITEM*, CachedItem> CachedItemTags;
+		CachedItemTags m_cacheTags;
+		PNS_NODE *m_world;
+		int m_collisionKindMask;
+		int m_effortLevel;
+		bool m_keepPostures;
+};
+
+#endif

pcbnew/router/pns_router.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+#include <cstdio>
+#include <vector>
+
+#include <boost/foreach.hpp>
+
+#include <view/view.h>
+#include <view/view_item.h>
+#include <view/view_group.h>
+#include <gal/graphics_abstraction_layer.h>
+
+#include <pcb_painter.h>
+
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_rect.h>
+#include <geometry/shape_circle.h>
+ 
+#include "trace.h"
+#include "pns_node.h"
+#include "pns_line_placer.h"
+#include "pns_line.h"
+#include "pns_solid.h"
+#include "pns_utils.h"
+#include "pns_router.h"
+
+#include <router/router_preview_item.h>
+
+#include <class_board.h>
+#include <class_board_item.h>
+#include <class_pad.h>
+#include <class_track.h>
+#include <layers_id_colors_and_visibility.h> 
+
+using namespace std;
+
+// an ugly singleton for drawing debug items within the router context. To be fixed sometime in the future.
+static PNS_ROUTER *theRouter;
+
+class PCBNEW_CLEARANCE_FUNC : public PNS_CLEARANCE_FUNC 
+{
+	public:
+		PCBNEW_CLEARANCE_FUNC( BOARD *aBoard )
+		{
+			m_clearanceCache.resize(aBoard->GetNetCount());
+
+			for(unsigned int i = 0; i < aBoard->GetNetCount(); i++)
+			{
+				NETINFO_ITEM *ni = aBoard->FindNet(i);
+				wxString netClassName = ni->GetClassName();
+				NETCLASS *nc = aBoard->m_NetClasses.Find(netClassName);
+				int clearance = nc->GetClearance();
+				m_clearanceCache[i] = clearance;
+				TRACE(1, "Add net %d netclass %s clearance %d", i % netClassName.mb_str() % clearance);
+			}
+
+			m_defaultClearance = 254000;//aBoard->m_NetClasses.Find ("Default clearance")->GetClearance();
+		}
+
+		int operator() (const PNS_ITEM *a , const PNS_ITEM *b)
+		{
+			int net_a = a->GetNet();
+			int cl_a = (net_a >= 0 ? m_clearanceCache[net_a] : m_defaultClearance);
+			int net_b = b->GetNet();
+			int cl_b = (net_b >= 0 ? m_clearanceCache[net_b] : m_defaultClearance);
+			return std::max(cl_a, cl_b);
+		}
+	
+	private:
+
+		vector<int> m_clearanceCache;
+		int m_defaultClearance;
+};
+
+PNS_ITEM *PNS_ROUTER::syncPad( D_PAD *aPad )
+{
+	PNS_LAYERSET layers;
+
+	switch(aPad->GetAttribute())
+	{
+		case PAD_STANDARD: 
+			layers = PNS_LAYERSET(0, 15);
+			break;
+		case PAD_SMD:
+		case PAD_CONN:
+		{
+			LAYER_MSK lmsk = aPad->GetLayerMask();
+			int i;
+
+			for(i = FIRST_COPPER_LAYER; i <= LAST_COPPER_LAYER; i++)
+				if( lmsk & (1<<i))
+				{
+					layers = PNS_LAYERSET( i );
+					break;
+				}
+			break;
+		}
+		default:
+			TRACE(0, "unsupported pad type 0x%x", aPad->GetAttribute());
+			return NULL;
+	}
+
+	PNS_SOLID *solid = new PNS_SOLID;
+
+	solid->SetLayers(layers);
+	solid->SetNet( aPad->GetNet() );
+	wxPoint wx_c = aPad->GetPosition();
+    wxSize wx_sz = aPad->GetSize();
+
+    VECTOR2I c(wx_c.x, wx_c.y);
+	VECTOR2I sz(wx_sz.x, wx_sz.y);
+
+	solid->SetCenter( c );
+    
+
+	double orient = aPad->GetOrientation() / 10.0;
+
+	if(orient == 90.0 || orient == 270.0)
+		sz = VECTOR2I(sz.y, sz.x);
+	else if (orient != 0.0 && orient != 180.0)
+	{
+			TRACEn(0, "non-orthogonal pad rotations not supported yet");
+			delete solid;
+			return NULL;
+	}
+
+	switch(aPad->GetShape())
+	{
+		case PAD_CIRCLE:
+			solid->SetShape ( new SHAPE_CIRCLE ( c, sz.x / 2) );
+			break;
+        case PAD_OVAL:
+        	if(sz.x == sz.y)
+				solid->SetShape ( new SHAPE_CIRCLE ( c, sz.x / 2) );
+			else
+				solid->SetShape ( new SHAPE_RECT ( c - sz / 2, sz.x, sz.y) );
+			break;
+
+	    case PAD_RECT:
+	    	solid->SetShape ( new SHAPE_RECT ( c - sz / 2, sz.x, sz.y) );	
+	    	break;
+
+	    default:
+	 		TRACEn(0, "unsupported pad shape");
+			delete solid;
+			return NULL;   
+	}
+
+
+	solid->SetParent(aPad);
+	return solid;	
+}
+	
+PNS_ITEM *PNS_ROUTER::syncTrack( TRACK *aTrack )
+{
+
+	PNS_SEGMENT *s  = new PNS_SEGMENT( SEG (aTrack->GetStart(), aTrack->GetEnd() ), aTrack->GetNet() );
+	
+	s->SetWidth( aTrack->GetWidth() );
+	s->SetLayers (PNS_LAYERSET(aTrack->GetLayer()));
+	s->SetParent(aTrack);
+	return s;
+}
+
+	
+PNS_ITEM *PNS_ROUTER::syncVia( SEGVIA *aVia )
+{
+	PNS_VIA *v = new PNS_VIA(
+			aVia->GetPosition(),
+			PNS_LAYERSET(0, 15),
+			aVia->GetWidth(),
+			aVia->GetNet());
+
+	v->SetParent(aVia);
+	return v;
+}
+
+void PNS_ROUTER::SetBoard( BOARD *aBoard )
+{
+	m_board = aBoard;
+	TRACE(1, "m_board = %p\n", m_board);
+}
+	
+int PNS_ROUTER::NextCopperLayer( bool aUp )
+{
+	LAYER_MSK mask = m_board->GetEnabledLayers() & m_board->GetVisibleLayers();
+	LAYER_NUM l = m_currentLayer;
+
+	do {
+		l += (aUp ? 1 : -1);
+		if(l > LAST_COPPER_LAYER)
+			l = FIRST_COPPER_LAYER;
+		
+		if(l < FIRST_COPPER_LAYER)
+			l = LAST_COPPER_LAYER;
+
+		if(mask & GetLayerMask(l))
+			return l;
+	
+	} while (l != m_currentLayer);
+
+	return l;
+}
+
+void PNS_ROUTER::SyncWorld()
+{
+	vector<D_PAD *> pads;
+
+	if(!m_board)
+	{
+		TRACEn(0,"No board attached, aborting sync.");
+		return;
+	}
+		
+	ClearWorld();
+	
+
+	m_clearanceFunc = new PCBNEW_CLEARANCE_FUNC(m_board);
+	m_world = new PNS_NODE();
+	m_world->SetClearanceFunctor ( m_clearanceFunc );
+	m_world->SetMaxClearance ( 1000000 ); //m_board->GetBiggestClearanceValue());
+	pads = m_board->GetPads();
+
+	BOOST_FOREACH( D_PAD *pad, pads )
+	{
+		PNS_ITEM *solid = syncPad(pad);
+		if(solid)
+			m_world->Add(solid);
+	}
+
+	for(TRACK *t = m_board->m_Track; t; t = t->Next())
+	{
+		KICAD_T type = t->Type();
+		PNS_ITEM *item = NULL;
+		if(type == PCB_TRACE_T)
+			item = syncTrack ( t );
+		else if( type == PCB_VIA_T )
+			item = syncVia (static_cast <SEGVIA *>(t));
+
+		if(item)
+			m_world->Add(item);
+	}
+
+	m_placer = new PNS_LINE_PLACER ( m_world );
+}
+
+PNS_ROUTER::PNS_ROUTER()
+{
+	theRouter = this;
+
+	m_clearanceFunc = NULL;
+
+	m_currentLayer = 1;
+	m_placingVia = false;
+	m_currentNet = -1;
+	m_state = IDLE;
+	m_world = NULL;
+	m_placer = NULL;
+	m_previewItems = NULL;
+	m_start_diagonal = false;
+	m_board = NULL;
+
+	TRACE(1, "m_board = %p\n", m_board);
+}
+
+
+void PNS_ROUTER::SetView(KiGfx::VIEW *aView)
+{
+	if(m_previewItems)
+	{
+		m_previewItems->FreeItems();
+		delete m_previewItems;
+	}
+
+	m_view = aView;
+	m_previewItems = new KiGfx::VIEW_GROUP(m_view);
+	m_previewItems->SetLayer(ITEM_GAL_LAYER( GP_OVERLAY ));
+	m_view -> Add (m_previewItems);
+	m_previewItems->ViewSetVisible(true);
+
+}
+
+PNS_ROUTER *PNS_ROUTER::GetInstance()
+{
+	return theRouter;
+}
+
+PNS_ROUTER::~PNS_ROUTER()
+{
+	ClearWorld();
+	theRouter = NULL;
+}
+
+void PNS_ROUTER::ClearWorld()
+{
+	if(m_world)
+		delete m_world;
+	if(m_clearanceFunc)
+		delete m_clearanceFunc;
+	if(m_placer)
+		delete m_placer;
+
+	m_clearanceFunc = NULL;
+	m_world = NULL;	
+	m_placer = NULL;
+}
+
+void PNS_ROUTER::SetCurrentWidth (int w )
+{
+	// fixme: change width while routing
+	m_currentWidth = w;
+}
+
+bool PNS_ROUTER::RoutingInProgress() const
+{
+	return m_state != IDLE;
+}
+
+
+const PNS_ITEMSET PNS_ROUTER::QueryHoverItems(const VECTOR2I&aP)
+{
+	if(m_state == IDLE)
+		return m_world->HitTest( aP );
+	else
+		return m_placer->GetCurrentNode() -> HitTest(aP);
+}
+
+
+const VECTOR2I PNS_ROUTER::SnapToItem( PNS_ITEM *item, VECTOR2I aP, bool& aSplitsSegment )
+{
+ 	VECTOR2I anchor;
+
+ 	if(!item)
+ 	{
+ 		aSplitsSegment = false;
+ 		return aP;
+ 	}
+
+	switch(item->GetKind())
+	{
+		case PNS_ITEM::SOLID:
+			anchor = static_cast<PNS_SOLID *>(item)->GetCenter();
+			aSplitsSegment = false;
+			break;
+		case PNS_ITEM::VIA:
+			anchor =  static_cast<PNS_VIA *>(item)->GetPos();
+			aSplitsSegment = false;
+			break;
+		case PNS_ITEM::SEGMENT:			
+		{
+			PNS_SEGMENT *seg = static_cast<PNS_SEGMENT *>(item);
+			const SEG& s = seg->GetSeg();
+			int w = seg->GetWidth();
+
+			aSplitsSegment = false;
+
+			if ((aP - s.a).EuclideanNorm() < w / 2)
+				anchor = s.a;
+			else if ((aP - s.b).EuclideanNorm() < w / 2)
+				anchor = s.b;
+			else {
+				anchor = s.NearestPoint(aP);
+				aSplitsSegment = true;
+			}
+			break;
+		}
+		default:
+			break;
+	}
+	return anchor;
+}
+
+
+void PNS_ROUTER::StartRouting(const VECTOR2I& aP, PNS_ITEM *aStartItem)
+{
+	VECTOR2I p;
+	
+	static int unknowNetIdx = 0;//-10000;
+	
+	m_placingVia = false;
+	m_startsOnVia = false;
+	m_currentNet = -1;
+
+		bool splitSeg = false;
+
+	p = SnapToItem( aStartItem, aP, splitSeg );
+
+	if(!aStartItem || aStartItem->GetNet() < 0)
+		m_currentNet = unknowNetIdx--;
+	else
+		m_currentNet = aStartItem->GetNet();
+
+	m_currentStart = p;
+	m_originalStart = p;
+	m_currentEnd = p;
+
+	m_placer->SetInitialDirection(m_start_diagonal ? DIRECTION_45(DIRECTION_45::NE) : DIRECTION_45(DIRECTION_45::N));
+	m_placer->StartPlacement(m_originalStart, m_currentNet, m_currentWidth, m_currentLayer);
+	m_state = ROUTE_TRACK;
+
+	if(splitSeg)
+		splitAdjacentSegments(m_placer->GetCurrentNode(), aStartItem, p);
+
+
+}
+
+const VECTOR2I PNS_ROUTER::GetCurrentEnd( ) const
+{
+	return m_currentEnd;
+}
+
+void PNS_ROUTER::EraseView()
+{
+	BOOST_FOREACH(BOARD_ITEM *item, m_hiddenItems)
+	{
+		item->ViewSetVisible(true);
+	}
+	
+	if(m_previewItems)
+		m_previewItems->FreeItems();
+	m_previewItems->ViewUpdate( KiGfx::VIEW_ITEM::GEOMETRY );
+}
+
+void PNS_ROUTER::DisplayItem(const PNS_ITEM* aItem, bool aIsHead)
+{
+
+	ROUTER_PREVIEW_ITEM * pitem = new ROUTER_PREVIEW_ITEM (aItem, m_previewItems);
+	
+	m_previewItems->Add (pitem);
+	if(aIsHead)
+		pitem->MarkAsHead();
+
+	pitem->ViewSetVisible(true);
+	m_previewItems->ViewUpdate( KiGfx::VIEW_ITEM::GEOMETRY | KiGfx::VIEW_ITEM::APPEARANCE );
+}
+
+void PNS_ROUTER::DisplayDebugLine ( const SHAPE_LINE_CHAIN &aLine, int aType, int aWidth)
+{
+	ROUTER_PREVIEW_ITEM * pitem = new ROUTER_PREVIEW_ITEM (NULL, m_previewItems);
+	
+	pitem->DebugLine (aLine, aWidth, aType );
+	m_previewItems->Add (pitem);
+	pitem->ViewSetVisible(true);
+	m_previewItems->ViewUpdate( KiGfx::VIEW_ITEM::GEOMETRY | KiGfx::VIEW_ITEM::APPEARANCE );
+}
+
+void PNS_ROUTER::DisplayDebugBox ( const BOX2I& aBox, int aType , int aWidth )
+{
+
+}
+	
+
+void PNS_ROUTER::Move(const VECTOR2I& aP, PNS_ITEM *endItem)
+{
+	PNS_NODE::ItemVector removed, added;
+	VECTOR2I p = aP;
+
+	if(m_state == IDLE)
+		return;
+
+	if(m_state == START_ROUTING)
+	{
+		
+	}
+
+	EraseView();
+
+	m_currentEnd = p;
+	m_placer->Route(p);
+
+	PNS_LINE current = m_placer->GetTrace();
+
+	DisplayItem (&current, true); 
+
+	if(current.EndsWithVia())
+		DisplayItem( &current.GetVia(), true );
+
+	m_placer->GetCurrentNode()->GetUpdatedItems(removed, added);
+
+	BOOST_FOREACH(PNS_ITEM *item, added)
+	{
+		DisplayItem(item); 
+	}
+
+	BOOST_FOREACH(PNS_ITEM *item, removed)
+	{
+		BOARD_ITEM *parent = item->GetParent();
+
+		if(parent)
+		{
+			if(parent->ViewIsVisible())
+				m_hiddenItems.insert(parent);
+
+			parent->ViewSetVisible(false);
+			parent->ViewUpdate (KiGfx::VIEW_ITEM::APPEARANCE);
+		}
+	}	
+}
+
+void PNS_ROUTER::splitAdjacentSegments(PNS_NODE *aNode, PNS_ITEM *aSeg, const VECTOR2I& aP )
+{
+	if(aSeg && aSeg->OfKind( PNS_ITEM::SEGMENT ))
+	{
+		PNS_NODE::OptJoint jt = aNode->FindJoint ( aP, aSeg->GetLayers().Start(), aSeg->GetNet());
+
+		if(jt && jt->LinkCount() >= 1)
+			return;
+		
+		PNS_SEGMENT *s_old = static_cast<PNS_SEGMENT*>(aSeg);
+		PNS_SEGMENT *s_new [2];
+
+		s_new[0] = s_old->Clone();
+		s_new[1] = s_old->Clone();
+
+		s_new[0]->SetEnds (s_old->GetSeg().a, aP);
+		s_new[1]->SetEnds (aP, s_old->GetSeg().b);
+
+
+		aNode->Remove( s_old );
+		aNode->Add( s_new [0] );
+		aNode->Add( s_new [1] );
+	}
+}
+
+void PNS_ROUTER::commitRouting( PNS_NODE *aNode )
+{
+	PNS_NODE::ItemVector removed, added;
+
+	aNode->GetUpdatedItems(removed, added);
+
+	for(unsigned int i = 0; i < removed.size(); i++)
+	{
+		BOARD_ITEM *parent = removed[i]->GetParent();
+
+		if(parent)
+		{
+			m_view->Remove(parent);
+			m_board->Remove(parent);
+		}
+	}
+
+	BOOST_FOREACH(PNS_ITEM *item, added)
+	{
+		BOARD_ITEM *newBI = NULL;
+		switch(item->GetKind())
+		{
+			case PNS_ITEM::SEGMENT:
+			{
+				PNS_SEGMENT *seg = static_cast<PNS_SEGMENT*>(item);
+				TRACK *track = new TRACK(m_board);
+				const SEG& s = seg->GetSeg();
+
+				track->SetStart( wxPoint(s.a.x, s.a.y));
+				track->SetEnd( wxPoint(s.b.x, s.b.y ));
+				track->SetWidth(seg->GetWidth());
+				track->SetLayer(seg->GetLayers().Start());
+				track->SetNet(seg->GetNet());
+				newBI = track;
+				break;
+			}
+		
+			case PNS_ITEM::VIA:
+			{
+				SEGVIA *via_board = new SEGVIA(m_board);
+				PNS_VIA *via = static_cast<PNS_VIA *>(item);
+				via_board->SetPosition ( wxPoint(via->GetPos().x, via->GetPos().y ));
+				via_board->SetWidth ( via->GetDiameter() );
+				via_board->SetNet ( via->GetNet() );
+				newBI = via_board;
+				break;				
+			}
+
+			default:
+				break;
+		}
+
+		if(newBI)
+		{
+			item->SetParent(newBI);
+			newBI->ClearFlags();
+			m_view->Add(newBI);
+			m_board->Add(newBI);
+			newBI->ViewUpdate( KiGfx::VIEW_ITEM::GEOMETRY );
+		}
+	}
+	
+	m_world->Commit( aNode );
+}
+
+PNS_VIA *PNS_ROUTER::checkLoneVia ( PNS_JOINT* aJoint ) const
+{
+	PNS_VIA *theVia = NULL;
+	PNS_LAYERSET l;
+
+	BOOST_FOREACH(PNS_ITEM *item, aJoint->GetLinkList())
+	{
+		if(item->GetKind() == PNS_ITEM::VIA)
+			theVia = static_cast<PNS_VIA *>(item);
+
+	
+		l.Merge (item->GetLayers());
+	}
+
+	if(l.Start() == l.End())
+		return theVia;
+	return NULL;
+}
+
+PNS_NODE *PNS_ROUTER::removeLoops ( PNS_NODE *aNode, PNS_SEGMENT *aLatestSeg )
+{
+	PNS_LINE *ourLine = aNode->AssembleLine(aLatestSeg);
+	PNS_NODE *cleaned = aNode->Branch();
+	PNS_JOINT a, b;
+	vector<PNS_LINE *> lines;
+	
+
+	cleaned->FindLineEnds (ourLine, a, b);
+	cleaned->FindLinesBetweenJoints( a, b, lines);
+	
+	BOOST_FOREACH(PNS_LINE *line, lines)
+	{
+		if(! (line->ContainsSegment (aLatestSeg) ) )
+		{
+			cleaned->Remove(line);
+		}
+	}
+
+	return cleaned;
+}
+
+
+
+bool PNS_ROUTER::FixRoute(const VECTOR2I& aP, PNS_ITEM *aEndItem)
+	{
+	bool real_end = false;
+	
+	PNS_LINE pl = m_placer->GetTrace();
+	const SHAPE_LINE_CHAIN& l = pl.GetCLine();
+
+	if(!l.SegmentCount())
+		return true;
+
+	VECTOR2I p_pre_last = l.CPoint(-1);
+	const VECTOR2I p_last = l.CPoint(-1);
+		DIRECTION_45 d_last (l.CSegment(-1));
+
+	if(l.PointCount() > 2)
+		p_pre_last = l.CPoint(-2);
+
+	if(aEndItem && m_currentNet >= 0 && m_currentNet == aEndItem->GetNet())
+		real_end = true;
+	
+	int last = (real_end || m_placingVia) ? l.SegmentCount() : max(1, l.SegmentCount() - 1);
+
+	PNS_NODE *latest = m_placer->GetCurrentNode();
+
+	if(real_end)
+		splitAdjacentSegments(latest, aEndItem, aP);
+	
+	PNS_SEGMENT *lastSeg = NULL;
+	for (int i = 0; i < last; i++)
+	{	
+		const SEG& s = pl.GetCLine().CSegment(i);
+		PNS_SEGMENT *seg = new PNS_SEGMENT( s, m_currentNet );
+		seg->SetWidth(pl.GetWidth());
+		seg->SetLayer(m_currentLayer);
+		latest->Add(seg);
+		lastSeg = seg;
+	}
+
+	if( pl.EndsWithVia() )
+		latest->Add(pl.GetVia().Clone());
+
+	if(real_end)
+		latest = removeLoops( latest, lastSeg );
+	
+	commitRouting(latest);
+
+	EraseView();
+	
+	if(real_end)
+	{
+		m_state = IDLE;
+		//m_world->KillChildren();
+	} else {
+	
+		m_state = ROUTE_TRACK;
+		m_placer->SetInitialDirection(d_last);
+		m_currentStart = m_placingVia ? p_last : p_pre_last;
+	
+		if(m_placingVia)
+			m_currentLayer = NextCopperLayer(true);
+
+		m_placer->StartPlacement(m_currentStart, m_currentNet, m_currentWidth, m_currentLayer);
+
+		m_startsOnVia = m_placingVia;
+		m_placingVia = false;
+
+	}
+	
+
+	return real_end;
+}
+
+void PNS_ROUTER::StopRouting()
+{
+	if(!RoutingInProgress())
+		return;
+
+	//highlightCurrent(false);
+	
+	EraseView();
+	
+	m_state = IDLE;
+	m_world->KillChildren();
+}
+
+void PNS_ROUTER::FlipPosture()
+{
+	if(m_placer->GetTail().GetCLine().SegmentCount() == 0)
+	{
+		m_start_diagonal = !m_start_diagonal; 
+		m_placer->SetInitialDirection(m_start_diagonal ? DIRECTION_45(DIRECTION_45::NE) : DIRECTION_45(DIRECTION_45::N));
+	} else
+		m_placer->FlipPosture();
+	
+	Move(m_currentEnd, NULL);
+}
+
+void PNS_ROUTER::SwitchLayer(int layer)
+{
+	switch(m_state)
+	{
+		case IDLE:
+			m_currentLayer = layer;
+			break;
+		case ROUTE_TRACK:
+			if(m_startsOnVia)
+			{
+				m_currentLayer = layer;
+				m_placer->StartPlacement(m_currentStart, m_currentNet, m_currentWidth, m_currentLayer);
+			}
+		default:
+			break;
+	}
+}
+
+void PNS_ROUTER::ToggleViaPlacement ()
+{
+	if(m_state == ROUTE_TRACK)
+		{
+			m_placingVia = !m_placingVia;
+			m_placer->AddVia(m_placingVia, m_currentViaDiameter, m_currentViaDrill);
+		}
+}		
+

pcbnew/router/pns_router.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+#ifndef __PNS_ROUTER_H
+#define __PNS_ROUTER_H
+
+#include <list>
+
+#include <boost/optional.hpp>
+#include <boost/unordered_set.hpp>
+
+#include <geometry/shape_line_chain.h>
+
+#include "pns_routing_settings.h"
+#include "pns_item.h"
+#include "pns_itemset.h"
+
+class BOARD;
+class BOARD_ITEM;
+class D_PAD;
+class TRACK;
+class SEGVIA;
+class PNS_NODE;
+class PNS_LINE_PLACER;
+class PNS_ITEM;
+class PNS_LINE;
+class PNS_SOLID;
+class PNS_SEGMENT;
+class PNS_JOINT;
+class PNS_VIA;
+class PNS_CLEARANCE_FUNC;
+class VIEW_GROUP;
+
+namespace KiGfx {
+	class VIEW;
+	class VIEW_GROUP;
+};
+
+
+/** 
+ * Class PNS_ROUTER
+ * 
+ * Main router class. 
+ */
+
+class PNS_ROUTER {
+
+private:	
+	enum RouterState {
+		IDLE,
+		START_ROUTING,
+		ROUTE_TRACK,
+		FINISH_TRACK
+	};
+
+public:
+
+	PNS_ROUTER ();
+	~PNS_ROUTER ();
+
+	static PNS_ROUTER *GetInstance();
+
+	void ClearWorld();
+	void SetBoard( BOARD *aBoard );
+	void SyncWorld();
+
+	void SetView(KiGfx::VIEW *aView);
+
+	bool RoutingInProgress() const;
+	void StartRouting(const VECTOR2I& aP, PNS_ITEM *aItem);
+	void Move(const VECTOR2I& aP, PNS_ITEM *aItem);
+	bool FixRoute(const VECTOR2I& aP, PNS_ITEM *aItem);
+
+	void StopRouting();
+
+	const VECTOR2I GetCurrentEnd() const;
+
+	int GetClearance(const PNS_ITEM* a, const PNS_ITEM *b ) const;
+
+	PNS_NODE* GetWorld() const
+	{
+		return m_world;
+	}
+
+	void FlipPosture();
+	
+	void DisplayItem ( const PNS_ITEM *aItem, bool aIsHead = false );
+	void DisplayDebugLine ( const SHAPE_LINE_CHAIN &aLine, int aType = 0, int aWidth = 0);
+	void DisplayDebugBox ( const BOX2I& aBox, int aType = 0, int aWidth = 0);
+	
+	void EraseView ( );
+	void SwitchLayer (int layer );
+	int GetCurrentLayer() const { return m_currentLayer; }
+	void ToggleViaPlacement ();
+
+	void SetCurrentWidth(int w);
+	void SetCurrentViaDiameter(int d) { m_currentViaDiameter = d;}
+	void SetCurrentViaDrill(int d) { m_currentViaDrill = d;}
+	int GetCurrentWidth() const { return m_currentWidth; }
+	int GetCurrentViaDiameter() const { return m_currentViaDiameter; }
+	int GetCurrentViaDrill() const { return m_currentViaDrill; }
+	int GetCurrentNet() const { return m_currentNet; }
+
+	PNS_CLEARANCE_FUNC *GetClearanceFunc() const
+	{
+		return m_clearanceFunc;
+	}
+
+	bool IsPlacingVia() const
+	{
+		return m_placingVia;
+	}
+
+
+	int NextCopperLayer( bool aUp );
+
+	//typedef boost::optional<hoverItem> optHoverItem;
+
+	const PNS_ITEMSET QueryHoverItems(const VECTOR2I& aP);
+	const VECTOR2I SnapToItem( PNS_ITEM *item, VECTOR2I aP, bool& aSplitsSegment );
+
+
+private:
+
+
+
+	void clearViewFlags();
+	
+	//optHoverItem queryHoverItemEx(const VECTOR2I& aP);
+	
+	PNS_ITEM *pickSingleItem ( PNS_ITEMSET &aItems ) const; //std::vector<PNS_ITEM*> aItems) const;
+	void splitAdjacentSegments(PNS_NODE *aNode, PNS_ITEM *aSeg, const VECTOR2I& aP ); //optHoverItem& aItem);
+	void commitRouting ( PNS_NODE *aNode );
+	PNS_NODE *removeLoops ( PNS_NODE *aNode, PNS_SEGMENT *aLatestSeg );
+	PNS_NODE *removeLoops ( PNS_NODE *aNode, PNS_LINE *aNewLine );
+	PNS_VIA *checkLoneVia ( PNS_JOINT* aJoint ) const;
+
+	PNS_ITEM *syncPad( D_PAD *aPad );
+	PNS_ITEM *syncTrack( TRACK *aTrack );
+	PNS_ITEM *syncVia( SEGVIA *aVia );
+
+	void commitPad( PNS_SOLID *aPad );
+	void commitSegment( PNS_SEGMENT *aTrack );
+	void commitVia( PNS_VIA *aVia );
+
+	void highlightCurrent( bool enabled );
+
+
+	int m_currentLayer;
+	int m_currentNet;
+	int m_currentWidth;
+	int m_currentViaDiameter;
+	int m_currentViaDrill;
+
+	bool m_start_diagonal;
+
+	RouterState m_state;
+
+	BOARD *m_board;
+	PNS_NODE *m_world;
+	PNS_LINE_PLACER *m_placer;
+
+	KiGfx::VIEW *m_view;
+	KiGfx::VIEW_GROUP *m_previewItems;
+
+	VECTOR2I m_currentEnd;
+	VECTOR2I m_currentStart;
+	VECTOR2I m_originalStart;
+	bool m_placingVia;
+	bool m_startsOnVia;
+
+//	optHoverItem m_startItem, m_endItem;
+	
+	PNS_ROUTING_SETTINGS m_settings;
+	PNS_CLEARANCE_FUNC *m_clearanceFunc;
+
+	boost::unordered_set<BOARD_ITEM *> m_hiddenItems;
+
+};
+
+#endif
\ No newline at end of file

pcbnew/router/pns_routing_settings.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+ 
+#ifndef __PNS_ROUTER_SETTINGS
+#define __PNS_ROUTER_SETTINGS
+
+///> Routing modes
+enum PNS_MODE {
+	RM_Ignore = 0, ///> Ignore collisions
+	RM_Shove,      ///> Only shove
+	RM_Walkaround, ///> Only walkaround
+	RM_Smart       ///> Guess what's better
+};
+
+class PNS_ROUTING_SETTINGS 
+{
+	public:
+		PNS_MODE m_routingMode;
+
+		bool m_removeLoops;
+		bool m_smartPads;
+		bool m_suggestEnding;
+		bool m_shoveOnRequest;
+		bool m_changePostures;
+		bool m_followMouse;
+
+		int m_lineWidth;
+		int m_viaDiameter;
+		int m_viaDrill;
+		int m_preferredLayer;
+		int m_walkaroundIterationLimit;
+		int m_shoveIterationLimit;
+};
+
+#endif
+

pcbnew/router/pns_segment.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+ 
+#ifndef __PNS_SEGMENT_H
+#define __PNS_SEGMENT_H
+
+#include <math/vector2d.h>
+
+#include <geometry/seg.h>
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+
+#include "pns_item.h"
+#include "pns_line.h"
+
+class PNS_NODE;
+
+class PNS_SEGMENT : public PNS_ITEM {
+public:
+	PNS_SEGMENT ():
+		PNS_ITEM(SEGMENT)
+		{};
+
+	PNS_SEGMENT (const SEG& aSeg, int aNet):
+		PNS_ITEM(SEGMENT)
+		{
+			m_net = aNet;
+			m_shape.Clear();
+			m_shape.Append(aSeg.a);
+			m_shape.Append(aSeg.b);
+		};
+	
+	PNS_SEGMENT (const PNS_LINE &aParentLine, const SEG& aSeg):
+		PNS_ITEM(SEGMENT)
+		{
+			m_net = aParentLine.GetNet();
+			m_layers = aParentLine.GetLayers();
+			m_width = aParentLine.GetWidth();
+			m_shape.Clear();
+			m_shape.Append(aSeg.a);
+			m_shape.Append(aSeg.b);
+		};
+	
+
+	PNS_SEGMENT *Clone() const;
+	
+	const SHAPE* GetShape() const { 
+		return static_cast<const SHAPE *>(&m_shape); 
+	}
+
+	void SetLayer (int aLayer)
+	{
+		SetLayers (PNS_LAYERSET ( aLayer ));
+	}
+
+	int GetLayer() const 
+	{
+		return GetLayers().Start();
+	}
+
+	const SHAPE_LINE_CHAIN& GetCLine() const
+	{
+		return m_shape;
+	}
+
+	void SetWidth( int aWidth )
+	{
+		m_width = aWidth;
+	}
+
+	int GetWidth() const {
+		return m_width;
+	}
+	
+	const SEG GetSeg() const {
+		assert(m_shape.PointCount() >= 1);
+		if(m_shape.PointCount() == 1)
+			return SEG(m_shape.CPoint(0), m_shape.CPoint(0));
+		return SEG(m_shape.CPoint(0), m_shape.CPoint(1));
+	}
+
+	void SetEnds ( const VECTOR2I& a, const VECTOR2I& b)
+	{
+		m_shape.Clear();
+		m_shape.Append(a);
+		m_shape.Append(b);
+	}
+
+	void SwapEnds()
+	{
+		m_shape = m_shape.Reverse();
+	}
+
+	const SHAPE_LINE_CHAIN Hull(int aClearance, int aWalkaroundThickness) const;
+
+private:
+
+	SHAPE_LINE_CHAIN m_shape;
+	int m_width;
+};
+
+#endif

pcbnew/router/pns_shove.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <deque>
+#include <cassert>
+
+#include <wx/timer.h>
+
+#include "trace.h"
+
+#include "pns_line.h"
+#include "pns_node.h"
+#include "pns_walkaround.h"
+#include "pns_shove.h"
+#include "pns_optimizer.h"
+#include "pns_via.h"
+#include "pns_utils.h"
+
+#include <profile.h>
+
+using namespace std;
+
+PNS_SHOVE::PNS_SHOVE( PNS_NODE *aWorld ) 
+{
+	m_root = aWorld;
+	m_iterLimit = 100;
+};
+
+PNS_SHOVE::~PNS_SHOVE()
+{
+}
+
+struct range {
+	range()
+	{
+		min_v = max_v = -1;
+	}
+
+	void add ( int x )
+	{
+		if(min_v < 0) min_v = x;
+		if(max_v < 0) max_v = x;
+
+		if(x < min_v)
+			min_v = x;
+		else if (x > max_v) 
+			max_v = x;
+	}
+
+	int start()
+	{
+		return min_v;
+	}
+
+	int end()
+	{
+		return max_v;
+	}
+
+	int min_v, max_v;
+};
+
+// fixme: this is damn f***ing inefficient. And fails much too often due to broken direction finding algorithm.
+bool PNS_SHOVE::tryShove(PNS_NODE *aNode, PNS_LINE *aHead, PNS_LINE *aObstacle, PNS_SEGMENT& aObstacleSeg, PNS_LINE *aResult, bool aInvertWinding )
+{
+	const SHAPE_LINE_CHAIN &head = aHead->GetCLine();
+	bool cw = false;
+	int i;
+
+	if(aHead->EndsWithVia() && !aHead->GetLayers().Overlaps(aObstacle->GetLayers()))
+	{
+		int clearance = aNode->GetClearance(aHead, aObstacle);
+		SHAPE_LINE_CHAIN hull = aHead->GetVia().Hull( clearance - aObstacle->GetWidth() / 2 );
+
+		//SHAPE_LINE_CHAIN path_pre, path_walk_cw, path_walk_ccw, path_post;
+
+		SHAPE_LINE_CHAIN path_cw, path_ccw, *path;
+
+		aObstacle->NewWalkaround(hull, path_cw, true);
+		aObstacle->NewWalkaround(hull, path_ccw, false);
+
+		path = path_ccw.Length() < path_cw.Length() ? &path_ccw : &path_cw;
+		aResult->SetShape(*path);
+
+		//PNSDisplayDebugLine (*path, 5);
+
+		if(!aResult->Is45Degree())
+		{
+			//printf("polyset non-45\npoly %s\nendpolyset\n", aResult->GetCLine().Format().c_str());
+		}
+		/*... special case for vias? */
+
+		return !aNode->CheckColliding(aResult, aHead);
+	}
+
+	int ns = head.SegmentCount();
+	if(aHead->EndsWithVia())
+		ns ++;
+
+	for(i = 0; i < head.SegmentCount(); i++)
+	{
+		const PNS_SEGMENT hs (*aHead, head.CSegment(i));
+
+
+
+		if(aNode->CheckColliding(&hs, aObstacle))
+		{
+			VECTOR2I v1 = hs.GetSeg().b - hs.GetSeg().a;
+			VECTOR2I v2 = aObstacleSeg.GetSeg().b - aObstacleSeg.GetSeg().a;
+				
+			VECTOR2I::extended_type det = v1.Cross(v2);
+
+			if(det > 0)
+				cw = true;
+			else
+				cw = false;
+			
+			break;
+		}
+	}
+
+	if(aInvertWinding)
+	{ 
+		if(cw)
+			cw = false;
+		else
+			cw = true;
+	}
+
+	PNS_LINE shoved (*aObstacle);
+
+	int clearance = aNode->GetClearance(aHead, aObstacle);
+
+	range r;
+
+	for(i = 0; i < ns; i++)
+	{
+		SHAPE_LINE_CHAIN hull;
+		
+		if(i < head.SegmentCount())
+		{
+			const PNS_SEGMENT hs (*aHead, head.CSegment(i));
+			hull = hs.Hull( clearance, 0 );
+		} else 
+			hull = aHead->GetVia().Hull( clearance - aObstacle->GetWidth() / 2);
+		
+		SHAPE_LINE_CHAIN path_pre, path_walk, path_post, tmp;
+		SHAPE_LINE_CHAIN path_pre2, path_walk2, path_post2;
+
+		//shoved.NewWalkaround(hull, path_pre, path_walk, path_post, cw);
+		shoved.NewWalkaround(hull, path_pre, path_walk, path_post, cw);
+
+		/*if(path_pre != path_pre2 || path_post != path_post2 || path_walk != path_walk2 )
+		{
+			TRACE(5, "polyset orig\npoly %s\npoly %s\npoly %s\nendpolyset\n", path_pre.Format().c_str() % path_walk.Format().c_str() % path_post.Format().c_str());
+			TRACE(5, "polyset err\npoly %s\npoly %s\npoly %s\nendpolyset\n", path_pre2.Format().c_str() % path_walk2.Format().c_str() % path_post2.Format().c_str());
+		}*/
+
+		tmp = shoved.GetCLine();
+		if(path_walk.SegmentCount())
+			r.add(i);
+
+		path_pre.Append(path_walk);
+		path_pre.Append(path_post);
+		path_pre.Simplify();
+		shoved.SetShape(path_pre);
+//		shoved.SetAffectedRange ( start, end );
+		*aResult = shoved;		
+		
+		if(!aResult->Is45Degree())
+		{
+			//TRACE(5, "polyset non-45\npoly %s\npoly %s\npoly %s\nendpolyset\n", tmp.Format().c_str() % hull.Format().c_str() % aResult->GetCLine().Format().c_str());
+		}
+		
+	}
+
+	TRACE(2, "CW %d affectedRange %d-%d [total %d]", (cw?1:0) % r.start() % r.end() % ns);
+
+	return !aNode->CheckColliding(aResult, aHead);
+}
+
+PNS_SHOVE::ShoveStatus PNS_SHOVE::shoveSingleLine(PNS_NODE *aNode, PNS_LINE *aCurrent, PNS_LINE *aObstacle, PNS_SEGMENT& aObstacleSeg, PNS_LINE *aResult )
+{
+	bool rv = tryShove(aNode, aCurrent, aObstacle, aObstacleSeg, aResult, false);
+
+	if( !rv )
+		rv = tryShove(aNode, aCurrent, aObstacle, aObstacleSeg, aResult, true);
+
+	if( !rv )
+	{
+		TRACEn(2, "Shove failed" );
+		return SH_INCOMPLETE;
+	}
+
+	aResult->GetLine().Simplify();
+
+	const SHAPE_LINE_CHAIN& sh_shoved = aResult->GetCLine();
+	const SHAPE_LINE_CHAIN& sh_orig = aObstacle->GetCLine();
+
+	if(sh_shoved.SegmentCount() > 1 && sh_shoved.CPoint(0) == sh_orig.CPoint(0) && sh_shoved.CPoint(-1) == sh_orig.CPoint(-1) )
+		return SH_OK;
+	else if (!sh_shoved.SegmentCount())
+		return SH_NULL;
+	else
+		return SH_INCOMPLETE;
+}
+
+bool PNS_SHOVE::reduceSpringback( PNS_LINE *aHead )
+{
+	bool rv = false;
+	
+	while(!m_nodeStack.empty())
+	{
+		SpringbackTag st_stack = m_nodeStack.back();
+		bool tail_ok = true;
+		
+		if(!st_stack.node->CheckColliding(aHead) && tail_ok)
+		{
+			rv = true;
+			delete st_stack.node;
+			m_nodeStack.pop_back();
+		} else
+			break;
+	}
+
+	return rv;
+}
+
+bool PNS_SHOVE::pushSpringback( PNS_NODE *aNode, PNS_LINE *aHead, const PNS_COST_ESTIMATOR& aCost )
+{
+	BOX2I headBB = aHead->GetCLine().BBox();
+	SpringbackTag st;
+	
+	st.node = aNode;
+	st.cost = aCost;
+	st.length = std::max(headBB.GetWidth(), headBB.GetHeight());;
+	m_nodeStack.push_back(st);
+	return true;
+}
+
+const PNS_COST_ESTIMATOR PNS_SHOVE::TotalCost() const
+{
+	if(m_nodeStack.empty())
+		return PNS_COST_ESTIMATOR();
+	else 
+		return m_nodeStack.back().cost;
+}
+
+PNS_SHOVE::ShoveStatus PNS_SHOVE::ShoveLines(PNS_LINE* aCurrentHead)
+{
+	stack <PNS_LINE *> lineStack;
+	PNS_NODE *node, *parent;
+	PNS_VIA *headVia = NULL;
+	bool fail = false;
+	int iter = 0;
+
+	PNS_LINE *head = aCurrentHead->Clone(); 
+
+	reduceSpringback(aCurrentHead);
+
+	parent = m_nodeStack.empty() ? m_root : m_nodeStack.back().node;
+	node = parent->Branch();
+
+	lineStack.push(head);
+
+	//node->Add(tail);
+	node->Add(head);
+
+	if(head->EndsWithVia())
+	{
+		headVia = head->GetVia().Clone();
+		node->Add( headVia );
+	}
+
+	PNS_OPTIMIZER optimizer (node);
+
+	optimizer.SetEffortLevel (PNS_OPTIMIZER::MERGE_SEGMENTS | PNS_OPTIMIZER::SMART_PADS);
+	optimizer.SetCollisionMask( -1 );
+	PNS_NODE::OptObstacle nearest;
+
+	optimizer.CacheStaticItem(head);
+	if(headVia)
+		optimizer.CacheStaticItem(headVia);
+
+	TRACE(1, "ShoveStart [root: %d jts, node: %d jts]", m_root->JointCount() % node->JointCount());
+	
+	//PNS_ITEM *lastWalkSolid = NULL;
+  	prof_counter totalRealTime;
+
+
+  	wxLongLong  t_start   = wxGetLocalTimeMillis();
+
+	while(!lineStack.empty())
+	{
+
+		wxLongLong  t_cur   = wxGetLocalTimeMillis();
+
+		if ((t_cur - t_start).ToLong() > ShoveTimeLimit)
+		{
+			fail = true;
+			break;
+		}
+
+		iter++;
+	
+		if(iter > m_iterLimit)		
+		{
+			fail = true;
+			break;
+		}
+	
+		PNS_LINE *currentLine = lineStack.top();
+
+    	prof_start( &totalRealTime, false );
+    	nearest = node->NearestObstacle(currentLine, PNS_ITEM::ANY);		
+  		prof_end( &totalRealTime );
+
+  		TRACE(2,"t-nearestObstacle %lld us", (totalRealTime.value ));
+
+		if(!nearest)
+		{
+			if(lineStack.size() > 1)
+			{
+				PNS_LINE *original = lineStack.top(); 
+				PNS_LINE optimized;
+				int r_start, r_end;
+
+				original->GetAffectedRange(r_start, r_end);
+
+				TRACE(1, "Iter %d optimize-line [range %d-%d, total %d]", iter % r_start % r_end % original->GetCLine().PointCount() );
+				//lastWalkSolid = NULL;
+		    	prof_start( &totalRealTime, false );
+
+				if( optimizer.Optimize(original, &optimized) )
+				{
+					node->Remove(original);
+					optimizer.CacheRemove(original);
+					node->Add(&optimized);
+
+					if(original->BelongsTo(node))
+						delete original;
+				} 
+		  		prof_end( &totalRealTime );
+
+				TRACE(2,"t-optimizeObstacle %lld us", (totalRealTime.value ));
+
+			}
+			lineStack.pop();
+		} else {
+
+			switch(nearest->item->GetKind())
+			{
+				case PNS_ITEM::SEGMENT:
+				{
+					TRACE(1, "Iter %d shove-line", iter );
+
+					PNS_SEGMENT *pseg = static_cast<PNS_SEGMENT*>(nearest->item);
+					PNS_LINE *collidingLine = node->AssembleLine(pseg); 
+					PNS_LINE *shovedLine = collidingLine->CloneProperties();
+				
+			    	prof_start( &totalRealTime, false );
+					ShoveStatus st = shoveSingleLine(node, currentLine, collidingLine, *pseg, shovedLine);
+			  		prof_end( &totalRealTime );
+
+					TRACE(2,"t-shoveSingle %lld us", (totalRealTime.value ));
+
+					if(st == SH_OK)
+					{
+						node->Replace(collidingLine, shovedLine);
+
+						if(collidingLine->BelongsTo( node ))
+							delete collidingLine;
+
+						optimizer.CacheRemove(collidingLine);
+						lineStack.push( shovedLine );
+					} else 
+						fail = true;
+					
+					//lastWalkSolid = NULL;
+
+					break;
+				} // case SEGMENT
+
+				case PNS_ITEM::SOLID:
+				case PNS_ITEM::VIA:
+				{
+					TRACE(1, "Iter %d walkaround-solid [%p]", iter % nearest->item );
+					
+					if(lineStack.size() == 1)
+					{
+						fail = true;
+						break;
+					}
+
+/*					if(lastWalkSolid == nearest->item)
+					{
+						fail = true;
+						break;
+					}*/
+
+					PNS_WALKAROUND walkaround (node);
+					PNS_LINE *walkaroundLine = currentLine->CloneProperties();
+
+					walkaround.SetSolidsOnly(true);
+					walkaround.SetSingleDirection(true);
+					
+					prof_start( &totalRealTime, false );
+					walkaround.Route(*currentLine, *walkaroundLine, false);
+			  		prof_end( &totalRealTime );
+
+					TRACE(2,"t-walkSolid %lld us", (totalRealTime.value ));
+
+
+					node->Replace(currentLine, walkaroundLine);
+
+					if(currentLine->BelongsTo( node ))
+						delete currentLine;
+
+					optimizer.CacheRemove(currentLine);
+					lineStack.top() = walkaroundLine;
+
+					//lastWalkSolid = nearest->item;
+					break;
+				}
+				default:
+					break;
+			} // switch
+			if(fail)
+				break;
+		} 
+	}
+	
+	node->Remove(head);
+	delete head;
+	
+	if(headVia)
+	{
+		node->Remove(headVia);
+		delete headVia;
+	}
+
+	TRACE(1, "Shove status : %s after %d iterations" , (fail ? "FAILED" : "OK") % iter ); 
+	if(!fail)
+	{
+		pushSpringback(node, aCurrentHead, PNS_COST_ESTIMATOR());
+		return SH_OK;
+	} else {
+		delete node;
+		return SH_INCOMPLETE;
+	}
+}
+

pcbnew/router/pns_shove.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_SHOVE_H
+#define __PNS_SHOVE_H
+
+#include <vector>
+#include <stack>
+
+#include "pns_optimizer.h"
+
+class PNS_LINE;
+class PNS_NODE;
+class PNS_ROUTER;
+
+class PNS_SHOVE {
+
+	public:
+		PNS_SHOVE(PNS_NODE *aWorld);
+		~PNS_SHOVE();
+
+		enum ShoveStatus {
+			SH_OK = 0,
+			SH_NULL,
+			SH_INCOMPLETE
+		};
+
+		ShoveStatus ShoveLines(PNS_LINE* aCurrentHead);
+
+		PNS_NODE *GetCurrentNode()
+		{
+			return m_nodeStack.empty() ? m_root : m_nodeStack.back().node;
+		}
+
+		const PNS_COST_ESTIMATOR TotalCost() const;
+
+		void Reset();
+		void KillChildNodes();
+
+	private:
+
+		static const int ShoveTimeLimit = 3000;
+
+		bool tryShove(PNS_NODE *aWorld, PNS_LINE *aTrack, PNS_LINE * aObstacle, PNS_SEGMENT& aObstacleSeg, PNS_LINE *aResult, bool aInvertWinding );
+
+		ShoveStatus shoveSingleLine(PNS_NODE *aNode, PNS_LINE *aCurrent, PNS_LINE *aObstacle, PNS_SEGMENT& aObstacleSeg, PNS_LINE *aResult );
+
+		bool reduceSpringback( PNS_LINE *aHead );
+		bool pushSpringback( PNS_NODE *aNode, PNS_LINE *aHead, const PNS_COST_ESTIMATOR& aCost );
+
+		struct SpringbackTag {
+			int64_t length;
+			int segments;
+			VECTOR2I p;
+			PNS_NODE *node;
+			PNS_COST_ESTIMATOR cost;
+		};
+
+		std::vector<SpringbackTag> m_nodeStack;
+		PNS_NODE *m_root;
+		PNS_NODE *m_currentNode;
+		int m_iterLimit;
+};
+
+#endif

pcbnew/router/pns_solid.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <math/vector2d.h>
+
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_rect.h>
+#include <geometry/shape_circle.h>
+
+#include "pns_solid.h"
+#include "pns_utils.h"
+
+const SHAPE_LINE_CHAIN PNS_SOLID::Hull(int aClearance, int aWalkaroundThickness) const
+{
+	switch(m_shape->Type())
+	{
+		case SH_RECT:
+		{
+			SHAPE_RECT *rect = static_cast<SHAPE_RECT*> (m_shape);
+			return OctagonalHull( 	rect->GetPosition(), 
+									rect->GetSize(), 
+									aClearance + 1, 
+									0.2 * aClearance );
+		}
+
+		case SH_CIRCLE:
+		{
+			SHAPE_CIRCLE *circle = static_cast<SHAPE_CIRCLE*> (m_shape);
+			int r = circle->GetRadius();
+			return OctagonalHull( 	circle->GetCenter() - VECTOR2I(r, r), 
+									VECTOR2I(2 * r, 2 * r), 
+									aClearance + 1, 
+									0.52 * (r + aClearance) );
+		}
+		default:
+			break;
+	}
+
+	return SHAPE_LINE_CHAIN();
+}
+
+PNS_ITEM *PNS_SOLID::Clone() const
+{
+	// solids are never cloned as the shove algorithm never moves them
+	assert(false);
+}
\ No newline at end of file

pcbnew/router/pns_solid.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_SOLID_H
+#define __PNS_SOLID_H
+
+#include <math/vector2d.h>
+
+#include <geometry/seg.h>
+#include <geometry/shape.h>
+#include <geometry/shape_line_chain.h>
+
+#include "pns_item.h"
+
+class PNS_SOLID : public PNS_ITEM {
+public:
+	PNS_SOLID() : PNS_ITEM(SOLID)
+	{
+		m_movable = false;
+		m_shape = NULL;
+	}
+		
+	PNS_ITEM *Clone() const;
+	
+	const SHAPE* GetShape() const { return m_shape; }
+
+	const SHAPE_LINE_CHAIN Hull(int aClearance = 0, int aWalkaroundThickness = 0) const;
+
+	void SetShape( SHAPE* shape)
+	{
+		if(m_shape)
+			delete m_shape;
+		m_shape = shape;
+	}
+
+	const VECTOR2I& GetCenter() const
+	{
+		return m_center;
+	}
+
+	void SetCenter( const VECTOR2I& aCenter )
+	{
+		m_center = aCenter;
+	}
+
+private:
+
+	VECTOR2I m_center;
+	SHAPE* m_shape;
+};
+
+#endif
+

pcbnew/router/pns_utils.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include "pns_utils.h"
+#include "pns_line.h"
+#include "pns_router.h"
+
+const SHAPE_LINE_CHAIN OctagonalHull(const VECTOR2I& aP0, const VECTOR2I& aSize, int aClearance, int aChamfer)
+{
+	SHAPE_LINE_CHAIN s;
+
+	s.SetClosed( true );
+	
+	s.Append(aP0.x - aClearance ,			 			aP0.y - aClearance + aChamfer);
+	s.Append(aP0.x - aClearance + aChamfer, 			aP0.y - aClearance);
+	s.Append(aP0.x + aSize.x + aClearance - aChamfer, 	aP0.y - aClearance);
+	s.Append(aP0.x + aSize.x + aClearance, 				aP0.y - aClearance + aChamfer);
+	s.Append(aP0.x + aSize.x + aClearance, 				aP0.y + aSize.y + aClearance - aChamfer);
+	s.Append(aP0.x + aSize.x + aClearance - aChamfer, 	aP0.y + aSize.y + aClearance);
+	s.Append(aP0.x - aClearance + aChamfer, 			aP0.y + aSize.y + aClearance);
+	s.Append(aP0.x - aClearance, 						aP0.y + aSize.y + aClearance - aChamfer);
+	
+	return s;
+}
+

pcbnew/router/pns_utils.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_UTILS_H
+#define __PNS_UTILS_H
+
+#include <math/vector2d.h>
+#include <geometry/shape_line_chain.h>
+
+
+/** Various utility functions */
+
+const SHAPE_LINE_CHAIN OctagonalHull(const VECTOR2I& aP0, const VECTOR2I& aSize, int aClearance, int aChamfer);
+
+#endif // __PNS_UTILS_H
+

pcbnew/router/pns_via.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include "pns_via.h"
+#include "pns_node.h"
+#include "pns_utils.h"
+
+#include <geometry/shape_rect.h>
+
+static bool Circle2Circle( VECTOR2I p1, VECTOR2I p2, int r1, int r2, VECTOR2I& force )
+{
+
+	int mindist = r1 + r2;
+	VECTOR2I delta = p2 - p1;
+	int dist = delta.EuclideanNorm();
+	
+	if(dist >= mindist)
+		return false;
+	
+	force = delta.Resize(abs(mindist - dist) + 1);
+	return true;
+};
+
+static bool Rect2Circle( VECTOR2I rp0, VECTOR2I rsize, VECTOR2I cc, int cr, VECTOR2I& force )
+{
+	VECTOR2I vts[] = { 	VECTOR2I(rp0.x, 		  rp0.y),
+						VECTOR2I(rp0.x, 		  rp0.y + rsize.y),
+						VECTOR2I(rp0.x + rsize.x, rp0.y + rsize.y),
+						VECTOR2I(rp0.x + rsize.x, rp0.y),
+						VECTOR2I(rp0.x, 		  rp0.y) };
+
+	int dist = INT_MAX;
+	VECTOR2I nearest;
+
+	for (int i = 0; i < 4; i++)
+	{
+		SEG s(vts[i], vts[i+1]);
+		
+		VECTOR2I pn = s.NearestPoint( cc );
+
+		int d = (pn - cc).EuclideanNorm();
+		if( d < dist )
+		{
+			nearest = pn;
+			dist = d;
+		}
+	}
+
+		bool inside =  cc.x >= rp0.x && cc.x <= (rp0.x + rsize.x) 
+				&& cc.y >= rp0.y && cc.y <= (rp0.y + rsize.y);
+
+	VECTOR2I delta = cc - nearest;
+
+	if(dist >= cr && !inside)
+		return false;
+
+	if(inside)
+		force = -delta.Resize(abs(cr + dist) + 1);
+	else
+		force = delta.Resize(abs(cr - dist) + 1);
+
+	return true;
+};
+
+
+static bool ShPushoutForce ( const SHAPE *shape, VECTOR2I p, int r, VECTOR2I& force, int clearance)
+{
+	switch(shape->Type())
+	{
+		case SH_CIRCLE:
+		{
+			const SHAPE_CIRCLE *cir = static_cast<const SHAPE_CIRCLE*>(shape);
+			return Circle2Circle( cir->GetCenter(), p, cir->GetRadius(), r + clearance + 1, force );
+		}
+		case SH_RECT:
+		{
+			const SHAPE_RECT *rect = static_cast<const SHAPE_RECT*>(shape);
+			return Rect2Circle( rect->GetPosition(), rect->GetSize(), p, r + clearance + 1, force );
+		}
+		default:
+			return false;
+
+	}
+	return false;
+}
+
+
+bool PNS_VIA::PushoutForce ( PNS_NODE *aNode, const VECTOR2I &aDirection, VECTOR2I& aForce, bool aSolidsOnly, int aMaxIterations)
+{
+	int iter = 0;
+	PNS_VIA mv ( *this);
+	VECTOR2I force, totalForce;
+
+	while(iter < aMaxIterations)
+	{
+		PNS_NODE::OptObstacle obs = aNode->CheckColliding( &mv, aSolidsOnly ? PNS_ITEM::SOLID : PNS_ITEM::ANY);
+	
+		if(!obs)
+			break;
+
+		int clearance = aNode->GetClearance(obs->item, &mv);
+
+		if(iter > 10)
+		{
+			VECTOR2I l = - aDirection.Resize(m_diameter / 4);
+			totalForce += l;
+			mv.SetPos(mv.GetPos() + l);
+		}
+
+		if( ShPushoutForce(obs->item->GetShape(), mv.GetPos(), mv.GetDiameter() / 2, force, clearance) )
+		{
+			totalForce += force;
+			mv.SetPos(mv.GetPos() + force);
+		} 
+
+
+		iter++;
+	}
+
+	if(iter == aMaxIterations)
+		return false;
+
+	aForce = totalForce;
+	return true;
+}
+
+const SHAPE_LINE_CHAIN PNS_VIA::Hull(int aClearance, int aWalkaroundThickness) const
+{
+	return OctagonalHull( m_pos - VECTOR2I(m_diameter/2, m_diameter/2), VECTOR2I(m_diameter, m_diameter), aClearance + 1, (2*aClearance + m_diameter) * 0.26);
+}
+	
\ No newline at end of file

pcbnew/router/pns_via.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_VIA_H
+#define __PNS_VIA_H
+
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_circle.h>
+
+#include "pns_item.h"
+
+class PNS_NODE;
+
+class PNS_VIA : public PNS_ITEM 
+{
+	public:
+		PNS_VIA( ):
+			PNS_ITEM (VIA) {};
+
+		PNS_VIA( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aDiameter, int aNet = -1) :
+			PNS_ITEM (VIA) {
+				SetNet(aNet);
+				SetLayers(aLayers);
+				m_pos = aPos;
+				m_diameter = aDiameter;
+				m_shape = SHAPE_CIRCLE(aPos, aDiameter/2);
+			};
+
+
+		PNS_VIA(const PNS_VIA& b) : PNS_ITEM(VIA)
+		{
+			SetNet(b.GetNet());
+			SetLayers(b.GetLayers());
+			m_pos = b.m_pos;
+			m_diameter = b.m_diameter;
+			m_shape = SHAPE_CIRCLE(m_pos, m_diameter/2);
+		}
+
+		const VECTOR2I& GetPos() const
+		{
+			return m_pos;
+		}
+
+		void SetPos( const VECTOR2I& aPos ) 
+		{
+			m_pos = aPos;
+			m_shape.SetCenter(aPos);
+		}
+
+		int GetDiameter() const
+		{
+			return m_diameter;
+		}
+
+		void SetDiameter(int aDiameter)
+		{
+			m_diameter = aDiameter;
+			m_shape.SetRadius(m_diameter/2);
+		}
+
+		int GetDrill() const
+		{
+			return m_drill;
+		}
+
+		void SetDrill(int aDrill)
+		{
+			m_drill = aDrill;
+		}
+
+		bool PushoutForce ( PNS_NODE *aNode, const VECTOR2I &aDirection, VECTOR2I& aForce, bool aSolidsOnly = true, int aMaxIterations = 10);
+
+		const SHAPE *GetShape() const
+		{
+			return &m_shape;
+		}
+
+		PNS_VIA *Clone() const
+		{
+			PNS_VIA *v = new PNS_VIA();
+
+			v->SetNet(GetNet());
+			v->SetLayers(GetLayers());
+			v->m_pos = m_pos;
+			v->m_diameter = m_diameter;
+			v->m_shape = SHAPE_CIRCLE(m_pos, m_diameter/2);
+		
+			return v;
+		}
+
+		const SHAPE_LINE_CHAIN Hull(int aClearance = 0, int aWalkaroundThickness = 0) const;
+
+	private:
+		
+		int m_diameter;
+		int m_drill;
+		VECTOR2I m_pos;
+		SHAPE_CIRCLE m_shape;
+};
+
+#endif

pcbnew/router/pns_walkaround.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <vector>
+
+#include <boost/foreach.hpp>
+#include <boost/optional.hpp>
+
+#include <geometry/shape_line_chain.h>
+
+#include "pns_walkaround.h"
+#include "pns_optimizer.h"
+#include "pns_utils.h"
+#include "pns_router.h"
+
+using namespace std;
+using boost::optional;
+
+void PNS_WALKAROUND::start( const PNS_LINE& aInitialPath )
+{
+	m_iteration = 0;
+	m_iteration_limit = 50;
+}
+
+
+PNS_NODE::OptObstacle PNS_WALKAROUND::nearestObstacle(const PNS_LINE& aPath)
+{
+	return m_world->NearestObstacle ( &aPath, m_solids_only ? (PNS_ITEM::SOLID | PNS_ITEM::VIA) : PNS_ITEM::ANY );
+}
+
+
+PNS_WALKAROUND::WalkaroundStatus PNS_WALKAROUND::singleStep(PNS_LINE& aPath, bool aWindingDirection)
+{
+	optional<PNS_OBSTACLE>& current_obs = aWindingDirection ? m_currentObstacle[0] : m_currentObstacle[1];
+	bool& prev_recursive = aWindingDirection ? m_recursiveCollision[0] : m_recursiveCollision[1];
+	
+	if(!current_obs)
+		return DONE;
+
+	SHAPE_LINE_CHAIN path_pre[2], path_walk[2], path_post[2];
+
+	VECTOR2I last = aPath.GetCLine().CPoint(-1);
+
+	if((current_obs->hull).PointInside(last))
+	{
+		m_recursiveBlockageCount ++;
+
+		if(m_recursiveBlockageCount < 3)
+			aPath.GetLine().Append( current_obs->hull.NearestPoint(last) );
+		else {
+			aPath = aPath.ClipToNearestObstacle(m_world);
+			return STUCK;
+		}
+	}
+
+	aPath.NewWalkaround(current_obs->hull, path_pre[0], path_walk[0], path_post[0], aWindingDirection);
+	aPath.NewWalkaround(current_obs->hull, path_pre[1], path_walk[1], path_post[1], !aWindingDirection);
+
+
+	int len_pre = path_walk[0].Length();
+	int len_alt = path_walk[1].Length();
+		
+	PNS_LINE walk_path (aPath, path_walk[1]);
+		
+	bool alt_collides = m_world->CheckColliding(&walk_path, m_solids_only ? PNS_ITEM::SOLID : PNS_ITEM::ANY);
+
+	SHAPE_LINE_CHAIN pnew;
+
+	if(!m_forceSingleDirection && len_alt < len_pre && !alt_collides && !prev_recursive)
+	{
+		pnew = path_pre[1];
+		pnew.Append(path_walk[1]);
+		pnew.Append(path_post[1]);
+		
+		current_obs = nearestObstacle(PNS_LINE(aPath, path_post[1]));
+		prev_recursive = false;
+	} else {
+		pnew = path_pre[0];
+		pnew.Append(path_walk[0]);
+		pnew.Append(path_post[0]);
+	
+		current_obs = nearestObstacle(PNS_LINE(aPath, path_walk[0]));
+
+		if(!current_obs)
+		{
+			prev_recursive = false;
+			current_obs = nearestObstacle(PNS_LINE(aPath, path_post[0]));
+		} else
+			prev_recursive = true;
+	}
+
+		
+	pnew.Simplify();
+	aPath.SetShape(pnew);
+
+	return IN_PROGRESS;
+}
+
+PNS_WALKAROUND::WalkaroundStatus PNS_WALKAROUND::Route( const PNS_LINE& aInitialPath, PNS_LINE& aWalkPath, bool aOptimize )
+{
+	PNS_LINE path_cw(aInitialPath), path_ccw(aInitialPath);
+	WalkaroundStatus s_cw = IN_PROGRESS, s_ccw = IN_PROGRESS;
+	SHAPE_LINE_CHAIN best_path;
+
+	start(aInitialPath);
+
+	m_currentObstacle[0] = m_currentObstacle[1] = nearestObstacle(aInitialPath);
+	m_recursiveBlockageCount = 0;
+
+	aWalkPath = aInitialPath;
+
+	while(m_iteration < m_iteration_limit)
+	{
+		if(s_cw != STUCK)
+			s_cw = singleStep(path_cw, true);
+			
+		if(s_ccw != STUCK)
+			s_ccw = singleStep(path_ccw, false);
+
+		if((s_cw == DONE && s_ccw == DONE) || (s_cw == STUCK && s_ccw == STUCK))
+		{
+			int len_cw = path_cw.GetCLine().Length();
+			int len_ccw = path_ccw.GetCLine().Length();
+
+
+			if(m_forceLongerPath)
+				aWalkPath = (len_cw > len_ccw ? path_cw : path_ccw);
+			else
+				aWalkPath = (len_cw < len_ccw ? path_cw : path_ccw);
+
+			break;
+		} else if(s_cw == DONE && !m_forceLongerPath) {
+			aWalkPath = path_cw;
+			break;
+		} else if (s_ccw == DONE && !m_forceLongerPath) {
+			aWalkPath = path_ccw;
+			break;
+		}
+
+
+		m_iteration++;
+	}
+
+	if(m_iteration == m_iteration_limit)
+	{
+		int len_cw = path_cw.GetCLine().Length();
+		int len_ccw = path_ccw.GetCLine().Length();
+
+
+		if(m_forceLongerPath)
+			aWalkPath = (len_cw > len_ccw ? path_cw : path_ccw);
+		else
+			aWalkPath = (len_cw < len_ccw ? path_cw : path_ccw);
+
+	}
+
+	if(m_cursorApproachMode)
+	{
+		//int len_cw = path_cw.GetCLine().Length();
+		//int len_ccw = path_ccw.GetCLine().Length();
+		bool found = false;
+
+		SHAPE_LINE_CHAIN l = aWalkPath.GetCLine();
+
+			
+			for(int i = 0; i < l.SegmentCount(); i++)
+			{
+				const SEG s = l.Segment(i);
+
+				VECTOR2I nearest = s.NearestPoint(m_cursorPos);
+				VECTOR2I::extended_type dist_a = (s.a - m_cursorPos).SquaredEuclideanNorm();
+				VECTOR2I::extended_type dist_b = (s.b - m_cursorPos).SquaredEuclideanNorm();
+				VECTOR2I::extended_type dist_n = (nearest - m_cursorPos).SquaredEuclideanNorm();
+
+
+			
+				if(dist_n <= dist_a && dist_n < dist_b)
+				{
+					//PNSDisplayDebugLine(l, 3);
+					l.Remove(i + 1, -1);
+					l.Append( nearest );
+					l.Simplify();
+					found = true;
+					break;
+				}
+			}
+			if(found)
+			{
+				aWalkPath =  aInitialPath;
+				aWalkPath.SetShape(l);
+			}
+		}
+
+
+	aWalkPath.SetWorld(m_world);
+	aWalkPath.GetLine().Simplify();
+
+	WalkaroundStatus st = s_ccw == DONE || s_cw == DONE ? DONE : STUCK;
+
+	if(aOptimize && st == DONE)
+		PNS_OPTIMIZER::Optimize(&aWalkPath, PNS_OPTIMIZER::MERGE_OBTUSE, m_world);
+
+	return st;
+}

pcbnew/router/pns_walkaround.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __PNS_WALKAROUND_H
+#define __PNS_WALKAROUND_H
+
+#include "pns_line.h"
+#include "pns_node.h"
+
+class PNS_WALKAROUND {
+	
+	static const int DefaultIterationLimit = 50;
+
+
+
+	public:
+		PNS_WALKAROUND( PNS_NODE *aWorld ):
+			m_world(aWorld), m_iteration_limit(DefaultIterationLimit) {
+				m_forceSingleDirection = false;
+				m_forceLongerPath = false;
+				m_cursorApproachMode = false;
+			};
+		~PNS_WALKAROUND() {};
+
+		enum WalkaroundStatus {
+			IN_PROGRESS = 0,
+			DONE,
+			STUCK
+		};
+
+		void SetWorld ( PNS_NODE *aNode )
+		{
+			m_world = aNode;
+		}
+
+		void SetIterationLimit( const int aIterLimit )
+		{
+			m_iteration_limit = aIterLimit;
+		}
+
+		void SetSolidsOnly ( bool aSolidsOnly )
+		{
+			m_solids_only = aSolidsOnly;
+		}
+
+
+		void SetSingleDirection (bool aForceSingleDirection  )
+		{
+			m_forceSingleDirection = aForceSingleDirection;
+			m_forceLongerPath = true;
+		}	
+
+		void SetApproachCursor ( bool aEnabled, const VECTOR2I& aPos )
+		{
+			m_cursorPos = aPos;
+			m_cursorApproachMode = aEnabled;
+		}
+		
+
+		WalkaroundStatus Route( const PNS_LINE& aInitialPath, PNS_LINE& aWalkPath, bool aOptimize = true);
+
+	private:
+		void start( const PNS_LINE& aInitialPath );
+
+		WalkaroundStatus singleStep(PNS_LINE& aPath, bool aWindingDirection);
+		PNS_NODE::OptObstacle nearestObstacle(const PNS_LINE& aPath);
+
+		PNS_NODE *m_world;
+		
+		int m_recursiveBlockageCount;
+		int m_iteration;
+		int m_iteration_limit;
+		bool m_solids_only;
+		bool m_forceSingleDirection, m_forceLongerPath;
+		bool m_cursorApproachMode;
+		VECTOR2I m_cursorPos;
+		PNS_NODE::OptObstacle m_currentObstacle[2];
+		bool m_recursiveCollision[2];
+};
+
+#endif // __PNS_WALKAROUND_H
+

pcbnew/router/router_preview_item.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+ 
+#include <gal/color4d.h>
+
+#include "class_track.h"
+#include <pcb_painter.h>
+
+#include "router_preview_item.h"
+
+#include "pns_line.h"
+#include "pns_segment.h"
+#include "pns_via.h"
+
+using namespace KiGfx;
+
+ROUTER_PREVIEW_ITEM::ROUTER_PREVIEW_ITEM( const PNS_ITEM *aItem, VIEW_GROUP *aParent ) 
+	: EDA_ITEM( NOT_USED )
+		{
+			m_Flags = 0;
+			m_parent = aParent;
+			if(aItem)
+				Update(aItem);
+		}
+	
+ROUTER_PREVIEW_ITEM::~ROUTER_PREVIEW_ITEM()
+{
+	
+}
+			
+void ROUTER_PREVIEW_ITEM::Update(const PNS_ITEM *aItem)
+{
+	m_layer = aItem->GetLayers().Start();
+
+
+	m_color = getLayerColor( m_layer );
+	m_color.a = 0.8;
+		
+	switch(aItem->GetKind())
+	{
+		case PNS_ITEM::LINE:
+			m_type = PR_LINE;
+			m_width = static_cast<const PNS_LINE *>(aItem)->GetWidth();
+			m_line = * static_cast<const SHAPE_LINE_CHAIN *>(aItem->GetShape());
+			break;
+
+		case PNS_ITEM::SEGMENT:
+			m_type = PR_LINE;
+			m_width = static_cast<const PNS_SEGMENT *>(aItem)->GetWidth();
+			m_line = * static_cast<const SHAPE_LINE_CHAIN *>(aItem->GetShape());
+			break;
+
+		case PNS_ITEM::VIA:
+			m_type = PR_VIA;
+			m_color = COLOR4D(0.7, 0.7, 0.7, 0.8);
+			m_width = static_cast<const PNS_VIA *>(aItem)->GetDiameter();
+			m_viaCenter = static_cast<const PNS_VIA *>(aItem)->GetPos();
+			break;
+
+		default:
+			break;	
+	}
+	
+	ViewSetVisible(true);
+	ViewUpdate(GEOMETRY | APPEARANCE);
+}
+
+void ROUTER_PREVIEW_ITEM::MarkAsHead( )
+{
+	if(m_type != PR_VIA)
+		m_color.Saturate(1.0);
+}
+
+const BOX2I ROUTER_PREVIEW_ITEM::ViewBBox() const 
+{
+	BOX2I bbox;
+
+	switch(m_type)
+	{
+		case PR_LINE:
+			bbox = m_line.BBox();
+			bbox.Inflate( m_width / 2);
+			return bbox;
+		case PR_VIA:
+			bbox = BOX2I( m_viaCenter, VECTOR2I(0, 0));
+			bbox.Inflate( m_width / 2);
+			return bbox;
+		default:
+			break;
+	}
+	return bbox;	
+}
+
+void ROUTER_PREVIEW_ITEM::ViewDraw( int aLayer, KiGfx::GAL* aGal ) const
+{
+	switch( m_type )
+	{
+		case PR_LINE:
+
+			aGal->SetLayerDepth(-100.0);
+			aGal->SetLineWidth(m_width);
+	    	aGal->SetStrokeColor(m_color);
+	    	aGal->SetIsStroke(true);
+	    	aGal->SetIsFill(false);
+	    	for(int s= 0 ; s < m_line.SegmentCount(); s++)
+	    		aGal->DrawLine(m_line.CSegment(s).a, m_line.CSegment(s).b);
+	    	if(m_line.IsClosed())
+	    		aGal->DrawLine(m_line.CSegment(-1).b, m_line.CSegment(0).a);
+	    	break;
+	    case PR_VIA:
+    		
+    		aGal->SetLayerDepth(-101.0);
+			aGal->SetIsStroke(false);
+    		aGal->SetIsFill(true);
+    		aGal->SetFillColor(m_color);
+    		aGal->DrawCircle(m_viaCenter, m_width / 2);
+			break;
+		default:
+			break;
+	}
+}
+
+
+void ROUTER_PREVIEW_ITEM::DebugLine ( const SHAPE_LINE_CHAIN& aLine, int aWidth , int aStyle  )
+{
+#if 0
+	m_line = aLine;
+	m_width = aWidth;
+	m_color = assignColor(aStyle);
+	
+
+	m_type = PR_LINE;
+	ViewUpdate(GEOMETRY | APPEARANCE);
+#endif
+}
+
+void ROUTER_PREVIEW_ITEM::DebugBox ( const BOX2I& aBox, int aStyle )
+{
+#if 0
+	assert(false);
+
+	m_line.Clear();
+	m_line.Append( aBox.GetX(), aBox.GetY() );
+	m_line.Append( aBox.GetX() + aBox.GetWidth(), aBox.GetY() + aBox.GetHeight());
+	m_line.Append( aBox.GetX() + aBox.GetWidth(), aBox.GetY() + aBox.GetHeight());
+	m_line.Append( aBox.GetX(), aBox.GetY() + aBox.GetHeight());
+	m_line.SetClosed(true);
+	m_width = 20000;
+	m_color = assignColor(aStyle);
+	m_type = PR_LINE;
+	ViewUpdate(GEOMETRY | APPEARANCE);
+#endif
+}
+		
+const COLOR4D ROUTER_PREVIEW_ITEM::getLayerColor (int layer ) const
+{
+	//assert (m_view != NULL);
+
+	PCB_RENDER_SETTINGS *settings = static_cast <PCB_RENDER_SETTINGS*> (m_parent -> GetView() -> GetPainter() -> GetSettings());
+	return settings->GetLayerColor(layer);
+}
+
+
+const COLOR4D ROUTER_PREVIEW_ITEM::assignColor ( int style ) const
+{
+	COLOR4D color;
+	switch(style)
+	{
+    case 0: color =COLOR4D(0, 1, 0, 1);break;
+    case 1: color =COLOR4D(1, 0, 0, 0.3);break;
+    case 2: color =COLOR4D(1, 0.5, 0.5, 1);break;
+    case 3: color =COLOR4D(0, 0, 1, 1);break;
+    case 4: color =COLOR4D(1, 1, 1, 1); break;
+    case 5: color =COLOR4D(1, 1, 0, 1); break;
+    case 6: color =COLOR4D(0, 1, 1, 1); break;
+    case 32: color =COLOR4D(0, 0, 1, 0.5); break;
+    default: break;
+	}
+	return color;
+}

pcbnew/router/router_preview_item.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+ 
+#ifndef __ROUTER_PREVIEW_ITEM_H
+#define __ROUTER_PREVIEW_ITEM_H
+
+#include <cstdio>
+
+#include <view/view.h>
+#include <view/view_item.h>
+#include <view/view_group.h>
+
+#include <math/vector2d.h>
+#include <math/box2.h>
+
+#include <geometry/shape_line_chain.h>
+#include <geometry/shape_circle.h>
+
+#include <gal/color4d.h>
+#include <gal/graphics_abstraction_layer.h>
+
+#include <layers_id_colors_and_visibility.h>
+
+class PNS_ITEM;
+class PNS_ROUTER;
+
+class ROUTER_PREVIEW_ITEM : public EDA_ITEM
+{
+	public:
+		enum ItemType {
+			PR_VIA,
+			PR_LINE,
+			PR_STUCK_MARKER
+		};
+
+		enum ItemFlags {
+			PR_SUGGESTION = 1
+		};
+
+		ROUTER_PREVIEW_ITEM( const PNS_ITEM *aItem = NULL, KiGfx::VIEW_GROUP *aParent = NULL );
+		~ROUTER_PREVIEW_ITEM();
+		
+		void Update ( const PNS_ITEM *aItem);
+
+		void StuckMarker( VECTOR2I& aPosition );
+		void DebugLine ( const SHAPE_LINE_CHAIN& aLine, int aWidth = 0, int aStyle = 0 );
+		void DebugBox ( const BOX2I& aBox, int aStyle = 0);
+		void Show(int a, std::ostream& b) const {};
+
+		const BOX2I ViewBBox() const;
+		
+		
+	    virtual void ViewDraw( int aLayer, KiGfx::GAL* aGal ) const;
+	    
+		virtual void ViewGetLayers( int aLayers[], int& aCount ) const
+		{
+			aLayers[0] = GP_OVERLAY;
+			aCount = 1;
+		}
+    
+    	void MarkAsHead( );
+
+	private:
+
+		const KiGfx::COLOR4D assignColor ( int style ) const;
+		const KiGfx::COLOR4D getLayerColor (int layer ) const;
+
+		KiGfx::VIEW_GROUP *m_parent;
+
+		PNS_ROUTER *m_router;
+		SHAPE_LINE_CHAIN m_line;
+
+		ItemType m_type;
+		int m_style;
+		int m_width;
+		int m_layer;
+
+		KiGfx::COLOR4D m_color;
+
+		VECTOR2I m_stuckPosition;
+		VECTOR2I m_viaCenter;
+
+};
+
+
+#endif

pcbnew/router/router_tool.cpp

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#include <boost/foreach.hpp>
+#include <boost/optional.hpp>
+
+#include "class_drawpanel_gal.h"
+#include "class_board_item.h"
+#include "class_board.h"
+
+#include <wxPcbStruct.h>
+#include <view/view_controls.h>
+#include <pcbcommon.h>
+#include <pcb_painter.h>
+
+#include <tool/context_menu.h>
+#include <tool/tool_action.h>
+
+#include "router_tool.h"
+#include "pns_segment.h"
+#include "pns_router.h"
+#include "trace.h"
+
+using namespace KiGfx;
+using namespace std;
+using boost::optional;
+
+static TOOL_ACTION ACT_AutoEndRoute     ( "AutoEndRoute", SCOPE_CONTEXT, 'F' );
+static TOOL_ACTION ACT_PlaceVia         ( "PlaceVia", SCOPE_CONTEXT, 'V' );
+static TOOL_ACTION ACT_OpenRouteOptions ( "OpenRouterOptions", SCOPE_CONTEXT, 'E' );
+static TOOL_ACTION ACT_SwitchPosture    ( "SwitchPosture", SCOPE_CONTEXT, '/' );
+static TOOL_ACTION ACT_EndTrack         ( "SwitchPosture", SCOPE_CONTEXT, WXK_END );
+
+ROUTER_TOOL::ROUTER_TOOL() :
+        TOOL_INTERACTIVE( "pcbnew.InteractiveRouter" )
+{
+	m_router = NULL; 
+    m_menu = new CONTEXT_MENU ;
+
+    m_menu->SetTitle( wxT( "Interactive router") ); // fixme: not implemented yet. Sorry.
+    m_menu->Add( wxT ("Cancel"), 0);
+    m_menu->Add( wxT ("New track"), 1);
+    m_menu->Add( wxT ("End track"), 2);
+    m_menu->Add( wxT ("Auto-end track"), 2);
+    m_menu->Add( wxT ("Place via"), 3);
+    m_menu->Add( wxT ("Switch posture"), 4);
+    
+    m_menu->Add( wxT ("Routing options..."), 5);
+}
+
+
+ROUTER_TOOL::~ROUTER_TOOL()
+{
+	delete m_router;
+}
+
+
+void ROUTER_TOOL::Reset()
+{
+ 
+    if(m_router)
+        delete m_router;
+
+    m_router = new PNS_ROUTER;
+
+    TRACEn(0,"Reset");
+    m_router->ClearWorld();
+    m_router->SetBoard( getModel <BOARD> (PCB_T) );
+    m_router->SyncWorld();
+
+    if(getView())
+        m_router->SetView( getView() );
+
+    Go( &ROUTER_TOOL::Main, TOOL_EVENT( TC_Command, TA_ActivateTool, GetName() ) );
+}
+
+int ROUTER_TOOL::getDefaultWidth( int aNetCode )
+{
+    int w, d1, d2;
+    getNetclassDimensions( aNetCode, w, d1, d2);
+    return w;
+}
+
+void ROUTER_TOOL::getNetclassDimensions ( int aNetCode, int& aWidth, int& aViaDiameter, int& aViaDrill)
+{
+    BOARD *board = getModel <BOARD> (PCB_T);
+ 
+    NETCLASS* netClass = NULL;
+    NETINFO_ITEM *ni = board->FindNet(aNetCode);
+    
+    if(ni)
+    {
+        wxString netClassName = ni->GetClassName();
+        netClass = board->m_NetClasses.Find( netClassName );
+    }
+
+    if( !netClass )
+        netClass = board->m_NetClasses.GetDefault();
+    
+    aWidth = netClass->GetTrackWidth();
+    aViaDiameter = netClass->GetViaDiameter();
+    aViaDrill = netClass->GetViaDrill();
+}
+
+
+PNS_ITEM *ROUTER_TOOL::pickSingleItem( const VECTOR2I& aWhere, int aNet, int aLayer )
+{
+    int tl = getView()->GetTopLayer();
+
+    if(aLayer > 0)
+        tl = aLayer;
+
+    PNS_ITEM *picked_seg = NULL, *picked_via = NULL;
+    PNS_ITEMSET candidates = m_router->QueryHoverItems(aWhere);
+
+    BOOST_FOREACH( PNS_ITEM *item,  candidates.Items() )
+    {
+        if( !IsCopperLayer(item->GetLayers().Start()) ) 
+            continue;
+
+        if( item->GetParent() && !item->GetParent()->ViewIsVisible() )
+            continue;
+
+        if( aNet < 0 || item->GetNet() == aNet )
+        {
+            if( item->OfKind (PNS_ITEM::VIA | PNS_ITEM::SOLID) )
+            {
+                if(item->GetLayers().Overlaps(tl) || !picked_via)
+                    picked_via = item; 
+            } else {
+                if(item->GetLayers().Overlaps(tl) || !picked_seg)
+                    picked_seg = item; 
+            }
+        }
+    }
+
+    if( DisplayOpt.ContrastModeDisplay )
+    {
+        if( picked_seg && !picked_seg->GetLayers().Overlaps(tl))
+            picked_seg = NULL;
+    }
+    
+    PNS_ITEM *rv = picked_via ? picked_via : picked_seg;
+
+    if( rv && aLayer >= 0 && !rv-> GetLayers().Overlaps(aLayer) )
+        rv = NULL;
+
+    if(rv)
+       TRACE(0, "%s, layer : %d, tl: %d", rv->GetKindStr().c_str() % rv->GetLayers().Start() % tl);
+
+    return rv;
+}
+
+    
+
+void ROUTER_TOOL::setMsgPanel ( bool enabled, int entry, const wxString& aUpperMessage, const wxString& aLowerMessage )
+{
+    PCB_EDIT_FRAME *frame = getEditFrame<PCB_EDIT_FRAME> ();
+    
+    if(m_panelItems.size() <= (unsigned int) entry)
+        m_panelItems.resize(entry + 1);
+        
+    m_panelItems[entry] = MSG_PANEL_ITEM( aUpperMessage, aLowerMessage, BLACK );
+    frame->SetMsgPanel(m_panelItems);
+}
+
+void ROUTER_TOOL::clearMsgPanel()
+{
+    PCB_EDIT_FRAME *frame = getEditFrame<PCB_EDIT_FRAME> ();
+
+    frame->ClearMsgPanel();
+}
+
+void ROUTER_TOOL::highlightNet(bool enabled, int netcode)
+{
+    RENDER_SETTINGS *rs = getView()->GetPainter()->GetSettings();
+    
+    if(netcode >= 0 && enabled)
+        rs->SetHighlight(true, netcode);
+    else    
+        rs->SetHighlight(false);    
+
+    getView()->UpdateAllLayersColor();
+}
+
+void ROUTER_TOOL::updateStartItem( TOOL_EVENT& aEvent )
+{
+    VIEW_CONTROLS *ctls = getViewControls();
+    int tl = getView()->GetTopLayer();
+    PNS_ITEM *startItem = NULL;
+
+    if( aEvent.IsMotion() || aEvent.IsClick() )
+    {
+        VECTOR2I p = aEvent.Position();
+        startItem = pickSingleItem(p);
+
+
+
+        if(startItem && startItem->GetNet() >= 0)
+        {
+            bool dummy;
+            VECTOR2I cursorPos = m_router->SnapToItem (startItem, p, dummy);
+            ctls->ForceCursorPosition(true, cursorPos);
+
+            m_startSnapPoint = cursorPos;
+            if(startItem->GetLayers().IsMultilayer())
+                m_startLayer = tl;
+            else
+                m_startLayer = startItem->GetLayers().Start();
+            
+            m_startItem = startItem;
+        } else {
+            m_startItem = NULL;
+            m_startSnapPoint = p;
+            m_startLayer = tl;
+            ctls->ForceCursorPosition(false);
+        }
+    }
+}
+
+void ROUTER_TOOL::updateEndItem( TOOL_EVENT& aEvent )
+{
+    VIEW_CONTROLS *ctls = getViewControls();
+    VECTOR2I p = aEvent.Position();
+    int layer;
+
+    if(m_router->GetCurrentNet() < 0 || !m_startItem)
+    {
+        m_endItem = NULL;
+        m_endSnapPoint = p;
+        return;
+    }
+
+    bool dummy;
+
+    if(m_router->IsPlacingVia())
+        layer = -1;
+    else 
+        layer = m_router->GetCurrentLayer();
+    
+    PNS_ITEM *endItem = pickSingleItem(p, m_startItem->GetNet(), layer );
+
+    if(endItem)
+    {
+        VECTOR2I cursorPos = m_router->SnapToItem (endItem, p, dummy);
+        ctls->ForceCursorPosition(true, cursorPos);
+        m_endItem = endItem;
+        m_endSnapPoint = cursorPos;
+    } else {
+        m_endItem = NULL;
+        m_endSnapPoint = p;
+        ctls->ForceCursorPosition(false);
+    }
+       
+    if(m_endItem)
+        TRACE(0, "%s, layer : %d", m_endItem->GetKindStr().c_str() % m_endItem->GetLayers().Start() );
+}
+
+void ROUTER_TOOL::startRouting ( )
+{
+    VIEW_CONTROLS *ctls = getViewControls();
+    
+    int width = getDefaultWidth( m_startItem ? m_startItem->GetNet() : -1);
+    if(m_startItem && m_startItem->OfKind(PNS_ITEM::SEGMENT))
+        width = static_cast<PNS_SEGMENT *>(m_startItem)->GetWidth();
+
+    m_router->SetCurrentWidth(width);
+    m_router->SwitchLayer(m_startLayer);
+
+    getEditFrame<PCB_EDIT_FRAME>() -> SetTopLayer (m_startLayer);
+
+    if(m_startItem && m_startItem->GetNet() >= 0)
+        highlightNet(true, m_startItem->GetNet() );
+
+    ctls->ForceCursorPosition(false);
+    ctls->SetAutoPan(true);
+    
+    m_router->StartRouting( m_startSnapPoint, m_startItem );
+
+    m_endItem = NULL;
+    m_endSnapPoint = m_startSnapPoint;
+
+    while( OPT_TOOL_EVENT evt = Wait() )
+    {
+          if( evt->IsCancel() )
+            break;  
+          else if (evt->IsMotion())
+          {
+            updateEndItem( *evt );
+            m_router->Move ( m_endSnapPoint, m_endItem );
+          }
+          else if (evt->IsClick (MB_Left ))
+          {
+            updateEndItem( *evt );
+            if(m_router->FixRoute(m_endSnapPoint, m_endItem))
+                break;
+            m_router->Move ( m_endSnapPoint, m_endItem );
+          } else if (evt->IsKeyUp())
+          {
+            switch( evt->KeyCode() )
+            {
+                case 'V':
+                    {
+                        int w, diameter, drill; 
+                        getNetclassDimensions( m_router->GetCurrentNet(), w, diameter, drill );
+                        m_router->SetCurrentViaDiameter(diameter);
+                        m_router->SetCurrentViaDrill(drill);
+                        m_router->ToggleViaPlacement();
+                        getEditFrame<PCB_EDIT_FRAME>() -> SetTopLayer (m_router->GetCurrentLayer());
+                        m_router->Move ( m_endSnapPoint, m_endItem );
+                        break;
+                    }
+                
+                case '/':
+                    m_router->FlipPosture();
+                    break;
+
+                case '+':
+                case '=':
+                    m_router->SwitchLayer ( m_router->NextCopperLayer (true) );
+                    updateEndItem( *evt );
+                    getEditFrame<PCB_EDIT_FRAME>() -> SetTopLayer (m_router->GetCurrentLayer());
+                    m_router->Move ( m_endSnapPoint, m_endItem );
+
+                    break;
+                
+                case '-':
+                    m_router->SwitchLayer ( m_router->NextCopperLayer (false) );
+                    getEditFrame<PCB_EDIT_FRAME>() -> SetTopLayer (m_router->GetCurrentLayer());
+                    m_router->Move ( m_endSnapPoint, m_endItem );
+                    break;
+            }
+          }
+    }
+
+   if(m_router->RoutingInProgress())
+        m_router->StopRouting();
+    
+    ctls->SetAutoPan(false);
+    ctls->ForceCursorPosition(false);
+    highlightNet(false);
+}
+
+
+int ROUTER_TOOL::Main( TOOL_EVENT& aEvent )
+{
+    VIEW_CONTROLS *ctls = getViewControls();
+
+    //SetContextMenu ( m_menu );
+    //setMsgPanel(true, 0, wxT("KiRouter"), wxT("Pick an item to start routing"));
+
+    ctls->SetSnapping ( true );
+    ctls->ShowCursor( true );
+
+    // Main loop: keep receiving events
+    while( OPT_TOOL_EVENT evt = Wait() )
+    {
+
+        if( evt->IsCancel() )
+          	break;  // Finish
+        else if( evt->IsMotion( ) )
+            updateStartItem( *evt );
+        else if( evt->IsClick ( MB_Left ) )
+        {
+            updateStartItem( *evt );
+            startRouting( );
+        }
+    }
+
+
+    //clearMsgPanel();
+
+    // Restore the default settings
+    ctls->SetAutoPan( false );
+    ctls->ShowCursor( false );
+
+    return 0;
+}
+
+

pcbnew/router/router_tool.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+
+#ifndef __ROUTER_TOOL_H
+#define __ROUTER_TOOL_H
+
+#include <set>
+#include <boost/shared_ptr.hpp>
+
+#include <math/vector2d.h>
+#include <tool/tool_interactive.h>
+
+#include <wxstruct.h>
+#include <msgpanel.h>
+
+#include "pns_layerset.h"
+
+class PNS_ROUTER;
+class PNS_ITEM;
+
+class ROUTER_TOOL : public TOOL_INTERACTIVE
+{
+public:
+    ROUTER_TOOL();
+    ~ROUTER_TOOL();
+
+    void Reset();
+    int Main( TOOL_EVENT& aEvent );
+
+private:
+	
+	PNS_ITEM *pickSingleItem( const VECTOR2I& aWhere, int aNet = -1, int aLayer = -1 );
+	
+
+	void setMsgPanel ( bool enabled, int entry, const wxString& aUpperMessage = wxT(""), const wxString& aLowerMessage = wxT("") );
+	void clearMsgPanel();
+
+	int getDefaultWidth( int aNetCode );
+	void startRouting ( );
+	void highlightNet(bool enabled, int netcode = -1);
+
+	void updateStartItem( TOOL_EVENT& aEvent );
+	void updateEndItem( TOOL_EVENT& aEvent );
+
+	void getNetclassDimensions ( int aNetCode, int& aWidth, int& aViaDiameter, int& aViaDrill);
+
+	MSG_PANEL_ITEMS m_panelItems;
+
+	PNS_ROUTER *m_router;
+
+	PNS_ITEM *m_startItem;
+	int m_startLayer;
+	VECTOR2I m_startSnapPoint;
+
+	PNS_ITEM *m_endItem;
+	VECTOR2I m_endSnapPoint;
+
+    /*boost::shared_ptr<CONTEXT_MENU> m_menu;*/
+    CONTEXT_MENU * m_menu;
+};
+
+#endif

pcbnew/router/trace.h

+/*
+ * KiRouter - a push-and-(sometimes-)shove PCB router
+ *
+ * Copyright (C) 2013  CERN
+ * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+ * 
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.or/licenses/>.
+ */
+ 
+#ifndef __TRACE_H
+#define __TRACE_H
+
+
+#ifdef DEBUG
+
+#include <string>
+#include <iostream>
+#include <boost/format.hpp>
+
+static void _trace_print(const char *funcName, int level, const std::string& msg)
+{
+	std::cerr << "trace[" << level << "]: " << funcName << ": " << msg << std::endl;
+}
+
+
+
+#define TRACE(level, fmt, ...) \
+	_trace_print(__FUNCTION__, level, (boost::format(fmt) % __VA_ARGS__).str() );
+
+#define TRACEn(level, msg) \
+	_trace_print(__FUNCTION__, level, std::string(msg));
+
+#else
+
+#define TRACE(level, fmt, ...)
+#define TRACEn(level, msg)
+
+#endif
+
+#endif