clipper.h

/*******************************************************************************
 *                                                                              *
 * 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              *
 *                                                                              *
 *******************************************************************************/

#pragma once

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

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;
};
//------------------------------------------------------------------------------

} // namespace ClipperLib

#endif // clipper_hpp