Chris@16: /*
Chris@16:     Copyright 2008 Intel Corporation
Chris@16:  
Chris@16:     Use, modification and distribution are subject to the Boost Software License,
Chris@16:     Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16:     http://www.boost.org/LICENSE_1_0.txt).
Chris@16: */
Chris@16: #include<iostream>
Chris@16: #include<cassert>
Chris@16: #ifndef BOOST_POLYGON_POLYGON_FORMATION_HPP
Chris@16: #define BOOST_POLYGON_POLYGON_FORMATION_HPP
Chris@16: namespace boost { namespace polygon{
Chris@16: 
Chris@16: namespace polygon_formation {
Chris@16: 
Chris@16:   /*
Chris@16:    * End has two states, HEAD and TAIL as is represented by a bool
Chris@16:    */
Chris@16:   typedef bool End;
Chris@16: 
Chris@16:   /*
Chris@16:    * HEAD End is represented as false because it is the lesser state
Chris@16:    */
Chris@16:   const End HEAD = false;
Chris@16: 
Chris@16:   /*
Chris@16:    * TAIL End is represented by true because TAIL comes after head and 1 after 0
Chris@16:    */
Chris@16:   const End TAIL = true;
Chris@16:    
Chris@16:   /*
Chris@16:    * 2D turning direction, left and right sides (is a boolean value since it has two states.)
Chris@16:    */
Chris@16:   typedef bool Side;
Chris@16:    
Chris@16:   /*
Chris@16:    * LEFT Side is 0 because we inuitively think left to right; left < right
Chris@16:    */
Chris@16:   const Side LEFT = false;
Chris@16:    
Chris@16:   /*
Chris@16:    * RIGHT Side is 1 so that right > left
Chris@16:    */
Chris@16:   const Side RIGHT = true;
Chris@16: 
Chris@16:   /*
Chris@16:    * The PolyLine class is data storage and services for building and representing partial polygons.  
Chris@16:    * As the polyline is added to it extends its storage to accomodate the data.
Chris@16:    * PolyLines can be joined head-to-head/head-to-tail when it is determined that two polylines are
Chris@16:    * part of the same polygon.
Chris@16:    * PolyLines keep state information about what orientation their incomplete head and tail geometry have,
Chris@16:    * which side of the polyline is solid and whether the polyline is joined head-to-head and tail-to-head.
Chris@16:    * PolyLines have nothing whatsoever to do with holes.
Chris@16:    * It may be valuable to collect a histogram of PolyLine lengths used by an algorithm on its typical data
Chris@16:    * sets and tune the allocation of the initial vector of coordinate data to be greater than or equal to
Chris@16:    * the mean, median, mode, or mean plus some number of standard deviation, or just generally large enough
Chris@16:    * to prevent too much unnecesary reallocations, but not too big that it wastes a lot of memory and degrades cache
Chris@16:    * performance.
Chris@16:    */
Chris@16:   template <typename Unit>
Chris@16:   class PolyLine {
Chris@16:   private:
Chris@16:     //data
Chris@16:      
Chris@16:     /*
Chris@16:      * ptdata_ a vector of coordiantes
Chris@16:      * if VERTICAL_HEAD, first coordiante is an X
Chris@16:      * else first coordinate is a Y
Chris@16:      */
Chris@16:     std::vector<Unit> ptdata_;
Chris@16:    
Chris@16:     /*
Chris@16:      * head and tail points to other polylines before and after this in a chain
Chris@16:      */
Chris@16:     PolyLine* headp_;
Chris@16:     PolyLine* tailp_;
Chris@16: 
Chris@16:     /*
Chris@16:      * state bitmask
Chris@16:      * bit zero is orientation, 0 H, 1 V
Chris@16:      * bit 1 is head connectivity, 0 for head, 1 for tail
Chris@16:      * bit 2 is tail connectivity, 0 for head, 1 for tail
Chris@16:      * bit 3 is solid to left of PolyLine when 1, right when 0
Chris@16:      */
Chris@16:     int state_;
Chris@16: 
Chris@16:   public:
Chris@16:     /*
Chris@16:      * default constructor (for preallocation)
Chris@16:      */
Chris@16:     PolyLine();
Chris@16:    
Chris@16:     /*
Chris@16:      * constructor that takes the orientation, coordiante and side to which there is solid
Chris@16:      */
Chris@16:     PolyLine(orientation_2d orient, Unit coord, Side side);
Chris@16:    
Chris@16:     //copy constructor
Chris@16:     PolyLine(const PolyLine& pline);
Chris@16:    
Chris@16:     //destructor
Chris@16:     ~PolyLine();
Chris@16:    
Chris@16:     //assignment operator
Chris@16:     PolyLine& operator=(const PolyLine& that);
Chris@16: 
Chris@16:     //equivalence operator
Chris@16:     bool operator==(const PolyLine& b) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * valid PolyLine (only default constructed polylines are invalid.)
Chris@16:      */
Chris@16:     bool isValid() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * Orientation of Head
Chris@16:      */
Chris@16:     orientation_2d headOrient() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * returns true if first coordinate is an X value (first segment is vertical)
Chris@16:      */
Chris@16:     bool verticalHead() const; 
Chris@16: 
Chris@16:     /*
Chris@16:      * returns the orientation_2d fo the tail
Chris@16:      */
Chris@16:     orientation_2d tailOrient() const;
Chris@16:       
Chris@16:     /*
Chris@16:      * returns true if last coordinate is an X value (last segment is vertical)
Chris@16:      */
Chris@16:     bool verticalTail() const;
Chris@16:      
Chris@16:     /*
Chris@16:      * retrun true if PolyLine has odd number of coordiantes
Chris@16:      */
Chris@16:     bool oddLength() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * retrun the End of the other polyline that the specified end of this polyline is connected to
Chris@16:      */
Chris@16:     End endConnectivity(End end) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * retrun true if the head of this polyline is connect to the tail of a polyline
Chris@16:      */
Chris@16:     bool headToTail() const;
Chris@16:     /*
Chris@16:      * retrun true if the head of this polyline is connect to the head of a polyline
Chris@16:      */
Chris@16:     bool headToHead() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * retrun true if the tail of this polyline is connect to the tail of a polyline
Chris@16:      */
Chris@16:     bool tailToTail() const;
Chris@16:     /*
Chris@16:      * retrun true if the tail of this polyline is connect to the head of a polyline
Chris@16:      */
Chris@16:     bool tailToHead() const;
Chris@16:      
Chris@16:     /*
Chris@16:      * retrun the side on which there is solid for this polyline
Chris@16:      */
Chris@16:     Side solidSide() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * retrun true if there is solid to the right of this polyline
Chris@16:      */
Chris@16:     bool solidToRight() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * returns true if the polyline tail is not connected
Chris@16:      */
Chris@16:     bool active() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * adds a coordinate value to the end of the polyline changing the tail orientation
Chris@16:      */
Chris@16:     PolyLine& pushCoordinate(Unit coord);
Chris@16:        
Chris@16:     /*
Chris@16:      * removes a coordinate value at the end of the polyline changing the tail orientation
Chris@16:      */
Chris@16:     PolyLine& popCoordinate();
Chris@16:       
Chris@16:     /*
Chris@16:      * extends the tail of the polyline to include the point, changing orientation if needed
Chris@16:      */
Chris@16:     PolyLine& pushPoint(const point_data<Unit>& point);
Chris@16: 
Chris@16:     /*
Chris@16:      * changes the last coordinate of the tail of the polyline by the amount of the delta
Chris@16:      */
Chris@16:     PolyLine& extendTail(Unit delta);
Chris@16: 
Chris@16:     /*
Chris@16:      * join thisEnd of this polyline to that polyline's end
Chris@16:      */
Chris@16:     PolyLine& joinTo(End thisEnd, PolyLine& that, End end);
Chris@16: 
Chris@16:     /*
Chris@16:      * join an end of this polyline to the tail of that polyline
Chris@16:      */
Chris@16:     PolyLine& joinToTail(PolyLine& that, End end);
Chris@16: 
Chris@16:     /*
Chris@16:      * join an end of this polyline to the head of that polyline
Chris@16:      */
Chris@16:     PolyLine& joinToHead(PolyLine& that, End end);
Chris@16: 
Chris@16:     /*
Chris@16:      * join the head of this polyline to the head of that polyline
Chris@16:      */
Chris@16:     //join this to that in the given way
Chris@16:     PolyLine& joinHeadToHead(PolyLine& that);
Chris@16: 
Chris@16:     /*
Chris@16:      * join the head of this polyline to the tail of that polyline
Chris@16:      */
Chris@16:     PolyLine& joinHeadToTail(PolyLine& that);
Chris@16: 
Chris@16:     /*
Chris@16:      * join the tail of this polyline to the head of that polyline
Chris@16:      */
Chris@16:     PolyLine& joinTailToHead(PolyLine& that);
Chris@16: 
Chris@16:     /*
Chris@16:      * join the tail of this polyline to the tail of that polyline
Chris@16:      */
Chris@16:     PolyLine& joinTailToTail(PolyLine& that);
Chris@16: 
Chris@16:     /*
Chris@16:      * dissconnect the tail at the end of the polygon
Chris@16:      */
Chris@16:     PolyLine& disconnectTails();
Chris@16: 
Chris@16:     /*
Chris@16:      * get the coordinate at one end of this polyline, by default the tail end
Chris@16:      */
Chris@16:     Unit getEndCoord(End end = TAIL) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the point on the polyline at the given index (polylines have the same number of coordinates as points
Chris@16:      */
Chris@16:     point_data<Unit> getPoint(unsigned int index) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the point on one end of the polyline, by default the tail
Chris@16:      */
Chris@16:     point_data<Unit> getEndPoint(End end = TAIL) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the orientation of a segment by index
Chris@16:      */
Chris@16:     orientation_2d segmentOrient(unsigned int index = 0) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get a coordinate by index using the square bracket operator
Chris@16:      */
Chris@16:     Unit operator[] (unsigned int index) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the number of segments/points/coordinates in the polyline
Chris@16:      */
Chris@16:     unsigned int numSegments() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the pointer to the next polyline at one end of this
Chris@16:      */
Chris@16:     PolyLine* next(End end) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * write out coordinates of this and all attached polylines to a single vector
Chris@16:      */
Chris@16:     PolyLine* writeOut(std::vector<Unit>& outVec, End startEnd = TAIL) const;
Chris@16: 
Chris@16:   private:
Chris@16:     //methods
Chris@16:     PolyLine& joinTo_(End thisEnd, PolyLine& that, End end);
Chris@16:   };
Chris@16: 
Chris@16:   //forward declaration
Chris@16:   template<bool orientT, typename Unit>
Chris@16:   class PolyLinePolygonData;
Chris@16: 
Chris@16:   //forward declaration
Chris@16:   template<bool orientT, typename Unit>
Chris@16:   class PolyLinePolygonWithHolesData;
Chris@16: 
Chris@16:   /*
Chris@16:    * ActiveTail represents an edge of an incomplete polygon.
Chris@16:    *
Chris@16:    * An ActiveTail object is the active tail end of a polyline object, which may (should) be the attached to
Chris@16:    * a chain of polyline objects through a pointer.  The ActiveTail class provides an abstraction between
Chris@16:    * and algorithm that builds polygons and the PolyLine data representation of incomplete polygons that are
Chris@16:    * being built.  It does this by providing an iterface to access the information about the last edge at the
Chris@16:    * tail of the PolyLine it is associated with.  To a polygon constructing algorithm, an ActiveTail is a floating
Chris@16:    * edge of an incomplete polygon and has an orientation and coordinate value, as well as knowing which side of
Chris@16:    * that edge is supposed to be solid or space.  Any incomplete polygon will have two active tails.  Active tails
Chris@16:    * may be joined together to merge two incomplete polygons into a larger incomplete polygon.  If two active tails
Chris@16:    * that are to be merged are the oppositve ends of the same incomplete polygon that indicates that the polygon
Chris@16:    * has been closed and is complete.  The active tail keeps a pointer to the other active tail of its incomplete 
Chris@16:    * polygon so that it is easy to check this condition.  These pointers are updated when active tails are joined.
Chris@16:    * The active tail also keeps a list of pointers to active tail objects that serve as handles to closed holes.  In
Chris@16:    * this way a hole can be associated to another incomplete polygon, which will eventually be its enclosing shell,
Chris@16:    * or reassociate the hole to another incomplete polygon in the case that it become a hole itself.  Alternately,
Chris@16:    * the active tail may add a filiment to stitch a hole into a shell and "fracture" the hole out of the interior
Chris@16:    * of a polygon.  The active tail maintains a static output buffer to temporarily write polygon data to when
Chris@16:    * it outputs a figure so that outputting a polygon does not require the allocation of a temporary buffer.  This
Chris@16:    * static buffer should be destroyed whenever the program determines that it won't need it anymore and would prefer to
Chris@16:    * release the memory it has allocated back to the system.
Chris@16:    */
Chris@16:   template <typename Unit>
Chris@16:   class ActiveTail {
Chris@16:   private:
Chris@16:     //data
Chris@16:     PolyLine<Unit>* tailp_; 
Chris@16:     ActiveTail *otherTailp_;
Chris@16:     std::list<ActiveTail*> holesList_;
Chris@16:     //Sum of all the polylines which constitute the active tail (including holes)//
Chris@16:     size_t polyLineSize_;  
Chris@16:   public:
Chris@16: 
Chris@16:     inline size_t getPolyLineSize(){
Chris@16:        return polyLineSize_;
Chris@16:     }
Chris@16: 
Chris@16:     inline void setPolyLineSize(int delta){
Chris@16:        polyLineSize_ = delta;
Chris@16:     }
Chris@16: 
Chris@16:     inline void addPolyLineSize(int delta){
Chris@16:        polyLineSize_ += delta;
Chris@16:     }
Chris@16:     
Chris@16:     /*
Chris@16:      * iterator over coordinates of the figure
Chris@16:      */
Chris@16:     class iterator {
Chris@16:     private:
Chris@16:       const PolyLine<Unit>* pLine_;
Chris@16:       const PolyLine<Unit>* pLineEnd_;
Chris@16:       unsigned int index_;
Chris@16:       unsigned int indexEnd_;
Chris@16:       End startEnd_;
Chris@16:     public:
Chris@16:       inline iterator() : pLine_(), pLineEnd_(), index_(), indexEnd_(), startEnd_() {}
Chris@16:       inline iterator(const ActiveTail* at, bool isHole, orientation_2d orient) : 
Chris@16:         pLine_(), pLineEnd_(), index_(), indexEnd_(), startEnd_() {
Chris@16:         //if it is a hole and orientation is vertical or it is not a hole and orientation is horizontal
Chris@16:         //we want to use this active tail, otherwise we want to use the other active tail
Chris@16:         startEnd_ = TAIL;
Chris@16:         if(!isHole ^ (orient == HORIZONTAL)) {
Chris@16:           //switch winding direction
Chris@16:           at = at->getOtherActiveTail();
Chris@16:         }
Chris@16:         //now we have the right winding direction
Chris@16:         //if it is horizontal we need to skip the first element
Chris@16:         pLine_ = at->getTail();
Chris@16: 
Chris@16:         if(at->getTail()->numSegments() > 0)
Chris@16:          index_ = at->getTail()->numSegments() - 1;
Chris@16: 
Chris@16:         if((at->getOrient() == HORIZONTAL) ^ (orient == HORIZONTAL)) {
Chris@16:           pLineEnd_ = at->getTail();
Chris@16:           indexEnd_ = pLineEnd_->numSegments() - 1;
Chris@16:           if(index_ == 0) {
Chris@16:             pLine_ = at->getTail()->next(HEAD);
Chris@16:             if(at->getTail()->endConnectivity(HEAD) == TAIL) {
Chris@16:               index_ = pLine_->numSegments() -1;
Chris@16:             } else {
Chris@16:               startEnd_ = HEAD;
Chris@16:               index_ = 0;
Chris@16:             }
Chris@16:           } else { --index_; }
Chris@16:         } else {
Chris@16:           pLineEnd_ = at->getOtherActiveTail()->getTail();
Chris@16:           if(pLineEnd_->numSegments() > 0)
Chris@16:           indexEnd_ = pLineEnd_->numSegments() - 1;
Chris@16:         }
Chris@16:         at->getTail()->joinTailToTail(*(at->getOtherActiveTail()->getTail()));
Chris@16:       }
Chris@16: 
Chris@16:       inline size_t size(void){
Chris@16:         size_t count = 0;
Chris@16:         End dir = startEnd_;
Chris@16:         PolyLine<Unit> const * currLine = pLine_;
Chris@16:         size_t ops = 0;
Chris@16:         while(currLine != pLineEnd_){
Chris@16:            ops++;
Chris@16:            count += currLine->numSegments();
Chris@16:            currLine = currLine->next(dir == HEAD ? TAIL : HEAD); 
Chris@16:            dir = currLine->endConnectivity(dir == HEAD ? TAIL : HEAD); 
Chris@16:         }
Chris@16:         count += pLineEnd_->numSegments();
Chris@16:         return count; //no. of vertices 
Chris@16:       }
Chris@16: 
Chris@16:       //use bitwise copy and assign provided by the compiler
Chris@16:       inline iterator& operator++() {
Chris@16:         if(pLine_ == pLineEnd_ && index_ == indexEnd_) {
Chris@16:           pLine_ = 0;
Chris@16:           index_ = 0;
Chris@16:           return *this;
Chris@16:         }
Chris@16:         if(startEnd_ == HEAD) {
Chris@16:           ++index_;
Chris@16:           if(index_ == pLine_->numSegments()) {
Chris@16:             End end = pLine_->endConnectivity(TAIL);
Chris@16:             pLine_ = pLine_->next(TAIL);
Chris@16:             if(end == TAIL) {
Chris@16:               startEnd_ = TAIL;
Chris@16:               index_ = pLine_->numSegments() -1;
Chris@16:             } else {
Chris@16:               index_ = 0;
Chris@16:             }
Chris@16:           }
Chris@16:         } else {
Chris@16:           if(index_ == 0) {
Chris@16:             End end = pLine_->endConnectivity(HEAD);
Chris@16:             pLine_ = pLine_->next(HEAD);
Chris@16:             if(end == TAIL) {
Chris@16:               index_ = pLine_->numSegments() -1;
Chris@16:             } else {
Chris@16:               startEnd_ = HEAD;
Chris@16:               index_ = 0;
Chris@16:             }
Chris@16:           } else {
Chris@16:             --index_;
Chris@16:           }
Chris@16:         }
Chris@16:         return *this;
Chris@16:       }
Chris@16:       inline const iterator operator++(int) {
Chris@16:         iterator tmp(*this);
Chris@16:         ++(*this);
Chris@16:         return tmp;
Chris@16:       }
Chris@16:       inline bool operator==(const iterator& that) const {
Chris@16:         return pLine_ == that.pLine_ && index_ == that.index_;
Chris@16:       }
Chris@16:       inline bool operator!=(const iterator& that) const {
Chris@16:         return pLine_ != that.pLine_ || index_ != that.index_;
Chris@16:       }
Chris@16:       inline Unit operator*() { return (*pLine_)[index_]; }
Chris@16:     };
Chris@16: 
Chris@16:     /*
Chris@16:      * iterator over holes contained within the figure
Chris@16:      */
Chris@16:     typedef typename std::list<ActiveTail*>::const_iterator iteratorHoles;
Chris@16: 
Chris@16:     //default constructor
Chris@16:     ActiveTail();
Chris@16: 
Chris@16:     //constructor
Chris@16:     ActiveTail(orientation_2d orient, Unit coord, Side solidToRight, ActiveTail* otherTailp);
Chris@16: 
Chris@16:     //constructor
Chris@16:     ActiveTail(PolyLine<Unit>* active, ActiveTail* otherTailp);
Chris@16: 
Chris@16:     //copy constructor
Chris@16:     ActiveTail(const ActiveTail& that);
Chris@16: 
Chris@16:     //destructor
Chris@16:     ~ActiveTail();
Chris@16: 
Chris@16:     //assignment operator
Chris@16:     ActiveTail& operator=(const ActiveTail& that);
Chris@16: 
Chris@16:     //equivalence operator
Chris@16:     bool operator==(const ActiveTail& b) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * comparison operators, ActiveTail objects are sortable by geometry
Chris@16:      */
Chris@16:     bool operator<(const ActiveTail& b) const;
Chris@16:     bool operator<=(const ActiveTail& b) const;
Chris@16:     bool operator>(const ActiveTail& b) const;
Chris@16:     bool operator>=(const ActiveTail& b) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the pointer to the polyline that this is an active tail of
Chris@16:      */
Chris@16:     PolyLine<Unit>* getTail() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the pointer to the polyline at the other end of the chain
Chris@16:      */
Chris@16:     PolyLine<Unit>* getOtherTail() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the pointer to the activetail at the other end of the chain
Chris@16:      */
Chris@16:     ActiveTail* getOtherActiveTail() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * test if another active tail is the other end of the chain
Chris@16:      */
Chris@16:     bool isOtherTail(const ActiveTail& b);
Chris@16: 
Chris@16:     /*
Chris@16:      * update this end of chain pointer to new polyline
Chris@16:      */
Chris@16:     ActiveTail& updateTail(PolyLine<Unit>* newTail);
Chris@16: 
Chris@16:     /*
Chris@16:      * associate a hole to this active tail by the specified policy
Chris@16:      */
Chris@16:     ActiveTail* addHole(ActiveTail* hole, bool fractureHoles);
Chris@16: 
Chris@16:     /*
Chris@16:      * get the list of holes
Chris@16:      */
Chris@16:     const std::list<ActiveTail*>& getHoles() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * copy holes from that to this
Chris@16:      */
Chris@16:     void copyHoles(ActiveTail& that);
Chris@16: 
Chris@16:     /*
Chris@16:      * find out if solid to right
Chris@16:      */
Chris@16:     bool solidToRight() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get coordinate (getCoord and getCoordinate are aliases for eachother)
Chris@16:      */
Chris@16:     Unit getCoord() const;
Chris@16:     Unit getCoordinate() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * get the tail orientation
Chris@16:      */
Chris@16:     orientation_2d getOrient() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * add a coordinate to the polygon at this active tail end, properly handle degenerate edges by removing redundant coordinate
Chris@16:      */
Chris@16:     void pushCoordinate(Unit coord);
Chris@16: 
Chris@16:     /*
Chris@16:      * write the figure that this active tail points to out to the temp buffer
Chris@16:      */
Chris@16:     void writeOutFigure(std::vector<Unit>& outVec, bool isHole = false) const;
Chris@16: 
Chris@16:     /*
Chris@16:      * write the figure that this active tail points to out through iterators
Chris@16:      */
Chris@16:     void writeOutFigureItrs(iterator& beginOut, iterator& endOut, bool isHole = false, orientation_2d orient = VERTICAL) const;
Chris@16:     iterator begin(bool isHole, orientation_2d orient) const;
Chris@16:     iterator end() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * write the holes that this active tail points to out through iterators
Chris@16:      */
Chris@16:     void writeOutFigureHoleItrs(iteratorHoles& beginOut, iteratorHoles& endOut) const;
Chris@16:     iteratorHoles beginHoles() const;
Chris@16:     iteratorHoles endHoles() const;
Chris@16: 
Chris@16:     /*
Chris@16:      * joins the two chains that the two active tail tails are ends of
Chris@16:      * checks for closure of figure and writes out polygons appropriately
Chris@16:      * returns a handle to a hole if one is closed
Chris@16:      */
Chris@16:     static ActiveTail* joinChains(ActiveTail* at1, ActiveTail* at2, bool solid, std::vector<Unit>& outBufferTmp);
Chris@16:     template <typename PolygonT>
Chris@16:     static ActiveTail* joinChains(ActiveTail* at1, ActiveTail* at2, bool solid, typename std::vector<PolygonT>& outBufferTmp);
Chris@16: 
Chris@16:     /*
Chris@16:      * deallocate temp buffer
Chris@16:      */
Chris@16:     static void destroyOutBuffer();
Chris@16: 
Chris@16:     /*
Chris@16:      * deallocate all polygon data this active tail points to (deep delete, call only from one of a pair of active tails)
Chris@16:      */
Chris@16:     void destroyContents();
Chris@16:   };
Chris@16: 
Chris@16:   /* allocate a polyline object */
Chris@16:   template <typename Unit>
Chris@16:   PolyLine<Unit>* createPolyLine(orientation_2d orient, Unit coord, Side side);
Chris@16: 
Chris@16:   /* deallocate a polyline object */
Chris@16:   template <typename Unit>
Chris@16:   void destroyPolyLine(PolyLine<Unit>* pLine);
Chris@16: 
Chris@16:   /* allocate an activetail object */
Chris@16:   template <typename Unit>
Chris@16:   ActiveTail<Unit>* createActiveTail();
Chris@16: 
Chris@16:   /* deallocate an activetail object */
Chris@16:   template <typename Unit>
Chris@16:   void destroyActiveTail(ActiveTail<Unit>* aTail);
Chris@16:      
Chris@16:   template<bool orientT, typename Unit>
Chris@16:   class PolyLineHoleData {
Chris@16:   private:
Chris@16:     ActiveTail<Unit>* p_;
Chris@16:   public:
Chris@16:     typedef Unit coordinate_type;
Chris@16:     typedef typename ActiveTail<Unit>::iterator compact_iterator_type;
Chris@16:     typedef iterator_compact_to_points<compact_iterator_type, point_data<coordinate_type> > iterator_type;
Chris@16:     inline PolyLineHoleData() : p_(0) {}
Chris@16:     inline PolyLineHoleData(ActiveTail<Unit>* p) : p_(p) {}
Chris@16:     //use default copy and assign
Chris@16:     inline compact_iterator_type begin_compact() const { return p_->begin(true, (orientT ? VERTICAL : HORIZONTAL)); }
Chris@16:     inline compact_iterator_type end_compact() const { return p_->end(); }
Chris@16:     inline iterator_type begin() const { return iterator_type(begin_compact(), end_compact()); }
Chris@16:     inline iterator_type end() const { return iterator_type(end_compact(), end_compact()); }
Chris@16:     inline std::size_t size() const { 
Chris@16:        return p_->getPolyLineSize();
Chris@16:     }
Chris@16:     inline ActiveTail<Unit>* yield() { return p_; }
Chris@16:     template<class iT>
Chris@16:     inline PolyLineHoleData& set(iT inputBegin, iT inputEnd) {
Chris@16:       return *this;
Chris@16:     }
Chris@16:     template<class iT>
Chris@16:     inline PolyLineHoleData& set_compact(iT inputBegin, iT inputEnd) {
Chris@16:       return *this;
Chris@16:     }
Chris@16:    
Chris@16:   };
Chris@16: 
Chris@16:   template<bool orientT, typename Unit>
Chris@16:   class PolyLinePolygonWithHolesData {
Chris@16:   private:
Chris@16:     ActiveTail<Unit>* p_;
Chris@16:   public:
Chris@16:     typedef Unit coordinate_type;
Chris@16:     typedef typename ActiveTail<Unit>::iterator compact_iterator_type;
Chris@16:     typedef iterator_compact_to_points<compact_iterator_type, point_data<coordinate_type> > iterator_type;
Chris@16:     typedef PolyLineHoleData<orientT, Unit> hole_type;
Chris@16:     typedef typename coordinate_traits<Unit>::area_type area_type;
Chris@16:     class iteratorHoles {
Chris@16:     private:
Chris@16:       typename ActiveTail<Unit>::iteratorHoles itr_;
Chris@16:     public:
Chris@16:       inline iteratorHoles() : itr_() {}
Chris@16:       inline iteratorHoles(typename ActiveTail<Unit>::iteratorHoles itr) : itr_(itr) {}
Chris@16:       //use bitwise copy and assign provided by the compiler
Chris@16:       inline iteratorHoles& operator++() {
Chris@16:         ++itr_;
Chris@16:         return *this;
Chris@16:       }
Chris@16:       inline const iteratorHoles operator++(int) {
Chris@16:         iteratorHoles tmp(*this);
Chris@16:         ++(*this);
Chris@16:         return tmp;
Chris@16:       }
Chris@16:       inline bool operator==(const iteratorHoles& that) const {
Chris@16:         return itr_ == that.itr_;
Chris@16:       }
Chris@16:       inline bool operator!=(const iteratorHoles& that) const {
Chris@16:         return itr_ != that.itr_;
Chris@16:       }
Chris@16:       inline PolyLineHoleData<orientT, Unit> operator*() { return PolyLineHoleData<orientT, Unit>(*itr_);}
Chris@16:     };
Chris@16:     typedef iteratorHoles iterator_holes_type;
Chris@16: 
Chris@16:     inline PolyLinePolygonWithHolesData() : p_(0) {}
Chris@16:     inline PolyLinePolygonWithHolesData(ActiveTail<Unit>* p) : p_(p) {}
Chris@16:     //use default copy and assign
Chris@16:     inline compact_iterator_type begin_compact() const { return p_->begin(false, (orientT ? VERTICAL : HORIZONTAL)); }
Chris@16:     inline compact_iterator_type end_compact() const { return p_->end(); }
Chris@16:     inline iterator_type begin() const { return iterator_type(begin_compact(), end_compact()); }
Chris@16:     inline iterator_type end() const { return iterator_type(end_compact(), end_compact()); }
Chris@16:     inline iteratorHoles begin_holes() const { return iteratorHoles(p_->beginHoles()); }
Chris@16:     inline iteratorHoles end_holes() const { return iteratorHoles(p_->endHoles()); }
Chris@16:     inline ActiveTail<Unit>* yield() { return p_; }
Chris@16:     //stub out these four required functions that will not be used but are needed for the interface
Chris@16:     inline std::size_t size_holes() const { return 0; }
Chris@16:     inline std::size_t size() const { return 0; }
Chris@16:     template<class iT>
Chris@16:     inline PolyLinePolygonWithHolesData& set(iT inputBegin, iT inputEnd) {
Chris@16:       return *this;
Chris@16:     }
Chris@16:     template<class iT>
Chris@16:     inline PolyLinePolygonWithHolesData& set_compact(iT inputBegin, iT inputEnd) {
Chris@16:       return *this;
Chris@16:     }
Chris@16:    
Chris@16:     // initialize a polygon from x,y values, it is assumed that the first is an x
Chris@16:     // and that the input is a well behaved polygon
Chris@16:     template<class iT>
Chris@16:     inline PolyLinePolygonWithHolesData& set_holes(iT inputBegin, iT inputEnd) {
Chris@16:       return *this;
Chris@16:     }
Chris@16:   };
Chris@16: 
Chris@16: 
Chris@16:   template <bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   struct PolyLineType { };
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct PolyLineType<orientT, Unit, polygon_90_with_holes_concept> { typedef PolyLinePolygonWithHolesData<orientT, Unit> type; };
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct PolyLineType<orientT, Unit, polygon_45_with_holes_concept> { typedef PolyLinePolygonWithHolesData<orientT, Unit> type; };
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct PolyLineType<orientT, Unit, polygon_with_holes_concept> { typedef PolyLinePolygonWithHolesData<orientT, Unit> type; };
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct PolyLineType<orientT, Unit, polygon_90_concept> { typedef PolyLineHoleData<orientT, Unit> type; };
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct PolyLineType<orientT, Unit, polygon_45_concept> { typedef PolyLineHoleData<orientT, Unit> type; };
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct PolyLineType<orientT, Unit, polygon_concept> { typedef PolyLineHoleData<orientT, Unit> type; };
Chris@16: 
Chris@16:   template <bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   class ScanLineToPolygonItrs {
Chris@16:   private:
Chris@16:     std::map<Unit, ActiveTail<Unit>*> tailMap_;
Chris@16:     typedef typename PolyLineType<orientT, Unit, polygon_concept_type>::type PolyLinePolygonData;
Chris@16:     std::vector<PolyLinePolygonData> outputPolygons_;
Chris@16:     bool fractureHoles_;
Chris@16:   public:
Chris@16:     typedef typename std::vector<PolyLinePolygonData>::iterator iterator; 
Chris@16:     inline ScanLineToPolygonItrs() : tailMap_(), outputPolygons_(), fractureHoles_(false)  {}
Chris@16:     /* construct a scanline with the proper offsets, protocol and options */
Chris@16:     inline ScanLineToPolygonItrs(bool fractureHoles) : tailMap_(), outputPolygons_(), fractureHoles_(fractureHoles) {}
Chris@16:    
Chris@16:     ~ScanLineToPolygonItrs() { clearOutput_(); }
Chris@16:    
Chris@16:     /* process all vertical edges, left and right, at a unique x coordinate, edges must be sorted low to high */
Chris@16:     void processEdges(iterator& beginOutput, iterator& endOutput, 
Chris@16:                       Unit currentX, std::vector<interval_data<Unit> >& leftEdges, 
Chris@16:                       std::vector<interval_data<Unit> >& rightEdges,
Chris@16:                       size_t vertexThreshold=(std::numeric_limits<size_t>::max)() );
Chris@16:     
Chris@16:    /**********************************************************************
Chris@16:     *methods implementing new polygon formation code                                                                    
Chris@16:     *
Chris@16:     **********************************************************************/
Chris@16:     void updatePartialSimplePolygonsWithRightEdges(Unit currentX, 
Chris@16:          const std::vector<interval_data<Unit> >& leftEdges, size_t threshold);
Chris@16: 
Chris@16:     void updatePartialSimplePolygonsWithLeftEdges(Unit currentX, 
Chris@16:          const std::vector<interval_data<Unit> >& leftEdges, size_t threshold);
Chris@16: 
Chris@16:     void closePartialSimplePolygon(Unit, ActiveTail<Unit>*, ActiveTail<Unit>*);
Chris@16: 
Chris@16:     void maintainPartialSimplePolygonInvariant(iterator& ,iterator& ,Unit,
Chris@16:          const std::vector<interval_data<Unit> >&, 
Chris@16:          const std::vector<interval_data<Unit> >&, 
Chris@16:          size_t vertexThreshold=(std::numeric_limits<size_t>::max)());
Chris@16: 
Chris@16:     void insertNewLeftEdgeIntoTailMap(Unit, Unit, Unit,
Chris@16:       typename std::map<Unit, ActiveTail<Unit>*>::iterator &);
Chris@16:     /**********************************************************************/
Chris@16: 
Chris@16:     inline size_t getTailMapSize(){
Chris@16:        typename std::map<Unit, ActiveTail<Unit>* >::const_iterator itr;
Chris@16:        size_t tsize = 0;
Chris@16:        for(itr=tailMap_.begin(); itr!=tailMap_.end(); ++itr){
Chris@16:           tsize +=  (itr->second)->getPolyLineSize();
Chris@16:        }
Chris@16:        return tsize;
Chris@16:     }
Chris@16:    /*print the active tails in this map:*/
Chris@16:    inline void print(){
Chris@16:       typename std::map<Unit, ActiveTail<Unit>* >::const_iterator itr;
Chris@16:       printf("=========TailMap[%lu]=========\n", tailMap_.size());
Chris@16:       for(itr=tailMap_.begin(); itr!=tailMap_.end(); ++itr){
Chris@16:          std::cout<< "[" << itr->first << "] : " << std::endl;
Chris@16:          //print active tail//
Chris@16:          ActiveTail<Unit> const *t = (itr->second);
Chris@16:          PolyLine<Unit> const *pBegin = t->getTail();
Chris@16:          PolyLine<Unit> const *pEnd = t->getOtherActiveTail()->getTail();
Chris@16:          std::string sorient = pBegin->solidToRight() ? "RIGHT" : "LEFT"; 
Chris@16:          std::cout<< " ActiveTail.tailp_ (solid= " << sorient ;
Chris@16:          End dir = TAIL;
Chris@16:          while(pBegin!=pEnd){
Chris@16:             std::cout << pBegin  << "={ ";
Chris@16:             for(size_t i=0; i<pBegin->numSegments(); i++){
Chris@16:                point_data<Unit> u = pBegin->getPoint(i);
Chris@16:                std::cout << "(" << u.x() << "," << u.y() << ") ";
Chris@16:             }
Chris@16:             std::cout << "}  ";
Chris@16:             pBegin = pBegin->next(dir == HEAD ? TAIL : HEAD);
Chris@16:             dir = pBegin->endConnectivity(dir == HEAD ? TAIL : HEAD);
Chris@16:          }
Chris@16:          if(pEnd){
Chris@16:             std::cout << pEnd << "={ ";
Chris@16:             for(size_t i=0; i<pEnd->numSegments(); i++){
Chris@16:                point_data<Unit> u = pEnd->getPoint(i);
Chris@16:                std::cout << "(" << u.x() << "," << u.y() << ") ";
Chris@16:             }
Chris@16:             std::cout << "}  ";
Chris@16:          }
Chris@16:          std::cout << " end= " << pEnd << std::endl;
Chris@16:       }
Chris@16:    }
Chris@16:    
Chris@16:   private:
Chris@16:     void clearOutput_();
Chris@16:   };
Chris@16: 
Chris@16:   /*
Chris@16:    * ScanLine does all the work of stitching together polygons from incoming vertical edges
Chris@16:    */
Chris@16: //   template <typename Unit, typename polygon_concept_type>
Chris@16: //   class ScanLineToPolygons {
Chris@16: //   private:
Chris@16: //     ScanLineToPolygonItrs<true, Unit> scanline_;
Chris@16: //   public:
Chris@16: //     inline ScanLineToPolygons() : scanline_() {}
Chris@16: //     /* construct a scanline with the proper offsets, protocol and options */
Chris@16: //     inline ScanLineToPolygons(bool fractureHoles) : scanline_(fractureHoles) {}
Chris@16:    
Chris@16: //     /* process all vertical edges, left and right, at a unique x coordinate, edges must be sorted low to high */
Chris@16: //     inline void processEdges(std::vector<Unit>& outBufferTmp, Unit currentX, std::vector<interval_data<Unit> >& leftEdges, 
Chris@16: //                              std::vector<interval_data<Unit> >& rightEdges) {
Chris@16: //       typename ScanLineToPolygonItrs<true, Unit>::iterator itr, endItr;
Chris@16: //       scanline_.processEdges(itr, endItr, currentX, leftEdges, rightEdges);
Chris@16: //       //copy data into outBufferTmp
Chris@16: //       while(itr != endItr) {
Chris@16: //         typename PolyLinePolygonData<true, Unit>::iterator pditr;
Chris@16: //         outBufferTmp.push_back(0);
Chris@16: //         unsigned int sizeIndex = outBufferTmp.size() - 1;
Chris@16: //         int count = 0;
Chris@16: //         for(pditr = (*itr).begin(); pditr != (*itr).end(); ++pditr) {
Chris@16: //           outBufferTmp.push_back(*pditr);
Chris@16: //           ++count;
Chris@16: //         }
Chris@16: //         outBufferTmp[sizeIndex] = count;
Chris@16: //         typename PolyLinePolygonData<true, Unit>::iteratorHoles pdHoleItr;
Chris@16: //         for(pdHoleItr = (*itr).beginHoles(); pdHoleItr != (*itr).endHoles(); ++pdHoleItr) {
Chris@16: //           outBufferTmp.push_back(0);
Chris@16: //           unsigned int sizeIndex2 = outBufferTmp.size() - 1;
Chris@16: //           int count2 = 0;
Chris@16: //           for(pditr = (*pdHoleItr).begin(); pditr != (*pdHoleItr).end(); ++pditr) {
Chris@16: //             outBufferTmp.push_back(*pditr);
Chris@16: //             ++count2;
Chris@16: //           }
Chris@16: //           outBufferTmp[sizeIndex2] = -count;
Chris@16: //         }
Chris@16: //         ++itr;
Chris@16: //       }
Chris@16: //     }
Chris@16: //   };
Chris@16: 
Chris@16:   const int VERTICAL_HEAD = 1, HEAD_TO_TAIL = 2, TAIL_TO_TAIL = 4, SOLID_TO_RIGHT = 8;
Chris@16: 
Chris@16:   //EVERY FUNCTION in this DEF file should be explicitly defined as inline
Chris@16: 
Chris@16:   //microsoft compiler improperly warns whenever you cast an integer to bool
Chris@16:   //call this function on an integer to convert it to bool without a warning
Chris@16:   template <class T>
Chris@16:   inline bool to_bool(const T& val) { return val != 0; }
Chris@16: 
Chris@16:   //default constructor (for preallocation)
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>::PolyLine() : ptdata_() ,headp_(0), tailp_(0), state_(-1) {}
Chris@16: 
Chris@16:   //constructor
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>::PolyLine(orientation_2d orient, Unit coord, Side side) : 
Chris@16:     ptdata_(1, coord),
Chris@16:     headp_(0),
Chris@16:     tailp_(0),
Chris@16:     state_(orient.to_int() +
Chris@16:            (side << 3)){}
Chris@16: 
Chris@16:   //copy constructor
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>::PolyLine(const PolyLine<Unit>& pline) : ptdata_(pline.ptdata_),
Chris@16:                                                      headp_(pline.headp_),
Chris@16:                                                      tailp_(pline.tailp_),
Chris@16:                                                      state_(pline.state_) {}
Chris@16: 
Chris@16:   //destructor
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>::~PolyLine() {
Chris@16:     //clear out data just in case it is read later
Chris@16:     headp_ = tailp_ = 0;
Chris@16:     state_ = 0;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::operator=(const PolyLine<Unit>& that) {
Chris@16:     if(!(this == &that)) {
Chris@16:       headp_ = that.headp_;
Chris@16:       tailp_ = that.tailp_;
Chris@16:       ptdata_ = that.ptdata_;
Chris@16:       state_ = that.state_;
Chris@16:     }
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::operator==(const PolyLine<Unit>& b) const {
Chris@16:     return this == &b || (state_ == b.state_ &&
Chris@16:                           headp_ == b.headp_ &&
Chris@16:                           tailp_ == b.tailp_);
Chris@16:   }
Chris@16: 
Chris@16:   //valid PolyLine
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::isValid() const { 
Chris@16:     return state_ > -1; }
Chris@16: 
Chris@16:   //first coordinate is an X value
Chris@16:   //first segment is vertical
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::verticalHead() const {
Chris@16:     return state_ & VERTICAL_HEAD;
Chris@16:   }
Chris@16: 
Chris@16:   //retrun true is PolyLine has odd number of coordiantes
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::oddLength() const {
Chris@16:     return to_bool((ptdata_.size()-1) % 2);
Chris@16:   }
Chris@16: 
Chris@16:   //last coordiante is an X value
Chris@16:   //last segment is vertical
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::verticalTail() const {
Chris@16:     return to_bool(verticalHead() ^ oddLength());
Chris@16:   }
Chris@16:      
Chris@16:   template <typename Unit>
Chris@16:   inline orientation_2d PolyLine<Unit>::tailOrient() const {
Chris@16:     return (verticalTail() ? VERTICAL : HORIZONTAL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline orientation_2d PolyLine<Unit>::headOrient() const {
Chris@16:     return (verticalHead() ? VERTICAL : HORIZONTAL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline End PolyLine<Unit>::endConnectivity(End end) const {
Chris@16:     //Tail should be defined as true
Chris@16:     if(end) { return tailToTail(); }
Chris@16:     return headToTail();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::headToTail() const {
Chris@16:     return to_bool(state_ & HEAD_TO_TAIL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::headToHead() const {
Chris@16:     return to_bool(!headToTail());
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::tailToHead() const {
Chris@16:     return to_bool(!tailToTail());
Chris@16:   }
Chris@16:      
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::tailToTail() const {
Chris@16:     return to_bool(state_ & TAIL_TO_TAIL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline Side PolyLine<Unit>::solidSide() const { 
Chris@16:     return solidToRight(); }
Chris@16:       
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::solidToRight() const {
Chris@16:     return to_bool(state_ & SOLID_TO_RIGHT) != 0;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool PolyLine<Unit>::active() const {
Chris@16:     return !to_bool(tailp_);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::pushCoordinate(Unit coord) {
Chris@16:     ptdata_.push_back(coord);
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::popCoordinate() {
Chris@16:     ptdata_.pop_back();
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::pushPoint(const point_data<Unit>& point) {
Chris@16:      if(numSegments()){
Chris@16:        point_data<Unit> endPt = getEndPoint();
Chris@16:        //vertical is true, horizontal is false
Chris@16:        if((tailOrient().to_int() ? point.get(VERTICAL) == endPt.get(VERTICAL) : point.get(HORIZONTAL) == endPt.get(HORIZONTAL))) {
Chris@16:          //we were pushing a colinear segment
Chris@16:          return popCoordinate();
Chris@16:        }
Chris@16:      }
Chris@16:     return pushCoordinate(tailOrient().to_int() ? point.get(VERTICAL) : point.get(HORIZONTAL));
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::extendTail(Unit delta) {
Chris@16:     ptdata_.back() += delta;
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   //private member function that creates a link from this PolyLine to that
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinTo_(End thisEnd, PolyLine<Unit>& that, End end) {
Chris@16:     if(thisEnd){
Chris@16:       tailp_ = &that;
Chris@16:       state_ &= ~TAIL_TO_TAIL; //clear any previous state_ of bit (for safety)
Chris@16:       state_ |= (end << 2); //place bit into mask
Chris@16:     } else {
Chris@16:       headp_ = &that;
Chris@16:       state_ &= ~HEAD_TO_TAIL; //clear any previous state_ of bit (for safety)
Chris@16:       state_ |= (end << 1); //place bit into mask
Chris@16:     }
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   //join two PolyLines (both ways of the association)
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinTo(End thisEnd, PolyLine<Unit>& that, End end) {
Chris@16:     joinTo_(thisEnd, that, end);
Chris@16:     that.joinTo_(end, *this, thisEnd);
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   //convenience functions for joining PolyLines
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinToTail(PolyLine<Unit>& that, End end) {
Chris@16:     return joinTo(TAIL, that, end);
Chris@16:   }
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinToHead(PolyLine<Unit>& that, End end) {
Chris@16:     return joinTo(HEAD, that, end);
Chris@16:   }
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinHeadToHead(PolyLine<Unit>& that) {
Chris@16:     return joinToHead(that, HEAD);
Chris@16:   }
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinHeadToTail(PolyLine<Unit>& that) {
Chris@16:     return joinToHead(that, TAIL);
Chris@16:   }
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinTailToHead(PolyLine<Unit>& that) {
Chris@16:     return joinToTail(that, HEAD);
Chris@16:   }
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::joinTailToTail(PolyLine<Unit>& that) {
Chris@16:     return joinToTail(that, TAIL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>& PolyLine<Unit>::disconnectTails() {
Chris@16:     next(TAIL)->state_ &= !TAIL_TO_TAIL;
Chris@16:     next(TAIL)->tailp_ = 0;
Chris@16:     state_ &= !TAIL_TO_TAIL;
Chris@16:     tailp_ = 0;
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline Unit PolyLine<Unit>::getEndCoord(End end) const {
Chris@16:     if(end)
Chris@16:       return ptdata_.back();
Chris@16:     return ptdata_.front();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline orientation_2d PolyLine<Unit>::segmentOrient(unsigned int index) const {
Chris@16:     return (to_bool((unsigned int)verticalHead() ^ (index % 2)) ? VERTICAL : HORIZONTAL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline point_data<Unit> PolyLine<Unit>::getPoint(unsigned int index) const {
Chris@16:     //assert(isValid() && headp_->isValid()) ("PolyLine: headp_ must be valid");
Chris@16:     point_data<Unit> pt;
Chris@16:     pt.set(HORIZONTAL, ptdata_[index]);
Chris@16:     pt.set(VERTICAL, ptdata_[index]);
Chris@16:     Unit prevCoord;
Chris@16:     if(index == 0) {
Chris@16:       prevCoord = headp_->getEndCoord(headToTail());
Chris@16:     } else {
Chris@16:       prevCoord = ptdata_[index-1];
Chris@16:     }
Chris@16:     pt.set(segmentOrient(index), prevCoord);
Chris@16:     return pt;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline point_data<Unit> PolyLine<Unit>::getEndPoint(End end) const {
Chris@16:     return getPoint((end ? numSegments() - 1 : (unsigned int)0));
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline Unit PolyLine<Unit>::operator[] (unsigned int index) const {
Chris@16:     //assert(ptdata_.size() > index) ("PolyLine: out of bounds index");
Chris@16:     return ptdata_[index];
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline unsigned int PolyLine<Unit>::numSegments() const {
Chris@16:     return ptdata_.size();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>* PolyLine<Unit>::next(End end) const {
Chris@16:     return (end ? tailp_ : headp_);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>::ActiveTail() : tailp_(0), otherTailp_(0), holesList_(), 
Chris@16:    polyLineSize_(0) {}
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>::ActiveTail(orientation_2d orient, Unit coord, Side solidToRight, ActiveTail* otherTailp) : 
Chris@16:     tailp_(0), otherTailp_(0), holesList_(), polyLineSize_(0) {
Chris@16:     tailp_ = createPolyLine(orient, coord, solidToRight);
Chris@16:     otherTailp_ = otherTailp;
Chris@16:     polyLineSize_ = tailp_->numSegments();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>::ActiveTail(PolyLine<Unit>* active, ActiveTail<Unit>* otherTailp) : 
Chris@16:     tailp_(active), otherTailp_(otherTailp), holesList_(), 
Chris@16:       polyLineSize_(0) {}
Chris@16: 
Chris@16:   //copy constructor
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>::ActiveTail(const ActiveTail<Unit>& that) : tailp_(that.tailp_), otherTailp_(that.otherTailp_), holesList_(), polyLineSize_(that.polyLineSize_) {}
Chris@16: 
Chris@16:   //destructor
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>::~ActiveTail() { 
Chris@16:     //clear them in case the memory is read later
Chris@16:     tailp_ = 0; otherTailp_ = 0; 
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>& ActiveTail<Unit>::operator=(const ActiveTail<Unit>& that) {
Chris@16:     //self assignment is safe in this case
Chris@16:     tailp_ = that.tailp_;
Chris@16:     otherTailp_ = that.otherTailp_;
Chris@16:     polyLineSize_ = that.polyLineSize_;
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::operator==(const ActiveTail<Unit>& b) const {
Chris@16:     return tailp_ == b.tailp_ && otherTailp_ == b.otherTailp_;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::operator<(const ActiveTail<Unit>& b) const {
Chris@16:     return tailp_->getEndPoint().get(VERTICAL) < b.tailp_->getEndPoint().get(VERTICAL);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::operator<=(const ActiveTail<Unit>& b) const { 
Chris@16:     return !(*this > b); }
Chris@16:    
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::operator>(const ActiveTail<Unit>& b) const { 
Chris@16:     return b < (*this); }
Chris@16:    
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::operator>=(const ActiveTail<Unit>& b) const { 
Chris@16:     return !(*this < b); }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>* ActiveTail<Unit>::getTail() const { 
Chris@16:     return tailp_; }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>* ActiveTail<Unit>::getOtherTail() const { 
Chris@16:     return otherTailp_->tailp_; }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>* ActiveTail<Unit>::getOtherActiveTail() const { 
Chris@16:     return otherTailp_; }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::isOtherTail(const ActiveTail<Unit>& b) {
Chris@16:     //       assert( (tailp_ == b.getOtherTail() && getOtherTail() == b.tailp_) ||
Chris@16:     //                     (tailp_ != b.getOtherTail() && getOtherTail() != b.tailp_)) 
Chris@16:     //         ("ActiveTail: Active tails out of sync");
Chris@16:     return otherTailp_ == &b;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>& ActiveTail<Unit>::updateTail(PolyLine<Unit>* newTail) {
Chris@16:     //subtract the old size and add new size//
Chris@16:     int delta = newTail->numSegments() - tailp_->numSegments();
Chris@16:     addPolyLineSize(delta);
Chris@16:     otherTailp_->addPolyLineSize(delta);
Chris@16:     tailp_ = newTail;
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>* ActiveTail<Unit>::addHole(ActiveTail<Unit>* hole, bool fractureHoles) {
Chris@16: 
Chris@16:     if(!fractureHoles){
Chris@16:       holesList_.push_back(hole);
Chris@16:       copyHoles(*hole);
Chris@16:       copyHoles(*(hole->getOtherActiveTail()));
Chris@16:       return this;
Chris@16:     }
Chris@16:     ActiveTail<Unit>* h, *v;
Chris@16:     ActiveTail<Unit>* other = hole->getOtherActiveTail();
Chris@16:     if(other->getOrient() == VERTICAL) {
Chris@16:       //assert that hole.getOrient() == HORIZONTAL
Chris@16:       //this case should never happen
Chris@16:       h = hole;  
Chris@16:       v = other;
Chris@16:     } else {
Chris@16:       //assert that hole.getOrient() == VERTICAL
Chris@16:       h = other;
Chris@16:       v = hole;
Chris@16:     }
Chris@16:     h->pushCoordinate(v->getCoordinate());
Chris@16:     //assert that h->getOrient() == VERTICAL
Chris@16:     //v->pushCoordinate(getCoordinate());
Chris@16:     //assert that v->getOrient() == VERTICAL
Chris@16:     //I can't close a figure by adding a hole, so pass zero for xMin and yMin
Chris@16:     std::vector<Unit> tmpVec;
Chris@16:     ActiveTail<Unit>::joinChains(this, h, false, tmpVec);
Chris@16:     return v;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline const std::list<ActiveTail<Unit>*>& ActiveTail<Unit>::getHoles() const {
Chris@16:     return holesList_;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void ActiveTail<Unit>::copyHoles(ActiveTail<Unit>& that) {
Chris@16:     holesList_.splice(holesList_.end(), that.holesList_); //splice the two lists together
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline bool ActiveTail<Unit>::solidToRight() const { 
Chris@16:     return getTail()->solidToRight(); }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline Unit ActiveTail<Unit>::getCoord() const { 
Chris@16:     return getTail()->getEndCoord(); }
Chris@16:  
Chris@16:   template <typename Unit>
Chris@16:   inline Unit ActiveTail<Unit>::getCoordinate() const { 
Chris@16:     return getCoord(); } 
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline orientation_2d ActiveTail<Unit>::getOrient() const { 
Chris@16:     return getTail()->tailOrient(); }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void ActiveTail<Unit>::pushCoordinate(Unit coord) { 
Chris@16:     //appropriately handle any co-linear polyline segments by calling push point internally
Chris@16:     point_data<Unit> p;
Chris@16:     p.set(HORIZONTAL, coord);
Chris@16:     p.set(VERTICAL, coord);
Chris@16:     //if we are vertical assign the last coordinate (an X) to p.x, else to p.y
Chris@16:     p.set(getOrient().get_perpendicular(), getCoordinate());
Chris@16:     int oldSegments = tailp_->numSegments();
Chris@16:     tailp_->pushPoint(p);
Chris@16:     int delta = tailp_->numSegments() - oldSegments;
Chris@16:     addPolyLineSize(delta);
Chris@16:     otherTailp_->addPolyLineSize(delta);
Chris@16:   }
Chris@16: 
Chris@16: 
Chris@16:   //global utility functions
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>* createPolyLine(orientation_2d orient, Unit coord, Side side) {
Chris@16:     return new PolyLine<Unit>(orient, coord, side);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void destroyPolyLine(PolyLine<Unit>* pLine) {
Chris@16:     delete pLine;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>* createActiveTail() {
Chris@16:     //consider replacing system allocator with ActiveTail memory pool
Chris@16:     return new ActiveTail<Unit>();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void destroyActiveTail(ActiveTail<Unit>* aTail) {
Chris@16:     delete aTail;
Chris@16:   }
Chris@16: 
Chris@16: 
Chris@16:   //no recursion, to prevent max recursion depth errors
Chris@16:   template <typename Unit>
Chris@16:   inline void ActiveTail<Unit>::destroyContents() {
Chris@16:     tailp_->disconnectTails();
Chris@16:     PolyLine<Unit>* nextPolyLinep = tailp_->next(HEAD);
Chris@16:     End end = tailp_->endConnectivity(HEAD);
Chris@16:     destroyPolyLine(tailp_);
Chris@16:     while(nextPolyLinep) {
Chris@16:       End nextEnd = nextPolyLinep->endConnectivity(!end); //get the direction of next polyLine
Chris@16:       PolyLine<Unit>* nextNextPolyLinep = nextPolyLinep->next(!end); //get the next polyline
Chris@16:       destroyPolyLine(nextPolyLinep); //destroy the current polyline
Chris@16:       end = nextEnd;
Chris@16:       nextPolyLinep = nextNextPolyLinep;
Chris@16:     }
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline typename ActiveTail<Unit>::iterator ActiveTail<Unit>::begin(bool isHole, orientation_2d orient) const {
Chris@16:     return iterator(this, isHole, orient);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline typename ActiveTail<Unit>::iterator ActiveTail<Unit>::end() const {
Chris@16:     return iterator();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline typename ActiveTail<Unit>::iteratorHoles ActiveTail<Unit>::beginHoles() const {
Chris@16:     return holesList_.begin();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline typename ActiveTail<Unit>::iteratorHoles ActiveTail<Unit>::endHoles() const {
Chris@16:     return holesList_.end();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void ActiveTail<Unit>::writeOutFigureItrs(iterator& beginOut, iterator& endOut, bool isHole, orientation_2d orient) const {
Chris@16:     beginOut = begin(isHole, orient);
Chris@16:     endOut = end();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void ActiveTail<Unit>::writeOutFigureHoleItrs(iteratorHoles& beginOut, iteratorHoles& endOut) const {
Chris@16:     beginOut = beginHoles();
Chris@16:     endOut = endHoles();
Chris@16:   }
Chris@16: 
Chris@16:   template <typename Unit>
Chris@16:   inline void ActiveTail<Unit>::writeOutFigure(std::vector<Unit>& outVec, bool isHole) const {
Chris@16:     //we start writing out the polyLine that this active tail points to at its tail
Chris@16:     std::size_t size = outVec.size();
Chris@16:     outVec.push_back(0); //place holder for size
Chris@16:     PolyLine<Unit>* nextPolyLinep = 0;
Chris@16:     if(!isHole){
Chris@16:       nextPolyLinep = otherTailp_->tailp_->writeOut(outVec);
Chris@16:     } else {
Chris@16:       nextPolyLinep = tailp_->writeOut(outVec);
Chris@16:     }
Chris@16:     Unit firsty = outVec[size + 1];
Chris@16:     if((getOrient() == HORIZONTAL) ^ !isHole) {
Chris@16:       //our first coordinate is a y value, so we need to rotate it to the end
Chris@16:       typename std::vector<Unit>::iterator tmpItr = outVec.begin();
Chris@16:       tmpItr += size; 
Chris@16:       outVec.erase(++tmpItr); //erase the 2nd element
Chris@16:     }
Chris@16:     End startEnd = tailp_->endConnectivity(HEAD);
Chris@16:     if(isHole) startEnd = otherTailp_->tailp_->endConnectivity(HEAD);
Chris@16:     while(nextPolyLinep) {
Chris@16:       bool nextStartEnd = nextPolyLinep->endConnectivity(!startEnd);
Chris@16:       nextPolyLinep = nextPolyLinep->writeOut(outVec, startEnd); 
Chris@16:       startEnd = nextStartEnd;
Chris@16:     }      
Chris@16:     if((getOrient() == HORIZONTAL) ^ !isHole) {
Chris@16:       //we want to push the y value onto the end since we ought to have ended with an x
Chris@16:       outVec.push_back(firsty); //should never be executed because we want first value to be an x
Chris@16:     }
Chris@16:     //the vector contains the coordinates of the linked list of PolyLines in the correct order
Chris@16:     //first element is supposed to be the size
Chris@16:     outVec[size] = outVec.size() - 1 - size;  //number of coordinates in vector
Chris@16:     //assert outVec[size] % 2 == 0 //it should be even
Chris@16:     //make the size negative for holes
Chris@16:     outVec[size] *= (isHole ? -1 : 1);
Chris@16:   }
Chris@16: 
Chris@16:   //no recursion to prevent max recursion depth errors
Chris@16:   template <typename Unit>
Chris@16:   inline PolyLine<Unit>* PolyLine<Unit>::writeOut(std::vector<Unit>& outVec, End startEnd) const {
Chris@16:     if(startEnd == HEAD){
Chris@16:       //forward order
Chris@16:       outVec.insert(outVec.end(), ptdata_.begin(), ptdata_.end());
Chris@16:       return tailp_;
Chris@16:     }else{
Chris@16:       //reverse order
Chris@16:       //do not reserve because we expect outVec to be large enough already
Chris@16:       for(int i = ptdata_.size() - 1; i >= 0; --i){
Chris@16:         outVec.push_back(ptdata_[i]);
Chris@16:       }
Chris@16:       //NT didn't know about this version of the API....
Chris@16:       //outVec.insert(outVec.end(), ptdata_.rbegin(), ptdata_.rend());
Chris@16:       return headp_;
Chris@16:     }
Chris@16:   }
Chris@16: 
Chris@16:   //solid indicates if it was joined by a solit or a space
Chris@16:   template <typename Unit>
Chris@16:   inline ActiveTail<Unit>* ActiveTail<Unit>::joinChains(ActiveTail<Unit>* at1, ActiveTail<Unit>* at2, bool solid, std::vector<Unit>& outBufferTmp) 
Chris@16:   {
Chris@16:     //checks to see if we closed a figure
Chris@16:     if(at1->isOtherTail(*at2)){
Chris@16:       //value of solid tells us if we closed solid or hole
Chris@16:       //and output the solid or handle the hole appropriately
Chris@16:       //if the hole needs to fracture across horizontal partition boundary we need to notify
Chris@16:       //the calling context to do so
Chris@16:       if(solid) {
Chris@16:         //the chains are being joined because there is solid to the right
Chris@16:         //this means that if the figure is closed at this point it must be a hole
Chris@16:         //because otherwise it would have to have another vertex to the right of this one
Chris@16:         //and would not be closed at this point
Chris@16:         return at1;
Chris@16:       } else {
Chris@16:         //assert pG != 0
Chris@16:         //the figure that was closed is a shell
Chris@16:         at1->writeOutFigure(outBufferTmp);
Chris@16:         //process holes of the polygon
Chris@16:         at1->copyHoles(*at2); //there should not be holes on at2, but if there are, copy them over
Chris@16:         const std::list<ActiveTail<Unit>*>& holes = at1->getHoles();
Chris@16:         for(typename std::list<ActiveTail<Unit>*>::const_iterator litr = holes.begin(); litr != holes.end(); ++litr) {
Chris@16:           (*litr)->writeOutFigure(outBufferTmp, true);
Chris@16:           //delete the hole
Chris@16:           (*litr)->destroyContents();
Chris@16:           destroyActiveTail((*litr)->getOtherActiveTail());
Chris@16:           destroyActiveTail((*litr));
Chris@16:         }
Chris@16:         //delete the polygon
Chris@16:         at1->destroyContents();
Chris@16:         //at2 contents are the same as at1, so it should not destroy them
Chris@16:         destroyActiveTail(at1);
Chris@16:         destroyActiveTail(at2);
Chris@16:       }
Chris@16:       return 0;
Chris@16:     }
Chris@16:     //join the two partial polygons into one large partial polygon
Chris@16:     at1->getTail()->joinTailToTail(*(at2->getTail()));
Chris@16:     *(at1->getOtherActiveTail()) = ActiveTail(at1->getOtherTail(), at2->getOtherActiveTail());
Chris@16:     *(at2->getOtherActiveTail()) = ActiveTail(at2->getOtherTail(), at1->getOtherActiveTail());
Chris@16: 
Chris@16:     int accumulate = at2->getPolyLineSize() + at1->getPolyLineSize();
Chris@16:     (at1->getOtherActiveTail())->setPolyLineSize(accumulate);
Chris@16:     (at2->getOtherActiveTail())->setPolyLineSize(accumulate);
Chris@16: 
Chris@16:     at1->getOtherActiveTail()->copyHoles(*at1);
Chris@16:     at1->getOtherActiveTail()->copyHoles(*at2);
Chris@16:     destroyActiveTail(at1);
Chris@16:     destroyActiveTail(at2);
Chris@16:     return 0;
Chris@16:   }
Chris@16: 
Chris@16:   //solid indicates if it was joined by a solit or a space
Chris@16:   template <typename Unit>
Chris@16:   template <typename PolygonT>
Chris@16:   inline ActiveTail<Unit>* ActiveTail<Unit>::joinChains(ActiveTail<Unit>* at1, ActiveTail<Unit>* at2, bool solid, 
Chris@16:                                                         std::vector<PolygonT>& outBufferTmp) {
Chris@16:     //checks to see if we closed a figure
Chris@16:     if(at1->isOtherTail(*at2)){
Chris@16:       //value of solid tells us if we closed solid or hole
Chris@16:       //and output the solid or handle the hole appropriately
Chris@16:       //if the hole needs to fracture across horizontal partition boundary we need to notify
Chris@16:       //the calling context to do so
Chris@16:       if(solid) {
Chris@16:         //the chains are being joined because there is solid to the right
Chris@16:         //this means that if the figure is closed at this point it must be a hole
Chris@16:         //because otherwise it would have to have another vertex to the right of this one
Chris@16:         //and would not be closed at this point
Chris@16:         return at1;
Chris@16:       } else {    
Chris@16:         //assert pG != 0
Chris@16:         //the figure that was closed is a shell
Chris@16:         outBufferTmp.push_back(at1);
Chris@16:         at1->copyHoles(*at2); //there should not be holes on at2, but if there are, copy them over
Chris@16:       }
Chris@16:       return 0;
Chris@16:     }
Chris@16:     //join the two partial polygons into one large partial polygon
Chris@16:     at1->getTail()->joinTailToTail(*(at2->getTail()));
Chris@16:     *(at1->getOtherActiveTail()) = ActiveTail<Unit>(at1->getOtherTail(), at2->getOtherActiveTail());
Chris@16:     *(at2->getOtherActiveTail()) = ActiveTail<Unit>(at2->getOtherTail(), at1->getOtherActiveTail());
Chris@16: 
Chris@16:     int accumulate = at2->getPolyLineSize() + at1->getPolyLineSize();
Chris@16:     (at1->getOtherActiveTail())->setPolyLineSize(accumulate);
Chris@16:     (at2->getOtherActiveTail())->setPolyLineSize(accumulate);
Chris@16: 
Chris@16:     at1->getOtherActiveTail()->copyHoles(*at1);
Chris@16:     at1->getOtherActiveTail()->copyHoles(*at2);
Chris@16:     destroyActiveTail(at1);
Chris@16:     destroyActiveTail(at2);
Chris@16:     return 0;
Chris@16:   }
Chris@16: 
Chris@16:   template <class TKey, class T> inline typename std::map<TKey, T>::iterator findAtNext(std::map<TKey, T>& theMap, 
Chris@16:                                                                                         typename std::map<TKey, T>::iterator pos, const TKey& key) 
Chris@16:   {
Chris@16:     if(pos == theMap.end()) return theMap.find(key);
Chris@16:     //if they match the mapItr is pointing to the correct position
Chris@16:     if(pos->first < key) {
Chris@16:       return theMap.find(key);
Chris@16:     }
Chris@16:     if(pos->first > key) {
Chris@16:       return theMap.end();
Chris@16:     } 
Chris@16:     //else they are equal and no need to do anything to the iterator
Chris@16:     return pos;
Chris@16:   }
Chris@16: 
Chris@16:   // createActiveTailsAsPair is called in these two end cases of geometry
Chris@16:   // 1. lower left concave corner
Chris@16:   //         ###| 
Chris@16:   //         ###|
Chris@16:   //         ###|### 
Chris@16:   //         ###|###
Chris@16:   // 2. lower left convex corner
Chris@16:   //            |###          
Chris@16:   //            |###         
Chris@16:   //            |            
Chris@16:   //            |     
Chris@16:   // In case 1 there may be a hole propigated up from the bottom.  If the fracture option is enabled
Chris@16:   // the two active tails that form the filament fracture line edges can become the new active tail pair
Chris@16:   // by pushing x and y onto them.  Otherwise the hole simply needs to be associated to one of the new active tails
Chris@16:   // with add hole
Chris@16:   template <typename Unit>
Chris@16:   inline std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> createActiveTailsAsPair(Unit x, Unit y, bool solid, ActiveTail<Unit>* phole, bool fractureHoles) {
Chris@16:     ActiveTail<Unit>* at1 = 0;
Chris@16:     ActiveTail<Unit>* at2 = 0;
Chris@16:     if(!phole || !fractureHoles){
Chris@16:       at1 = createActiveTail<Unit>();
Chris@16:       at2 = createActiveTail<Unit>();
Chris@16:       (*at1) = ActiveTail<Unit>(VERTICAL, x, solid, at2);
Chris@16:       (*at2) = ActiveTail<Unit>(HORIZONTAL, y, !solid, at1);
Chris@16:       //provide a function through activeTail class to provide this
Chris@16:       at1->getTail()->joinHeadToHead(*(at2->getTail()));
Chris@16: 
Chris@16:       at1->addPolyLineSize(1);
Chris@16:       at2->addPolyLineSize(1);
Chris@16: 
Chris@16:       if(phole) 
Chris@16:         at1->addHole(phole, fractureHoles); //assert fractureHoles == false
Chris@16:       return std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*>(at1, at2);
Chris@16:     }
Chris@16:     //assert phole is not null
Chris@16:     //assert fractureHoles is true
Chris@16:     if(phole->getOrient() == VERTICAL) {
Chris@16:       at2 = phole;
Chris@16:     } else {
Chris@16:       at2 = phole->getOtherActiveTail(); //should never be executed since orientation is expected to be vertical
Chris@16:     }
Chris@16:     //assert solid == false, we should be creating a corner with solid below and to the left if there was a hole
Chris@16:     at1 = at2->getOtherActiveTail();
Chris@16:     //assert at1 is horizontal
Chris@16:     at1->pushCoordinate(x);
Chris@16:     //assert at2 is vertical
Chris@16:     at2->pushCoordinate(y);
Chris@16: 
Chris@16:     return std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*>(at1, at2);
Chris@16:   }
Chris@16: 
Chris@16:   /* 
Chris@16:    *     |
Chris@16:    *     |
Chris@16:    *     =
Chris@16:    *     |########
Chris@16:    *     |########  (add a new ActiveTail in the tailMap_).
Chris@16:    *     |########
Chris@16:    *     |########
Chris@16:    *     |########
Chris@16:    *     =
Chris@16:    *     |
Chris@16:    *     |
Chris@16:    *
Chris@16:    * NOTE: Call this only if you are sure that the $ledege$ is not in the tailMap_
Chris@16:    */
Chris@16:   template<bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
Chris@16:   insertNewLeftEdgeIntoTailMap(Unit currentX, Unit yBegin, Unit yEnd,
Chris@16:    typename std::map<Unit, ActiveTail<Unit> *>::iterator &hint){
Chris@16:      ActiveTail<Unit> *currentTail = NULL;
Chris@16:      std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair = 
Chris@16:       createActiveTailsAsPair(currentX, yBegin, true, currentTail, 
Chris@16:          fractureHoles_);
Chris@16:      currentTail = tailPair.first; 
Chris@16:      if(!tailMap_.empty()){
Chris@16:         ++hint;
Chris@16:      }
Chris@16:      hint = tailMap_.insert(hint, std::make_pair(yBegin, tailPair.second));
Chris@16:      currentTail->pushCoordinate(yEnd); ++hint;
Chris@16:      hint = tailMap_.insert(hint, std::make_pair(yEnd, currentTail));
Chris@16:   }
Chris@16: 
Chris@16:   template<bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
Chris@16:   closePartialSimplePolygon(Unit currentX, ActiveTail<Unit>*pfig,
Chris@16:       ActiveTail<Unit>*ppfig){
Chris@16:      pfig->pushCoordinate(currentX);
Chris@16:      ActiveTail<Unit>::joinChains(pfig, ppfig, false, outputPolygons_);
Chris@16:   }
Chris@16:   /*
Chris@16:    * If the invariant is maintained correctly then left edges can do the
Chris@16:    * following.
Chris@16:    *
Chris@16:    *               =###
Chris@16:    *            #######
Chris@16:    *            #######
Chris@16:    *            #######
Chris@16:    *            #######
Chris@16:    *               =###
Chris@16:    *               |### (input left edge)
Chris@16:    *               |###
Chris@16:    *               =###
Chris@16:    *            #######
Chris@16:    *            #######
Chris@16:    *               =###
Chris@16:    */
Chris@16:   template<bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
Chris@16:   updatePartialSimplePolygonsWithLeftEdges(Unit currentX,
Chris@16:    const std::vector<interval_data<Unit> > &leftEdges, size_t vertexThreshold){
Chris@16:      typename std::map<Unit, ActiveTail<Unit>* >::iterator succ, succ1;
Chris@16:      typename std::map<Unit, ActiveTail<Unit>* >::iterator pred, pred1, hint;
Chris@16:      Unit begin, end;
Chris@16:      ActiveTail<Unit> *pfig, *ppfig;
Chris@16:      std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair;
Chris@16:      size_t pfig_size = 0;
Chris@16: 
Chris@16:      hint = tailMap_.begin();
Chris@16:      for(size_t i=0; i < leftEdges.size(); i++){
Chris@16:         begin = leftEdges[i].get(LOW); end = leftEdges[i].get(HIGH);
Chris@16:         succ = findAtNext(tailMap_, hint, begin); 
Chris@16:         pred = findAtNext(tailMap_, hint, end); 
Chris@16: 
Chris@16:         if(succ != tailMap_.end() && pred != tailMap_.end()){ //CASE-1//
Chris@16:            //join the corresponding active tails//
Chris@16:            pfig = succ->second; ppfig = pred->second;
Chris@16:            pfig_size = pfig->getPolyLineSize() + ppfig->getPolyLineSize();
Chris@16: 
Chris@16:            if(pfig_size >= vertexThreshold){
Chris@16:               size_t bsize = pfig->getPolyLineSize();
Chris@16:               size_t usize = ppfig->getPolyLineSize();
Chris@16: 
Chris@16:               if(usize+2 < vertexThreshold){
Chris@16:                  //cut-off the lower piece (succ1, succ) join (succ1, pred)//
Chris@16:                  succ1 = succ; --succ1;
Chris@16:                  assert((succ1 != tailMap_.end()) && 
Chris@16:                   ((succ->second)->getOtherActiveTail() == succ1->second));
Chris@16:                  closePartialSimplePolygon(currentX, succ1->second, succ->second);
Chris@16:                  tailPair = createActiveTailsAsPair<Unit>(currentX, succ1->first,
Chris@16:                      true, NULL, fractureHoles_);
Chris@16: 
Chris@16:                  //just update the succ1 with new ActiveTail<Unit>*//
Chris@16:                  succ1->second = tailPair.second;
Chris@16:                  ActiveTail<Unit>::joinChains(tailPair.first, pred->second, true,
Chris@16:                      outputPolygons_);
Chris@16:               }else if(bsize+2 < vertexThreshold){
Chris@16:                  //cut-off the upper piece () join ()//
Chris@16:                  pred1 = pred; ++pred1;
Chris@16:                  assert(pred1 != tailMap_.end() && 
Chris@16:                   ((pred1->second)->getOtherActiveTail() == pred->second));
Chris@16:                  closePartialSimplePolygon(currentX, pred->second, pred1->second);
Chris@16: 
Chris@16:                  //just update the pred1 with ActiveTail<Unit>* = pfig//
Chris@16:                  pred1->second = pfig;
Chris@16:                  pfig->pushCoordinate(currentX);
Chris@16:                  pfig->pushCoordinate(pred1->first);
Chris@16:               }else{ 
Chris@16:                  //cut both and create an left edge between (pred->first, succ1)//
Chris@16:                  succ1 = succ; --succ1; 
Chris@16:                  pred1 = pred; ++pred1;
Chris@16:                  assert(pred1 != tailMap_.end() && succ1 != tailMap_.end()); 
Chris@16:                  assert((pred1->second)->getOtherActiveTail() == pred->second);
Chris@16:                  assert((succ1->second)->getOtherActiveTail() == succ->second);
Chris@16: 
Chris@16:                  closePartialSimplePolygon(currentX, succ1->second, succ->second);
Chris@16:                  closePartialSimplePolygon(currentX, pred->second, pred1->second);
Chris@16: 
Chris@16:                  tailPair = createActiveTailsAsPair<Unit>(currentX, succ1->first,
Chris@16:                      true, NULL, fractureHoles_);
Chris@16:                  succ1->second = tailPair.second;
Chris@16:                  pred1->second = tailPair.first;
Chris@16:                  (tailPair.first)->pushCoordinate(pred1->first);
Chris@16:               }
Chris@16:            }else{
Chris@16:               //just join them with closing//
Chris@16:               pfig->pushCoordinate(currentX);
Chris@16:               ActiveTail<Unit>::joinChains(pfig, ppfig, true, outputPolygons_);
Chris@16:            }
Chris@16:            hint = pred; ++hint; 
Chris@16:            tailMap_.erase(succ); tailMap_.erase(pred);
Chris@16:         }else if(succ == tailMap_.end() && pred != tailMap_.end()){ //CASE-2//
Chris@16:            //succ is missing in the map, first insert it into the map//
Chris@16:            tailPair = createActiveTailsAsPair<Unit>(currentX, begin, true, NULL, 
Chris@16:                fractureHoles_);
Chris@16:            hint = pred; ++hint;
Chris@16:            hint = tailMap_.insert(hint, std::make_pair(begin, tailPair.second));
Chris@16: 
Chris@16:            pfig = pred->second;
Chris@16:            pfig_size = pfig->getPolyLineSize() + 2;
Chris@16:            if(pfig_size >= vertexThreshold){
Chris@16:               //cut-off piece from [pred, pred1] , add [begin, pred1]//
Chris@16:               pred1 = pred; ++pred1;
Chris@16:               assert((pred1 != tailMap_.end()) && 
Chris@16:                ((pred1->second)->getOtherActiveTail() == pred->second));
Chris@16:               closePartialSimplePolygon(currentX, pred->second, pred1->second);
Chris@16: 
Chris@16:               //update: we need left edge between (begin, pred1->first)//
Chris@16:               pred1->second = tailPair.first;
Chris@16:               (tailPair.first)->pushCoordinate(pred1->first);
Chris@16:            }else{
Chris@16:               //just join//
Chris@16:               ActiveTail<Unit>::joinChains(tailPair.first, pfig, 
Chris@16:                   true, outputPolygons_);
Chris@16:            }
Chris@16:            tailMap_.erase(pred);
Chris@16:         }else if(succ != tailMap_.end() && pred == tailMap_.end()){ //CASE-3//
Chris@16:             //pred is missing in the map, first insert it into the map//
Chris@16:             hint = succ; ++hint;
Chris@16:             hint = tailMap_.insert(hint, std::make_pair(end, (ActiveTail<Unit> *) NULL));
Chris@16:             pfig = succ->second;
Chris@16:             pfig_size = pfig->getPolyLineSize() + 2;
Chris@16:             if(pfig_size >= vertexThreshold){
Chris@16:                //this figure needs cutting here//
Chris@16:                succ1 = succ; --succ1;
Chris@16:                assert((succ1 != tailMap_.end()) &&
Chris@16:                   (succ1->second == pfig->getOtherActiveTail()));
Chris@16:                ppfig = succ1->second;
Chris@16:                closePartialSimplePolygon(currentX, ppfig, pfig);
Chris@16: 
Chris@16:                //update: we need a left edge between (succ1->first, end)//
Chris@16:                tailPair = createActiveTailsAsPair<Unit>(currentX, succ1->first,
Chris@16:                   true, NULL, fractureHoles_);
Chris@16:                succ1->second = tailPair.second;
Chris@16:                hint->second = tailPair.first;
Chris@16:                (tailPair.first)->pushCoordinate(end);
Chris@16:             }else{
Chris@16:                //no cutting needed//
Chris@16:                hint->second = pfig;
Chris@16:                pfig->pushCoordinate(currentX);
Chris@16:                pfig->pushCoordinate(end);
Chris@16:             }
Chris@16:             tailMap_.erase(succ);
Chris@16:         }else{
Chris@16:            //insert both pred and succ//
Chris@16:            insertNewLeftEdgeIntoTailMap(currentX, begin, end, hint);
Chris@16:         }
Chris@16:      }
Chris@16:   }
Chris@16: 
Chris@16:   template<bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
Chris@16:   updatePartialSimplePolygonsWithRightEdges(Unit currentX,
Chris@16:    const std::vector<interval_data<Unit> > &rightEdges, size_t vertexThreshold) 
Chris@16:    {
Chris@16:     
Chris@16:      typename std::map<Unit, ActiveTail<Unit>* >::iterator succ, pred, hint;
Chris@16:      std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair; 
Chris@16:      Unit begin, end;
Chris@16:      size_t i = 0;
Chris@16:      //If rightEdges is non-empty Then tailMap_ is non-empty //
Chris@16:      assert(rightEdges.empty() || !tailMap_.empty() );
Chris@16: 
Chris@16:      while( i < rightEdges.size() ){
Chris@16:         //find the interval in the tailMap which contains this interval// 
Chris@16:         pred = tailMap_.lower_bound(rightEdges[i].get(HIGH)); 
Chris@16:         assert(pred != tailMap_.end());
Chris@16:         succ = pred; --succ;
Chris@16:         assert(pred != succ);
Chris@16:         end =  pred->first; begin = succ->first;
Chris@16: 
Chris@16:         //we now have a [begin, end] //
Chris@16:         bool found_solid_opening = false;
Chris@16:         bool erase_succ = true, erase_pred = true;
Chris@16:         Unit solid_opening_begin = 0;
Chris@16:         Unit solid_opening_end = 0;
Chris@16:         size_t j = i+1;
Chris@16:         ActiveTail<Unit> *pfig = succ->second;
Chris@16:         ActiveTail<Unit> *ppfig = pred->second;
Chris@16:         size_t partial_fig_size = pfig->getPolyLineSize();
Chris@16:         //Invariant://
Chris@16:         assert(succ->second && (pfig)->getOtherActiveTail() == ppfig);
Chris@16: 
Chris@16:         hint = succ;
Chris@16:         Unit key = rightEdges[i].get(LOW);
Chris@16:         if(begin != key){
Chris@16:            found_solid_opening = true;
Chris@16:            solid_opening_begin = begin; solid_opening_end = key;
Chris@16:         }
Chris@16: 
Chris@16:         while(j < rightEdges.size() && rightEdges[j].get(HIGH) <= end){
Chris@16:            if(rightEdges[j-1].get(HIGH) != rightEdges[j].get(LOW)){
Chris@16:               if(!found_solid_opening){
Chris@16:                  found_solid_opening = true;
Chris@16:                  solid_opening_begin = rightEdges[j-1].get(HIGH); 
Chris@16:                  solid_opening_end = rightEdges[j].get(LOW);
Chris@16:               }else{
Chris@16:                  ++hint;
Chris@16:                  insertNewLeftEdgeIntoTailMap(currentX, 
Chris@16:                      rightEdges[j-1].get(HIGH), rightEdges[j].get(LOW), hint);
Chris@16:               }
Chris@16:            }
Chris@16:            j++;
Chris@16:         }
Chris@16: 
Chris@16:         //trailing edge//
Chris@16:         if(end != rightEdges[j-1].get(HIGH)){
Chris@16:            if(!found_solid_opening){
Chris@16:               found_solid_opening = true;
Chris@16:               solid_opening_begin = rightEdges[j-1].get(HIGH); solid_opening_end = end;
Chris@16:            }else{ 
Chris@16:               // a solid opening has been found already, we need to insert a new left 
Chris@16:               // between [rightEdges[j-1].get(HIGH), end]  
Chris@16:               Unit lbegin = rightEdges[j-1].get(HIGH);
Chris@16:               tailPair = createActiveTailsAsPair<Unit>(currentX, lbegin, true, NULL,
Chris@16:                   fractureHoles_);
Chris@16:               hint = tailMap_.insert(pred, std::make_pair(lbegin, tailPair.second));
Chris@16:               pred->second = tailPair.first;
Chris@16:               (tailPair.first)->pushCoordinate(end);
Chris@16:               erase_pred = false;
Chris@16:            }
Chris@16:         }
Chris@16: 
Chris@16:         size_t vertex_delta = ((begin != solid_opening_begin) && 
Chris@16:                (end != solid_opening_end)) ? 4 : 2;
Chris@16: 
Chris@16:         if(!found_solid_opening){
Chris@16:            //just close the figure, TODO: call closePartialPolygon//
Chris@16:            pfig->pushCoordinate(currentX);
Chris@16:            ActiveTail<Unit>::joinChains(pfig, ppfig, false, outputPolygons_);
Chris@16:            hint = pred; ++hint;
Chris@16:         }else if(partial_fig_size+vertex_delta >= vertexThreshold){
Chris@16:            //close the figure and add a pseudo left-edge//
Chris@16:            closePartialSimplePolygon(currentX, pfig, ppfig);
Chris@16:            assert(begin != solid_opening_begin || end != solid_opening_end);
Chris@16: 
Chris@16:            if(begin != solid_opening_begin && end != solid_opening_end){
Chris@16:                insertNewLeftEdgeIntoTailMap(currentX, solid_opening_begin, 
Chris@16:                      solid_opening_end, hint);
Chris@16:            }else if(begin == solid_opening_begin){
Chris@16:               //we just need to update the succ in the tailMap_//
Chris@16:               tailPair = createActiveTailsAsPair<Unit>(currentX, solid_opening_begin,
Chris@16:                   true, NULL, fractureHoles_);
Chris@16:               succ->second = tailPair.second;
Chris@16:               hint = succ; ++hint;
Chris@16:               hint = tailMap_.insert(pred, std::make_pair(solid_opening_end, 
Chris@16:                   tailPair.first));
Chris@16:               (tailPair.first)->pushCoordinate(solid_opening_end);
Chris@16:               erase_succ = false;
Chris@16:            }else{
Chris@16:               //we just need to update the pred in the tailMap_//
Chris@16:               tailPair = createActiveTailsAsPair<Unit>(currentX, solid_opening_begin,
Chris@16:                   true, NULL, fractureHoles_);
Chris@16:               hint = tailMap_.insert(pred, std::make_pair(solid_opening_begin,
Chris@16:                   tailPair.second));
Chris@16:               pred->second = tailPair.first;
Chris@16:               (tailPair.first)->pushCoordinate(solid_opening_end);
Chris@16:               erase_pred = false;
Chris@16:            }
Chris@16:         }else{
Chris@16:            //continue the figure (by adding at-most two new vertices)//
Chris@16:            if(begin != solid_opening_begin){
Chris@16:               pfig->pushCoordinate(currentX);
Chris@16:               pfig->pushCoordinate(solid_opening_begin);
Chris@16:               //insert solid_opening_begin//
Chris@16:               hint = succ; ++hint;
Chris@16:               hint = tailMap_.insert(hint, std::make_pair(solid_opening_begin, pfig));
Chris@16:            }else{
Chris@16:               erase_succ = false;
Chris@16:            }
Chris@16: 
Chris@16:            if(end != solid_opening_end){
Chris@16:               std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair = 
Chris@16:                createActiveTailsAsPair<Unit>(currentX, solid_opening_end, false, 
Chris@16:                      NULL, fractureHoles_);
Chris@16:               hint = pred; ++hint;
Chris@16:               hint = tailMap_.insert(hint, std::make_pair(solid_opening_end, 
Chris@16:                   tailPair.second));
Chris@16:               ActiveTail<Unit>::joinChains(tailPair.first, ppfig, false, 
Chris@16:                   outputPolygons_);
Chris@16:            }else{
Chris@16:               erase_pred = false;
Chris@16:            }
Chris@16:         }
Chris@16: 
Chris@16:         //Remove the pred and succ if necessary//
Chris@16:         if(erase_succ){
Chris@16:            tailMap_.erase(succ);
Chris@16:         }
Chris@16:         if(erase_pred){
Chris@16:            tailMap_.erase(pred);
Chris@16:         }
Chris@16:         i = j;
Chris@16:      }
Chris@16:  }
Chris@16: 
Chris@16:  // Maintains the following invariant:
Chris@16:  // a. All the partial polygons formed at any state can be closed 
Chris@16:  //    by a single edge.
Chris@16:  template<bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:  inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
Chris@16:  maintainPartialSimplePolygonInvariant(iterator& beginOutput, 
Chris@16:    iterator& endOutput, Unit currentX, const std::vector<interval_data<Unit> >& l, 
Chris@16:       const std::vector<interval_data<Unit> >& r, size_t vertexThreshold) {
Chris@16: 
Chris@16:       clearOutput_();
Chris@16:       if(!l.empty()){
Chris@16:          updatePartialSimplePolygonsWithLeftEdges(currentX, l, vertexThreshold);
Chris@16:       }
Chris@16: 
Chris@16:       if(!r.empty()){
Chris@16:          updatePartialSimplePolygonsWithRightEdges(currentX, r, vertexThreshold);
Chris@16:       }
Chris@16:       beginOutput = outputPolygons_.begin();
Chris@16:       endOutput = outputPolygons_.end();
Chris@16: 
Chris@16:   }
Chris@16:    
Chris@16:   //Process edges connects vertical input edges (right or left edges of figures) to horizontal edges stored as member
Chris@16:   //data of the scanline object.  It also creates now horizontal edges as needed to construct figures from edge data.
Chris@16:   //
Chris@16:   //There are only 12 geometric end cases where the scanline intersects a horizontal edge and even fewer unique 
Chris@16:   //actions to take:
Chris@16:   // 1. Solid on both sides of the vertical partition after the current position and space on both sides before
Chris@16:   //         ###|###          
Chris@16:   //         ###|###         
Chris@16:   //            |            
Chris@16:   //            |            
Chris@16:   //    This case does not need to be handled because there is no vertical edge at the current x coordinate.
Chris@16:   //
Chris@16:   // 2. Solid on both sides of the vertical partition before the current position and space on both sides after
Chris@16:   //            |            
Chris@16:   //            |            
Chris@16:   //         ###|###          
Chris@16:   //         ###|###         
Chris@16:   //    This case does not need to be handled because there is no vertical edge at the current x coordinate.
Chris@16:   //
Chris@16:   // 3. Solid on the left of the vertical partition after the current position and space elsewhere
Chris@16:   //         ###|          
Chris@16:   //         ###|         
Chris@16:   //            |            
Chris@16:   //            |     
Chris@16:   //    The horizontal edge from the left is found and turns upward because of the vertical right edge to become
Chris@16:   //    the currently active vertical edge.
Chris@16:   //
Chris@16:   // 4. Solid on the left of the vertical partion before the current position and space elsewhere
Chris@16:   //            |            
Chris@16:   //            |            
Chris@16:   //         ###| 
Chris@16:   //         ###|
Chris@16:   //    The horizontal edge from the left is found and joined to the currently active vertical edge.
Chris@16:   //
Chris@16:   // 5. Solid to the right above and below and solid to the left above current position.
Chris@16:   //         ###|###          
Chris@16:   //         ###|###         
Chris@16:   //            |###            
Chris@16:   //            |###            
Chris@16:   //    The horizontal edge from the left is found and joined to the currently active vertical edge,
Chris@16:   //    potentially closing a hole.
Chris@16:   //
Chris@16:   // 6. Solid on the left of the vertical partion before the current position and solid to the right above and below
Chris@16:   //            |###
Chris@16:   //            |###            
Chris@16:   //         ###|### 
Chris@16:   //         ###|###
Chris@16:   //    The horizontal edge from the left is found and turns upward because of the vertical right edge to become
Chris@16:   //    the currently active vertical edge.
Chris@16:   //
Chris@16:   // 7. Solid on the right of the vertical partition after the current position and space elsewhere
Chris@16:   //            |###          
Chris@16:   //            |###         
Chris@16:   //            |            
Chris@16:   //            |     
Chris@16:   //    Create two new ActiveTails, one is added to the horizontal edges and the other becomes the vertical currentTail
Chris@16:   //
Chris@16:   // 8. Solid on the right of the vertical partion before the current position and space elsewhere
Chris@16:   //            |            
Chris@16:   //            |            
Chris@16:   //            |### 
Chris@16:   //            |###
Chris@16:   //    The currentTail vertical edge turns right and is added to the horizontal edges data
Chris@16:   //
Chris@16:   // 9. Solid to the right above and solid to the left above and below current position.
Chris@16:   //         ###|###          
Chris@16:   //         ###|###         
Chris@16:   //         ###| 
Chris@16:   //         ###|
Chris@16:   //    The currentTail vertical edge turns right and is added to the horizontal edges data
Chris@16:   //
Chris@16:   // 10. Solid on the left of the vertical partion above and below the current position and solid to the right below
Chris@16:   //         ###| 
Chris@16:   //         ###|
Chris@16:   //         ###|### 
Chris@16:   //         ###|###
Chris@16:   //    Create two new ActiveTails, one is added to the horizontal edges data and the other becomes the vertical currentTail
Chris@16:   //
Chris@16:   // 11. Solid to the right above and solid to the left below current position.
Chris@16:   //            |### 
Chris@16:   //            |###
Chris@16:   //         ###| 
Chris@16:   //         ###|
Chris@16:   //    The currentTail vertical edge joins the horizontal edge from the left (may close a polygon)
Chris@16:   //    Create two new ActiveTails, one is added to the horizontal edges data and the other becomes the vertical currentTail
Chris@16:   //
Chris@16:   // 12. Solid on the left of the vertical partion above the current position and solid to the right below
Chris@16:   //         ###| 
Chris@16:   //         ###|
Chris@16:   //            |### 
Chris@16:   //            |###
Chris@16:   //    The currentTail vertical edge turns right and is added to the horizontal edges data.
Chris@16:   //    The horizontal edge from the left turns upward and becomes the currentTail vertical edge
Chris@16:   //
Chris@16:   template <bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
Chris@16:   processEdges(iterator& beginOutput, iterator& endOutput, 
Chris@16:                Unit currentX, std::vector<interval_data<Unit> >& leftEdges, 
Chris@16:                std::vector<interval_data<Unit> >& rightEdges,
Chris@16:                size_t vertexThreshold) {
Chris@16:     clearOutput_();
Chris@16:     typename std::map<Unit, ActiveTail<Unit>*>::iterator nextMapItr; 
Chris@16:     //foreach edge
Chris@16:     unsigned int leftIndex = 0;
Chris@16:     unsigned int rightIndex = 0;
Chris@16:     bool bottomAlreadyProcessed = false;
Chris@16:     ActiveTail<Unit>* currentTail = 0;
Chris@16:     const Unit UnitMax = (std::numeric_limits<Unit>::max)();
Chris@16: 
Chris@16:     if(vertexThreshold < (std::numeric_limits<size_t>::max)()){
Chris@16:       maintainPartialSimplePolygonInvariant(beginOutput, endOutput, currentX,
Chris@16:          leftEdges, rightEdges, vertexThreshold);
Chris@16:       return;
Chris@16:     }
Chris@16: 
Chris@16:     nextMapItr = tailMap_.begin();
Chris@16:     while(leftIndex < leftEdges.size() || rightIndex < rightEdges.size()) {
Chris@16:       interval_data<Unit>  edges[2] = {interval_data<Unit> (UnitMax, UnitMax), 
Chris@16:          interval_data<Unit> (UnitMax, UnitMax)};
Chris@16:       bool haveNextEdge = true;
Chris@16:       if(leftIndex < leftEdges.size())
Chris@16:         edges[0] = leftEdges[leftIndex];
Chris@16:       else
Chris@16:         haveNextEdge = false;
Chris@16:       if(rightIndex < rightEdges.size())
Chris@16:         edges[1] = rightEdges[rightIndex];
Chris@16:       else
Chris@16:         haveNextEdge = false;
Chris@16:       bool trailingEdge = edges[1].get(LOW) < edges[0].get(LOW);
Chris@16:       interval_data<Unit> & edge = edges[trailingEdge];
Chris@16:       interval_data<Unit> & nextEdge = edges[!trailingEdge];
Chris@16:       //process this edge
Chris@16:       if(!bottomAlreadyProcessed) {
Chris@16:         //assert currentTail = 0 
Chris@16: 
Chris@16:         //process the bottom end of this edge
Chris@16:         typename std::map<Unit, ActiveTail<Unit>*>::iterator thisMapItr = findAtNext(tailMap_, nextMapItr, edge.get(LOW));
Chris@16:         if(thisMapItr != tailMap_.end()) {
Chris@16:           //there is an edge in the map at the low end of this edge
Chris@16:           //it needs to turn upward and become the current tail
Chris@16:           ActiveTail<Unit>* tail = thisMapItr->second;
Chris@16:           if(currentTail) {
Chris@16:             //stitch currentTail into this tail
Chris@16:             currentTail = tail->addHole(currentTail, fractureHoles_);
Chris@16:             if(!fractureHoles_)
Chris@16:               currentTail->pushCoordinate(currentX);
Chris@16:           } else {
Chris@16:             currentTail = tail;
Chris@16:             currentTail->pushCoordinate(currentX);
Chris@16:           }
Chris@16:           //assert currentTail->getOrient() == VERTICAL
Chris@16:           nextMapItr = thisMapItr; //set nextMapItr to the next position after this one
Chris@16:           ++nextMapItr;
Chris@16:           //remove thisMapItr from the map
Chris@16:           tailMap_.erase(thisMapItr);
Chris@16:         } else {
Chris@16:           //there is no edge in the map at the low end of this edge
Chris@16:           //we need to create one and another one to be the current vertical tail
Chris@16:           //if this is a trailing edge then there is space to the right of the vertical edge
Chris@16:           //so pass the inverse of trailingEdge to indicate solid to the right
Chris@16:           std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair = 
Chris@16:             createActiveTailsAsPair(currentX, edge.get(LOW), !trailingEdge, currentTail, fractureHoles_);
Chris@16:           currentTail = tailPair.first;
Chris@16:           tailMap_.insert(nextMapItr, std::pair<Unit, ActiveTail<Unit>*>(edge.get(LOW), tailPair.second));
Chris@16:           // leave nextMapItr unchanged
Chris@16:         }
Chris@16: 
Chris@16:       }
Chris@16:       if(haveNextEdge && edge.get(HIGH) == nextEdge.get(LOW)) {
Chris@16:         //the top of this edge is equal to the bottom of the next edge, process them both
Chris@16:         bottomAlreadyProcessed = true;
Chris@16:         typename std::map<Unit, ActiveTail<Unit>*>::iterator thisMapItr = findAtNext(tailMap_, nextMapItr, edge.get(HIGH));
Chris@16:         if(thisMapItr == tailMap_.end()) //assert this should never happen
Chris@16:           return;
Chris@16:         if(trailingEdge) {
Chris@16:           //geometry at this position
Chris@16:           //   |##
Chris@16:           //   |##
Chris@16:           // -----
Chris@16:           // ##|
Chris@16:           // ##|
Chris@16:           //current tail should join thisMapItr tail
Chris@16:           ActiveTail<Unit>* tail = thisMapItr->second;
Chris@16:           //pass false because they are being joined because space is to the right and it will close a solid figure
Chris@16:           ActiveTail<Unit>::joinChains(currentTail, tail, false, outputPolygons_);
Chris@16:           //two new tails are created, the vertical becomes current tail, the horizontal becomes thisMapItr tail
Chris@16:           //pass true becuase they are created at the lower left corner of some solid
Chris@16:           //pass null because there is no hole pointer possible
Chris@16:           std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair = 
Chris@16:             createActiveTailsAsPair<Unit>(currentX, edge.get(HIGH), true, 0, fractureHoles_);
Chris@16:           currentTail = tailPair.first;
Chris@16:           thisMapItr->second = tailPair.second;
Chris@16:         } else {
Chris@16:           //geometry at this position
Chris@16:           // ##|
Chris@16:           // ##|
Chris@16:           // -----
Chris@16:           //   |##
Chris@16:           //   |##
Chris@16:           //current tail should turn right
Chris@16:           currentTail->pushCoordinate(edge.get(HIGH));
Chris@16:           //thisMapItr tail should turn up
Chris@16:           thisMapItr->second->pushCoordinate(currentX);
Chris@16:           //thisMapItr tail becomes current tail and current tail becomes thisMapItr tail
Chris@16:           std::swap(currentTail, thisMapItr->second);
Chris@16:         }
Chris@16:         nextMapItr = thisMapItr; //set nextMapItr to the next position after this one
Chris@16:         ++nextMapItr;
Chris@16:       } else {
Chris@16:         //there is a gap between the top of this edge and the bottom of the next, process the top of this edge
Chris@16:         bottomAlreadyProcessed = false;
Chris@16:         //process the top of this edge
Chris@16:         typename std::map<Unit, ActiveTail<Unit>*>::iterator thisMapItr = findAtNext(tailMap_, nextMapItr, edge.get(HIGH));
Chris@16:         if(thisMapItr != tailMap_.end()) {
Chris@16:           //thisMapItr is pointing to a horizontal edge in the map at the top of this vertical edge
Chris@16:           //we need to join them and potentially close a figure
Chris@16:           //assert currentTail != 0
Chris@16:           ActiveTail<Unit>* tail = thisMapItr->second;
Chris@16:           //pass the opositve of trailing edge to mean that they are joined because of solid to the right
Chris@16:           currentTail = ActiveTail<Unit>::joinChains(currentTail, tail, !trailingEdge, outputPolygons_);
Chris@16:           nextMapItr = thisMapItr; //set nextMapItr to the next position after this one
Chris@16:           ++nextMapItr;
Chris@16:           if(currentTail) { //figure is not closed//
Chris@16:             Unit nextItrY = UnitMax;
Chris@16:             if(nextMapItr != tailMap_.end()) {
Chris@16:               nextItrY = nextMapItr->first;
Chris@16:             }
Chris@16:             //for it to be a hole this must have been a left edge
Chris@16:             Unit leftY = UnitMax;
Chris@16:             if(leftIndex + 1 < leftEdges.size())
Chris@16:               leftY = leftEdges[leftIndex+1].get(LOW);
Chris@16:             Unit rightY = nextEdge.get(LOW);
Chris@16:             if(!haveNextEdge || (nextItrY < leftY && nextItrY < rightY)) {
Chris@16:               //we need to add it to the next edge above it in the map
Chris@16:               tail = nextMapItr->second;
Chris@16:               tail = tail->addHole(currentTail, fractureHoles_);
Chris@16:               if(fractureHoles_) {
Chris@16:                 //some small additional work stitching in the filament
Chris@16:                 tail->pushCoordinate(nextItrY);
Chris@16:                 nextMapItr->second = tail;
Chris@16:               }
Chris@16:               //set current tail to null
Chris@16:               currentTail = 0;
Chris@16:             }
Chris@16:           }  
Chris@16:           //delete thisMapItr from the map
Chris@16:           tailMap_.erase(thisMapItr);
Chris@16:         } else {
Chris@16:           //currentTail must turn right and be added into the map
Chris@16:           currentTail->pushCoordinate(edge.get(HIGH));
Chris@16:           //assert currentTail->getOrient() == HORIZONTAL
Chris@16:           tailMap_.insert(nextMapItr, std::pair<Unit, ActiveTail<Unit>*>(edge.get(HIGH), currentTail));
Chris@16:           //set currentTail to null
Chris@16:           currentTail = 0;
Chris@16:           //leave nextMapItr unchanged, it is still next
Chris@16:         }
Chris@16:       }
Chris@16:  
Chris@16:       //increment index
Chris@16:       leftIndex += !trailingEdge;
Chris@16:       rightIndex += trailingEdge;
Chris@16:     } //end while
Chris@16:     beginOutput = outputPolygons_.begin();
Chris@16:     endOutput = outputPolygons_.end();
Chris@16:   } //end function
Chris@16: 
Chris@16:   template<bool orientT, typename Unit, typename polygon_concept_type>
Chris@16:   inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::clearOutput_() {
Chris@16:     for(std::size_t i = 0; i < outputPolygons_.size(); ++i) {
Chris@16:       ActiveTail<Unit>* at1 = outputPolygons_[i].yield();
Chris@16:       const std::list<ActiveTail<Unit>*>& holes = at1->getHoles();
Chris@16:       for(typename std::list<ActiveTail<Unit>*>::const_iterator litr = holes.begin(); litr != holes.end(); ++litr) {
Chris@16:         //delete the hole
Chris@16:         (*litr)->destroyContents();
Chris@16:         destroyActiveTail((*litr)->getOtherActiveTail());
Chris@16:         destroyActiveTail((*litr));
Chris@16:       }
Chris@16:       //delete the polygon
Chris@16:       at1->destroyContents();
Chris@16:       //at2 contents are the same as at1, so it should not destroy them
Chris@16:       destroyActiveTail((at1)->getOtherActiveTail());
Chris@16:       destroyActiveTail(at1);
Chris@16:     }
Chris@16:     outputPolygons_.clear();
Chris@16:   }
Chris@16: 
Chris@16: } //polygon_formation namespace
Chris@16: 
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct geometry_concept<polygon_formation::PolyLinePolygonWithHolesData<orientT, Unit> > {
Chris@16:     typedef polygon_90_with_holes_concept type;
Chris@16:   };
Chris@16: 
Chris@16:   template <bool orientT, typename Unit>
Chris@16:   struct geometry_concept<polygon_formation::PolyLineHoleData<orientT, Unit> > {
Chris@16:     typedef polygon_90_concept type;
Chris@16:   };
Chris@16: 
Chris@16:   //public API to access polygon formation algorithm
Chris@16:   template <typename output_container, typename iterator_type, typename concept_type>
Chris@16:   unsigned int get_polygons(output_container& container, 
Chris@16:       iterator_type begin, iterator_type end, orientation_2d orient, 
Chris@16:       bool fracture_holes, concept_type, 
Chris@16:       size_t sliceThreshold = (std::numeric_limits<size_t>::max)() ) {
Chris@16:     typedef typename output_container::value_type polygon_type;
Chris@16:     typedef typename std::iterator_traits<iterator_type>::value_type::first_type coordinate_type;
Chris@16:     polygon_type poly;
Chris@16:     unsigned int countPolygons = 0;
Chris@16:     typedef typename geometry_concept<polygon_type>::type polygon_concept_type;
Chris@16:     polygon_formation::ScanLineToPolygonItrs<true, coordinate_type, polygon_concept_type> scanlineToPolygonItrsV(fracture_holes);
Chris@16:     polygon_formation::ScanLineToPolygonItrs<false, coordinate_type, polygon_concept_type> scanlineToPolygonItrsH(fracture_holes);
Chris@16:     std::vector<interval_data<coordinate_type> > leftEdges;
Chris@16:     std::vector<interval_data<coordinate_type> > rightEdges;
Chris@16:     coordinate_type prevPos = (std::numeric_limits<coordinate_type>::max)();
Chris@16:     coordinate_type prevY = (std::numeric_limits<coordinate_type>::max)();
Chris@16:     int count = 0;
Chris@16:     for(iterator_type itr = begin;
Chris@16:         itr != end; ++ itr) {
Chris@16:       coordinate_type pos = (*itr).first;
Chris@16:       if(pos != prevPos) {
Chris@16:         if(orient == VERTICAL) {
Chris@16:           typename polygon_formation::ScanLineToPolygonItrs<true, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
Chris@16:            scanlineToPolygonItrsV.processEdges(itrPoly, itrPolyEnd, prevPos, 
Chris@16:                leftEdges, rightEdges, sliceThreshold);
Chris@16:           for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
Chris@16:             ++countPolygons;
Chris@16:             assign(poly, *itrPoly);
Chris@16:             container.insert(container.end(), poly);
Chris@16:           }
Chris@16:         } else {
Chris@16:           typename polygon_formation::ScanLineToPolygonItrs<false, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
Chris@16:           scanlineToPolygonItrsH.processEdges(itrPoly, itrPolyEnd, prevPos, 
Chris@16:                leftEdges, rightEdges, sliceThreshold);
Chris@16:           for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
Chris@16:             ++countPolygons;
Chris@16:             assign(poly, *itrPoly);
Chris@16:             container.insert(container.end(), poly);
Chris@16:           }
Chris@16:         }
Chris@16:         leftEdges.clear();
Chris@16:         rightEdges.clear();
Chris@16:         prevPos = pos;
Chris@16:         prevY = (*itr).second.first;
Chris@16:         count = (*itr).second.second;
Chris@16:         continue;
Chris@16:       }
Chris@16:       coordinate_type y = (*itr).second.first;
Chris@16:       if(count != 0 && y != prevY) {
Chris@16:         std::pair<interval_data<coordinate_type>, int> element(interval_data<coordinate_type>(prevY, y), count);
Chris@16:         if(element.second == 1) {
Chris@16:           if(leftEdges.size() && leftEdges.back().high() == element.first.low()) {
Chris@16:             encompass(leftEdges.back(), element.first);
Chris@16:           } else {
Chris@16:             leftEdges.push_back(element.first);
Chris@16:           }
Chris@16:         } else {
Chris@16:           if(rightEdges.size() && rightEdges.back().high() == element.first.low()) {
Chris@16:             encompass(rightEdges.back(), element.first);
Chris@16:           } else {
Chris@16:             rightEdges.push_back(element.first);
Chris@16:           }
Chris@16:         }
Chris@16: 
Chris@16:       }
Chris@16:       prevY = y;
Chris@16:       count += (*itr).second.second;
Chris@16:     }
Chris@16:     if(orient == VERTICAL) {
Chris@16:       typename polygon_formation::ScanLineToPolygonItrs<true, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
Chris@16:       scanlineToPolygonItrsV.processEdges(itrPoly, itrPolyEnd, prevPos, leftEdges, rightEdges, sliceThreshold);
Chris@16:       for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
Chris@16:         ++countPolygons;
Chris@16:         assign(poly, *itrPoly);
Chris@16:         container.insert(container.end(), poly);
Chris@16:       }
Chris@16:     } else {
Chris@16:       typename polygon_formation::ScanLineToPolygonItrs<false, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
Chris@16:       scanlineToPolygonItrsH.processEdges(itrPoly, itrPolyEnd, prevPos, leftEdges, rightEdges,  sliceThreshold);
Chris@16: 
Chris@16:       for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
Chris@16:         ++countPolygons;
Chris@16:         assign(poly, *itrPoly);
Chris@16:         container.insert(container.end(), poly);
Chris@16:       }
Chris@16:     }
Chris@16:     return countPolygons;
Chris@16:   }
Chris@16: 
Chris@16: }
Chris@16: }
Chris@16: #endif