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android / platform / external / boost / 077d563efdb280a3d144892e2d0ca01e6a49f454 / . / boost / polygon / detail / polygon_formation.hpp
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/*
Copyright 2008 Intel Corporation
Use, modification and distribution are subject to the Boost Software License,
Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
http://www.boost.org/LICENSE_1_0.txt).
*/
#ifndef BOOST_POLYGON_POLYGON_FORMATION_HPP
#define BOOST_POLYGON_POLYGON_FORMATION_HPP
namespace boost { namespace polygon{
namespace polygon_formation {
/*
* End has two states, HEAD and TAIL as is represented by a bool
*/
typedef bool End;
/*
* HEAD End is represented as false because it is the lesser state
*/
const End HEAD = false;
/*
* TAIL End is represented by true because TAIL comes after head and 1 after 0
*/
const End TAIL = true;
/*
* 2D turning direction, left and right sides (is a boolean value since it has two states.)
*/
typedef bool Side;
/*
* LEFT Side is 0 because we inuitively think left to right; left < right
*/
const Side LEFT = false;
/*
* RIGHT Side is 1 so that right > left
*/
const Side RIGHT = true;
/*
* The PolyLine class is data storage and services for building and representing partial polygons.
* As the polyline is added to it extends its storage to accomodate the data.
* PolyLines can be joined head-to-head/head-to-tail when it is determined that two polylines are
* part of the same polygon.
* PolyLines keep state information about what orientation their incomplete head and tail geometry have,
* which side of the polyline is solid and whether the polyline is joined head-to-head and tail-to-head.
* PolyLines have nothing whatsoever to do with holes.
* It may be valuable to collect a histogram of PolyLine lengths used by an algorithm on its typical data
* sets and tune the allocation of the initial vector of coordinate data to be greater than or equal to
* the mean, median, mode, or mean plus some number of standard deviation, or just generally large enough
* to prevent too much unnecesary reallocations, but not too big that it wastes a lot of memory and degrades cache
* performance.
*/
template <typename Unit>
class PolyLine {
private:
//data
/*
* ptdata_ a vector of coordiantes
* if VERTICAL_HEAD, first coordiante is an X
* else first coordinate is a Y
*/
std::vector<Unit> ptdata_;
/*
* head and tail points to other polylines before and after this in a chain
*/
PolyLine* headp_;
PolyLine* tailp_;
/*
* state bitmask
* bit zero is orientation, 0 H, 1 V
* bit 1 is head connectivity, 0 for head, 1 for tail
* bit 2 is tail connectivity, 0 for head, 1 for tail
* bit 3 is solid to left of PolyLine when 1, right when 0
*/
int state_;
public:
/*
* default constructor (for preallocation)
*/
PolyLine();
/*
* constructor that takes the orientation, coordiante and side to which there is solid
*/
PolyLine(orientation_2d orient, Unit coord, Side side);
//copy constructor
PolyLine(const PolyLine& pline);
//destructor
~PolyLine();
//assignment operator
PolyLine& operator=(const PolyLine& that);
//equivalence operator
bool operator==(const PolyLine& b) const;
/*
* valid PolyLine (only default constructed polylines are invalid.)
*/
bool isValid() const;
/*
* Orientation of Head
*/
orientation_2d headOrient() const;
/*
* returns true if first coordinate is an X value (first segment is vertical)
*/
bool verticalHead() const;
/*
* returns the orientation_2d fo the tail
*/
orientation_2d tailOrient() const;
/*
* returns true if last coordinate is an X value (last segment is vertical)
*/
bool verticalTail() const;
/*
* retrun true if PolyLine has odd number of coordiantes
*/
bool oddLength() const;
/*
* retrun the End of the other polyline that the specified end of this polyline is connected to
*/
End endConnectivity(End end) const;
/*
* retrun true if the head of this polyline is connect to the tail of a polyline
*/
bool headToTail() const;
/*
* retrun true if the head of this polyline is connect to the head of a polyline
*/
bool headToHead() const;
/*
* retrun true if the tail of this polyline is connect to the tail of a polyline
*/
bool tailToTail() const;
/*
* retrun true if the tail of this polyline is connect to the head of a polyline
*/
bool tailToHead() const;
/*
* retrun the side on which there is solid for this polyline
*/
Side solidSide() const;
/*
* retrun true if there is solid to the right of this polyline
*/
bool solidToRight() const;
/*
* returns true if the polyline tail is not connected
*/
bool active() const;
/*
* adds a coordinate value to the end of the polyline changing the tail orientation
*/
PolyLine& pushCoordinate(Unit coord);
/*
* removes a coordinate value at the end of the polyline changing the tail orientation
*/
PolyLine& popCoordinate();
/*
* extends the tail of the polyline to include the point, changing orientation if needed
*/
PolyLine& pushPoint(const point_data<Unit>& point);
/*
* changes the last coordinate of the tail of the polyline by the amount of the delta
*/
PolyLine& extendTail(Unit delta);
/*
* join thisEnd of this polyline to that polyline's end
*/
PolyLine& joinTo(End thisEnd, PolyLine& that, End end);
/*
* join an end of this polyline to the tail of that polyline
*/
PolyLine& joinToTail(PolyLine& that, End end);
/*
* join an end of this polyline to the head of that polyline
*/
PolyLine& joinToHead(PolyLine& that, End end);
/*
* join the head of this polyline to the head of that polyline
*/
//join this to that in the given way
PolyLine& joinHeadToHead(PolyLine& that);
/*
* join the head of this polyline to the tail of that polyline
*/
PolyLine& joinHeadToTail(PolyLine& that);
/*
* join the tail of this polyline to the head of that polyline
*/
PolyLine& joinTailToHead(PolyLine& that);
/*
* join the tail of this polyline to the tail of that polyline
*/
PolyLine& joinTailToTail(PolyLine& that);
/*
* dissconnect the tail at the end of the polygon
*/
PolyLine& disconnectTails();
/*
* get the coordinate at one end of this polyline, by default the tail end
*/
Unit getEndCoord(End end = TAIL) const;
/*
* get the point on the polyline at the given index (polylines have the same number of coordinates as points
*/
point_data<Unit> getPoint(unsigned int index) const;
/*
* get the point on one end of the polyline, by default the tail
*/
point_data<Unit> getEndPoint(End end = TAIL) const;
/*
* get the orientation of a segment by index
*/
orientation_2d segmentOrient(unsigned int index = 0) const;
/*
* get a coordinate by index using the square bracket operator
*/
Unit operator[] (unsigned int index) const;
/*
* get the number of segments/points/coordinates in the polyline
*/
unsigned int numSegments() const;
/*
* get the pointer to the next polyline at one end of this
*/
PolyLine* next(End end) const;
/*
* write out coordinates of this and all attached polylines to a single vector
*/
PolyLine* writeOut(std::vector<Unit>& outVec, End startEnd = TAIL) const;
private:
//methods
PolyLine& joinTo_(End thisEnd, PolyLine& that, End end);
};
//forward declaration
template<bool orientT, typename Unit>
class PolyLinePolygonData;
//forward declaration
template<bool orientT, typename Unit>
class PolyLinePolygonWithHolesData;
/*
* ActiveTail represents an edge of an incomplete polygon.
*
* An ActiveTail object is the active tail end of a polyline object, which may (should) be the attached to
* a chain of polyline objects through a pointer. The ActiveTail class provides an abstraction between
* and algorithm that builds polygons and the PolyLine data representation of incomplete polygons that are
* being built. It does this by providing an iterface to access the information about the last edge at the
* tail of the PolyLine it is associated with. To a polygon constructing algorithm, an ActiveTail is a floating
* edge of an incomplete polygon and has an orientation and coordinate value, as well as knowing which side of
* that edge is supposed to be solid or space. Any incomplete polygon will have two active tails. Active tails
* may be joined together to merge two incomplete polygons into a larger incomplete polygon. If two active tails
* that are to be merged are the oppositve ends of the same incomplete polygon that indicates that the polygon
* has been closed and is complete. The active tail keeps a pointer to the other active tail of its incomplete
* polygon so that it is easy to check this condition. These pointers are updated when active tails are joined.
* The active tail also keeps a list of pointers to active tail objects that serve as handles to closed holes. In
* this way a hole can be associated to another incomplete polygon, which will eventually be its enclosing shell,
* or reassociate the hole to another incomplete polygon in the case that it become a hole itself. Alternately,
* the active tail may add a filiment to stitch a hole into a shell and "fracture" the hole out of the interior
* of a polygon. The active tail maintains a static output buffer to temporarily write polygon data to when
* it outputs a figure so that outputting a polygon does not require the allocation of a temporary buffer. This
* static buffer should be destroyed whenever the program determines that it won't need it anymore and would prefer to
* release the memory it has allocated back to the system.
*/
template <typename Unit>
class ActiveTail {
private:
//data
PolyLine<Unit>* tailp_;
ActiveTail *otherTailp_;
std::list<ActiveTail*> holesList_;
public:
/*
* iterator over coordinates of the figure
*/
class iterator {
private:
const PolyLine<Unit>* pLine_;
const PolyLine<Unit>* pLineEnd_;
unsigned int index_;
unsigned int indexEnd_;
End startEnd_;
public:
inline iterator() : pLine_(), pLineEnd_(), index_(), indexEnd_(), startEnd_() {}
inline iterator(const ActiveTail* at, bool isHole, orientation_2d orient) :
pLine_(), pLineEnd_(), index_(), indexEnd_(), startEnd_() {
//if it is a hole and orientation is vertical or it is not a hole and orientation is horizontal
//we want to use this active tail, otherwise we want to use the other active tail
startEnd_ = TAIL;
if(!isHole ^ (orient == HORIZONTAL)) {
//switch winding direction
at = at->getOtherActiveTail();
}
//now we have the right winding direction
//if it is horizontal we need to skip the first element
pLine_ = at->getTail();
index_ = at->getTail()->numSegments() - 1;
if((at->getOrient() == HORIZONTAL) ^ (orient == HORIZONTAL)) {
pLineEnd_ = at->getTail();
indexEnd_ = pLineEnd_->numSegments() - 1;
if(index_ == 0) {
pLine_ = at->getTail()->next(HEAD);
if(at->getTail()->endConnectivity(HEAD) == TAIL) {
index_ = pLine_->numSegments() -1;
} else {
startEnd_ = HEAD;
index_ = 0;
}
} else { --index_; }
} else {
pLineEnd_ = at->getOtherActiveTail()->getTail();
indexEnd_ = pLineEnd_->numSegments() - 1;
}
at->getTail()->joinTailToTail(*(at->getOtherActiveTail()->getTail()));
}
//use bitwise copy and assign provided by the compiler
inline iterator& operator++() {
if(pLine_ == pLineEnd_ && index_ == indexEnd_) {
pLine_ = 0;
index_ = 0;
return *this;
}
if(startEnd_ == HEAD) {
++index_;
if(index_ == pLine_->numSegments()) {
End end = pLine_->endConnectivity(TAIL);
pLine_ = pLine_->next(TAIL);
if(end == TAIL) {
startEnd_ = TAIL;
index_ = pLine_->numSegments() -1;
} else {
index_ = 0;
}
}
} else {
if(index_ == 0) {
End end = pLine_->endConnectivity(HEAD);
pLine_ = pLine_->next(HEAD);
if(end == TAIL) {
index_ = pLine_->numSegments() -1;
} else {
startEnd_ = HEAD;
index_ = 0;
}
} else {
--index_;
}
}
return *this;
}
inline const iterator operator++(int) {
iterator tmp(*this);
++(*this);
return tmp;
}
inline bool operator==(const iterator& that) const {
return pLine_ == that.pLine_ && index_ == that.index_;
}
inline bool operator!=(const iterator& that) const {
return pLine_ != that.pLine_ || index_ != that.index_;
}
inline Unit operator*() { return (*pLine_)[index_]; }
};
/*
* iterator over holes contained within the figure
*/
typedef typename std::list<ActiveTail*>::const_iterator iteratorHoles;
//default constructor
ActiveTail();
//constructor
ActiveTail(orientation_2d orient, Unit coord, Side solidToRight, ActiveTail* otherTailp);
//constructor
ActiveTail(PolyLine<Unit>* active, ActiveTail* otherTailp);
//copy constructor
ActiveTail(const ActiveTail& that);
//destructor
~ActiveTail();
//assignment operator
ActiveTail& operator=(const ActiveTail& that);
//equivalence operator
bool operator==(const ActiveTail& b) const;
/*
* comparison operators, ActiveTail objects are sortable by geometry
*/
bool operator<(const ActiveTail& b) const;
bool operator<=(const ActiveTail& b) const;
bool operator>(const ActiveTail& b) const;
bool operator>=(const ActiveTail& b) const;
/*
* get the pointer to the polyline that this is an active tail of
*/
PolyLine<Unit>* getTail() const;
/*
* get the pointer to the polyline at the other end of the chain
*/
PolyLine<Unit>* getOtherTail() const;
/*
* get the pointer to the activetail at the other end of the chain
*/
ActiveTail* getOtherActiveTail() const;
/*
* test if another active tail is the other end of the chain
*/
bool isOtherTail(const ActiveTail& b);
/*
* update this end of chain pointer to new polyline
*/
ActiveTail& updateTail(PolyLine<Unit>* newTail);
/*
* associate a hole to this active tail by the specified policy
*/
ActiveTail* addHole(ActiveTail* hole, bool fractureHoles);
/*
* get the list of holes
*/
const std::list<ActiveTail*>& getHoles() const;
/*
* copy holes from that to this
*/
void copyHoles(ActiveTail& that);
/*
* find out if solid to right
*/
bool solidToRight() const;
/*
* get coordinate (getCoord and getCoordinate are aliases for eachother)
*/
Unit getCoord() const;
Unit getCoordinate() const;
/*
* get the tail orientation
*/
orientation_2d getOrient() const;
/*
* add a coordinate to the polygon at this active tail end, properly handle degenerate edges by removing redundant coordinate
*/
void pushCoordinate(Unit coord);
/*
* write the figure that this active tail points to out to the temp buffer
*/
void writeOutFigure(std::vector<Unit>& outVec, bool isHole = false) const;
/*
* write the figure that this active tail points to out through iterators
*/
void writeOutFigureItrs(iterator& beginOut, iterator& endOut, bool isHole = false, orientation_2d orient = VERTICAL) const;
iterator begin(bool isHole, orientation_2d orient) const;
iterator end() const;
/*
* write the holes that this active tail points to out through iterators
*/
void writeOutFigureHoleItrs(iteratorHoles& beginOut, iteratorHoles& endOut) const;
iteratorHoles beginHoles() const;
iteratorHoles endHoles() const;
/*
* joins the two chains that the two active tail tails are ends of
* checks for closure of figure and writes out polygons appropriately
* returns a handle to a hole if one is closed
*/
static ActiveTail* joinChains(ActiveTail* at1, ActiveTail* at2, bool solid, std::vector<Unit>& outBufferTmp);
template <typename PolygonT>
static ActiveTail* joinChains(ActiveTail* at1, ActiveTail* at2, bool solid, typename std::vector<PolygonT>& outBufferTmp);
/*
* deallocate temp buffer
*/
static void destroyOutBuffer();
/*
* deallocate all polygon data this active tail points to (deep delete, call only from one of a pair of active tails)
*/
void destroyContents();
};
/* allocate a polyline object */
template <typename Unit>
PolyLine<Unit>* createPolyLine(orientation_2d orient, Unit coord, Side side);
/* deallocate a polyline object */
template <typename Unit>
void destroyPolyLine(PolyLine<Unit>* pLine);
/* allocate an activetail object */
template <typename Unit>
ActiveTail<Unit>* createActiveTail();
/* deallocate an activetail object */
template <typename Unit>
void destroyActiveTail(ActiveTail<Unit>* aTail);
template<bool orientT, typename Unit>
class PolyLineHoleData {
private:
ActiveTail<Unit>* p_;
public:
typedef Unit coordinate_type;
typedef typename ActiveTail<Unit>::iterator compact_iterator_type;
typedef iterator_compact_to_points<compact_iterator_type, point_data<coordinate_type> > iterator_type;
inline PolyLineHoleData() : p_(0) {}
inline PolyLineHoleData(ActiveTail<Unit>* p) : p_(p) {}
//use default copy and assign
inline compact_iterator_type begin_compact() const { return p_->begin(true, (orientT ? VERTICAL : HORIZONTAL)); }
inline compact_iterator_type end_compact() const { return p_->end(); }
inline iterator_type begin() const { return iterator_type(begin_compact(), end_compact()); }
inline iterator_type end() const { return iterator_type(end_compact(), end_compact()); }
inline std::size_t size() const { return 0; }
inline ActiveTail<Unit>* yield() { return p_; }
template<class iT>
inline PolyLineHoleData& set(iT inputBegin, iT inputEnd) {
return *this;
}
template<class iT>
inline PolyLineHoleData& set_compact(iT inputBegin, iT inputEnd) {
return *this;
}
};
template<bool orientT, typename Unit>
class PolyLinePolygonWithHolesData {
private:
ActiveTail<Unit>* p_;
public:
typedef Unit coordinate_type;
typedef typename ActiveTail<Unit>::iterator compact_iterator_type;
typedef iterator_compact_to_points<compact_iterator_type, point_data<coordinate_type> > iterator_type;
typedef PolyLineHoleData<orientT, Unit> hole_type;
typedef typename coordinate_traits<Unit>::area_type area_type;
class iteratorHoles {
private:
typename ActiveTail<Unit>::iteratorHoles itr_;
public:
inline iteratorHoles() : itr_() {}
inline iteratorHoles(typename ActiveTail<Unit>::iteratorHoles itr) : itr_(itr) {}
//use bitwise copy and assign provided by the compiler
inline iteratorHoles& operator++() {
++itr_;
return *this;
}
inline const iteratorHoles operator++(int) {
iteratorHoles tmp(*this);
++(*this);
return tmp;
}
inline bool operator==(const iteratorHoles& that) const {
return itr_ == that.itr_;
}
inline bool operator!=(const iteratorHoles& that) const {
return itr_ != that.itr_;
}
inline PolyLineHoleData<orientT, Unit> operator*() { return PolyLineHoleData<orientT, Unit>(*itr_);}
};
typedef iteratorHoles iterator_holes_type;
inline PolyLinePolygonWithHolesData() : p_(0) {}
inline PolyLinePolygonWithHolesData(ActiveTail<Unit>* p) : p_(p) {}
//use default copy and assign
inline compact_iterator_type begin_compact() const { return p_->begin(false, (orientT ? VERTICAL : HORIZONTAL)); }
inline compact_iterator_type end_compact() const { return p_->end(); }
inline iterator_type begin() const { return iterator_type(begin_compact(), end_compact()); }
inline iterator_type end() const { return iterator_type(end_compact(), end_compact()); }
inline iteratorHoles begin_holes() const { return iteratorHoles(p_->beginHoles()); }
inline iteratorHoles end_holes() const { return iteratorHoles(p_->endHoles()); }
inline ActiveTail<Unit>* yield() { return p_; }
//stub out these four required functions that will not be used but are needed for the interface
inline std::size_t size_holes() const { return 0; }
inline std::size_t size() const { return 0; }
template<class iT>
inline PolyLinePolygonWithHolesData& set(iT inputBegin, iT inputEnd) {
return *this;
}
template<class iT>
inline PolyLinePolygonWithHolesData& set_compact(iT inputBegin, iT inputEnd) {
return *this;
}
// initialize a polygon from x,y values, it is assumed that the first is an x
// and that the input is a well behaved polygon
template<class iT>
inline PolyLinePolygonWithHolesData& set_holes(iT inputBegin, iT inputEnd) {
return *this;
}
};
template <bool orientT, typename Unit, typename polygon_concept_type>
struct PolyLineType { };
template <bool orientT, typename Unit>
struct PolyLineType<orientT, Unit, polygon_90_with_holes_concept> { typedef PolyLinePolygonWithHolesData<orientT, Unit> type; };
template <bool orientT, typename Unit>
struct PolyLineType<orientT, Unit, polygon_45_with_holes_concept> { typedef PolyLinePolygonWithHolesData<orientT, Unit> type; };
template <bool orientT, typename Unit>
struct PolyLineType<orientT, Unit, polygon_with_holes_concept> { typedef PolyLinePolygonWithHolesData<orientT, Unit> type; };
template <bool orientT, typename Unit>
struct PolyLineType<orientT, Unit, polygon_90_concept> { typedef PolyLineHoleData<orientT, Unit> type; };
template <bool orientT, typename Unit>
struct PolyLineType<orientT, Unit, polygon_45_concept> { typedef PolyLineHoleData<orientT, Unit> type; };
template <bool orientT, typename Unit>
struct PolyLineType<orientT, Unit, polygon_concept> { typedef PolyLineHoleData<orientT, Unit> type; };
template <bool orientT, typename Unit, typename polygon_concept_type>
class ScanLineToPolygonItrs {
private:
std::map<Unit, ActiveTail<Unit>*> tailMap_;
typedef typename PolyLineType<orientT, Unit, polygon_concept_type>::type PolyLinePolygonData;
std::vector<PolyLinePolygonData> outputPolygons_;
bool fractureHoles_;
public:
typedef typename std::vector<PolyLinePolygonData>::iterator iterator;
inline ScanLineToPolygonItrs() : tailMap_(), outputPolygons_(), fractureHoles_(false) {}
/* construct a scanline with the proper offsets, protocol and options */
inline ScanLineToPolygonItrs(bool fractureHoles) : tailMap_(), outputPolygons_(), fractureHoles_(fractureHoles) {}
~ScanLineToPolygonItrs() { clearOutput_(); }
/* process all vertical edges, left and right, at a unique x coordinate, edges must be sorted low to high */
void processEdges(iterator& beginOutput, iterator& endOutput,
Unit currentX, std::vector<interval_data<Unit> >& leftEdges,
std::vector<interval_data<Unit> >& rightEdges);
private:
void clearOutput_();
};
/*
* ScanLine does all the work of stitching together polygons from incoming vertical edges
*/
// template <typename Unit, typename polygon_concept_type>
// class ScanLineToPolygons {
// private:
// ScanLineToPolygonItrs<true, Unit> scanline_;
// public:
// inline ScanLineToPolygons() : scanline_() {}
// /* construct a scanline with the proper offsets, protocol and options */
// inline ScanLineToPolygons(bool fractureHoles) : scanline_(fractureHoles) {}
// /* process all vertical edges, left and right, at a unique x coordinate, edges must be sorted low to high */
// inline void processEdges(std::vector<Unit>& outBufferTmp, Unit currentX, std::vector<interval_data<Unit> >& leftEdges,
// std::vector<interval_data<Unit> >& rightEdges) {
// typename ScanLineToPolygonItrs<true, Unit>::iterator itr, endItr;
// scanline_.processEdges(itr, endItr, currentX, leftEdges, rightEdges);
// //copy data into outBufferTmp
// while(itr != endItr) {
// typename PolyLinePolygonData<true, Unit>::iterator pditr;
// outBufferTmp.push_back(0);
// unsigned int sizeIndex = outBufferTmp.size() - 1;
// int count = 0;
// for(pditr = (*itr).begin(); pditr != (*itr).end(); ++pditr) {
// outBufferTmp.push_back(*pditr);
// ++count;
// }
// outBufferTmp[sizeIndex] = count;
// typename PolyLinePolygonData<true, Unit>::iteratorHoles pdHoleItr;
// for(pdHoleItr = (*itr).beginHoles(); pdHoleItr != (*itr).endHoles(); ++pdHoleItr) {
// outBufferTmp.push_back(0);
// unsigned int sizeIndex2 = outBufferTmp.size() - 1;
// int count2 = 0;
// for(pditr = (*pdHoleItr).begin(); pditr != (*pdHoleItr).end(); ++pditr) {
// outBufferTmp.push_back(*pditr);
// ++count2;
// }
// outBufferTmp[sizeIndex2] = -count;
// }
// ++itr;
// }
// }
// };
const int VERTICAL_HEAD = 1, HEAD_TO_TAIL = 2, TAIL_TO_TAIL = 4, SOLID_TO_RIGHT = 8;
//EVERY FUNCTION in this DEF file should be explicitly defined as inline
//microsoft compiler improperly warns whenever you cast an integer to bool
//call this function on an integer to convert it to bool without a warning
template <class T>
inline bool to_bool(const T& val) { return val != 0; }
//default constructor (for preallocation)
template <typename Unit>
inline PolyLine<Unit>::PolyLine() : ptdata_() ,headp_(0), tailp_(0), state_(-1) {}
//constructor
template <typename Unit>
inline PolyLine<Unit>::PolyLine(orientation_2d orient, Unit coord, Side side) :
ptdata_(1, coord),
headp_(0),
tailp_(0),
state_(orient.to_int() +
(side << 3)) {}
//copy constructor
template <typename Unit>
inline PolyLine<Unit>::PolyLine(const PolyLine<Unit>& pline) : ptdata_(pline.ptdata_),
headp_(pline.headp_),
tailp_(pline.tailp_),
state_(pline.state_) {}
//destructor
template <typename Unit>
inline PolyLine<Unit>::~PolyLine() {
//clear out data just in case it is read later
headp_ = tailp_ = 0;
state_ = 0;
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::operator=(const PolyLine<Unit>& that) {
if(!(this == &that)) {
headp_ = that.headp_;
tailp_ = that.tailp_;
ptdata_ = that.ptdata_;
state_ = that.state_;
}
return *this;
}
template <typename Unit>
inline bool PolyLine<Unit>::operator==(const PolyLine<Unit>& b) const {
return this == &b || (state_ == b.state_ &&
headp_ == b.headp_ &&
tailp_ == b.tailp_);
}
//valid PolyLine
template <typename Unit>
inline bool PolyLine<Unit>::isValid() const {
return state_ > -1; }
//first coordinate is an X value
//first segment is vertical
template <typename Unit>
inline bool PolyLine<Unit>::verticalHead() const {
return state_ & VERTICAL_HEAD;
}
//retrun true is PolyLine has odd number of coordiantes
template <typename Unit>
inline bool PolyLine<Unit>::oddLength() const {
return to_bool((ptdata_.size()-1) % 2);
}
//last coordiante is an X value
//last segment is vertical
template <typename Unit>
inline bool PolyLine<Unit>::verticalTail() const {
return to_bool(verticalHead() ^ oddLength());
}
template <typename Unit>
inline orientation_2d PolyLine<Unit>::tailOrient() const {
return (verticalTail() ? VERTICAL : HORIZONTAL);
}
template <typename Unit>
inline orientation_2d PolyLine<Unit>::headOrient() const {
return (verticalHead() ? VERTICAL : HORIZONTAL);
}
template <typename Unit>
inline End PolyLine<Unit>::endConnectivity(End end) const {
//Tail should be defined as true
if(end) { return tailToTail(); }
return headToTail();
}
template <typename Unit>
inline bool PolyLine<Unit>::headToTail() const {
return to_bool(state_ & HEAD_TO_TAIL);
}
template <typename Unit>
inline bool PolyLine<Unit>::headToHead() const {
return to_bool(!headToTail());
}
template <typename Unit>
inline bool PolyLine<Unit>::tailToHead() const {
return to_bool(!tailToTail());
}
template <typename Unit>
inline bool PolyLine<Unit>::tailToTail() const {
return to_bool(state_ & TAIL_TO_TAIL);
}
template <typename Unit>
inline Side PolyLine<Unit>::solidSide() const {
return solidToRight(); }
template <typename Unit>
inline bool PolyLine<Unit>::solidToRight() const {
return to_bool(state_ & SOLID_TO_RIGHT) != 0;
}
template <typename Unit>
inline bool PolyLine<Unit>::active() const {
return !to_bool(tailp_);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::pushCoordinate(Unit coord) {
ptdata_.push_back(coord);
return *this;
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::popCoordinate() {
ptdata_.pop_back();
return *this;
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::pushPoint(const point_data<Unit>& point) {
point_data<Unit> endPt = getEndPoint();
//vertical is true, horizontal is false
if((tailOrient().to_int() ? point.get(VERTICAL) == endPt.get(VERTICAL) : point.get(HORIZONTAL) == endPt.get(HORIZONTAL))) {
//we were pushing a colinear segment
return popCoordinate();
}
return pushCoordinate(tailOrient().to_int() ? point.get(VERTICAL) : point.get(HORIZONTAL));
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::extendTail(Unit delta) {
ptdata_.back() += delta;
return *this;
}
//private member function that creates a link from this PolyLine to that
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinTo_(End thisEnd, PolyLine<Unit>& that, End end) {
if(thisEnd){
tailp_ = &that;
state_ &= ~TAIL_TO_TAIL; //clear any previous state_ of bit (for safety)
state_ |= (end << 2); //place bit into mask
} else {
headp_ = &that;
state_ &= ~HEAD_TO_TAIL; //clear any previous state_ of bit (for safety)
state_ |= (end << 1); //place bit into mask
}
return *this;
}
//join two PolyLines (both ways of the association)
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinTo(End thisEnd, PolyLine<Unit>& that, End end) {
joinTo_(thisEnd, that, end);
that.joinTo_(end, *this, thisEnd);
return *this;
}
//convenience functions for joining PolyLines
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinToTail(PolyLine<Unit>& that, End end) {
return joinTo(TAIL, that, end);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinToHead(PolyLine<Unit>& that, End end) {
return joinTo(HEAD, that, end);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinHeadToHead(PolyLine<Unit>& that) {
return joinToHead(that, HEAD);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinHeadToTail(PolyLine<Unit>& that) {
return joinToHead(that, TAIL);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinTailToHead(PolyLine<Unit>& that) {
return joinToTail(that, HEAD);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::joinTailToTail(PolyLine<Unit>& that) {
return joinToTail(that, TAIL);
}
template <typename Unit>
inline PolyLine<Unit>& PolyLine<Unit>::disconnectTails() {
next(TAIL)->state_ &= !TAIL_TO_TAIL;
next(TAIL)->tailp_ = 0;
state_ &= !TAIL_TO_TAIL;
tailp_ = 0;
return *this;
}
template <typename Unit>
inline Unit PolyLine<Unit>::getEndCoord(End end) const {
if(end)
return ptdata_.back();
return ptdata_.front();
}
template <typename Unit>
inline orientation_2d PolyLine<Unit>::segmentOrient(unsigned int index) const {
return (to_bool((unsigned int)verticalHead() ^ (index % 2)) ? VERTICAL : HORIZONTAL);
}
template <typename Unit>
inline point_data<Unit> PolyLine<Unit>::getPoint(unsigned int index) const {
//assert(isValid() && headp_->isValid()) ("PolyLine: headp_ must be valid");
point_data<Unit> pt;
pt.set(HORIZONTAL, ptdata_[index]);
pt.set(VERTICAL, ptdata_[index]);
Unit prevCoord;
if(index == 0) {
prevCoord = headp_->getEndCoord(headToTail());
} else {
prevCoord = ptdata_[index-1];
}
pt.set(segmentOrient(index), prevCoord);
return pt;
}
template <typename Unit>
inline point_data<Unit> PolyLine<Unit>::getEndPoint(End end) const {
return getPoint((end ? numSegments() - 1 : (unsigned int)0));
}
template <typename Unit>
inline Unit PolyLine<Unit>::operator[] (unsigned int index) const {
//assert(ptdata_.size() > index) ("PolyLine: out of bounds index");
return ptdata_[index];
}
template <typename Unit>
inline unsigned int PolyLine<Unit>::numSegments() const {
return ptdata_.size();
}
template <typename Unit>
inline PolyLine<Unit>* PolyLine<Unit>::next(End end) const {
return (end ? tailp_ : headp_);
}
template <typename Unit>
inline ActiveTail<Unit>::ActiveTail() : tailp_(0), otherTailp_(0), holesList_() {}
template <typename Unit>
inline ActiveTail<Unit>::ActiveTail(orientation_2d orient, Unit coord, Side solidToRight, ActiveTail* otherTailp) :
tailp_(0), otherTailp_(0), holesList_() {
tailp_ = createPolyLine(orient, coord, solidToRight);
otherTailp_ = otherTailp;
}
template <typename Unit>
inline ActiveTail<Unit>::ActiveTail(PolyLine<Unit>* active, ActiveTail<Unit>* otherTailp) :
tailp_(active), otherTailp_(otherTailp), holesList_() {}
//copy constructor
template <typename Unit>
inline ActiveTail<Unit>::ActiveTail(const ActiveTail<Unit>& that) : tailp_(that.tailp_), otherTailp_(that.otherTailp_), holesList_() {}
//destructor
template <typename Unit>
inline ActiveTail<Unit>::~ActiveTail() {
//clear them in case the memory is read later
tailp_ = 0; otherTailp_ = 0;
}
template <typename Unit>
inline ActiveTail<Unit>& ActiveTail<Unit>::operator=(const ActiveTail<Unit>& that) {
//self assignment is safe in this case
tailp_ = that.tailp_;
otherTailp_ = that.otherTailp_;
return *this;
}
template <typename Unit>
inline bool ActiveTail<Unit>::operator==(const ActiveTail<Unit>& b) const {
return tailp_ == b.tailp_ && otherTailp_ == b.otherTailp_;
}
template <typename Unit>
inline bool ActiveTail<Unit>::operator<(const ActiveTail<Unit>& b) const {
return tailp_->getEndPoint().get(VERTICAL) < b.tailp_->getEndPoint().get(VERTICAL);
}
template <typename Unit>
inline bool ActiveTail<Unit>::operator<=(const ActiveTail<Unit>& b) const {
return !(*this > b); }
template <typename Unit>
inline bool ActiveTail<Unit>::operator>(const ActiveTail<Unit>& b) const {
return b < (*this); }
template <typename Unit>
inline bool ActiveTail<Unit>::operator>=(const ActiveTail<Unit>& b) const {
return !(*this < b); }
template <typename Unit>
inline PolyLine<Unit>* ActiveTail<Unit>::getTail() const {
return tailp_; }
template <typename Unit>
inline PolyLine<Unit>* ActiveTail<Unit>::getOtherTail() const {
return otherTailp_->tailp_; }
template <typename Unit>
inline ActiveTail<Unit>* ActiveTail<Unit>::getOtherActiveTail() const {
return otherTailp_; }
template <typename Unit>
inline bool ActiveTail<Unit>::isOtherTail(const ActiveTail<Unit>& b) {
// assert( (tailp_ == b.getOtherTail() && getOtherTail() == b.tailp_) ||
// (tailp_ != b.getOtherTail() && getOtherTail() != b.tailp_))
// ("ActiveTail: Active tails out of sync");
return otherTailp_ == &b;
}
template <typename Unit>
inline ActiveTail<Unit>& ActiveTail<Unit>::updateTail(PolyLine<Unit>* newTail) {
tailp_ = newTail;
return *this;
}
template <typename Unit>
inline ActiveTail<Unit>* ActiveTail<Unit>::addHole(ActiveTail<Unit>* hole, bool fractureHoles) {
if(!fractureHoles){
holesList_.push_back(hole);
copyHoles(*hole);
copyHoles(*(hole->getOtherActiveTail()));
return this;
}
ActiveTail<Unit>* h, *v;
ActiveTail<Unit>* other = hole->getOtherActiveTail();
if(other->getOrient() == VERTICAL) {
//assert that hole.getOrient() == HORIZONTAL
//this case should never happen
h = hole;
v = other;
} else {
//assert that hole.getOrient() == VERTICAL
h = other;
v = hole;
}
h->pushCoordinate(v->getCoordinate());
//assert that h->getOrient() == VERTICAL
//v->pushCoordinate(getCoordinate());
//assert that v->getOrient() == VERTICAL
//I can't close a figure by adding a hole, so pass zero for xMin and yMin
std::vector<Unit> tmpVec;
ActiveTail<Unit>::joinChains(this, h, false, tmpVec);
return v;
}
template <typename Unit>
inline const std::list<ActiveTail<Unit>*>& ActiveTail<Unit>::getHoles() const {
return holesList_;
}
template <typename Unit>
inline void ActiveTail<Unit>::copyHoles(ActiveTail<Unit>& that) {
holesList_.splice(holesList_.end(), that.holesList_); //splice the two lists together
}
template <typename Unit>
inline bool ActiveTail<Unit>::solidToRight() const {
return getTail()->solidToRight(); }
template <typename Unit>
inline Unit ActiveTail<Unit>::getCoord() const {
return getTail()->getEndCoord(); }
template <typename Unit>
inline Unit ActiveTail<Unit>::getCoordinate() const {
return getCoord(); }
template <typename Unit>
inline orientation_2d ActiveTail<Unit>::getOrient() const {
return getTail()->tailOrient(); }
template <typename Unit>
inline void ActiveTail<Unit>::pushCoordinate(Unit coord) {
//appropriately handle any co-linear polyline segments by calling push point internally
point_data<Unit> p;
p.set(HORIZONTAL, coord);
p.set(VERTICAL, coord);
//if we are vertical assign the last coordinate (an X) to p.x, else to p.y
p.set(getOrient().get_perpendicular(), getCoordinate());
tailp_->pushPoint(p);
}
//global utility functions
template <typename Unit>
inline PolyLine<Unit>* createPolyLine(orientation_2d orient, Unit coord, Side side) {
return new PolyLine<Unit>(orient, coord, side);
}
template <typename Unit>
inline void destroyPolyLine(PolyLine<Unit>* pLine) {
delete pLine;
}
template <typename Unit>
inline ActiveTail<Unit>* createActiveTail() {
//consider replacing system allocator with ActiveTail memory pool
return new ActiveTail<Unit>();
}
template <typename Unit>
inline void destroyActiveTail(ActiveTail<Unit>* aTail) {
delete aTail;
}
//no recursion, to prevent max recursion depth errors
template <typename Unit>
inline void ActiveTail<Unit>::destroyContents() {
tailp_->disconnectTails();
PolyLine<Unit>* nextPolyLinep = tailp_->next(HEAD);
End end = tailp_->endConnectivity(HEAD);
destroyPolyLine(tailp_);
while(nextPolyLinep) {
End nextEnd = nextPolyLinep->endConnectivity(!end); //get the direction of next polyLine
PolyLine<Unit>* nextNextPolyLinep = nextPolyLinep->next(!end); //get the next polyline
destroyPolyLine(nextPolyLinep); //destroy the current polyline
end = nextEnd;
nextPolyLinep = nextNextPolyLinep;
}
}
template <typename Unit>
inline typename ActiveTail<Unit>::iterator ActiveTail<Unit>::begin(bool isHole, orientation_2d orient) const {
return iterator(this, isHole, orient);
}
template <typename Unit>
inline typename ActiveTail<Unit>::iterator ActiveTail<Unit>::end() const {
return iterator();
}
template <typename Unit>
inline typename ActiveTail<Unit>::iteratorHoles ActiveTail<Unit>::beginHoles() const {
return holesList_.begin();
}
template <typename Unit>
inline typename ActiveTail<Unit>::iteratorHoles ActiveTail<Unit>::endHoles() const {
return holesList_.end();
}
template <typename Unit>
inline void ActiveTail<Unit>::writeOutFigureItrs(iterator& beginOut, iterator& endOut, bool isHole, orientation_2d orient) const {
beginOut = begin(isHole, orient);
endOut = end();
}
template <typename Unit>
inline void ActiveTail<Unit>::writeOutFigureHoleItrs(iteratorHoles& beginOut, iteratorHoles& endOut) const {
beginOut = beginHoles();
endOut = endHoles();
}
template <typename Unit>
inline void ActiveTail<Unit>::writeOutFigure(std::vector<Unit>& outVec, bool isHole) const {
//we start writing out the polyLine that this active tail points to at its tail
std::size_t size = outVec.size();
outVec.push_back(0); //place holder for size
PolyLine<Unit>* nextPolyLinep = 0;
if(!isHole){
nextPolyLinep = otherTailp_->tailp_->writeOut(outVec);
} else {
nextPolyLinep = tailp_->writeOut(outVec);
}
Unit firsty = outVec[size + 1];
if((getOrient() == HORIZONTAL) ^ !isHole) {
//our first coordinate is a y value, so we need to rotate it to the end
typename std::vector<Unit>::iterator tmpItr = outVec.begin();
tmpItr += size;
outVec.erase(++tmpItr); //erase the 2nd element
}
End startEnd = tailp_->endConnectivity(HEAD);
if(isHole) startEnd = otherTailp_->tailp_->endConnectivity(HEAD);
while(nextPolyLinep) {
bool nextStartEnd = nextPolyLinep->endConnectivity(!startEnd);
nextPolyLinep = nextPolyLinep->writeOut(outVec, startEnd);
startEnd = nextStartEnd;
}
if((getOrient() == HORIZONTAL) ^ !isHole) {
//we want to push the y value onto the end since we ought to have ended with an x
outVec.push_back(firsty); //should never be executed because we want first value to be an x
}
//the vector contains the coordinates of the linked list of PolyLines in the correct order
//first element is supposed to be the size
outVec[size] = outVec.size() - 1 - size; //number of coordinates in vector
//assert outVec[size] % 2 == 0 //it should be even
//make the size negative for holes
outVec[size] *= (isHole ? -1 : 1);
}
//no recursion to prevent max recursion depth errors
template <typename Unit>
inline PolyLine<Unit>* PolyLine<Unit>::writeOut(std::vector<Unit>& outVec, End startEnd) const {
if(startEnd == HEAD){
//forward order
outVec.insert(outVec.end(), ptdata_.begin(), ptdata_.end());
return tailp_;
}else{
//reverse order
//do not reserve because we expect outVec to be large enough already
for(int i = ptdata_.size() - 1; i >= 0; --i){
outVec.push_back(ptdata_[i]);
}
//NT didn't know about this version of the API....
//outVec.insert(outVec.end(), ptdata_.rbegin(), ptdata_.rend());
return headp_;
}
}
//solid indicates if it was joined by a solit or a space
template <typename Unit>
inline ActiveTail<Unit>* ActiveTail<Unit>::joinChains(ActiveTail<Unit>* at1, ActiveTail<Unit>* at2, bool solid, std::vector<Unit>& outBufferTmp)
{
//checks to see if we closed a figure
if(at1->isOtherTail(*at2)){
//value of solid tells us if we closed solid or hole
//and output the solid or handle the hole appropriately
//if the hole needs to fracture across horizontal partition boundary we need to notify
//the calling context to do so
if(solid) {
//the chains are being joined because there is solid to the right
//this means that if the figure is closed at this point it must be a hole
//because otherwise it would have to have another vertex to the right of this one
//and would not be closed at this point
return at1;
} else {
//assert pG != 0
//the figure that was closed is a shell
at1->writeOutFigure(outBufferTmp);
//process holes of the polygon
at1->copyHoles(*at2); //there should not be holes on at2, but if there are, copy them over
const std::list<ActiveTail<Unit>*>& holes = at1->getHoles();
for(typename std::list<ActiveTail<Unit>*>::const_iterator litr = holes.begin(); litr != holes.end(); ++litr) {
(*litr)->writeOutFigure(outBufferTmp, true);
//delete the hole
(*litr)->destroyContents();
destroyActiveTail((*litr)->getOtherActiveTail());
destroyActiveTail((*litr));
}
//delete the polygon
at1->destroyContents();
//at2 contents are the same as at1, so it should not destroy them
destroyActiveTail(at1);
destroyActiveTail(at2);
}
return 0;
}
//join the two partial polygons into one large partial polygon
at1->getTail()->joinTailToTail(*(at2->getTail()));
*(at1->getOtherActiveTail()) = ActiveTail(at1->getOtherTail(), at2->getOtherActiveTail());
*(at2->getOtherActiveTail()) = ActiveTail(at2->getOtherTail(), at1->getOtherActiveTail());
at1->getOtherActiveTail()->copyHoles(*at1);
at1->getOtherActiveTail()->copyHoles(*at2);
destroyActiveTail(at1);
destroyActiveTail(at2);
return 0;
}
//solid indicates if it was joined by a solit or a space
template <typename Unit>
template <typename PolygonT>
inline ActiveTail<Unit>* ActiveTail<Unit>::joinChains(ActiveTail<Unit>* at1, ActiveTail<Unit>* at2, bool solid,
std::vector<PolygonT>& outBufferTmp) {
//checks to see if we closed a figure
if(at1->isOtherTail(*at2)){
//value of solid tells us if we closed solid or hole
//and output the solid or handle the hole appropriately
//if the hole needs to fracture across horizontal partition boundary we need to notify
//the calling context to do so
if(solid) {
//the chains are being joined because there is solid to the right
//this means that if the figure is closed at this point it must be a hole
//because otherwise it would have to have another vertex to the right of this one
//and would not be closed at this point
return at1;
} else {
//assert pG != 0
//the figure that was closed is a shell
outBufferTmp.push_back(at1);
at1->copyHoles(*at2); //there should not be holes on at2, but if there are, copy them over
}
return 0;
}
//join the two partial polygons into one large partial polygon
at1->getTail()->joinTailToTail(*(at2->getTail()));
*(at1->getOtherActiveTail()) = ActiveTail<Unit>(at1->getOtherTail(), at2->getOtherActiveTail());
*(at2->getOtherActiveTail()) = ActiveTail<Unit>(at2->getOtherTail(), at1->getOtherActiveTail());
at1->getOtherActiveTail()->copyHoles(*at1);
at1->getOtherActiveTail()->copyHoles(*at2);
destroyActiveTail(at1);
destroyActiveTail(at2);
return 0;
}
template <class TKey, class T> inline typename std::map<TKey, T>::iterator findAtNext(std::map<TKey, T>& theMap,
typename std::map<TKey, T>::iterator pos, const TKey& key)
{
if(pos == theMap.end()) return theMap.find(key);
//if they match the mapItr is pointing to the correct position
if(pos->first < key) {
return theMap.find(key);
}
if(pos->first > key) {
return theMap.end();
}
//else they are equal and no need to do anything to the iterator
return pos;
}
// createActiveTailsAsPair is called in these two end cases of geometry
// 1. lower left concave corner
// ###|
// ###|
// ###|###
// ###|###
// 2. lower left convex corner
// |###
// |###
// |
// |
// In case 1 there may be a hole propigated up from the bottom. If the fracture option is enabled
// the two active tails that form the filament fracture line edges can become the new active tail pair
// by pushing x and y onto them. Otherwise the hole simply needs to be associated to one of the new active tails
// with add hole
template <typename Unit>
inline std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> createActiveTailsAsPair(Unit x, Unit y, bool solid, ActiveTail<Unit>* phole, bool fractureHoles) {
ActiveTail<Unit>* at1 = 0;
ActiveTail<Unit>* at2 = 0;
if(!phole || !fractureHoles){
at1 = createActiveTail<Unit>();
at2 = createActiveTail<Unit>();
(*at1) = ActiveTail<Unit>(VERTICAL, x, solid, at2);
(*at2) = ActiveTail<Unit>(HORIZONTAL, y, !solid, at1);
//provide a function through activeTail class to provide this
at1->getTail()->joinHeadToHead(*(at2->getTail()));
if(phole)
at1->addHole(phole, fractureHoles); //assert fractureHoles == false
return std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*>(at1, at2);
}
//assert phole is not null
//assert fractureHoles is true
if(phole->getOrient() == VERTICAL) {
at2 = phole;
} else {
at2 = phole->getOtherActiveTail(); //should never be executed since orientation is expected to be vertical
}
//assert solid == false, we should be creating a corner with solid below and to the left if there was a hole
at1 = at2->getOtherActiveTail();
//assert at1 is horizontal
at1->pushCoordinate(x);
//assert at2 is vertical
at2->pushCoordinate(y);
return std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*>(at1, at2);
}
//Process edges connects vertical input edges (right or left edges of figures) to horizontal edges stored as member
//data of the scanline object. It also creates now horizontal edges as needed to construct figures from edge data.
//
//There are only 12 geometric end cases where the scanline intersects a horizontal edge and even fewer unique
//actions to take:
// 1. Solid on both sides of the vertical partition after the current position and space on both sides before
// ###|###
// ###|###
// |
// |
// This case does not need to be handled because there is no vertical edge at the current x coordinate.
//
// 2. Solid on both sides of the vertical partition before the current position and space on both sides after
// |
// |
// ###|###
// ###|###
// This case does not need to be handled because there is no vertical edge at the current x coordinate.
//
// 3. Solid on the left of the vertical partition after the current position and space elsewhere
// ###|
// ###|
// |
// |
// The horizontal edge from the left is found and turns upward because of the vertical right edge to become
// the currently active vertical edge.
//
// 4. Solid on the left of the vertical partion before the current position and space elsewhere
// |
// |
// ###|
// ###|
// The horizontal edge from the left is found and joined to the currently active vertical edge.
//
// 5. Solid to the right above and below and solid to the left above current position.
// ###|###
// ###|###
// |###
// |###
// The horizontal edge from the left is found and joined to the currently active vertical edge,
// potentially closing a hole.
//
// 6. Solid on the left of the vertical partion before the current position and solid to the right above and below
// |###
// |###
// ###|###
// ###|###
// The horizontal edge from the left is found and turns upward because of the vertical right edge to become
// the currently active vertical edge.
//
// 7. Solid on the right of the vertical partition after the current position and space elsewhere
// |###
// |###
// |
// |
// Create two new ActiveTails, one is added to the horizontal edges and the other becomes the vertical currentTail
//
// 8. Solid on the right of the vertical partion before the current position and space elsewhere
// |
// |
// |###
// |###
// The currentTail vertical edge turns right and is added to the horizontal edges data
//
// 9. Solid to the right above and solid to the left above and below current position.
// ###|###
// ###|###
// ###|
// ###|
// The currentTail vertical edge turns right and is added to the horizontal edges data
//
// 10. Solid on the left of the vertical partion above and below the current position and solid to the right below
// ###|
// ###|
// ###|###
// ###|###
// Create two new ActiveTails, one is added to the horizontal edges data and the other becomes the vertical currentTail
//
// 11. Solid to the right above and solid to the left below current position.
// |###
// |###
// ###|
// ###|
// The currentTail vertical edge joins the horizontal edge from the left (may close a polygon)
// Create two new ActiveTails, one is added to the horizontal edges data and the other becomes the vertical currentTail
//
// 12. Solid on the left of the vertical partion above the current position and solid to the right below
// ###|
// ###|
// |###
// |###
// The currentTail vertical edge turns right and is added to the horizontal edges data.
// The horizontal edge from the left turns upward and becomes the currentTail vertical edge
//
template <bool orientT, typename Unit, typename polygon_concept_type>
inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::
processEdges(iterator& beginOutput, iterator& endOutput,
Unit currentX, std::vector<interval_data<Unit> >& leftEdges,
std::vector<interval_data<Unit> >& rightEdges) {
clearOutput_();
typename std::map<Unit, ActiveTail<Unit>*>::iterator nextMapItr = tailMap_.begin();
//foreach edge
unsigned int leftIndex = 0;
unsigned int rightIndex = 0;
bool bottomAlreadyProcessed = false;
ActiveTail<Unit>* currentTail = 0;
const Unit UnitMax = (std::numeric_limits<Unit>::max)();
while(leftIndex < leftEdges.size() || rightIndex < rightEdges.size()) {
interval_data<Unit> edges[2] = {interval_data<Unit> (UnitMax, UnitMax), interval_data<Unit> (UnitMax, UnitMax)};
bool haveNextEdge = true;
if(leftIndex < leftEdges.size())
edges[0] = leftEdges[leftIndex];
else
haveNextEdge = false;
if(rightIndex < rightEdges.size())
edges[1] = rightEdges[rightIndex];
else
haveNextEdge = false;
bool trailingEdge = edges[1].get(LOW) < edges[0].get(LOW);
interval_data<Unit> & edge = edges[trailingEdge];
interval_data<Unit> & nextEdge = edges[!trailingEdge];
//process this edge
if(!bottomAlreadyProcessed) {
//assert currentTail = 0
//process the bottom end of this edge
typename std::map<Unit, ActiveTail<Unit>*>::iterator thisMapItr = findAtNext(tailMap_, nextMapItr, edge.get(LOW));
if(thisMapItr != tailMap_.end()) {
//there is an edge in the map at the low end of this edge
//it needs to turn upward and become the current tail
ActiveTail<Unit>* tail = thisMapItr->second;
if(currentTail) {
//stitch currentTail into this tail
currentTail = tail->addHole(currentTail, fractureHoles_);
if(!fractureHoles_)
currentTail->pushCoordinate(currentX);
} else {
currentTail = tail;
currentTail->pushCoordinate(currentX);
}
//assert currentTail->getOrient() == VERTICAL
nextMapItr = thisMapItr; //set nextMapItr to the next position after this one
++nextMapItr;
//remove thisMapItr from the map
tailMap_.erase(thisMapItr);
} else {
//there is no edge in the map at the low end of this edge
//we need to create one and another one to be the current vertical tail
//if this is a trailing edge then there is space to the right of the vertical edge
//so pass the inverse of trailingEdge to indicate solid to the right
std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair =
createActiveTailsAsPair(currentX, edge.get(LOW), !trailingEdge, currentTail, fractureHoles_);
currentTail = tailPair.first;
tailMap_.insert(nextMapItr, std::pair<Unit, ActiveTail<Unit>*>(edge.get(LOW), tailPair.second));
// leave nextMapItr unchanged
}
}
if(haveNextEdge && edge.get(HIGH) == nextEdge.get(LOW)) {
//the top of this edge is equal to the bottom of the next edge, process them both
bottomAlreadyProcessed = true;
typename std::map<Unit, ActiveTail<Unit>*>::iterator thisMapItr = findAtNext(tailMap_, nextMapItr, edge.get(HIGH));
if(thisMapItr == tailMap_.end()) //assert this should never happen
return;
if(trailingEdge) {
//geometry at this position
// |##
// |##
// -----
// ##|
// ##|
//current tail should join thisMapItr tail
ActiveTail<Unit>* tail = thisMapItr->second;
//pass false because they are being joined because space is to the right and it will close a solid figure
ActiveTail<Unit>::joinChains(currentTail, tail, false, outputPolygons_);
//two new tails are created, the vertical becomes current tail, the horizontal becomes thisMapItr tail
//pass true becuase they are created at the lower left corner of some solid
//pass null because there is no hole pointer possible
std::pair<ActiveTail<Unit>*, ActiveTail<Unit>*> tailPair =
createActiveTailsAsPair<Unit>(currentX, edge.get(HIGH), true, 0, fractureHoles_);
currentTail = tailPair.first;
thisMapItr->second = tailPair.second;
} else {
//geometry at this position
// ##|
// ##|
// -----
// |##
// |##
//current tail should turn right
currentTail->pushCoordinate(edge.get(HIGH));
//thisMapItr tail should turn up
thisMapItr->second->pushCoordinate(currentX);
//thisMapItr tail becomes current tail and current tail becomes thisMapItr tail
std::swap(currentTail, thisMapItr->second);
}
nextMapItr = thisMapItr; //set nextMapItr to the next position after this one
++nextMapItr;
} else {
//there is a gap between the top of this edge and the bottom of the next, process the top of this edge
bottomAlreadyProcessed = false;
//process the top of this edge
typename std::map<Unit, ActiveTail<Unit>*>::iterator thisMapItr = findAtNext(tailMap_, nextMapItr, edge.get(HIGH));
if(thisMapItr != tailMap_.end()) {
//thisMapItr is pointing to a horizontal edge in the map at the top of this vertical edge
//we need to join them and potentially close a figure
//assert currentTail != 0
ActiveTail<Unit>* tail = thisMapItr->second;
//pass the opositve of trailing edge to mean that they are joined because of solid to the right
currentTail = ActiveTail<Unit>::joinChains(currentTail, tail, !trailingEdge, outputPolygons_);
nextMapItr = thisMapItr; //set nextMapItr to the next position after this one
++nextMapItr;
if(currentTail) {
Unit nextItrY = UnitMax;
if(nextMapItr != tailMap_.end()) {
nextItrY = nextMapItr->first;
}
//for it to be a hole this must have been a left edge
Unit leftY = UnitMax;
if(leftIndex + 1 < leftEdges.size())
leftY = leftEdges[leftIndex+1].get(LOW);
Unit rightY = nextEdge.get(LOW);
if(!haveNextEdge || (nextItrY < leftY && nextItrY < rightY)) {
//we need to add it to the next edge above it in the map
tail = nextMapItr->second;
tail = tail->addHole(currentTail, fractureHoles_);
if(fractureHoles_) {
//some small additional work stitching in the filament
tail->pushCoordinate(nextItrY);
nextMapItr->second = tail;
}
//set current tail to null
currentTail = 0;
}
}
//delete thisMapItr from the map
tailMap_.erase(thisMapItr);
} else {
//currentTail must turn right and be added into the map
currentTail->pushCoordinate(edge.get(HIGH));
//assert currentTail->getOrient() == HORIZONTAL
tailMap_.insert(nextMapItr, std::pair<Unit, ActiveTail<Unit>*>(edge.get(HIGH), currentTail));
//set currentTail to null
currentTail = 0;
//leave nextMapItr unchanged, it is still next
}
}
//increment index
leftIndex += !trailingEdge;
rightIndex += trailingEdge;
} //end while
beginOutput = outputPolygons_.begin();
endOutput = outputPolygons_.end();
} //end function
template<bool orientT, typename Unit, typename polygon_concept_type>
inline void ScanLineToPolygonItrs<orientT, Unit, polygon_concept_type>::clearOutput_() {
for(std::size_t i = 0; i < outputPolygons_.size(); ++i) {
ActiveTail<Unit>* at1 = outputPolygons_[i].yield();
const std::list<ActiveTail<Unit>*>& holes = at1->getHoles();
for(typename std::list<ActiveTail<Unit>*>::const_iterator litr = holes.begin(); litr != holes.end(); ++litr) {
//delete the hole
(*litr)->destroyContents();
destroyActiveTail((*litr)->getOtherActiveTail());
destroyActiveTail((*litr));
}
//delete the polygon
at1->destroyContents();
//at2 contents are the same as at1, so it should not destroy them
destroyActiveTail((at1)->getOtherActiveTail());
destroyActiveTail(at1);
}
outputPolygons_.clear();
}
} //polygon_formation namespace
template <bool orientT, typename Unit>
struct geometry_concept<polygon_formation::PolyLinePolygonWithHolesData<orientT, Unit> > {
typedef polygon_90_with_holes_concept type;
};
template <bool orientT, typename Unit>
struct geometry_concept<polygon_formation::PolyLineHoleData<orientT, Unit> > {
typedef polygon_90_concept type;
};
//public API to access polygon formation algorithm
template <typename output_container, typename iterator_type, typename concept_type>
unsigned int get_polygons(output_container& container, iterator_type begin, iterator_type end,
orientation_2d orient, bool fracture_holes, concept_type ) {
typedef typename output_container::value_type polygon_type;
typedef typename std::iterator_traits<iterator_type>::value_type::first_type coordinate_type;
polygon_type poly;
unsigned int countPolygons = 0;
typedef typename geometry_concept<polygon_type>::type polygon_concept_type;
polygon_formation::ScanLineToPolygonItrs<true, coordinate_type, polygon_concept_type> scanlineToPolygonItrsV(fracture_holes);
polygon_formation::ScanLineToPolygonItrs<false, coordinate_type, polygon_concept_type> scanlineToPolygonItrsH(fracture_holes);
std::vector<interval_data<coordinate_type> > leftEdges;
std::vector<interval_data<coordinate_type> > rightEdges;
coordinate_type prevPos = (std::numeric_limits<coordinate_type>::max)();
coordinate_type prevY = (std::numeric_limits<coordinate_type>::max)();
int count = 0;
for(iterator_type itr = begin;
itr != end; ++ itr) {
coordinate_type pos = (*itr).first;
if(pos != prevPos) {
if(orient == VERTICAL) {
typename polygon_formation::ScanLineToPolygonItrs<true, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
scanlineToPolygonItrsV.processEdges(itrPoly, itrPolyEnd, prevPos, leftEdges, rightEdges);
for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
++countPolygons;
assign(poly, *itrPoly);
container.insert(container.end(), poly);
}
} else {
typename polygon_formation::ScanLineToPolygonItrs<false, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
scanlineToPolygonItrsH.processEdges(itrPoly, itrPolyEnd, prevPos, leftEdges, rightEdges);
for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
++countPolygons;
assign(poly, *itrPoly);
container.insert(container.end(), poly);
}
}
leftEdges.clear();
rightEdges.clear();
prevPos = pos;
prevY = (*itr).second.first;
count = (*itr).second.second;
continue;
}
coordinate_type y = (*itr).second.first;
if(count != 0 && y != prevY) {
std::pair<interval_data<coordinate_type>, int> element(interval_data<coordinate_type>(prevY, y), count);
if(element.second == 1) {
if(leftEdges.size() && leftEdges.back().high() == element.first.low()) {
encompass(leftEdges.back(), element.first);
} else {
leftEdges.push_back(element.first);
}
} else {
if(rightEdges.size() && rightEdges.back().high() == element.first.low()) {
encompass(rightEdges.back(), element.first);
} else {
rightEdges.push_back(element.first);
}
}
}
prevY = y;
count += (*itr).second.second;
}
if(orient == VERTICAL) {
typename polygon_formation::ScanLineToPolygonItrs<true, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
scanlineToPolygonItrsV.processEdges(itrPoly, itrPolyEnd, prevPos, leftEdges, rightEdges);
for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
++countPolygons;
assign(poly, *itrPoly);
container.insert(container.end(), poly);
}
} else {
typename polygon_formation::ScanLineToPolygonItrs<false, coordinate_type, polygon_concept_type>::iterator itrPoly, itrPolyEnd;
scanlineToPolygonItrsH.processEdges(itrPoly, itrPolyEnd, prevPos, leftEdges, rightEdges);
for( ; itrPoly != itrPolyEnd; ++ itrPoly) {
++countPolygons;
assign(poly, *itrPoly);
container.insert(container.end(), poly);
}
}
return countPolygons;
}
}
}
#endif