KBot/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