From 5fc7103425732403a0b8e6f092430a2996138488 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Wed, 6 Mar 2013 20:31:47 +0000
Subject: [PATCH 01/15] First attempt at pathfinding using boost::graph

---
 apps/openmw/mwmechanics/aitravel.cpp | 193 ++++++++++++++++++++++++++-
 apps/openmw/mwmechanics/aitravel.hpp |   7 +-
 2 files changed, 196 insertions(+), 4 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 897dd17480..b5e67e449b 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -1,8 +1,19 @@
 #include "aitravel.hpp"
 #include <iostream>
 
+#include "character.hpp"
+
+#include "../mwworld/class.hpp"
+#include "../mwbase/world.hpp"
+#include "../mwbase/environment.hpp"
+#include "movement.hpp"
+
+#include <boost/graph/astar_search.hpp>
+#include <boost/graph/adjacency_list.hpp>
+#include "boost/tuple/tuple.hpp"
+
 MWMechanics::AiTravel::AiTravel(float x, float y, float z)
-: mX(x),mY(y),mZ(z)
+: mX(x),mY(y),mZ(z),isPathConstructed(false)
 {
 }
 
@@ -11,10 +22,186 @@ MWMechanics::AiTravel * MWMechanics::AiTravel::clone() const
     return new AiTravel(*this);
 }
 
+float distance(ESM::Pathgrid::Point point,float x,float y,float z)
+{
+    return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+(point.mZ - z)*(point.mZ - z));
+}
+
+float distance(ESM::Pathgrid::Point a,ESM::Pathgrid::Point b)
+{
+    return sqrt(float(a.mX - b.mX)*(a.mX - b.mX)+(a.mY - b.mY)*(a.mY - b.mY)+(a.mZ - b.mZ)*(a.mZ - b.mZ));
+}
+
+int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
+{
+    if(!grid) throw std::exception("NULL PathGrid!");
+    if(grid->mPoints.empty()) throw std::exception("empty PathGrid!");
+
+    float m = distance(grid->mPoints[0],x,y,z);
+    int i0 = 0;
+
+    for(int i=1; i<grid->mPoints.size();i++)
+    {
+        if(distance(grid->mPoints[i],x,y,z)<m)
+        {
+            m = distance(grid->mPoints[i],x,y,z);
+            i0 = i;
+        }
+    }
+
+    return i0;
+}
+
+float sgn(float a)
+{
+    if(a>0) return 1.;
+    else return -1.;
+}
+
+float getZAngle(float dX,float dY)
+{
+    float h = sqrt(dX*dX+dY*dY);
+    return Ogre::Radian(acos(dY/h)*sgn(asin(dX/h))).valueDegrees();
+}
+
+struct Edge
+{
+    float distance;
+};
+
+typedef boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,
+    boost::property<boost::vertex_index_t,int,ESM::Pathgrid::Point>,boost::property<boost::edge_weight_t,float> > PathGridGraph;
+typedef boost::property_map<PathGridGraph, boost::edge_weight_t>::type WeightMap;
+typedef PathGridGraph::vertex_descriptor PointID;
+typedef PathGridGraph::edge_descriptor   PointConnectionID;
+
+struct found_path {};
+
+class goalVisited : public boost::default_astar_visitor
+{
+public:
+    goalVisited(PointID goal) : mGoal(goal) {}
+    
+    void examine_vertex(PointID u, const PathGridGraph g)
+    {
+        if(u == mGoal)
+            throw found_path();
+    }
+private:
+    PointID mGoal;
+};
+
+class DistanceHeuristic : public boost::astar_heuristic <PathGridGraph, float>
+{
+public:
+    DistanceHeuristic(const PathGridGraph & l, PointID goal)
+    : mGraph(l), mGoal(goal) {}
+ 
+    float operator()(PointID u)
+    {
+        const ESM::Pathgrid::Point & U = mGraph[u];
+        const ESM::Pathgrid::Point & V = mGraph[mGoal];
+        float dx = U.mX - V.mX;
+        float dy = U.mY - V.mY;
+        float dz = U.mZ - V.mZ;
+        return sqrt(dx * dx + dy * dy + dz * dz);
+    }
+private:
+    const PathGridGraph & mGraph;
+    PointID mGoal;
+};
+
+std::list<ESM::Pathgrid::Point> getPath(PointID start,PointID end,PathGridGraph graph){
+    std::vector<PointID> p(boost::num_vertices(graph));
+    std::vector<float> d(boost::num_vertices(graph));
+    std::list<ESM::Pathgrid::Point> shortest_path;
+
+    try {
+        boost::astar_search
+            (
+            graph,
+            start,
+            DistanceHeuristic(graph,end),
+            boost::predecessor_map(&p[0]).distance_map(&d[0]).visitor(goalVisited(end))//.weight_map(boost::get(&Edge::distance, graph))
+            );
+
+    } catch(found_path fg) {
+        for(PointID v = end;; v = p[v]) {
+            shortest_path.push_front(graph[v]);
+            if(p[v] == v)
+                break;
+        }
+    }
+    return shortest_path;
+}
+
+PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid)
+{
+    PathGridGraph graph;
+
+    for(int i = 0;i<pathgrid->mPoints.size();i++)
+    {
+        PointID pID = boost::add_vertex(graph);
+        graph[pID] = pathgrid->mPoints[i];
+    }
+
+    for(int i = 0;i<pathgrid->mEdges.size();i++)
+    {
+        PointID u = pathgrid->mEdges[i].mV0;
+        PointID v = pathgrid->mEdges[i].mV1;
+
+        PointConnectionID edge;
+        bool done;
+        boost::tie(edge,done) = boost::add_edge(u,v,graph);
+        WeightMap weightmap = boost::get(boost::edge_weight, graph);
+        weightmap[edge] = distance(graph[u],graph[v]);
+
+    }
+
+    return graph;
+}
+
 bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
 {
-    std::cout << "AiTravel completed.\n";
-    return true;
+    const ESM::Pathgrid *pathgrid =
+        MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
+    
+    ESM::Position pos = actor.getRefData().getPosition();
+
+    if(!isPathConstructed)
+    {
+        int start = getClosestPoint(pathgrid,pos.pos[0],pos.pos[1],pos.pos[2]);
+        int end = getClosestPoint(pathgrid,mX,mY,mZ);
+
+        PathGridGraph graph = buildGraph(pathgrid);
+
+        mPath = getPath(start,end,graph);
+        isPathConstructed = true;
+    }
+    if(mPath.empty())
+    {
+        MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+        return true;
+    }
+    ESM::Pathgrid::Point nextPoint = *mPath.begin();
+    if(distance(nextPoint,pos.pos[0],pos.pos[1],pos.pos[2]) < 20)
+    {
+        mPath.pop_front();
+        if(mPath.empty())
+        {
+            MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+            return true;
+        }
+        nextPoint = *mPath.begin();
+    }
+    
+    float dX = nextPoint.mX - pos.pos[0];
+    float dY = nextPoint.mY - pos.pos[1];
+
+    MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,getZAngle(dX,dY),false);
+    MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 1;
+    return false;
+    //return true;
 }
 
 int MWMechanics::AiTravel::getTypeId() const
diff --git a/apps/openmw/mwmechanics/aitravel.hpp b/apps/openmw/mwmechanics/aitravel.hpp
index 1c6abbf279..a596f4c85d 100644
--- a/apps/openmw/mwmechanics/aitravel.hpp
+++ b/apps/openmw/mwmechanics/aitravel.hpp
@@ -1,7 +1,9 @@
 #ifndef GAME_MWMECHANICS_AITRAVEL_H
 #define GAME_MWMECHANICS_AITRAVEL_H
 
-#include "aipackage.hpp"
+#include "aipackage.hpp"
+#include "components\esm\loadpgrd.hpp"
+#include <list>
 
 namespace MWMechanics
 {
@@ -21,6 +23,9 @@ namespace MWMechanics
             float mY;
             float mZ;
 
+            bool isPathConstructed;
+            std::list<ESM::Pathgrid::Point> mPath;
+
     };
 }
 

From 01908dbcc27f2202e13dce90fe24f77dc268c97c Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Wed, 6 Mar 2013 21:17:33 +0000
Subject: [PATCH 02/15] little improvement

---
 apps/openmw/mwmechanics/aitravel.cpp | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index b5e67e449b..9d41a080c7 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -22,6 +22,11 @@ MWMechanics::AiTravel * MWMechanics::AiTravel::clone() const
     return new AiTravel(*this);
 }
 
+float distanceZCorrected(ESM::Pathgrid::Point point,float x,float y,float z)
+{
+    return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+0.1*(point.mZ - z)*(point.mZ - z));
+}
+
 float distance(ESM::Pathgrid::Point point,float x,float y,float z)
 {
     return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+(point.mZ - z)*(point.mZ - z));
@@ -64,11 +69,6 @@ float getZAngle(float dX,float dY)
     return Ogre::Radian(acos(dY/h)*sgn(asin(dX/h))).valueDegrees();
 }
 
-struct Edge
-{
-    float distance;
-};
-
 typedef boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,
     boost::property<boost::vertex_index_t,int,ESM::Pathgrid::Point>,boost::property<boost::edge_weight_t,float> > PathGridGraph;
 typedef boost::property_map<PathGridGraph, boost::edge_weight_t>::type WeightMap;
@@ -176,6 +176,11 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         PathGridGraph graph = buildGraph(pathgrid);
 
         mPath = getPath(start,end,graph);
+        ESM::Pathgrid::Point dest;
+        dest.mX = mX;
+        dest.mY = mY;
+        dest.mZ = mZ;
+        mPath.push_back(dest);
         isPathConstructed = true;
     }
     if(mPath.empty())
@@ -184,7 +189,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         return true;
     }
     ESM::Pathgrid::Point nextPoint = *mPath.begin();
-    if(distance(nextPoint,pos.pos[0],pos.pos[1],pos.pos[2]) < 20)
+    if(distanceZCorrected(nextPoint,pos.pos[0],pos.pos[1],pos.pos[2]) < 20)
     {
         mPath.pop_front();
         if(mPath.empty())

From bbc4c23f7e184782eec35bface3e0d10df182dd1 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Sun, 10 Mar 2013 15:07:22 +0000
Subject: [PATCH 03/15] AITravel now works correctly on exterior cells. As long
 as NPC don't try to leave cell, it's ok.

---
 apps/openmw/mwmechanics/aitravel.cpp | 31 ++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 9d41a080c7..09b0efad9c 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -53,7 +53,7 @@ int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
             i0 = i;
         }
     }
-
+    std::cout << "distance:: " << m << "\n";
     return i0;
 }
 
@@ -135,14 +135,16 @@ std::list<ESM::Pathgrid::Point> getPath(PointID start,PointID end,PathGridGraph
     return shortest_path;
 }
 
-PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid)
+PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid,float xCell = 0,float yCell = 0)
 {
     PathGridGraph graph;
 
     for(int i = 0;i<pathgrid->mPoints.size();i++)
     {
         PointID pID = boost::add_vertex(graph);
-        graph[pID] = pathgrid->mPoints[i];
+        graph[pID].mX = pathgrid->mPoints[i].mX + xCell;
+        graph[pID].mY = pathgrid->mPoints[i].mY + yCell;
+        graph[pID].mZ = pathgrid->mPoints[i].mZ;
     }
 
     for(int i = 0;i<pathgrid->mEdges.size();i++)
@@ -165,17 +167,26 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
 {
     const ESM::Pathgrid *pathgrid =
         MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
-    
-    ESM::Position pos = actor.getRefData().getPosition();
 
+    ESM::Position pos = actor.getRefData().getPosition();
+    //std::cout << "npcpos" << pos.pos[0] << pos.pos[1] <<pos.pos[2] <<"\n";
     if(!isPathConstructed)
     {
-        int start = getClosestPoint(pathgrid,pos.pos[0],pos.pos[1],pos.pos[2]);
-        int end = getClosestPoint(pathgrid,mX,mY,mZ);
+        float xCell = 0;
+        float yCell = 0;
+        if (actor.getCell()->mCell->isExterior())
+        {
+            xCell = actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE;
+            yCell = actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE;
+        }
 
-        PathGridGraph graph = buildGraph(pathgrid);
+        int start = getClosestPoint(pathgrid,pos.pos[0] - xCell,pos.pos[1] - yCell,pos.pos[2]);
+        int end = getClosestPoint(pathgrid,mX - xCell,mY - yCell,mZ);
+
+        PathGridGraph graph = buildGraph(pathgrid,xCell,yCell);
 
         mPath = getPath(start,end,graph);
+        if(mPath.empty()) std::cout << "graph doesn't find any way...";
         ESM::Pathgrid::Point dest;
         dest.mX = mX;
         dest.mY = mY;
@@ -185,6 +196,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
     }
     if(mPath.empty())
     {
+        std::cout << "pathc empty";
         MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
         return true;
     }
@@ -195,6 +207,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         if(mPath.empty())
         {
             MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+            std::cout << "emptypath!";
             return true;
         }
         nextPoint = *mPath.begin();
@@ -205,8 +218,8 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
 
     MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,getZAngle(dX,dY),false);
     MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 1;
+
     return false;
-    //return true;
 }
 
 int MWMechanics::AiTravel::getTypeId() const

From f943580138209a27497e0613ab6914f5194a3589 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Tue, 12 Mar 2013 17:44:22 +0000
Subject: [PATCH 04/15] Somehow manages to get from one cell to another, but
 this looks wrong... And I don't know how morrowind do it, because aitravel is
 completly buggy

---
 apps/openmw/mwmechanics/aitravel.cpp | 6 +++++-
 apps/openmw/mwmechanics/aitravel.hpp | 3 +++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 09b0efad9c..3c2e29743a 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -169,9 +169,13 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
 
     ESM::Position pos = actor.getRefData().getPosition();
+    bool cellChange = actor.getCell()->mCell->mData.mX != cellX || actor.getCell()->mCell->mData.mY != cellY;
+    if(cellChange) std::cout << "cellChanged! \n";
     //std::cout << "npcpos" << pos.pos[0] << pos.pos[1] <<pos.pos[2] <<"\n";
-    if(!isPathConstructed)
+    if(!isPathConstructed ||cellChange)
     {
+        cellX = actor.getCell()->mCell->mData.mX;
+        cellY = actor.getCell()->mCell->mData.mY;
         float xCell = 0;
         float yCell = 0;
         if (actor.getCell()->mCell->isExterior())
diff --git a/apps/openmw/mwmechanics/aitravel.hpp b/apps/openmw/mwmechanics/aitravel.hpp
index a596f4c85d..3d220cb7e3 100644
--- a/apps/openmw/mwmechanics/aitravel.hpp
+++ b/apps/openmw/mwmechanics/aitravel.hpp
@@ -23,6 +23,9 @@ namespace MWMechanics
             float mY;
             float mZ;
 
+            int cellX;
+            int cellY;
+
             bool isPathConstructed;
             std::list<ESM::Pathgrid::Point> mPath;
 

From 80804fac351fedcde4735753c7ae2db461a80628 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Thu, 14 Mar 2013 17:16:37 +0000
Subject: [PATCH 05/15] check if the NPC is close from a non loaded cell. If
 yes, AITravel is simply ended.

---
 apps/openmw/mwmechanics/aitravel.cpp | 31 +++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 3c2e29743a..57b9f66dde 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -7,6 +7,7 @@
 #include "../mwbase/world.hpp"
 #include "../mwbase/environment.hpp"
 #include "movement.hpp"
+#include "../mwworld/player.hpp"
 
 #include <boost/graph/astar_search.hpp>
 #include <boost/graph/adjacency_list.hpp>
@@ -167,13 +168,35 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
 {
     const ESM::Pathgrid *pathgrid =
         MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
-
+    
     ESM::Position pos = actor.getRefData().getPosition();
     bool cellChange = actor.getCell()->mCell->mData.mX != cellX || actor.getCell()->mCell->mData.mY != cellY;
-    if(cellChange) std::cout << "cellChanged! \n";
+
+    MWWorld::Ptr player = MWBase::Environment::get().getWorld()->getPlayer().getPlayer();
+    if(actor.getCell()->mCell->mData.mX != player.getCell()->mCell->mData.mX)
+    {
+        int sideX = sgn(actor.getCell()->mCell->mData.mX != player.getCell()->mCell->mData.mX);
+        //check if actor is near the border of an inactive cell. If so, disable aitravel.
+        if(sideX*(pos.pos[0] - actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE) > sideX*(ESM::Land::REAL_SIZE/2. - 2000)) 
+        {
+            MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+            return true;
+        }
+    }
+    if(actor.getCell()->mCell->mData.mY != player.getCell()->mCell->mData.mY)
+    {
+        int sideY = sgn(actor.getCell()->mCell->mData.mY != player.getCell()->mCell->mData.mY);
+        //check if actor is near the border of an inactive cell. If so, disable aitravel.
+        if(sideY*(pos.pos[1] - actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE) > sideY*(ESM::Land::REAL_SIZE/2. - 2000)) 
+        {
+            MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+            return true;
+        }
+    }
     //std::cout << "npcpos" << pos.pos[0] << pos.pos[1] <<pos.pos[2] <<"\n";
     if(!isPathConstructed ||cellChange)
     {
+        std::cout << "constructing path.... \n";
         cellX = actor.getCell()->mCell->mData.mX;
         cellY = actor.getCell()->mCell->mData.mY;
         float xCell = 0;
@@ -190,7 +213,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         PathGridGraph graph = buildGraph(pathgrid,xCell,yCell);
 
         mPath = getPath(start,end,graph);
-        if(mPath.empty()) std::cout << "graph doesn't find any way...";
+
         ESM::Pathgrid::Point dest;
         dest.mX = mX;
         dest.mY = mY;
@@ -200,7 +223,6 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
     }
     if(mPath.empty())
     {
-        std::cout << "pathc empty";
         MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
         return true;
     }
@@ -211,7 +233,6 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         if(mPath.empty())
         {
             MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
-            std::cout << "emptypath!";
             return true;
         }
         nextPoint = *mPath.begin();

From 9efb073617cf41f66f774c9453574594fbcf2870 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Thu, 14 Mar 2013 18:05:00 +0000
Subject: [PATCH 06/15] clean up + correct a bug

---
 apps/openmw/mwmechanics/aitravel.cpp | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 57b9f66dde..94f6fd8928 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -40,8 +40,8 @@ float distance(ESM::Pathgrid::Point a,ESM::Pathgrid::Point b)
 
 int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
 {
-    if(!grid) throw std::exception("NULL PathGrid!");
-    if(grid->mPoints.empty()) throw std::exception("empty PathGrid!");
+    if(!grid) return -1;
+    if(grid->mPoints.empty()) return -1;
 
     float m = distance(grid->mPoints[0],x,y,z);
     int i0 = 0;
@@ -54,7 +54,6 @@ int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
             i0 = i;
         }
     }
-    std::cout << "distance:: " << m << "\n";
     return i0;
 }
 
@@ -175,7 +174,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
     MWWorld::Ptr player = MWBase::Environment::get().getWorld()->getPlayer().getPlayer();
     if(actor.getCell()->mCell->mData.mX != player.getCell()->mCell->mData.mX)
     {
-        int sideX = sgn(actor.getCell()->mCell->mData.mX != player.getCell()->mCell->mData.mX);
+        int sideX = sgn(actor.getCell()->mCell->mData.mX - player.getCell()->mCell->mData.mX);
         //check if actor is near the border of an inactive cell. If so, disable aitravel.
         if(sideX*(pos.pos[0] - actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE) > sideX*(ESM::Land::REAL_SIZE/2. - 2000)) 
         {
@@ -185,7 +184,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
     }
     if(actor.getCell()->mCell->mData.mY != player.getCell()->mCell->mData.mY)
     {
-        int sideY = sgn(actor.getCell()->mCell->mData.mY != player.getCell()->mCell->mData.mY);
+        int sideY = sgn(actor.getCell()->mCell->mData.mY - player.getCell()->mCell->mData.mY);
         //check if actor is near the border of an inactive cell. If so, disable aitravel.
         if(sideY*(pos.pos[1] - actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE) > sideY*(ESM::Land::REAL_SIZE/2. - 2000)) 
         {
@@ -193,10 +192,9 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
             return true;
         }
     }
-    //std::cout << "npcpos" << pos.pos[0] << pos.pos[1] <<pos.pos[2] <<"\n";
+
     if(!isPathConstructed ||cellChange)
     {
-        std::cout << "constructing path.... \n";
         cellX = actor.getCell()->mCell->mData.mX;
         cellY = actor.getCell()->mCell->mData.mY;
         float xCell = 0;
@@ -210,9 +208,11 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         int start = getClosestPoint(pathgrid,pos.pos[0] - xCell,pos.pos[1] - yCell,pos.pos[2]);
         int end = getClosestPoint(pathgrid,mX - xCell,mY - yCell,mZ);
 
-        PathGridGraph graph = buildGraph(pathgrid,xCell,yCell);
-
-        mPath = getPath(start,end,graph);
+        if(start != -1 && end != -1)
+        {
+            PathGridGraph graph = buildGraph(pathgrid,xCell,yCell);
+            mPath = getPath(start,end,graph);
+        }
 
         ESM::Pathgrid::Point dest;
         dest.mX = mX;

From efe6a3ebeec495a213a75ed3c072d9d2eb1c8c95 Mon Sep 17 00:00:00 2001
From: scrawl <scrawl@baseoftrash.de>
Date: Tue, 26 Mar 2013 18:01:01 +0100
Subject: [PATCH 07/15] Fix compile error & warnings

---
 apps/openmw/mwmechanics/aitravel.cpp |  6 +--
 apps/openmw/mwmechanics/aitravel.hpp | 60 ++++++++++++++--------------
 2 files changed, 33 insertions(+), 33 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 94f6fd8928..2c5260a625 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -46,7 +46,7 @@ int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
     float m = distance(grid->mPoints[0],x,y,z);
     int i0 = 0;
 
-    for(int i=1; i<grid->mPoints.size();i++)
+    for(unsigned int i=1; i<grid->mPoints.size();++i)
     {
         if(distance(grid->mPoints[i],x,y,z)<m)
         {
@@ -139,7 +139,7 @@ PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid,float xCell = 0,float yCe
 {
     PathGridGraph graph;
 
-    for(int i = 0;i<pathgrid->mPoints.size();i++)
+    for(unsigned int i = 0;i<pathgrid->mPoints.size();++i)
     {
         PointID pID = boost::add_vertex(graph);
         graph[pID].mX = pathgrid->mPoints[i].mX + xCell;
@@ -147,7 +147,7 @@ PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid,float xCell = 0,float yCe
         graph[pID].mZ = pathgrid->mPoints[i].mZ;
     }
 
-    for(int i = 0;i<pathgrid->mEdges.size();i++)
+    for(unsigned int i = 0;i<pathgrid->mEdges.size();++i)
     {
         PointID u = pathgrid->mEdges[i].mV0;
         PointID v = pathgrid->mEdges[i].mV1;
diff --git a/apps/openmw/mwmechanics/aitravel.hpp b/apps/openmw/mwmechanics/aitravel.hpp
index 3d220cb7e3..ef2359ba91 100644
--- a/apps/openmw/mwmechanics/aitravel.hpp
+++ b/apps/openmw/mwmechanics/aitravel.hpp
@@ -1,35 +1,35 @@
 #ifndef GAME_MWMECHANICS_AITRAVEL_H
 #define GAME_MWMECHANICS_AITRAVEL_H
-
-#include "aipackage.hpp"
-#include "components\esm\loadpgrd.hpp"
-#include <list>
-
-namespace MWMechanics
-{
-    class AiTravel : public AiPackage
-    {
-        public:
-            AiTravel(float x, float y, float z);
-            virtual AiTravel *clone() const;
-
-            virtual bool execute (const MWWorld::Ptr& actor);
-                    ///< \return Package completed?
-
-            virtual int getTypeId() const;
-
-        private:
-            float mX;
-            float mY;
-            float mZ;
-
-            int cellX;
-            int cellY;
-
-            bool isPathConstructed;
-            std::list<ESM::Pathgrid::Point> mPath;
-
-    };
+
+#include "aipackage.hpp"
+#include <components/esm/loadpgrd.hpp>
+#include <list>
+
+namespace MWMechanics
+{
+    class AiTravel : public AiPackage
+    {
+        public:
+            AiTravel(float x, float y, float z);
+            virtual AiTravel *clone() const;
+
+            virtual bool execute (const MWWorld::Ptr& actor);
+                    ///< \return Package completed?
+
+            virtual int getTypeId() const;
+
+        private:
+            float mX;
+            float mY;
+            float mZ;
+
+            int cellX;
+            int cellY;
+
+            bool isPathConstructed;
+            std::list<ESM::Pathgrid::Point> mPath;
+
+    };
 }
 
 #endif

From 63424ade56fd9c7da96446d666e4c4e774f1c4c0 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Sun, 31 Mar 2013 17:30:03 +0000
Subject: [PATCH 08/15] refactoring

---
 apps/openmw/CMakeLists.txt              |   2 +-
 apps/openmw/mwmechanics/aitravel.cpp    | 177 ++-------------------
 apps/openmw/mwmechanics/aitravel.hpp    |   8 +-
 apps/openmw/mwmechanics/pathfinding.cpp | 201 ++++++++++++++++++++++++
 apps/openmw/mwmechanics/pathfinding.hpp |  26 +++
 5 files changed, 245 insertions(+), 169 deletions(-)
 create mode 100644 apps/openmw/mwmechanics/pathfinding.cpp
 create mode 100644 apps/openmw/mwmechanics/pathfinding.hpp

diff --git a/apps/openmw/CMakeLists.txt b/apps/openmw/CMakeLists.txt
index 41599b35db..d29e0ff2e7 100644
--- a/apps/openmw/CMakeLists.txt
+++ b/apps/openmw/CMakeLists.txt
@@ -65,7 +65,7 @@ add_openmw_dir (mwclass
 add_openmw_dir (mwmechanics
     mechanicsmanagerimp stat character creaturestats magiceffects movement actors activators
     drawstate spells activespells npcstats aipackage aisequence alchemy aiwander aitravel aifollow
-    aiescort aiactivate repair
+    aiescort aiactivate repair pathfinding
     )
 
 add_openmw_dir (mwbase
diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 2c5260a625..df6a38bb03 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -14,7 +14,7 @@
 #include "boost/tuple/tuple.hpp"
 
 MWMechanics::AiTravel::AiTravel(float x, float y, float z)
-: mX(x),mY(y),mZ(z),isPathConstructed(false)
+    : mX(x),mY(y),mZ(z),mPathFinder()
 {
 }
 
@@ -23,151 +23,17 @@ MWMechanics::AiTravel * MWMechanics::AiTravel::clone() const
     return new AiTravel(*this);
 }
 
-float distanceZCorrected(ESM::Pathgrid::Point point,float x,float y,float z)
-{
-    return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+0.1*(point.mZ - z)*(point.mZ - z));
-}
-
-float distance(ESM::Pathgrid::Point point,float x,float y,float z)
-{
-    return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+(point.mZ - z)*(point.mZ - z));
-}
-
-float distance(ESM::Pathgrid::Point a,ESM::Pathgrid::Point b)
-{
-    return sqrt(float(a.mX - b.mX)*(a.mX - b.mX)+(a.mY - b.mY)*(a.mY - b.mY)+(a.mZ - b.mZ)*(a.mZ - b.mZ));
-}
-
-int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
-{
-    if(!grid) return -1;
-    if(grid->mPoints.empty()) return -1;
-
-    float m = distance(grid->mPoints[0],x,y,z);
-    int i0 = 0;
-
-    for(unsigned int i=1; i<grid->mPoints.size();++i)
-    {
-        if(distance(grid->mPoints[i],x,y,z)<m)
-        {
-            m = distance(grid->mPoints[i],x,y,z);
-            i0 = i;
-        }
-    }
-    return i0;
-}
-
 float sgn(float a)
 {
     if(a>0) return 1.;
     else return -1.;
 }
 
-float getZAngle(float dX,float dY)
-{
-    float h = sqrt(dX*dX+dY*dY);
-    return Ogre::Radian(acos(dY/h)*sgn(asin(dX/h))).valueDegrees();
-}
-
-typedef boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,
-    boost::property<boost::vertex_index_t,int,ESM::Pathgrid::Point>,boost::property<boost::edge_weight_t,float> > PathGridGraph;
-typedef boost::property_map<PathGridGraph, boost::edge_weight_t>::type WeightMap;
-typedef PathGridGraph::vertex_descriptor PointID;
-typedef PathGridGraph::edge_descriptor   PointConnectionID;
-
-struct found_path {};
-
-class goalVisited : public boost::default_astar_visitor
-{
-public:
-    goalVisited(PointID goal) : mGoal(goal) {}
-    
-    void examine_vertex(PointID u, const PathGridGraph g)
-    {
-        if(u == mGoal)
-            throw found_path();
-    }
-private:
-    PointID mGoal;
-};
-
-class DistanceHeuristic : public boost::astar_heuristic <PathGridGraph, float>
-{
-public:
-    DistanceHeuristic(const PathGridGraph & l, PointID goal)
-    : mGraph(l), mGoal(goal) {}
- 
-    float operator()(PointID u)
-    {
-        const ESM::Pathgrid::Point & U = mGraph[u];
-        const ESM::Pathgrid::Point & V = mGraph[mGoal];
-        float dx = U.mX - V.mX;
-        float dy = U.mY - V.mY;
-        float dz = U.mZ - V.mZ;
-        return sqrt(dx * dx + dy * dy + dz * dz);
-    }
-private:
-    const PathGridGraph & mGraph;
-    PointID mGoal;
-};
-
-std::list<ESM::Pathgrid::Point> getPath(PointID start,PointID end,PathGridGraph graph){
-    std::vector<PointID> p(boost::num_vertices(graph));
-    std::vector<float> d(boost::num_vertices(graph));
-    std::list<ESM::Pathgrid::Point> shortest_path;
-
-    try {
-        boost::astar_search
-            (
-            graph,
-            start,
-            DistanceHeuristic(graph,end),
-            boost::predecessor_map(&p[0]).distance_map(&d[0]).visitor(goalVisited(end))//.weight_map(boost::get(&Edge::distance, graph))
-            );
-
-    } catch(found_path fg) {
-        for(PointID v = end;; v = p[v]) {
-            shortest_path.push_front(graph[v]);
-            if(p[v] == v)
-                break;
-        }
-    }
-    return shortest_path;
-}
-
-PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid,float xCell = 0,float yCell = 0)
-{
-    PathGridGraph graph;
-
-    for(unsigned int i = 0;i<pathgrid->mPoints.size();++i)
-    {
-        PointID pID = boost::add_vertex(graph);
-        graph[pID].mX = pathgrid->mPoints[i].mX + xCell;
-        graph[pID].mY = pathgrid->mPoints[i].mY + yCell;
-        graph[pID].mZ = pathgrid->mPoints[i].mZ;
-    }
-
-    for(unsigned int i = 0;i<pathgrid->mEdges.size();++i)
-    {
-        PointID u = pathgrid->mEdges[i].mV0;
-        PointID v = pathgrid->mEdges[i].mV1;
-
-        PointConnectionID edge;
-        bool done;
-        boost::tie(edge,done) = boost::add_edge(u,v,graph);
-        WeightMap weightmap = boost::get(boost::edge_weight, graph);
-        weightmap[edge] = distance(graph[u],graph[v]);
-
-    }
-
-    return graph;
-}
-
 bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
 {
     const ESM::Pathgrid *pathgrid =
         MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
-    
+
     ESM::Position pos = actor.getRefData().getPosition();
     bool cellChange = actor.getCell()->mCell->mData.mX != cellX || actor.getCell()->mCell->mData.mY != cellY;
 
@@ -193,7 +59,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         }
     }
 
-    if(!isPathConstructed ||cellChange)
+    if(!mPathFinder.mIsPathConstructed ||cellChange)
     {
         cellX = actor.getCell()->mCell->mData.mX;
         cellY = actor.getCell()->mCell->mData.mY;
@@ -205,43 +71,26 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
             yCell = actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE;
         }
 
-        int start = getClosestPoint(pathgrid,pos.pos[0] - xCell,pos.pos[1] - yCell,pos.pos[2]);
-        int end = getClosestPoint(pathgrid,mX - xCell,mY - yCell,mZ);
-
-        if(start != -1 && end != -1)
-        {
-            PathGridGraph graph = buildGraph(pathgrid,xCell,yCell);
-            mPath = getPath(start,end,graph);
-        }
-
         ESM::Pathgrid::Point dest;
         dest.mX = mX;
         dest.mY = mY;
         dest.mZ = mZ;
-        mPath.push_back(dest);
-        isPathConstructed = true;
+
+        ESM::Pathgrid::Point start;
+        dest.mX = pos.pos[0];
+        dest.mY = pos.pos[1];
+        dest.mZ = pos.pos[2];
+
+        mPathFinder.findPath(start,dest,pathgrid,xCell,yCell);
     }
-    if(mPath.empty())
+    if(mPathFinder.checkIfNextPointReached(pos.pos[0],pos.pos[1],pos.pos[2]))
     {
         MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
         return true;
     }
-    ESM::Pathgrid::Point nextPoint = *mPath.begin();
-    if(distanceZCorrected(nextPoint,pos.pos[0],pos.pos[1],pos.pos[2]) < 20)
-    {
-        mPath.pop_front();
-        if(mPath.empty())
-        {
-            MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
-            return true;
-        }
-        nextPoint = *mPath.begin();
-    }
-    
-    float dX = nextPoint.mX - pos.pos[0];
-    float dY = nextPoint.mY - pos.pos[1];
 
-    MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,getZAngle(dX,dY),false);
+    float zAngle = mPathFinder.getZAngleToNext(pos.pos[0],pos.pos[1],pos.pos[2]);
+    MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,zAngle,false);
     MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 1;
 
     return false;
diff --git a/apps/openmw/mwmechanics/aitravel.hpp b/apps/openmw/mwmechanics/aitravel.hpp
index ef2359ba91..52b41850f1 100644
--- a/apps/openmw/mwmechanics/aitravel.hpp
+++ b/apps/openmw/mwmechanics/aitravel.hpp
@@ -2,8 +2,7 @@
 #define GAME_MWMECHANICS_AITRAVEL_H
 
 #include "aipackage.hpp"
-#include <components/esm/loadpgrd.hpp>
-#include <list>
+#include "pathfinding.hpp"
 
 namespace MWMechanics
 {
@@ -26,8 +25,9 @@ namespace MWMechanics
             int cellX;
             int cellY;
 
-            bool isPathConstructed;
-            std::list<ESM::Pathgrid::Point> mPath;
+            //bool isPathConstructed;
+            //std::list<ESM::Pathgrid::Point> mPath;
+            PathFinder mPathFinder;
 
     };
 }
diff --git a/apps/openmw/mwmechanics/pathfinding.cpp b/apps/openmw/mwmechanics/pathfinding.cpp
new file mode 100644
index 0000000000..9b76082b48
--- /dev/null
+++ b/apps/openmw/mwmechanics/pathfinding.cpp
@@ -0,0 +1,201 @@
+#include "pathfinding.hpp"
+#include <boost/graph/astar_search.hpp>
+#include <boost/graph/adjacency_list.hpp>
+#include "boost/tuple/tuple.hpp"
+#include "OgreMath.h"
+
+namespace MWMechanics
+{
+
+    //helpers functions
+    float distanceZCorrected(ESM::Pathgrid::Point point,float x,float y,float z)
+    {
+        return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+0.1*(point.mZ - z)*(point.mZ - z));
+    }
+
+    float distance(ESM::Pathgrid::Point point,float x,float y,float z)
+    {
+        return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+(point.mZ - z)*(point.mZ - z));
+    }
+
+    float distance(ESM::Pathgrid::Point a,ESM::Pathgrid::Point b)
+    {
+        return sqrt(float(a.mX - b.mX)*(a.mX - b.mX)+(a.mY - b.mY)*(a.mY - b.mY)+(a.mZ - b.mZ)*(a.mZ - b.mZ));
+    }
+
+    float sgn(float a)
+    {
+        if(a>0) return 1.;
+        else return -1.;
+    }
+
+    int getClosestPoint(const ESM::Pathgrid* grid,float x,float y,float z)
+    {
+        if(!grid) return -1;
+        if(grid->mPoints.empty()) return -1;
+
+        float m = distance(grid->mPoints[0],x,y,z);
+        int i0 = 0;
+
+        for(unsigned int i=1; i<grid->mPoints.size();++i)
+        {
+            if(distance(grid->mPoints[i],x,y,z)<m)
+            {
+                m = distance(grid->mPoints[i],x,y,z);
+                i0 = i;
+            }
+        }
+        return i0;
+    }
+
+    typedef boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,
+        boost::property<boost::vertex_index_t,int,ESM::Pathgrid::Point>,boost::property<boost::edge_weight_t,float> > PathGridGraph;
+    typedef boost::property_map<PathGridGraph, boost::edge_weight_t>::type WeightMap;
+    typedef PathGridGraph::vertex_descriptor PointID;
+    typedef PathGridGraph::edge_descriptor   PointConnectionID;
+
+    struct found_path {};
+
+    class goalVisited : public boost::default_astar_visitor
+    {
+    public:
+        goalVisited(PointID goal) : mGoal(goal) {}
+
+        void examine_vertex(PointID u, const PathGridGraph g)
+        {
+            if(u == mGoal)
+                throw found_path();
+        }
+    private:
+        PointID mGoal;
+    };
+
+    class DistanceHeuristic : public boost::astar_heuristic <PathGridGraph, float>
+    {
+    public:
+        DistanceHeuristic(const PathGridGraph & l, PointID goal)
+            : mGraph(l), mGoal(goal) {}
+
+        float operator()(PointID u)
+        {
+            const ESM::Pathgrid::Point & U = mGraph[u];
+            const ESM::Pathgrid::Point & V = mGraph[mGoal];
+            float dx = U.mX - V.mX;
+            float dy = U.mY - V.mY;
+            float dz = U.mZ - V.mZ;
+            return sqrt(dx * dx + dy * dy + dz * dz);
+        }
+    private:
+        const PathGridGraph & mGraph;
+        PointID mGoal;
+    };
+
+    PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid,float xCell = 0,float yCell = 0)
+    {
+        PathGridGraph graph;
+
+        for(unsigned int i = 0;i<pathgrid->mPoints.size();++i)
+        {
+            PointID pID = boost::add_vertex(graph);
+            graph[pID].mX = pathgrid->mPoints[i].mX + xCell;
+            graph[pID].mY = pathgrid->mPoints[i].mY + yCell;
+            graph[pID].mZ = pathgrid->mPoints[i].mZ;
+        }
+
+        for(unsigned int i = 0;i<pathgrid->mEdges.size();++i)
+        {
+            PointID u = pathgrid->mEdges[i].mV0;
+            PointID v = pathgrid->mEdges[i].mV1;
+
+            PointConnectionID edge;
+            bool done;
+            boost::tie(edge,done) = boost::add_edge(u,v,graph);
+            WeightMap weightmap = boost::get(boost::edge_weight, graph);
+            weightmap[edge] = distance(graph[u],graph[v]);
+
+        }
+
+        return graph;
+    }
+
+    std::list<ESM::Pathgrid::Point> getPath(PointID start,PointID end,PathGridGraph graph){
+        std::vector<PointID> p(boost::num_vertices(graph));
+        std::vector<float> d(boost::num_vertices(graph));
+        std::list<ESM::Pathgrid::Point> shortest_path;
+
+        try {
+            boost::astar_search
+                (
+                graph,
+                start,
+                DistanceHeuristic(graph,end),
+                boost::predecessor_map(&p[0]).distance_map(&d[0]).visitor(goalVisited(end))//.weight_map(boost::get(&Edge::distance, graph))
+                );
+
+        } catch(found_path fg) {
+            for(PointID v = end;; v = p[v]) {
+                shortest_path.push_front(graph[v]);
+                if(p[v] == v)
+                    break;
+            }
+        }
+        return shortest_path;
+    }
+
+    //end of helpers functions
+
+    PathFinder::PathFinder()
+    {
+        mIsPathConstructed = false;
+    }
+
+    std::list<ESM::Pathgrid::Point> PathFinder::findPath(ESM::Pathgrid::Point startPoint,ESM::Pathgrid::Point endPoint,
+        const ESM::Pathgrid* pathGrid,float xCell,float yCell)
+    {
+        int start = getClosestPoint(pathGrid,startPoint.mX - xCell,startPoint.mY - yCell,startPoint.mZ);
+        int end = getClosestPoint(pathGrid,endPoint.mX - xCell,endPoint.mY - yCell,endPoint.mZ);
+
+        if(start != -1 && end != -1)
+        {
+            PathGridGraph graph = buildGraph(pathGrid,xCell,yCell);
+            mPath = getPath(start,end,graph);
+        }
+
+        mPath.push_back(endPoint);
+        mIsPathConstructed = true;
+
+        return mPath;
+    }
+
+    float PathFinder::getZAngleToNext(float x,float y,float z)
+    {
+        if(mPath.empty())
+        {
+            return 0;/// shouldn't happen!
+        }
+        ESM::Pathgrid::Point nextPoint = *mPath.begin();
+        float dX = nextPoint.mX - x;
+        float dY = nextPoint.mY - y;
+        float h = sqrt(dX*dX+dY*dY);
+        return Ogre::Radian(acos(dY/h)*sgn(asin(dX/h))).valueDegrees();
+    }
+
+    bool PathFinder::checkIfNextPointReached(float x,float y,float z)
+    {
+        if(mPath.empty())
+        {
+            return true;
+        }
+        ESM::Pathgrid::Point nextPoint = *mPath.begin();
+        if(distanceZCorrected(nextPoint,x,y,z) < 20)
+        {
+            mPath.pop_front();
+            if(mPath.empty())
+            {
+                return true;
+            }
+            nextPoint = *mPath.begin();
+        }
+        return false;
+    }
+}
\ No newline at end of file
diff --git a/apps/openmw/mwmechanics/pathfinding.hpp b/apps/openmw/mwmechanics/pathfinding.hpp
new file mode 100644
index 0000000000..200b191259
--- /dev/null
+++ b/apps/openmw/mwmechanics/pathfinding.hpp
@@ -0,0 +1,26 @@
+#ifndef GAME_MWMECHANICS_PATHFINDING_H
+#define GAME_MWMECHANICS_PATHFINDING_H
+
+#include <components/esm/loadpgrd.hpp>
+#include <list>
+
+namespace MWMechanics
+{
+    class PathFinder
+    {
+    public:
+        PathFinder();
+
+        std::list<ESM::Pathgrid::Point> findPath(ESM::Pathgrid::Point startPoint,ESM::Pathgrid::Point endPoint,
+            const ESM::Pathgrid* pathGrid,float xCell = 0,float yCell = 0);
+
+        bool checkIfNextPointReached(float x,float y,float z);//returns true if the last point of the path has been reached.
+        float getZAngleToNext(float x,float y,float z);
+
+
+        std::list<ESM::Pathgrid::Point> mPath;
+        bool mIsPathConstructed;
+    };
+}
+
+#endif
\ No newline at end of file

From 47cc945ef47e646e29a2f49d997ec8b0ba274fd4 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Mon, 1 Apr 2013 12:38:13 +0000
Subject: [PATCH 09/15] more refactoring

---
 apps/openmw/mwmechanics/aitravel.cpp    |  4 ++--
 apps/openmw/mwmechanics/pathfinding.cpp | 17 ++++++++++++-----
 apps/openmw/mwmechanics/pathfinding.hpp |  5 ++++-
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index df6a38bb03..b1a4cd0a69 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -59,7 +59,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         }
     }
 
-    if(!mPathFinder.mIsPathConstructed ||cellChange)
+    if(!mPathFinder.isPathConstructed() ||cellChange)
     {
         cellX = actor.getCell()->mCell->mData.mX;
         cellY = actor.getCell()->mCell->mData.mY;
@@ -81,7 +81,7 @@ bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
         dest.mY = pos.pos[1];
         dest.mZ = pos.pos[2];
 
-        mPathFinder.findPath(start,dest,pathgrid,xCell,yCell);
+        mPathFinder.buildPath(start,dest,pathgrid,xCell,yCell);
     }
     if(mPathFinder.checkIfNextPointReached(pos.pos[0],pos.pos[1],pos.pos[2]))
     {
diff --git a/apps/openmw/mwmechanics/pathfinding.cpp b/apps/openmw/mwmechanics/pathfinding.cpp
index 9b76082b48..fdac50ddac 100644
--- a/apps/openmw/mwmechanics/pathfinding.cpp
+++ b/apps/openmw/mwmechanics/pathfinding.cpp
@@ -118,7 +118,7 @@ namespace MWMechanics
         return graph;
     }
 
-    std::list<ESM::Pathgrid::Point> getPath(PointID start,PointID end,PathGridGraph graph){
+    std::list<ESM::Pathgrid::Point> findPath(PointID start,PointID end,PathGridGraph graph){
         std::vector<PointID> p(boost::num_vertices(graph));
         std::vector<float> d(boost::num_vertices(graph));
         std::list<ESM::Pathgrid::Point> shortest_path;
@@ -149,7 +149,7 @@ namespace MWMechanics
         mIsPathConstructed = false;
     }
 
-    std::list<ESM::Pathgrid::Point> PathFinder::findPath(ESM::Pathgrid::Point startPoint,ESM::Pathgrid::Point endPoint,
+    void PathFinder::buildPath(ESM::Pathgrid::Point startPoint,ESM::Pathgrid::Point endPoint,
         const ESM::Pathgrid* pathGrid,float xCell,float yCell)
     {
         int start = getClosestPoint(pathGrid,startPoint.mX - xCell,startPoint.mY - yCell,startPoint.mZ);
@@ -158,13 +158,11 @@ namespace MWMechanics
         if(start != -1 && end != -1)
         {
             PathGridGraph graph = buildGraph(pathGrid,xCell,yCell);
-            mPath = getPath(start,end,graph);
+            mPath = findPath(start,end,graph);
         }
 
         mPath.push_back(endPoint);
         mIsPathConstructed = true;
-
-        return mPath;
     }
 
     float PathFinder::getZAngleToNext(float x,float y,float z)
@@ -198,4 +196,13 @@ namespace MWMechanics
         }
         return false;
     }
+
+    std::list<ESM::Pathgrid::Point> PathFinder::getPath()
+    {
+        return mPath;
+    }
+    bool PathFinder::isPathConstructed()
+    {
+        return mIsPathConstructed;
+    }
 }
\ No newline at end of file
diff --git a/apps/openmw/mwmechanics/pathfinding.hpp b/apps/openmw/mwmechanics/pathfinding.hpp
index 200b191259..b1bbab37ab 100644
--- a/apps/openmw/mwmechanics/pathfinding.hpp
+++ b/apps/openmw/mwmechanics/pathfinding.hpp
@@ -11,13 +11,16 @@ namespace MWMechanics
     public:
         PathFinder();
 
-        std::list<ESM::Pathgrid::Point> findPath(ESM::Pathgrid::Point startPoint,ESM::Pathgrid::Point endPoint,
+        void buildPath(ESM::Pathgrid::Point startPoint,ESM::Pathgrid::Point endPoint,
             const ESM::Pathgrid* pathGrid,float xCell = 0,float yCell = 0);
 
         bool checkIfNextPointReached(float x,float y,float z);//returns true if the last point of the path has been reached.
         float getZAngleToNext(float x,float y,float z);
 
+        std::list<ESM::Pathgrid::Point> getPath();
+        bool isPathConstructed();
 
+    private:
         std::list<ESM::Pathgrid::Point> mPath;
         bool mIsPathConstructed;
     };

From 2be9405c96056fc6a12b2c5d4d048e0d74ca3d6d Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Mon, 1 Apr 2013 15:44:08 +0000
Subject: [PATCH 10/15] the sgn function is no longer in the global namespace

---
 apps/openmw/mwmechanics/aitravel.cpp | 157 ++++++++++++++-------------
 1 file changed, 80 insertions(+), 77 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index b1a4cd0a69..4aca5f3d49 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -13,92 +13,95 @@
 #include <boost/graph/adjacency_list.hpp>
 #include "boost/tuple/tuple.hpp"
 
-MWMechanics::AiTravel::AiTravel(float x, float y, float z)
-    : mX(x),mY(y),mZ(z),mPathFinder()
+namespace MWMechanics
 {
-}
 
-MWMechanics::AiTravel * MWMechanics::AiTravel::clone() const
-{
-    return new AiTravel(*this);
-}
-
-float sgn(float a)
-{
-    if(a>0) return 1.;
-    else return -1.;
-}
-
-bool MWMechanics::AiTravel::execute (const MWWorld::Ptr& actor)
-{
-    const ESM::Pathgrid *pathgrid =
-        MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
-
-    ESM::Position pos = actor.getRefData().getPosition();
-    bool cellChange = actor.getCell()->mCell->mData.mX != cellX || actor.getCell()->mCell->mData.mY != cellY;
-
-    MWWorld::Ptr player = MWBase::Environment::get().getWorld()->getPlayer().getPlayer();
-    if(actor.getCell()->mCell->mData.mX != player.getCell()->mCell->mData.mX)
+    AiTravel::AiTravel(float x, float y, float z)
+        : mX(x),mY(y),mZ(z),mPathFinder()
     {
-        int sideX = sgn(actor.getCell()->mCell->mData.mX - player.getCell()->mCell->mData.mX);
-        //check if actor is near the border of an inactive cell. If so, disable aitravel.
-        if(sideX*(pos.pos[0] - actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE) > sideX*(ESM::Land::REAL_SIZE/2. - 2000)) 
+    }
+
+    AiTravel * AiTravel::clone() const
+    {
+        return new AiTravel(*this);
+    }
+
+    float sgn(float a)
+    {
+        if(a>0) return 1.;
+        else return -1.;
+    }
+
+    bool AiTravel::execute (const MWWorld::Ptr& actor)
+    {
+        const ESM::Pathgrid *pathgrid =
+            MWBase::Environment::get().getWorld()->getStore().get<ESM::Pathgrid>().search(*actor.getCell()->mCell);
+
+        ESM::Position pos = actor.getRefData().getPosition();
+        bool cellChange = actor.getCell()->mCell->mData.mX != cellX || actor.getCell()->mCell->mData.mY != cellY;
+
+        MWWorld::Ptr player = MWBase::Environment::get().getWorld()->getPlayer().getPlayer();
+        if(actor.getCell()->mCell->mData.mX != player.getCell()->mCell->mData.mX)
+        {
+            int sideX = sgn(actor.getCell()->mCell->mData.mX - player.getCell()->mCell->mData.mX);
+            //check if actor is near the border of an inactive cell. If so, disable aitravel.
+            if(sideX*(pos.pos[0] - actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE) > sideX*(ESM::Land::REAL_SIZE/2. - 2000)) 
+            {
+                MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+                return true;
+            }
+        }
+        if(actor.getCell()->mCell->mData.mY != player.getCell()->mCell->mData.mY)
+        {
+            int sideY = sgn(actor.getCell()->mCell->mData.mY - player.getCell()->mCell->mData.mY);
+            //check if actor is near the border of an inactive cell. If so, disable aitravel.
+            if(sideY*(pos.pos[1] - actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE) > sideY*(ESM::Land::REAL_SIZE/2. - 2000)) 
+            {
+                MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+                return true;
+            }
+        }
+
+        if(!mPathFinder.isPathConstructed() ||cellChange)
+        {
+            cellX = actor.getCell()->mCell->mData.mX;
+            cellY = actor.getCell()->mCell->mData.mY;
+            float xCell = 0;
+            float yCell = 0;
+            if (actor.getCell()->mCell->isExterior())
+            {
+                xCell = actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE;
+                yCell = actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE;
+            }
+
+            ESM::Pathgrid::Point dest;
+            dest.mX = mX;
+            dest.mY = mY;
+            dest.mZ = mZ;
+
+            ESM::Pathgrid::Point start;
+            dest.mX = pos.pos[0];
+            dest.mY = pos.pos[1];
+            dest.mZ = pos.pos[2];
+
+            mPathFinder.buildPath(start,dest,pathgrid,xCell,yCell);
+        }
+        if(mPathFinder.checkIfNextPointReached(pos.pos[0],pos.pos[1],pos.pos[2]))
         {
             MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
             return true;
         }
+
+        float zAngle = mPathFinder.getZAngleToNext(pos.pos[0],pos.pos[1],pos.pos[2]);
+        MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,zAngle,false);
+        MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 1;
+
+        return false;
     }
-    if(actor.getCell()->mCell->mData.mY != player.getCell()->mCell->mData.mY)
+
+    int AiTravel::getTypeId() const
     {
-        int sideY = sgn(actor.getCell()->mCell->mData.mY - player.getCell()->mCell->mData.mY);
-        //check if actor is near the border of an inactive cell. If so, disable aitravel.
-        if(sideY*(pos.pos[1] - actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE) > sideY*(ESM::Land::REAL_SIZE/2. - 2000)) 
-        {
-            MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
-            return true;
-        }
+        return 1;
     }
 
-    if(!mPathFinder.isPathConstructed() ||cellChange)
-    {
-        cellX = actor.getCell()->mCell->mData.mX;
-        cellY = actor.getCell()->mCell->mData.mY;
-        float xCell = 0;
-        float yCell = 0;
-        if (actor.getCell()->mCell->isExterior())
-        {
-            xCell = actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE;
-            yCell = actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE;
-        }
-
-        ESM::Pathgrid::Point dest;
-        dest.mX = mX;
-        dest.mY = mY;
-        dest.mZ = mZ;
-
-        ESM::Pathgrid::Point start;
-        dest.mX = pos.pos[0];
-        dest.mY = pos.pos[1];
-        dest.mZ = pos.pos[2];
-
-        mPathFinder.buildPath(start,dest,pathgrid,xCell,yCell);
-    }
-    if(mPathFinder.checkIfNextPointReached(pos.pos[0],pos.pos[1],pos.pos[2]))
-    {
-        MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
-        return true;
-    }
-
-    float zAngle = mPathFinder.getZAngleToNext(pos.pos[0],pos.pos[1],pos.pos[2]);
-    MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,zAngle,false);
-    MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 1;
-
-    return false;
 }
-
-int MWMechanics::AiTravel::getTypeId() const
-{
-    return 1;
-}
-
-

From 20af7d89a2550a9873dd0ab03d5240af25f3b0f7 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Mon, 1 Apr 2013 17:30:40 +0000
Subject: [PATCH 11/15] post master-merge fixes. Looks a little odd.

---
 apps/openmw/mwmechanics/aitravel.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 4aca5f3d49..dd769f91c4 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -47,7 +47,7 @@ namespace MWMechanics
             //check if actor is near the border of an inactive cell. If so, disable aitravel.
             if(sideX*(pos.pos[0] - actor.getCell()->mCell->mData.mX * ESM::Land::REAL_SIZE) > sideX*(ESM::Land::REAL_SIZE/2. - 2000)) 
             {
-                MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+                MWWorld::Class::get(actor).getMovementSettings(actor).mPosition[1] = 0;
                 return true;
             }
         }
@@ -57,7 +57,7 @@ namespace MWMechanics
             //check if actor is near the border of an inactive cell. If so, disable aitravel.
             if(sideY*(pos.pos[1] - actor.getCell()->mCell->mData.mY * ESM::Land::REAL_SIZE) > sideY*(ESM::Land::REAL_SIZE/2. - 2000)) 
             {
-                MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+                MWWorld::Class::get(actor).getMovementSettings(actor).mPosition[1] = 0;
                 return true;
             }
         }
@@ -88,13 +88,13 @@ namespace MWMechanics
         }
         if(mPathFinder.checkIfNextPointReached(pos.pos[0],pos.pos[1],pos.pos[2]))
         {
-            MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 0;
+            MWWorld::Class::get(actor).getMovementSettings(actor).mPosition[1] = 0;
             return true;
         }
 
         float zAngle = mPathFinder.getZAngleToNext(pos.pos[0],pos.pos[1],pos.pos[2]);
         MWBase::Environment::get().getWorld()->rotateObject(actor,0,0,zAngle,false);
-        MWWorld::Class::get(actor).getMovementSettings(actor).mForwardBackward = 1;
+        MWWorld::Class::get(actor).getMovementSettings(actor).mPosition[1] = 1;
 
         return false;
     }

From 6a33170ca244db400d49651597ce3cc80d753723 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Mon, 1 Apr 2013 17:44:06 +0000
Subject: [PATCH 12/15] More bugfix, but I don't like this one.

---
 apps/openmw/mwmechanics/aitravel.cpp    | 2 +-
 apps/openmw/mwmechanics/pathfinding.cpp | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index dd769f91c4..25efe8fff0 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -26,7 +26,7 @@ namespace MWMechanics
         return new AiTravel(*this);
     }
 
-    float sgn(float a)
+    static float sgn(float a)
     {
         if(a>0) return 1.;
         else return -1.;
diff --git a/apps/openmw/mwmechanics/pathfinding.cpp b/apps/openmw/mwmechanics/pathfinding.cpp
index fdac50ddac..1d98674ef5 100644
--- a/apps/openmw/mwmechanics/pathfinding.cpp
+++ b/apps/openmw/mwmechanics/pathfinding.cpp
@@ -23,7 +23,7 @@ namespace MWMechanics
         return sqrt(float(a.mX - b.mX)*(a.mX - b.mX)+(a.mY - b.mY)*(a.mY - b.mY)+(a.mZ - b.mZ)*(a.mZ - b.mZ));
     }
 
-    float sgn(float a)
+    static float sgn(float a)
     {
         if(a>0) return 1.;
         else return -1.;

From 6934b20abd7c09ece9469f2be330512d91895982 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Thu, 11 Apr 2013 17:57:58 +0100
Subject: [PATCH 13/15] actors are now updates every frame. This should not be
 the case, but this is a quickfix for AI.

---
 apps/openmw/mwmechanics/actors.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apps/openmw/mwmechanics/actors.cpp b/apps/openmw/mwmechanics/actors.cpp
index 89671ee086..82e46ea463 100644
--- a/apps/openmw/mwmechanics/actors.cpp
+++ b/apps/openmw/mwmechanics/actors.cpp
@@ -210,7 +210,7 @@ namespace MWMechanics
     {
         mDuration += duration;
 
-        if (mDuration>=0.25)
+        //if (mDuration>=0.25)
         {
             float totalDuration = mDuration;
             mDuration = 0;

From 0a187e56aa8331624163789059dee3ca85a25095 Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Thu, 11 Apr 2013 17:58:11 +0100
Subject: [PATCH 14/15] bugfix

---
 apps/openmw/mwmechanics/aitravel.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 25efe8fff0..65d43749bc 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -80,9 +80,9 @@ namespace MWMechanics
             dest.mZ = mZ;
 
             ESM::Pathgrid::Point start;
-            dest.mX = pos.pos[0];
-            dest.mY = pos.pos[1];
-            dest.mZ = pos.pos[2];
+            start.mX = pos.pos[0];
+            start.mY = pos.pos[1];
+            start.mZ = pos.pos[2];
 
             mPathFinder.buildPath(start,dest,pathgrid,xCell,yCell);
         }

From 905cff2a9456406f1be91ca311ab219980e9840c Mon Sep 17 00:00:00 2001
From: gus <gus_512@hotmail.com>
Date: Thu, 11 Apr 2013 18:02:12 +0100
Subject: [PATCH 15/15] anonymous namespace

---
 apps/openmw/mwmechanics/aitravel.cpp    | 15 +++++++++------
 apps/openmw/mwmechanics/pathfinding.cpp |  8 +++++---
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/apps/openmw/mwmechanics/aitravel.cpp b/apps/openmw/mwmechanics/aitravel.cpp
index 65d43749bc..13ae2a592e 100644
--- a/apps/openmw/mwmechanics/aitravel.cpp
+++ b/apps/openmw/mwmechanics/aitravel.cpp
@@ -13,6 +13,15 @@
 #include <boost/graph/adjacency_list.hpp>
 #include "boost/tuple/tuple.hpp"
 
+namespace
+{
+    float sgn(float a)
+    {
+        if(a>0) return 1.;
+        else return -1.;
+    }
+}
+
 namespace MWMechanics
 {
 
@@ -26,12 +35,6 @@ namespace MWMechanics
         return new AiTravel(*this);
     }
 
-    static float sgn(float a)
-    {
-        if(a>0) return 1.;
-        else return -1.;
-    }
-
     bool AiTravel::execute (const MWWorld::Ptr& actor)
     {
         const ESM::Pathgrid *pathgrid =
diff --git a/apps/openmw/mwmechanics/pathfinding.cpp b/apps/openmw/mwmechanics/pathfinding.cpp
index 1d98674ef5..7c22e54701 100644
--- a/apps/openmw/mwmechanics/pathfinding.cpp
+++ b/apps/openmw/mwmechanics/pathfinding.cpp
@@ -4,10 +4,9 @@
 #include "boost/tuple/tuple.hpp"
 #include "OgreMath.h"
 
-namespace MWMechanics
+namespace
 {
-
-    //helpers functions
+	//helpers functions
     float distanceZCorrected(ESM::Pathgrid::Point point,float x,float y,float z)
     {
         return sqrt((point.mX - x)*(point.mX - x)+(point.mY - y)*(point.mY - y)+0.1*(point.mZ - z)*(point.mZ - z));
@@ -89,7 +88,10 @@ namespace MWMechanics
         const PathGridGraph & mGraph;
         PointID mGoal;
     };
+}
 
+namespace MWMechanics
+{
     PathGridGraph buildGraph(const ESM::Pathgrid* pathgrid,float xCell = 0,float yCell = 0)
     {
         PathGridGraph graph;