ocr_clipper.hpp

/*******************************************************************************
*                                                                              *
* Author    :  Angus Johnson                                                   *
* Version   :  6.4.2                                                           *
* Date      :  27 February 2017                                                *
* Website   :  http://www.angusj.com                                           *
* Copyright :  Angus Johnson 2010-2017                                         *
*                                                                              *
* License:                                                                     *
* Use, modification & distribution is subject to Boost Software License Ver 1. *
* http://www.boost.org/LICENSE_1_0.txt                                         *
*                                                                              *
* Attributions:                                                                *
* The code in this library is an extension of Bala Vatti's clipping algorithm: *
* "A generic solution to polygon clipping"                                     *
* Communications of the ACM, Vol 35, Issue 7 (July 1992) pp 56-63.             *
* http://portal.acm.org/citation.cfm?id=129906                                 *
*                                                                              *
* Computer graphics and geometric modeling: implementation and algorithms      *
* By Max K. Agoston                                                            *
* Springer; 1 edition (January 4, 2005)                                        *
* http://books.google.com/books?q=vatti+clipping+agoston                       *
*                                                                              *
* See also:                                                                    *
* "Polygon Offsetting by Computing Winding Numbers"                            *
* Paper no. DETC2005-85513 pp. 565-575                                         *
* ASME 2005 International Design Engineering Technical Conferences             *
* and Computers and Information in Engineering Conference (IDETC/CIE2005)      *
* September 24-28, 2005 , Long Beach, California, USA                          *
* http://www.me.berkeley.edu/~mcmains/pubs/DAC05OffsetPolygon.pdf              *
*                                                                              *
*******************************************************************************/

#ifndef clipper_hpp
#define clipper_hpp

#define CLIPPER_VERSION "6.4.2"

//use_int32: When enabled 32bit ints are used instead of 64bit ints. This
//improve performance but coordinate values are limited to the range +/- 46340
//#define use_int32

//use_xyz: adds a Z member to IntPoint. Adds a minor cost to perfomance.
//#define use_xyz

//use_lines: Enables line clipping. Adds a very minor cost to performance.
#define use_lines

//use_deprecated: Enables temporary support for the obsolete functions
//#define use_deprecated  

#include <vector>
#include <list>
#include <set>
#include <stdexcept>
#include <cstring>
#include <cstdlib>
#include <ostream>
#include <functional>
#include <queue>

namespace ClipperLib {

enum ClipType {
    ctIntersection, ctUnion, ctDifference, ctXor
};
enum PolyType {
    ptSubject, ptClip
};
//By far the most widely used winding rules for polygon filling are
//EvenOdd & NonZero (GDI, GDI+, XLib, OpenGL, Cairo, AGG, Quartz, SVG, Gr32)
//Others rules include Positive, Negative and ABS_GTR_EQ_TWO (only in OpenGL)
//see http://glprogramming.com/red/chapter11.html
enum PolyFillType {
    pftEvenOdd, pftNonZero, pftPositive, pftNegative
};

#ifdef use_int32
typedef int cInt;
static cInt const loRange = 0x7FFF;
static cInt const hiRange = 0x7FFF;
#else
typedef signed long long cInt;
static cInt const loRange = 0x3FFFFFFF;
static cInt const hiRange = 0x3FFFFFFFFFFFFFFFLL;
typedef signed long long long64;     //used by Int128 class
typedef unsigned long long ulong64;

#endif

struct IntPoint {
    cInt X;
    cInt Y;
#ifdef use_xyz
    cInt Z;
    IntPoint(cInt x = 0, cInt y = 0, cInt z = 0): X(x), Y(y), Z(z) {};
#else

    IntPoint(cInt x = 0, cInt y = 0) : X(x), Y(y) {};
#endif

    friend inline bool operator==(const IntPoint &a, const IntPoint &b) {
        return a.X == b.X && a.Y == b.Y;
    }

    friend inline bool operator!=(const IntPoint &a, const IntPoint &b) {
        return a.X != b.X || a.Y != b.Y;
    }
};
//------------------------------------------------------------------------------

typedef std::vector <IntPoint> Path;
typedef std::vector <Path> Paths;

inline Path &operator<<(Path &poly, const IntPoint &p) {
    poly.push_back(p);
    return poly;
}

inline Paths &operator<<(Paths &polys, const Path &p) {
    polys.push_back(p);
    return polys;
}

std::ostream &operator<<(std::ostream &s, const IntPoint &p);

std::ostream &operator<<(std::ostream &s, const Path &p);

std::ostream &operator<<(std::ostream &s, const Paths &p);

struct DoublePoint {
    double X;
    double Y;

    DoublePoint(double x = 0, double y = 0) : X(x), Y(y) {}

    DoublePoint(IntPoint ip) : X((double) ip.X), Y((double) ip.Y) {}
};
//------------------------------------------------------------------------------

#ifdef use_xyz
typedef void (*ZFillCallback)(IntPoint& e1bot, IntPoint& e1top, IntPoint& e2bot, IntPoint& e2top, IntPoint& pt);
#endif

enum InitOptions {
    ioReverseSolution = 1, ioStrictlySimple = 2, ioPreserveCollinear = 4
};
enum JoinType {
    jtSquare, jtRound, jtMiter
};
enum EndType {
    etClosedPolygon, etClosedLine, etOpenButt, etOpenSquare, etOpenRound
};

class PolyNode;

typedef std::vector<PolyNode *> PolyNodes;

class PolyNode {
public:
    PolyNode();

    virtual ~PolyNode() {};
    Path Contour;
    PolyNodes Childs;
    PolyNode *Parent;

    PolyNode *GetNext() const;

    bool IsHole() const;

    bool IsOpen() const;

    int ChildCount() const;

private:
    //PolyNode& operator =(PolyNode& other); 
    unsigned Index; //node index in Parent.Childs
    bool m_IsOpen;
    JoinType m_jointype;
    EndType m_endtype;

    PolyNode *GetNextSiblingUp() const;

    void AddChild(PolyNode &child);

    friend class Clipper; //to access Index
    friend class ClipperOffset;
};

class PolyTree : public PolyNode {
public:
    ~PolyTree() { Clear(); };

    PolyNode *GetFirst() const;

    void Clear();

    int Total() const;

private:
    //PolyTree& operator =(PolyTree& other);
    PolyNodes AllNodes;

    friend class Clipper; //to access AllNodes
};

bool Orientation(const Path &poly);

double Area(const Path &poly);

int PointInPolygon(const IntPoint &pt, const Path &path);

void SimplifyPolygon(const Path &in_poly, Paths &out_polys, PolyFillType fillType = pftEvenOdd);

void SimplifyPolygons(const Paths &in_polys, Paths &out_polys, PolyFillType fillType = pftEvenOdd);

void SimplifyPolygons(Paths &polys, PolyFillType fillType = pftEvenOdd);

void CleanPolygon(const Path &in_poly, Path &out_poly, double distance = 1.415);

void CleanPolygon(Path &poly, double distance = 1.415);

void CleanPolygons(const Paths &in_polys, Paths &out_polys, double distance = 1.415);

void CleanPolygons(Paths &polys, double distance = 1.415);

void MinkowskiSum(const Path &pattern, const Path &path, Paths &solution, bool pathIsClosed);

void MinkowskiSum(const Path &pattern, const Paths &paths, Paths &solution, bool pathIsClosed);

void MinkowskiDiff(const Path &poly1, const Path &poly2, Paths &solution);

void PolyTreeToPaths(const PolyTree &polytree, Paths &paths);

void ClosedPathsFromPolyTree(const PolyTree &polytree, Paths &paths);

void OpenPathsFromPolyTree(PolyTree &polytree, Paths &paths);

void ReversePath(Path &p);

void ReversePaths(Paths &p);

struct IntRect {
    cInt left;
    cInt top;
    cInt right;
    cInt bottom;
};

//enums that are used internally ...
enum EdgeSide {
    esLeft = 1, esRight = 2
};

//forward declarations (for stuff used internally) ...
struct TEdge;
struct IntersectNode;
struct LocalMinimum;
struct OutPt;
struct OutRec;
struct Join;

typedef std::vector<OutRec *> PolyOutList;
typedef std::vector<TEdge *> EdgeList;
typedef std::vector<Join *> JoinList;
typedef std::vector<IntersectNode *> IntersectList;

//------------------------------------------------------------------------------

//ClipperBase is the ancestor to the Clipper class. It should not be
//instantiated directly. This class simply abstracts the conversion of sets of
//polygon coordinates into edge objects that are stored in a LocalMinima list.
class ClipperBase {
public:
    ClipperBase();

    virtual ~ClipperBase();

    virtual bool AddPath(const Path &pg, PolyType PolyTyp, bool Closed);

    bool AddPaths(const Paths &ppg, PolyType PolyTyp, bool Closed);

    virtual void Clear();

    IntRect GetBounds();

    bool PreserveCollinear() { return m_PreserveCollinear; };

    void PreserveCollinear(bool value) { m_PreserveCollinear = value; };
protected:
    void DisposeLocalMinimaList();

    TEdge *AddBoundsToLML(TEdge *e, bool IsClosed);

    virtual void Reset();

    TEdge *ProcessBound(TEdge *E, bool IsClockwise);

    void InsertScanbeam(const cInt Y);

    bool PopScanbeam(cInt &Y);

    bool LocalMinimaPending();

    bool PopLocalMinima(cInt Y, const LocalMinimum *&locMin);

    OutRec *CreateOutRec();

    void DisposeAllOutRecs();

    void DisposeOutRec(PolyOutList::size_type index);

    void SwapPositionsInAEL(TEdge *edge1, TEdge *edge2);

    void DeleteFromAEL(TEdge *e);

    void UpdateEdgeIntoAEL(TEdge *&e);

    typedef std::vector <LocalMinimum> MinimaList;
    MinimaList::iterator m_CurrentLM;
    MinimaList m_MinimaList;

    bool m_UseFullRange;
    EdgeList m_edges;
    bool m_PreserveCollinear;
    bool m_HasOpenPaths;
    PolyOutList m_PolyOuts;
    TEdge *m_ActiveEdges;

    typedef std::priority_queue <cInt> ScanbeamList;
    ScanbeamList m_Scanbeam;
};
//------------------------------------------------------------------------------

class Clipper : public virtual ClipperBase {
public:
    Clipper(int initOptions = 0);

    bool Execute(ClipType clipType,
                 Paths &solution,
                 PolyFillType fillType = pftEvenOdd);

    bool Execute(ClipType clipType,
                 Paths &solution,
                 PolyFillType subjFillType,
                 PolyFillType clipFillType);

    bool Execute(ClipType clipType,
                 PolyTree &polytree,
                 PolyFillType fillType = pftEvenOdd);

    bool Execute(ClipType clipType,
                 PolyTree &polytree,
                 PolyFillType subjFillType,
                 PolyFillType clipFillType);

    bool ReverseSolution() { return m_ReverseOutput; };

    void ReverseSolution(bool value) { m_ReverseOutput = value; };

    bool StrictlySimple() { return m_StrictSimple; };

    void StrictlySimple(bool value) { m_StrictSimple = value; };
    //set the callback function for z value filling on intersections (otherwise Z is 0)
#ifdef use_xyz
    void ZFillFunction(ZFillCallback zFillFunc);
#endif
protected:
    virtual bool ExecuteInternal();

private:
    JoinList m_Joins;
    JoinList m_GhostJoins;
    IntersectList m_IntersectList;
    ClipType m_ClipType;
    typedef std::list <cInt> MaximaList;
    MaximaList m_Maxima;
    TEdge *m_SortedEdges;
    bool m_ExecuteLocked;
    PolyFillType m_ClipFillType;
    PolyFillType m_SubjFillType;
    bool m_ReverseOutput;
    bool m_UsingPolyTree;
    bool m_StrictSimple;
#ifdef use_xyz
    ZFillCallback   m_ZFill; //custom callback
#endif

    void SetWindingCount(TEdge &edge);

    bool IsEvenOddFillType(const TEdge &edge) const;

    bool IsEvenOddAltFillType(const TEdge &edge) const;

    void InsertLocalMinimaIntoAEL(const cInt botY);

    void InsertEdgeIntoAEL(TEdge *edge, TEdge *startEdge);

    void AddEdgeToSEL(TEdge *edge);

    bool PopEdgeFromSEL(TEdge *&edge);

    void CopyAELToSEL();

    void DeleteFromSEL(TEdge *e);

    void SwapPositionsInSEL(TEdge *edge1, TEdge *edge2);

    bool IsContributing(const TEdge &edge) const;

    bool IsTopHorz(const cInt XPos);

    void DoMaxima(TEdge *e);

    void ProcessHorizontals();

    void ProcessHorizontal(TEdge *horzEdge);

    void AddLocalMaxPoly(TEdge *e1, TEdge *e2, const IntPoint &pt);

    OutPt *AddLocalMinPoly(TEdge *e1, TEdge *e2, const IntPoint &pt);

    OutRec *GetOutRec(int idx);

    void AppendPolygon(TEdge *e1, TEdge *e2);

    void IntersectEdges(TEdge *e1, TEdge *e2, IntPoint &pt);

    OutPt *AddOutPt(TEdge *e, const IntPoint &pt);

    OutPt *GetLastOutPt(TEdge *e);

    bool ProcessIntersections(const cInt topY);

    void BuildIntersectList(const cInt topY);

    void ProcessIntersectList();

    void ProcessEdgesAtTopOfScanbeam(const cInt topY);

    void BuildResult(Paths &polys);

    void BuildResult2(PolyTree &polytree);

    void SetHoleState(TEdge *e, OutRec *outrec);

    void DisposeIntersectNodes();

    bool FixupIntersectionOrder();

    void FixupOutPolygon(OutRec &outrec);

    void FixupOutPolyline(OutRec &outrec);

    bool IsHole(TEdge *e);

    bool FindOwnerFromSplitRecs(OutRec &outRec, OutRec *&currOrfl);

    void FixHoleLinkage(OutRec &outrec);

    void AddJoin(OutPt *op1, OutPt *op2, const IntPoint offPt);

    void ClearJoins();

    void ClearGhostJoins();

    void AddGhostJoin(OutPt *op, const IntPoint offPt);

    bool JoinPoints(Join *j, OutRec *outRec1, OutRec *outRec2);

    void JoinCommonEdges();

    void DoSimplePolygons();

    void FixupFirstLefts1(OutRec *OldOutRec, OutRec *NewOutRec);

    void FixupFirstLefts2(OutRec *InnerOutRec, OutRec *OuterOutRec);

    void FixupFirstLefts3(OutRec *OldOutRec, OutRec *NewOutRec);

#ifdef use_xyz
    void SetZ(IntPoint& pt, TEdge& e1, TEdge& e2);
#endif
};
//------------------------------------------------------------------------------

class ClipperOffset {
public:
    ClipperOffset(double miterLimit = 2.0, double roundPrecision = 0.25);

    ~ClipperOffset();

    void AddPath(const Path &path, JoinType joinType, EndType endType);

    void AddPaths(const Paths &paths, JoinType joinType, EndType endType);

    void Execute(Paths &solution, double delta);

    void Execute(PolyTree &solution, double delta);

    void Clear();

    double MiterLimit;
    double ArcTolerance;
private:
    Paths m_destPolys;
    Path m_srcPoly;
    Path m_destPoly;
    std::vector <DoublePoint> m_normals;
    double m_delta, m_sinA, m_sin, m_cos;
    double m_miterLim, m_StepsPerRad;
    IntPoint m_lowest;
    PolyNode m_polyNodes;

    void FixOrientations();

    void DoOffset(double delta);

    void OffsetPoint(int j, int &k, JoinType jointype);

    void DoSquare(int j, int k);

    void DoMiter(int j, int k, double r);

    void DoRound(int j, int k);
};
//------------------------------------------------------------------------------

class clipperException : public std::exception {
public:
    clipperException(const char *description) : m_descr(description) {}

    virtual ~clipperException() throw() {}

    virtual const char *what() const throw() { return m_descr.c_str(); }

private:
    std::string m_descr;
};
//------------------------------------------------------------------------------

} //ClipperLib namespace

#endif //clipper_hpp