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diff --git a/polygon/clipper.cpp b/polygon/clipper.cpp new file mode 100644 index 0000000..6d6ce6e --- /dev/null +++ b/polygon/clipper.cpp @@ -0,0 +1,4642 @@ +/******************************************************************************* +* * +* Author : Angus Johnson * +* Version : 6.4.0 * +* Date : 2 July 2015 * +* Website : http://www.angusj.com * +* Copyright : Angus Johnson 2010-2015 * +* * +* 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 * +* * +*******************************************************************************/ + +/******************************************************************************* +* * +* This is a translation of the Delphi Clipper library and the naming style * +* used has retained a Delphi flavour. * +* * +*******************************************************************************/ + +#include "clipper.hpp" +#include <cmath> +#include <vector> +#include <algorithm> +#include <stdexcept> +#include <cstring> +#include <cstdlib> +#include <ostream> +#include <functional> + +namespace ClipperLib { + +static double const pi = 3.141592653589793238; +static double const two_pi = pi *2; +static double const def_arc_tolerance = 0.25; + +enum Direction { dRightToLeft, dLeftToRight }; + +static int const Unassigned = -1; //edge not currently 'owning' a solution +static int const Skip = -2; //edge that would otherwise close a path + +#define HORIZONTAL (-1.0E+40) +#define TOLERANCE (1.0e-20) +#define NEAR_ZERO(val) (((val) > -TOLERANCE) && ((val) < TOLERANCE)) + +struct TEdge { + IntPoint Bot; + IntPoint Curr; //current (updated for every new scanbeam) + IntPoint Top; + double Dx; + PolyType PolyTyp; + EdgeSide Side; //side only refers to current side of solution poly + int WindDelta; //1 or -1 depending on winding direction + int WindCnt; + int WindCnt2; //winding count of the opposite polytype + int OutIdx; + TEdge *Next; + TEdge *Prev; + TEdge *NextInLML; + TEdge *NextInAEL; + TEdge *PrevInAEL; + TEdge *NextInSEL; + TEdge *PrevInSEL; +}; + +struct IntersectNode { + TEdge *Edge1; + TEdge *Edge2; + IntPoint Pt; +}; + +struct LocalMinimum { + cInt Y; + TEdge *LeftBound; + TEdge *RightBound; +}; + +struct OutPt; + +//OutRec: contains a path in the clipping solution. Edges in the AEL will +//carry a pointer to an OutRec when they are part of the clipping solution. +struct OutRec { + int Idx; + bool IsHole; + bool IsOpen; + OutRec *FirstLeft; //see comments in clipper.pas + PolyNode *PolyNd; + OutPt *Pts; + OutPt *BottomPt; +}; + +struct OutPt { + int Idx; + IntPoint Pt; + OutPt *Next; + OutPt *Prev; +}; + +struct Join { + OutPt *OutPt1; + OutPt *OutPt2; + IntPoint OffPt; +}; + +struct LocMinSorter +{ + inline bool operator()(const LocalMinimum& locMin1, const LocalMinimum& locMin2) + { + return locMin2.Y < locMin1.Y; + } +}; + +//------------------------------------------------------------------------------ +//------------------------------------------------------------------------------ + +inline cInt Round(double val) +{ + if ((val < 0)) return static_cast<cInt>(val - 0.5); + else return static_cast<cInt>(val + 0.5); +} +//------------------------------------------------------------------------------ + +inline cInt Abs(cInt val) +{ + return val < 0 ? -val : val; +} + +//------------------------------------------------------------------------------ +// PolyTree methods ... +//------------------------------------------------------------------------------ + +void PolyTree::Clear() +{ + for (PolyNodes::size_type i = 0; i < AllNodes.size(); ++i) + delete AllNodes[i]; + AllNodes.resize(0); + Childs.resize(0); +} +//------------------------------------------------------------------------------ + +PolyNode* PolyTree::GetFirst() const +{ + if (!Childs.empty()) + return Childs[0]; + else + return 0; +} +//------------------------------------------------------------------------------ + +int PolyTree::Total() const +{ + int result = (int)AllNodes.size(); + //with negative offsets, ignore the hidden outer polygon ... + if (result > 0 && Childs[0] != AllNodes[0]) result--; + return result; +} + +//------------------------------------------------------------------------------ +// PolyNode methods ... +//------------------------------------------------------------------------------ + +PolyNode::PolyNode(): Childs(), Parent(0), Index(0), m_IsOpen(false) +{ + // Avoid uninitialized vars + m_endtype = etClosedPolygon; + m_jointype = jtSquare; +} +//------------------------------------------------------------------------------ + +int PolyNode::ChildCount() const +{ + return (int)Childs.size(); +} +//------------------------------------------------------------------------------ + +void PolyNode::AddChild(PolyNode& child) +{ + unsigned cnt = (unsigned)Childs.size(); + Childs.push_back(&child); + child.Parent = this; + child.Index = cnt; +} +//------------------------------------------------------------------------------ + +PolyNode* PolyNode::GetNext() const +{ + if (!Childs.empty()) + return Childs[0]; + else + return GetNextSiblingUp(); +} +//------------------------------------------------------------------------------ + +PolyNode* PolyNode::GetNextSiblingUp() const +{ + if (!Parent) //protects against PolyTree.GetNextSiblingUp() + return 0; + else if (Index == Parent->Childs.size() - 1) + return Parent->GetNextSiblingUp(); + else + return Parent->Childs[Index + 1]; +} +//------------------------------------------------------------------------------ + +bool PolyNode::IsHole() const +{ + bool result = true; + PolyNode* node = Parent; + while (node) + { + result = !result; + node = node->Parent; + } + return result; +} +//------------------------------------------------------------------------------ + +bool PolyNode::IsOpen() const +{ + return m_IsOpen; +} +//------------------------------------------------------------------------------ + +#ifndef use_int32 + +//------------------------------------------------------------------------------ +// Int128 class (enables safe math on signed 64bit integers) +// eg Int128 val1((long64)9223372036854775807); //ie 2^63 -1 +// Int128 val2((long64)9223372036854775807); +// Int128 val3 = val1 * val2; +// val3.AsString => "85070591730234615847396907784232501249" (8.5e+37) +//------------------------------------------------------------------------------ + +class Int128 +{ + public: + ulong64 lo; + long64 hi; + + Int128(long64 _lo = 0) + { + lo = (ulong64)_lo; + if (_lo < 0) hi = -1; else hi = 0; + } + + + Int128(const Int128 &val): lo(val.lo), hi(val.hi){} + + Int128(const long64& _hi, const ulong64& _lo): lo(_lo), hi(_hi){} + + Int128& operator = (const long64 &val) + { + lo = (ulong64)val; + if (val < 0) hi = -1; else hi = 0; + return *this; + } + + bool operator == (const Int128 &val) const + {return (hi == val.hi && lo == val.lo);} + + bool operator != (const Int128 &val) const + { return !(*this == val);} + + bool operator > (const Int128 &val) const + { + if (hi != val.hi) + return hi > val.hi; + else + return lo > val.lo; + } + + bool operator < (const Int128 &val) const + { + if (hi != val.hi) + return hi < val.hi; + else + return lo < val.lo; + } + + bool operator >= (const Int128 &val) const + { return !(*this < val);} + + bool operator <= (const Int128 &val) const + { return !(*this > val);} + + Int128& operator += (const Int128 &rhs) + { + hi += rhs.hi; + lo += rhs.lo; + if (lo < rhs.lo) hi++; + return *this; + } + + Int128 operator + (const Int128 &rhs) const + { + Int128 result(*this); + result+= rhs; + return result; + } + + Int128& operator -= (const Int128 &rhs) + { + *this += -rhs; + return *this; + } + + Int128 operator - (const Int128 &rhs) const + { + Int128 result(*this); + result -= rhs; + return result; + } + + Int128 operator-() const //unary negation + { + if (lo == 0) + return Int128(-hi, 0); + else + return Int128(~hi, ~lo + 1); + } + + operator double() const + { + const double shift64 = 18446744073709551616.0; //2^64 + if (hi < 0) + { + if (lo == 0) return (double)hi * shift64; + else return -(double)(~lo + ~hi * shift64); + } + else + return (double)(lo + hi * shift64); + } + +}; +//------------------------------------------------------------------------------ + +Int128 Int128Mul (long64 lhs, long64 rhs) +{ + bool negate = (lhs < 0) != (rhs < 0); + + if (lhs < 0) lhs = -lhs; + ulong64 int1Hi = ulong64(lhs) >> 32; + ulong64 int1Lo = ulong64(lhs & 0xFFFFFFFF); + + if (rhs < 0) rhs = -rhs; + ulong64 int2Hi = ulong64(rhs) >> 32; + ulong64 int2Lo = ulong64(rhs & 0xFFFFFFFF); + + //nb: see comments in clipper.pas + ulong64 a = int1Hi * int2Hi; + ulong64 b = int1Lo * int2Lo; + ulong64 c = int1Hi * int2Lo + int1Lo * int2Hi; + + Int128 tmp; + tmp.hi = long64(a + (c >> 32)); + tmp.lo = long64(c << 32); + tmp.lo += long64(b); + if (tmp.lo < b) tmp.hi++; + if (negate) tmp = -tmp; + return tmp; +}; +#endif + +//------------------------------------------------------------------------------ +// Miscellaneous global functions +//------------------------------------------------------------------------------ + +bool Orientation(const Path &poly) +{ + return Area(poly) >= 0; +} +//------------------------------------------------------------------------------ + +double Area(const Path &poly) +{ + int size = (int)poly.size(); + if (size < 3) return 0; + + double a = 0; + for (int i = 0, j = size -1; i < size; ++i) + { + a += ((double)poly[j].X + poly[i].X) * ((double)poly[j].Y - poly[i].Y); + j = i; + } + return -a * 0.5; +} +//------------------------------------------------------------------------------ + +double Area(const OutPt *op) +{ + const OutPt *startOp = op; + if (!op) return 0; + double a = 0; + do { + a += (double)(op->Prev->Pt.X + op->Pt.X) * (double)(op->Prev->Pt.Y - op->Pt.Y); + op = op->Next; + } while (op != startOp); + return a * 0.5; +} +//------------------------------------------------------------------------------ + +double Area(const OutRec &outRec) +{ + return Area(outRec.Pts); +} +//------------------------------------------------------------------------------ + +bool PointIsVertex(const IntPoint &Pt, OutPt *pp) +{ + OutPt *pp2 = pp; + do + { + if (pp2->Pt == Pt) return true; + pp2 = pp2->Next; + } + while (pp2 != pp); + return false; +} +//------------------------------------------------------------------------------ + +//See "The Point in Polygon Problem for Arbitrary Polygons" by Hormann & Agathos +//http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.88.5498&rep=rep1&type=pdf +int PointInPolygon(const IntPoint &pt, const Path &path) +{ + //returns 0 if false, +1 if true, -1 if pt ON polygon boundary + int result = 0; + size_t cnt = path.size(); + if (cnt < 3) return 0; + IntPoint ip = path[0]; + for(size_t i = 1; i <= cnt; ++i) + { + IntPoint ipNext = (i == cnt ? path[0] : path[i]); + if (ipNext.Y == pt.Y) + { + if ((ipNext.X == pt.X) || (ip.Y == pt.Y && + ((ipNext.X > pt.X) == (ip.X < pt.X)))) return -1; + } + if ((ip.Y < pt.Y) != (ipNext.Y < pt.Y)) + { + if (ip.X >= pt.X) + { + if (ipNext.X > pt.X) result = 1 - result; + else + { + double d = (double)(ip.X - pt.X) * (ipNext.Y - pt.Y) - + (double)(ipNext.X - pt.X) * (ip.Y - pt.Y); + if (!d) return -1; + if ((d > 0) == (ipNext.Y > ip.Y)) result = 1 - result; + } + } else + { + if (ipNext.X > pt.X) + { + double d = (double)(ip.X - pt.X) * (ipNext.Y - pt.Y) - + (double)(ipNext.X - pt.X) * (ip.Y - pt.Y); + if (!d) return -1; + if ((d > 0) == (ipNext.Y > ip.Y)) result = 1 - result; + } + } + } + ip = ipNext; + } + return result; +} +//------------------------------------------------------------------------------ + +int PointInPolygon (const IntPoint &pt, OutPt *op) +{ + //returns 0 if false, +1 if true, -1 if pt ON polygon boundary + int result = 0; + OutPt* startOp = op; + for(;;) + { + if (op->Next->Pt.Y == pt.Y) + { + if ((op->Next->Pt.X == pt.X) || (op->Pt.Y == pt.Y && + ((op->Next->Pt.X > pt.X) == (op->Pt.X < pt.X)))) return -1; + } + if ((op->Pt.Y < pt.Y) != (op->Next->Pt.Y < pt.Y)) + { + if (op->Pt.X >= pt.X) + { + if (op->Next->Pt.X > pt.X) result = 1 - result; + else + { + double d = (double)(op->Pt.X - pt.X) * (op->Next->Pt.Y - pt.Y) - + (double)(op->Next->Pt.X - pt.X) * (op->Pt.Y - pt.Y); + if (!d) return -1; + if ((d > 0) == (op->Next->Pt.Y > op->Pt.Y)) result = 1 - result; + } + } else + { + if (op->Next->Pt.X > pt.X) + { + double d = (double)(op->Pt.X - pt.X) * (op->Next->Pt.Y - pt.Y) - + (double)(op->Next->Pt.X - pt.X) * (op->Pt.Y - pt.Y); + if (!d) return -1; + if ((d > 0) == (op->Next->Pt.Y > op->Pt.Y)) result = 1 - result; + } + } + } + op = op->Next; + if (startOp == op) break; + } + return result; +} +//------------------------------------------------------------------------------ + +bool Poly2ContainsPoly1(OutPt *OutPt1, OutPt *OutPt2) +{ + OutPt* op = OutPt1; + do + { + //nb: PointInPolygon returns 0 if false, +1 if true, -1 if pt on polygon + int res = PointInPolygon(op->Pt, OutPt2); + if (res >= 0) return res > 0; + op = op->Next; + } + while (op != OutPt1); + return true; +} +//---------------------------------------------------------------------- + +bool SlopesEqual(const TEdge &e1, const TEdge &e2, bool UseFullInt64Range) +{ +#ifndef use_int32 + if (UseFullInt64Range) + return Int128Mul(e1.Top.Y - e1.Bot.Y, e2.Top.X - e2.Bot.X) == + Int128Mul(e1.Top.X - e1.Bot.X, e2.Top.Y - e2.Bot.Y); + else +#endif + return (e1.Top.Y - e1.Bot.Y) * (e2.Top.X - e2.Bot.X) == + (e1.Top.X - e1.Bot.X) * (e2.Top.Y - e2.Bot.Y); +} +//------------------------------------------------------------------------------ + +bool SlopesEqual(const IntPoint pt1, const IntPoint pt2, + const IntPoint pt3, bool UseFullInt64Range) +{ +#ifndef use_int32 + if (UseFullInt64Range) + return Int128Mul(pt1.Y-pt2.Y, pt2.X-pt3.X) == Int128Mul(pt1.X-pt2.X, pt2.Y-pt3.Y); + else +#endif + return (pt1.Y-pt2.Y)*(pt2.X-pt3.X) == (pt1.X-pt2.X)*(pt2.Y-pt3.Y); +} +//------------------------------------------------------------------------------ + +bool SlopesEqual(const IntPoint pt1, const IntPoint pt2, + const IntPoint pt3, const IntPoint pt4, bool UseFullInt64Range) +{ +#ifndef use_int32 + if (UseFullInt64Range) + return Int128Mul(pt1.Y-pt2.Y, pt3.X-pt4.X) == Int128Mul(pt1.X-pt2.X, pt3.Y-pt4.Y); + else +#endif + return (pt1.Y-pt2.Y)*(pt3.X-pt4.X) == (pt1.X-pt2.X)*(pt3.Y-pt4.Y); +} +//------------------------------------------------------------------------------ + +inline bool IsHorizontal(TEdge &e) +{ + return e.Dx == HORIZONTAL; +} +//------------------------------------------------------------------------------ + +inline double GetDx(const IntPoint pt1, const IntPoint pt2) +{ + return (pt1.Y == pt2.Y) ? + HORIZONTAL : (double)(pt2.X - pt1.X) / (pt2.Y - pt1.Y); +} +//--------------------------------------------------------------------------- + +inline void SetDx(TEdge &e) +{ + cInt dy = (e.Top.Y - e.Bot.Y); + if (dy == 0) e.Dx = HORIZONTAL; + else e.Dx = (double)(e.Top.X - e.Bot.X) / dy; +} +//--------------------------------------------------------------------------- + +inline void SwapSides(TEdge &Edge1, TEdge &Edge2) +{ + EdgeSide Side = Edge1.Side; + Edge1.Side = Edge2.Side; + Edge2.Side = Side; +} +//------------------------------------------------------------------------------ + +inline void SwapPolyIndexes(TEdge &Edge1, TEdge &Edge2) +{ + int OutIdx = Edge1.OutIdx; + Edge1.OutIdx = Edge2.OutIdx; + Edge2.OutIdx = OutIdx; +} +//------------------------------------------------------------------------------ + +inline cInt TopX(TEdge &edge, const cInt currentY) +{ + return ( currentY == edge.Top.Y ) ? + edge.Top.X : edge.Bot.X + Round(edge.Dx *(currentY - edge.Bot.Y)); +} +//------------------------------------------------------------------------------ + +void IntersectPoint(TEdge &Edge1, TEdge &Edge2, IntPoint &ip) +{ +#ifdef use_xyz + ip.Z = 0; +#endif + + double b1, b2; + if (Edge1.Dx == Edge2.Dx) + { + ip.Y = Edge1.Curr.Y; + ip.X = TopX(Edge1, ip.Y); + return; + } + else if (Edge1.Dx == 0) + { + ip.X = Edge1.Bot.X; + if (IsHorizontal(Edge2)) + ip.Y = Edge2.Bot.Y; + else + { + b2 = Edge2.Bot.Y - (Edge2.Bot.X / Edge2.Dx); + ip.Y = Round(ip.X / Edge2.Dx + b2); + } + } + else if (Edge2.Dx == 0) + { + ip.X = Edge2.Bot.X; + if (IsHorizontal(Edge1)) + ip.Y = Edge1.Bot.Y; + else + { + b1 = Edge1.Bot.Y - (Edge1.Bot.X / Edge1.Dx); + ip.Y = Round(ip.X / Edge1.Dx + b1); + } + } + else + { + b1 = Edge1.Bot.X - Edge1.Bot.Y * Edge1.Dx; + b2 = Edge2.Bot.X - Edge2.Bot.Y * Edge2.Dx; + double q = (b2-b1) / (Edge1.Dx - Edge2.Dx); + ip.Y = Round(q); + if (std::fabs(Edge1.Dx) < std::fabs(Edge2.Dx)) + ip.X = Round(Edge1.Dx * q + b1); + else + ip.X = Round(Edge2.Dx * q + b2); + } + + if (ip.Y < Edge1.Top.Y || ip.Y < Edge2.Top.Y) + { + if (Edge1.Top.Y > Edge2.Top.Y) + ip.Y = Edge1.Top.Y; + else + ip.Y = Edge2.Top.Y; + if (std::fabs(Edge1.Dx) < std::fabs(Edge2.Dx)) + ip.X = TopX(Edge1, ip.Y); + else + ip.X = TopX(Edge2, ip.Y); + } + //finally, don't allow 'ip' to be BELOW curr.Y (ie bottom of scanbeam) ... + if (ip.Y > Edge1.Curr.Y) + { + ip.Y = Edge1.Curr.Y; + //use the more vertical edge to derive X ... + if (std::fabs(Edge1.Dx) > std::fabs(Edge2.Dx)) + ip.X = TopX(Edge2, ip.Y); else + ip.X = TopX(Edge1, ip.Y); + } +} +//------------------------------------------------------------------------------ + +void ReversePolyPtLinks(OutPt *pp) +{ + if (!pp) return; + OutPt *pp1, *pp2; + pp1 = pp; + do { + pp2 = pp1->Next; + pp1->Next = pp1->Prev; + pp1->Prev = pp2; + pp1 = pp2; + } while( pp1 != pp ); +} +//------------------------------------------------------------------------------ + +void DisposeOutPts(OutPt*& pp) +{ + if (pp == 0) return; + pp->Prev->Next = 0; + while( pp ) + { + OutPt *tmpPp = pp; + pp = pp->Next; + delete tmpPp; + } +} +//------------------------------------------------------------------------------ + +inline void InitEdge(TEdge* e, TEdge* eNext, TEdge* ePrev, const IntPoint& Pt) +{ + std::memset(e, 0, sizeof(TEdge)); + e->Next = eNext; + e->Prev = ePrev; + e->Curr = Pt; + e->OutIdx = Unassigned; +} +//------------------------------------------------------------------------------ + +void InitEdge2(TEdge& e, PolyType Pt) +{ + if (e.Curr.Y >= e.Next->Curr.Y) + { + e.Bot = e.Curr; + e.Top = e.Next->Curr; + } else + { + e.Top = e.Curr; + e.Bot = e.Next->Curr; + } + SetDx(e); + e.PolyTyp = Pt; +} +//------------------------------------------------------------------------------ + +TEdge* RemoveEdge(TEdge* e) +{ + //removes e from double_linked_list (but without removing from memory) + e->Prev->Next = e->Next; + e->Next->Prev = e->Prev; + TEdge* result = e->Next; + e->Prev = 0; //flag as removed (see ClipperBase.Clear) + return result; +} +//------------------------------------------------------------------------------ + +inline void ReverseHorizontal(TEdge &e) +{ + //swap horizontal edges' Top and Bottom x's so they follow the natural + //progression of the bounds - ie so their xbots will align with the + //adjoining lower edge. [Helpful in the ProcessHorizontal() method.] + std::swap(e.Top.X, e.Bot.X); +#ifdef use_xyz + std::swap(e.Top.Z, e.Bot.Z); +#endif +} +//------------------------------------------------------------------------------ + +void SwapPoints(IntPoint &pt1, IntPoint &pt2) +{ + IntPoint tmp = pt1; + pt1 = pt2; + pt2 = tmp; +} +//------------------------------------------------------------------------------ + +bool GetOverlapSegment(IntPoint pt1a, IntPoint pt1b, IntPoint pt2a, + IntPoint pt2b, IntPoint &pt1, IntPoint &pt2) +{ + //precondition: segments are Collinear. + if (Abs(pt1a.X - pt1b.X) > Abs(pt1a.Y - pt1b.Y)) + { + if (pt1a.X > pt1b.X) SwapPoints(pt1a, pt1b); + if (pt2a.X > pt2b.X) SwapPoints(pt2a, pt2b); + if (pt1a.X > pt2a.X) pt1 = pt1a; else pt1 = pt2a; + if (pt1b.X < pt2b.X) pt2 = pt1b; else pt2 = pt2b; + return pt1.X < pt2.X; + } else + { + if (pt1a.Y < pt1b.Y) SwapPoints(pt1a, pt1b); + if (pt2a.Y < pt2b.Y) SwapPoints(pt2a, pt2b); + if (pt1a.Y < pt2a.Y) pt1 = pt1a; else pt1 = pt2a; + if (pt1b.Y > pt2b.Y) pt2 = pt1b; else pt2 = pt2b; + return pt1.Y > pt2.Y; + } +} +//------------------------------------------------------------------------------ + +bool FirstIsBottomPt(const OutPt* btmPt1, const OutPt* btmPt2) +{ + OutPt *p = btmPt1->Prev; + while ((p->Pt == btmPt1->Pt) && (p != btmPt1)) p = p->Prev; + double dx1p = std::fabs(GetDx(btmPt1->Pt, p->Pt)); + p = btmPt1->Next; + while ((p->Pt == btmPt1->Pt) && (p != btmPt1)) p = p->Next; + double dx1n = std::fabs(GetDx(btmPt1->Pt, p->Pt)); + + p = btmPt2->Prev; + while ((p->Pt == btmPt2->Pt) && (p != btmPt2)) p = p->Prev; + double dx2p = std::fabs(GetDx(btmPt2->Pt, p->Pt)); + p = btmPt2->Next; + while ((p->Pt == btmPt2->Pt) && (p != btmPt2)) p = p->Next; + double dx2n = std::fabs(GetDx(btmPt2->Pt, p->Pt)); + + if (std::max(dx1p, dx1n) == std::max(dx2p, dx2n) && + std::min(dx1p, dx1n) == std::min(dx2p, dx2n)) + return Area(btmPt1) > 0; //if otherwise identical use orientation + else + return (dx1p >= dx2p && dx1p >= dx2n) || (dx1n >= dx2p && dx1n >= dx2n); +} +//------------------------------------------------------------------------------ + +OutPt* GetBottomPt(OutPt *pp) +{ + OutPt* dups = 0; + OutPt* p = pp->Next; + while (p != pp) + { + if (p->Pt.Y > pp->Pt.Y) + { + pp = p; + dups = 0; + } + else if (p->Pt.Y == pp->Pt.Y && p->Pt.X <= pp->Pt.X) + { + if (p->Pt.X < pp->Pt.X) + { + dups = 0; + pp = p; + } else + { + if (p->Next != pp && p->Prev != pp) dups = p; + } + } + p = p->Next; + } + if (dups) + { + //there appears to be at least 2 vertices at BottomPt so ... + while (dups != p) + { + if (!FirstIsBottomPt(p, dups)) pp = dups; + dups = dups->Next; + while (dups->Pt != pp->Pt) dups = dups->Next; + } + } + return pp; +} +//------------------------------------------------------------------------------ + +bool Pt2IsBetweenPt1AndPt3(const IntPoint pt1, + const IntPoint pt2, const IntPoint pt3) +{ + if ((pt1 == pt3) || (pt1 == pt2) || (pt3 == pt2)) + return false; + else if (pt1.X != pt3.X) + return (pt2.X > pt1.X) == (pt2.X < pt3.X); + else + return (pt2.Y > pt1.Y) == (pt2.Y < pt3.Y); +} +//------------------------------------------------------------------------------ + +bool HorzSegmentsOverlap(cInt seg1a, cInt seg1b, cInt seg2a, cInt seg2b) +{ + if (seg1a > seg1b) std::swap(seg1a, seg1b); + if (seg2a > seg2b) std::swap(seg2a, seg2b); + return (seg1a < seg2b) && (seg2a < seg1b); +} + +//------------------------------------------------------------------------------ +// ClipperBase class methods ... +//------------------------------------------------------------------------------ + +ClipperBase::ClipperBase() //constructor +{ + m_CurrentLM = m_MinimaList.begin(); //begin() == end() here + m_UseFullRange = false; + + // Avoid uninitialized vars + m_PreserveCollinear = false; + m_HasOpenPaths = false; + m_ActiveEdges = NULL; +} +//------------------------------------------------------------------------------ + +ClipperBase::~ClipperBase() //destructor +{ + Clear(); +} +//------------------------------------------------------------------------------ + +void RangeTest(const IntPoint& Pt, bool& useFullRange) +{ + if (useFullRange) + { + if (Pt.X > hiRange || Pt.Y > hiRange || -Pt.X > hiRange || -Pt.Y > hiRange) + throw clipperException("Coordinate outside allowed range"); + } + else if (Pt.X > loRange|| Pt.Y > loRange || -Pt.X > loRange || -Pt.Y > loRange) + { + useFullRange = true; + RangeTest(Pt, useFullRange); + } +} +//------------------------------------------------------------------------------ + +TEdge* FindNextLocMin(TEdge* E) +{ + for (;;) + { + while (E->Bot != E->Prev->Bot || E->Curr == E->Top) E = E->Next; + if (!IsHorizontal(*E) && !IsHorizontal(*E->Prev)) break; + while (IsHorizontal(*E->Prev)) E = E->Prev; + TEdge* E2 = E; + while (IsHorizontal(*E)) E = E->Next; + if (E->Top.Y == E->Prev->Bot.Y) continue; //ie just an intermediate horz. + if (E2->Prev->Bot.X < E->Bot.X) E = E2; + break; + } + return E; +} +//------------------------------------------------------------------------------ + +TEdge* ClipperBase::ProcessBound(TEdge* E, bool NextIsForward) +{ + TEdge *Result = E; + TEdge *Horz = 0; + + if (E->OutIdx == Skip) + { + //if edges still remain in the current bound beyond the skip edge then + //create another LocMin and call ProcessBound once more + if (NextIsForward) + { + while (E->Top.Y == E->Next->Bot.Y) E = E->Next; + //don't include top horizontals when parsing a bound a second time, + //they will be contained in the opposite bound ... + while (E != Result && IsHorizontal(*E)) E = E->Prev; + } + else + { + while (E->Top.Y == E->Prev->Bot.Y) E = E->Prev; + while (E != Result && IsHorizontal(*E)) E = E->Next; + } + + if (E == Result) + { + if (NextIsForward) Result = E->Next; + else Result = E->Prev; + } + else + { + //there are more edges in the bound beyond result starting with E + if (NextIsForward) + E = Result->Next; + else + E = Result->Prev; + MinimaList::value_type locMin; + locMin.Y = E->Bot.Y; + locMin.LeftBound = 0; + locMin.RightBound = E; + E->WindDelta = 0; + Result = ProcessBound(E, NextIsForward); + m_MinimaList.push_back(locMin); + } + return Result; + } + + TEdge *EStart; + + if (IsHorizontal(*E)) + { + //We need to be careful with open paths because this may not be a + //true local minima (ie E may be following a skip edge). + //Also, consecutive horz. edges may start heading left before going right. + if (NextIsForward) + EStart = E->Prev; + else + EStart = E->Next; + if (IsHorizontal(*EStart)) //ie an adjoining horizontal skip edge + { + if (EStart->Bot.X != E->Bot.X && EStart->Top.X != E->Bot.X) + ReverseHorizontal(*E); + } + else if (EStart->Bot.X != E->Bot.X) + ReverseHorizontal(*E); + } + + EStart = E; + if (NextIsForward) + { + while (Result->Top.Y == Result->Next->Bot.Y && Result->Next->OutIdx != Skip) + Result = Result->Next; + if (IsHorizontal(*Result) && Result->Next->OutIdx != Skip) + { + //nb: at the top of a bound, horizontals are added to the bound + //only when the preceding edge attaches to the horizontal's left vertex + //unless a Skip edge is encountered when that becomes the top divide + Horz = Result; + while (IsHorizontal(*Horz->Prev)) Horz = Horz->Prev; + if (Horz->Prev->Top.X > Result->Next->Top.X) Result = Horz->Prev; + } + while (E != Result) + { + E->NextInLML = E->Next; + if (IsHorizontal(*E) && E != EStart && + E->Bot.X != E->Prev->Top.X) ReverseHorizontal(*E); + E = E->Next; + } + if (IsHorizontal(*E) && E != EStart && E->Bot.X != E->Prev->Top.X) + ReverseHorizontal(*E); + Result = Result->Next; //move to the edge just beyond current bound + } else + { + while (Result->Top.Y == Result->Prev->Bot.Y && Result->Prev->OutIdx != Skip) + Result = Result->Prev; + if (IsHorizontal(*Result) && Result->Prev->OutIdx != Skip) + { + Horz = Result; + while (IsHorizontal(*Horz->Next)) Horz = Horz->Next; + if (Horz->Next->Top.X == Result->Prev->Top.X || + Horz->Next->Top.X > Result->Prev->Top.X) Result = Horz->Next; + } + + while (E != Result) + { + E->NextInLML = E->Prev; + if (IsHorizontal(*E) && E != EStart && E->Bot.X != E->Next->Top.X) + ReverseHorizontal(*E); + E = E->Prev; + } + if (IsHorizontal(*E) && E != EStart && E->Bot.X != E->Next->Top.X) + ReverseHorizontal(*E); + Result = Result->Prev; //move to the edge just beyond current bound + } + + return Result; +} +//------------------------------------------------------------------------------ + +bool ClipperBase::AddPath(const Path &pg, PolyType PolyTyp, bool Closed) +{ +#ifdef use_lines + if (!Closed && PolyTyp == ptClip) + throw clipperException("AddPath: Open paths must be subject."); +#else + if (!Closed) + throw clipperException("AddPath: Open paths have been disabled."); +#endif + + int highI = (int)pg.size() -1; + if (Closed) while (highI > 0 && (pg[highI] == pg[0])) --highI; + while (highI > 0 && (pg[highI] == pg[highI -1])) --highI; + if ((Closed && highI < 2) || (!Closed && highI < 1)) return false; + + //create a new edge array ... + TEdge *edges = new TEdge [highI +1]; + + bool IsFlat = true; + //1. Basic (first) edge initialization ... + try + { + edges[1].Curr = pg[1]; + RangeTest(pg[0], m_UseFullRange); + RangeTest(pg[highI], m_UseFullRange); + InitEdge(&edges[0], &edges[1], &edges[highI], pg[0]); + InitEdge(&edges[highI], &edges[0], &edges[highI-1], pg[highI]); + for (int i = highI - 1; i >= 1; --i) + { + RangeTest(pg[i], m_UseFullRange); + InitEdge(&edges[i], &edges[i+1], &edges[i-1], pg[i]); + } + } + catch(...) + { + delete [] edges; + throw; //range test fails + } + TEdge *eStart = &edges[0]; + + //2. Remove duplicate vertices, and (when closed) collinear edges ... + TEdge *E = eStart, *eLoopStop = eStart; + for (;;) + { + //nb: allows matching start and end points when not Closed ... + if (E->Curr == E->Next->Curr && (Closed || E->Next != eStart)) + { + if (E == E->Next) break; + if (E == eStart) eStart = E->Next; + E = RemoveEdge(E); + eLoopStop = E; + continue; + } + if (E->Prev == E->Next) + break; //only two vertices + else if (Closed && + SlopesEqual(E->Prev->Curr, E->Curr, E->Next->Curr, m_UseFullRange) && + (!m_PreserveCollinear || + !Pt2IsBetweenPt1AndPt3(E->Prev->Curr, E->Curr, E->Next->Curr))) + { + //Collinear edges are allowed for open paths but in closed paths + //the default is to merge adjacent collinear edges into a single edge. + //However, if the PreserveCollinear property is enabled, only overlapping + //collinear edges (ie spikes) will be removed from closed paths. + if (E == eStart) eStart = E->Next; + E = RemoveEdge(E); + E = E->Prev; + eLoopStop = E; + continue; + } + E = E->Next; + if ((E == eLoopStop) || (!Closed && E->Next == eStart)) break; + } + + if ((!Closed && (E == E->Next)) || (Closed && (E->Prev == E->Next))) + { + delete [] edges; + return false; + } + + if (!Closed) + { + m_HasOpenPaths = true; + eStart->Prev->OutIdx = Skip; + } + + //3. Do second stage of edge initialization ... + E = eStart; + do + { + InitEdge2(*E, PolyTyp); + E = E->Next; + if (IsFlat && E->Curr.Y != eStart->Curr.Y) IsFlat = false; + } + while (E != eStart); + + //4. Finally, add edge bounds to LocalMinima list ... + + //Totally flat paths must be handled differently when adding them + //to LocalMinima list to avoid endless loops etc ... + if (IsFlat) + { + if (Closed) + { + delete [] edges; + return false; + } + E->Prev->OutIdx = Skip; + MinimaList::value_type locMin; + locMin.Y = E->Bot.Y; + locMin.LeftBound = 0; + locMin.RightBound = E; + locMin.RightBound->Side = esRight; + locMin.RightBound->WindDelta = 0; + for (;;) + { + if (E->Bot.X != E->Prev->Top.X) ReverseHorizontal(*E); + if (E->Next->OutIdx == Skip) break; + E->NextInLML = E->Next; + E = E->Next; + } + m_MinimaList.push_back(locMin); + m_edges.push_back(edges); + return true; + } + + m_edges.push_back(edges); + bool leftBoundIsForward; + TEdge* EMin = 0; + + //workaround to avoid an endless loop in the while loop below when + //open paths have matching start and end points ... + if (E->Prev->Bot == E->Prev->Top) E = E->Next; + + for (;;) + { + E = FindNextLocMin(E); + if (E == EMin) break; + else if (!EMin) EMin = E; + + //E and E.Prev now share a local minima (left aligned if horizontal). + //Compare their slopes to find which starts which bound ... + MinimaList::value_type locMin; + locMin.Y = E->Bot.Y; + if (E->Dx < E->Prev->Dx) + { + locMin.LeftBound = E->Prev; + locMin.RightBound = E; + leftBoundIsForward = false; //Q.nextInLML = Q.prev + } else + { + locMin.LeftBound = E; + locMin.RightBound = E->Prev; + leftBoundIsForward = true; //Q.nextInLML = Q.next + } + + if (!Closed) locMin.LeftBound->WindDelta = 0; + else if (locMin.LeftBound->Next == locMin.RightBound) + locMin.LeftBound->WindDelta = -1; + else locMin.LeftBound->WindDelta = 1; + locMin.RightBound->WindDelta = -locMin.LeftBound->WindDelta; + + E = ProcessBound(locMin.LeftBound, leftBoundIsForward); + if (E->OutIdx == Skip) E = ProcessBound(E, leftBoundIsForward); + + TEdge* E2 = ProcessBound(locMin.RightBound, !leftBoundIsForward); + if (E2->OutIdx == Skip) E2 = ProcessBound(E2, !leftBoundIsForward); + + if (locMin.LeftBound->OutIdx == Skip) + locMin.LeftBound = 0; + else if (locMin.RightBound->OutIdx == Skip) + locMin.RightBound = 0; + m_MinimaList.push_back(locMin); + if (!leftBoundIsForward) E = E2; + } + return true; +} +//------------------------------------------------------------------------------ + +bool ClipperBase::AddPaths(const Paths &ppg, PolyType PolyTyp, bool Closed) +{ + bool result = false; + for (Paths::size_type i = 0; i < ppg.size(); ++i) + if (AddPath(ppg[i], PolyTyp, Closed)) result = true; + return result; +} +//------------------------------------------------------------------------------ + +void ClipperBase::Clear() +{ + DisposeLocalMinimaList(); + for (EdgeList::size_type i = 0; i < m_edges.size(); ++i) + { + TEdge* edges = m_edges[i]; + delete [] edges; + } + m_edges.clear(); + m_UseFullRange = false; + m_HasOpenPaths = false; +} +//------------------------------------------------------------------------------ + +void ClipperBase::Reset() +{ + m_CurrentLM = m_MinimaList.begin(); + if (m_CurrentLM == m_MinimaList.end()) return; //ie nothing to process + std::sort(m_MinimaList.begin(), m_MinimaList.end(), LocMinSorter()); + + m_Scanbeam = ScanbeamList(); //clears/resets priority_queue + //reset all edges ... + for (MinimaList::iterator lm = m_MinimaList.begin(); lm != m_MinimaList.end(); ++lm) + { + InsertScanbeam(lm->Y); + TEdge* e = lm->LeftBound; + if (e) + { + e->Curr = e->Bot; + e->Side = esLeft; + e->OutIdx = Unassigned; + } + + e = lm->RightBound; + if (e) + { + e->Curr = e->Bot; + e->Side = esRight; + e->OutIdx = Unassigned; + } + } + m_ActiveEdges = 0; + m_CurrentLM = m_MinimaList.begin(); +} +//------------------------------------------------------------------------------ + +void ClipperBase::DisposeLocalMinimaList() +{ + m_MinimaList.clear(); + m_CurrentLM = m_MinimaList.begin(); +} +//------------------------------------------------------------------------------ + +bool ClipperBase::PopLocalMinima(cInt Y, const LocalMinimum *&locMin) +{ + if (m_CurrentLM == m_MinimaList.end() || (*m_CurrentLM).Y != Y) return false; + locMin = &(*m_CurrentLM); + ++m_CurrentLM; + return true; +} +//------------------------------------------------------------------------------ + +IntRect ClipperBase::GetBounds() +{ + IntRect result; + MinimaList::iterator lm = m_MinimaList.begin(); + if (lm == m_MinimaList.end()) + { + result.left = result.top = result.right = result.bottom = 0; + return result; + } + result.left = lm->LeftBound->Bot.X; + result.top = lm->LeftBound->Bot.Y; + result.right = lm->LeftBound->Bot.X; + result.bottom = lm->LeftBound->Bot.Y; + while (lm != m_MinimaList.end()) + { + //todo - needs fixing for open paths + result.bottom = std::max(result.bottom, lm->LeftBound->Bot.Y); + TEdge* e = lm->LeftBound; + for (;;) { + TEdge* bottomE = e; + while (e->NextInLML) + { + if (e->Bot.X < result.left) result.left = e->Bot.X; + if (e->Bot.X > result.right) result.right = e->Bot.X; + e = e->NextInLML; + } + result.left = std::min(result.left, e->Bot.X); + result.right = std::max(result.right, e->Bot.X); + result.left = std::min(result.left, e->Top.X); + result.right = std::max(result.right, e->Top.X); + result.top = std::min(result.top, e->Top.Y); + if (bottomE == lm->LeftBound) e = lm->RightBound; + else break; + } + ++lm; + } + return result; +} +//------------------------------------------------------------------------------ + +void ClipperBase::InsertScanbeam(const cInt Y) +{ + m_Scanbeam.push(Y); +} +//------------------------------------------------------------------------------ + +bool ClipperBase::PopScanbeam(cInt &Y) +{ + if (m_Scanbeam.empty()) return false; + Y = m_Scanbeam.top(); + m_Scanbeam.pop(); + while (!m_Scanbeam.empty() && Y == m_Scanbeam.top()) { m_Scanbeam.pop(); } // Pop duplicates. + return true; +} +//------------------------------------------------------------------------------ + +void ClipperBase::DisposeAllOutRecs(){ + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + DisposeOutRec(i); + m_PolyOuts.clear(); +} +//------------------------------------------------------------------------------ + +void ClipperBase::DisposeOutRec(PolyOutList::size_type index) +{ + OutRec *outRec = m_PolyOuts[index]; + if (outRec->Pts) DisposeOutPts(outRec->Pts); + delete outRec; + m_PolyOuts[index] = 0; +} +//------------------------------------------------------------------------------ + +void ClipperBase::DeleteFromAEL(TEdge *e) +{ + TEdge* AelPrev = e->PrevInAEL; + TEdge* AelNext = e->NextInAEL; + if (!AelPrev && !AelNext && (e != m_ActiveEdges)) return; //already deleted + if (AelPrev) AelPrev->NextInAEL = AelNext; + else m_ActiveEdges = AelNext; + if (AelNext) AelNext->PrevInAEL = AelPrev; + e->NextInAEL = 0; + e->PrevInAEL = 0; +} +//------------------------------------------------------------------------------ + +OutRec* ClipperBase::CreateOutRec() +{ + OutRec* result = new OutRec; + result->IsHole = false; + result->IsOpen = false; + result->FirstLeft = 0; + result->Pts = 0; + result->BottomPt = 0; + result->PolyNd = 0; + m_PolyOuts.push_back(result); + result->Idx = (int)m_PolyOuts.size() - 1; + return result; +} +//------------------------------------------------------------------------------ + +void ClipperBase::SwapPositionsInAEL(TEdge *Edge1, TEdge *Edge2) +{ + //check that one or other edge hasn't already been removed from AEL ... + if (Edge1->NextInAEL == Edge1->PrevInAEL || + Edge2->NextInAEL == Edge2->PrevInAEL) return; + + if (Edge1->NextInAEL == Edge2) + { + TEdge* Next = Edge2->NextInAEL; + if (Next) Next->PrevInAEL = Edge1; + TEdge* Prev = Edge1->PrevInAEL; + if (Prev) Prev->NextInAEL = Edge2; + Edge2->PrevInAEL = Prev; + Edge2->NextInAEL = Edge1; + Edge1->PrevInAEL = Edge2; + Edge1->NextInAEL = Next; + } + else if (Edge2->NextInAEL == Edge1) + { + TEdge* Next = Edge1->NextInAEL; + if (Next) Next->PrevInAEL = Edge2; + TEdge* Prev = Edge2->PrevInAEL; + if (Prev) Prev->NextInAEL = Edge1; + Edge1->PrevInAEL = Prev; + Edge1->NextInAEL = Edge2; + Edge2->PrevInAEL = Edge1; + Edge2->NextInAEL = Next; + } + else + { + TEdge* Next = Edge1->NextInAEL; + TEdge* Prev = Edge1->PrevInAEL; + Edge1->NextInAEL = Edge2->NextInAEL; + if (Edge1->NextInAEL) Edge1->NextInAEL->PrevInAEL = Edge1; + Edge1->PrevInAEL = Edge2->PrevInAEL; + if (Edge1->PrevInAEL) Edge1->PrevInAEL->NextInAEL = Edge1; + Edge2->NextInAEL = Next; + if (Edge2->NextInAEL) Edge2->NextInAEL->PrevInAEL = Edge2; + Edge2->PrevInAEL = Prev; + if (Edge2->PrevInAEL) Edge2->PrevInAEL->NextInAEL = Edge2; + } + + if (!Edge1->PrevInAEL) m_ActiveEdges = Edge1; + else if (!Edge2->PrevInAEL) m_ActiveEdges = Edge2; +} +//------------------------------------------------------------------------------ + +void ClipperBase::UpdateEdgeIntoAEL(TEdge *&e) +{ + if (!e->NextInLML) + throw clipperException("UpdateEdgeIntoAEL: invalid call"); + + e->NextInLML->OutIdx = e->OutIdx; + TEdge* AelPrev = e->PrevInAEL; + TEdge* AelNext = e->NextInAEL; + if (AelPrev) AelPrev->NextInAEL = e->NextInLML; + else m_ActiveEdges = e->NextInLML; + if (AelNext) AelNext->PrevInAEL = e->NextInLML; + e->NextInLML->Side = e->Side; + e->NextInLML->WindDelta = e->WindDelta; + e->NextInLML->WindCnt = e->WindCnt; + e->NextInLML->WindCnt2 = e->WindCnt2; + e = e->NextInLML; + e->Curr = e->Bot; + e->PrevInAEL = AelPrev; + e->NextInAEL = AelNext; + if (!IsHorizontal(*e)) InsertScanbeam(e->Top.Y); +} +//------------------------------------------------------------------------------ + +bool ClipperBase::LocalMinimaPending() +{ + return (m_CurrentLM != m_MinimaList.end()); +} + +//------------------------------------------------------------------------------ +// TClipper methods ... +//------------------------------------------------------------------------------ + +Clipper::Clipper(int initOptions) : ClipperBase() //constructor +{ + m_ExecuteLocked = false; + m_UseFullRange = false; + m_ReverseOutput = ((initOptions & ioReverseSolution) != 0); + m_StrictSimple = ((initOptions & ioStrictlySimple) != 0); + m_PreserveCollinear = ((initOptions & ioPreserveCollinear) != 0); + m_HasOpenPaths = false; +#ifdef use_xyz + m_ZFill = 0; +#endif + + // Avoid uninitialized vars + m_ClipType = ctIntersection; + m_SortedEdges = NULL; + m_ClipFillType = pftEvenOdd; + m_SubjFillType = pftEvenOdd; + m_UsingPolyTree = true; +} +//------------------------------------------------------------------------------ + +#ifdef use_xyz +void Clipper::ZFillFunction(ZFillCallback zFillFunc) +{ + m_ZFill = zFillFunc; +} +//------------------------------------------------------------------------------ +#endif + +bool Clipper::Execute(ClipType clipType, Paths &solution, PolyFillType fillType) +{ + return Execute(clipType, solution, fillType, fillType); +} +//------------------------------------------------------------------------------ + +bool Clipper::Execute(ClipType clipType, PolyTree &polytree, PolyFillType fillType) +{ + return Execute(clipType, polytree, fillType, fillType); +} +//------------------------------------------------------------------------------ + +bool Clipper::Execute(ClipType clipType, Paths &solution, + PolyFillType subjFillType, PolyFillType clipFillType) +{ + if( m_ExecuteLocked ) return false; + if (m_HasOpenPaths) + throw clipperException("Error: PolyTree struct is needed for open path clipping."); + m_ExecuteLocked = true; + solution.resize(0); + m_SubjFillType = subjFillType; + m_ClipFillType = clipFillType; + m_ClipType = clipType; + m_UsingPolyTree = false; + bool succeeded = ExecuteInternal(); + if (succeeded) BuildResult(solution); + DisposeAllOutRecs(); + m_ExecuteLocked = false; + return succeeded; +} +//------------------------------------------------------------------------------ + +bool Clipper::Execute(ClipType clipType, PolyTree& polytree, + PolyFillType subjFillType, PolyFillType clipFillType) +{ + if( m_ExecuteLocked ) return false; + m_ExecuteLocked = true; + m_SubjFillType = subjFillType; + m_ClipFillType = clipFillType; + m_ClipType = clipType; + m_UsingPolyTree = true; + bool succeeded = ExecuteInternal(); + if (succeeded) BuildResult2(polytree); + DisposeAllOutRecs(); + m_ExecuteLocked = false; + return succeeded; +} +//------------------------------------------------------------------------------ + +void Clipper::FixHoleLinkage(OutRec &outrec) +{ + //skip OutRecs that (a) contain outermost polygons or + //(b) already have the correct owner/child linkage ... + if (!outrec.FirstLeft || + (outrec.IsHole != outrec.FirstLeft->IsHole && + outrec.FirstLeft->Pts)) return; + + OutRec* orfl = outrec.FirstLeft; + while (orfl && ((orfl->IsHole == outrec.IsHole) || !orfl->Pts)) + orfl = orfl->FirstLeft; + outrec.FirstLeft = orfl; +} +//------------------------------------------------------------------------------ + +bool Clipper::ExecuteInternal() +{ + bool succeeded = true; + try { + Reset(); + m_Maxima = MaximaList(); + m_SortedEdges = 0; + + succeeded = true; + cInt botY, topY; + if (!PopScanbeam(botY)) return false; + InsertLocalMinimaIntoAEL(botY); + while (PopScanbeam(topY) || LocalMinimaPending()) + { + ProcessHorizontals(); + ClearGhostJoins(); + if (!ProcessIntersections(topY)) + { + succeeded = false; + break; + } + ProcessEdgesAtTopOfScanbeam(topY); + botY = topY; + InsertLocalMinimaIntoAEL(botY); + } + } + catch(...) + { + succeeded = false; + } + + if (succeeded) + { + //fix orientations ... + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + { + OutRec *outRec = m_PolyOuts[i]; + if (!outRec->Pts || outRec->IsOpen) continue; + if ((outRec->IsHole ^ m_ReverseOutput) == (Area(*outRec) > 0)) + ReversePolyPtLinks(outRec->Pts); + } + + if (!m_Joins.empty()) JoinCommonEdges(); + + //unfortunately FixupOutPolygon() must be done after JoinCommonEdges() + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + { + OutRec *outRec = m_PolyOuts[i]; + if (!outRec->Pts) continue; + if (outRec->IsOpen) + FixupOutPolyline(*outRec); + else + FixupOutPolygon(*outRec); + } + + if (m_StrictSimple) DoSimplePolygons(); + } + + ClearJoins(); + ClearGhostJoins(); + return succeeded; +} +//------------------------------------------------------------------------------ + +void Clipper::SetWindingCount(TEdge &edge) +{ + TEdge *e = edge.PrevInAEL; + //find the edge of the same polytype that immediately preceeds 'edge' in AEL + while (e && ((e->PolyTyp != edge.PolyTyp) || (e->WindDelta == 0))) e = e->PrevInAEL; + if (!e) + { + if (edge.WindDelta == 0) + { + PolyFillType pft = (edge.PolyTyp == ptSubject ? m_SubjFillType : m_ClipFillType); + edge.WindCnt = (pft == pftNegative ? -1 : 1); + } + else + edge.WindCnt = edge.WindDelta; + edge.WindCnt2 = 0; + e = m_ActiveEdges; //ie get ready to calc WindCnt2 + } + else if (edge.WindDelta == 0 && m_ClipType != ctUnion) + { + edge.WindCnt = 1; + edge.WindCnt2 = e->WindCnt2; + e = e->NextInAEL; //ie get ready to calc WindCnt2 + } + else if (IsEvenOddFillType(edge)) + { + //EvenOdd filling ... + if (edge.WindDelta == 0) + { + //are we inside a subj polygon ... + bool Inside = true; + TEdge *e2 = e->PrevInAEL; + while (e2) + { + if (e2->PolyTyp == e->PolyTyp && e2->WindDelta != 0) + Inside = !Inside; + e2 = e2->PrevInAEL; + } + edge.WindCnt = (Inside ? 0 : 1); + } + else + { + edge.WindCnt = edge.WindDelta; + } + edge.WindCnt2 = e->WindCnt2; + e = e->NextInAEL; //ie get ready to calc WindCnt2 + } + else + { + //nonZero, Positive or Negative filling ... + if (e->WindCnt * e->WindDelta < 0) + { + //prev edge is 'decreasing' WindCount (WC) toward zero + //so we're outside the previous polygon ... + if (Abs(e->WindCnt) > 1) + { + //outside prev poly but still inside another. + //when reversing direction of prev poly use the same WC + if (e->WindDelta * edge.WindDelta < 0) edge.WindCnt = e->WindCnt; + //otherwise continue to 'decrease' WC ... + else edge.WindCnt = e->WindCnt + edge.WindDelta; + } + else + //now outside all polys of same polytype so set own WC ... + edge.WindCnt = (edge.WindDelta == 0 ? 1 : edge.WindDelta); + } else + { + //prev edge is 'increasing' WindCount (WC) away from zero + //so we're inside the previous polygon ... + if (edge.WindDelta == 0) + edge.WindCnt = (e->WindCnt < 0 ? e->WindCnt - 1 : e->WindCnt + 1); + //if wind direction is reversing prev then use same WC + else if (e->WindDelta * edge.WindDelta < 0) edge.WindCnt = e->WindCnt; + //otherwise add to WC ... + else edge.WindCnt = e->WindCnt + edge.WindDelta; + } + edge.WindCnt2 = e->WindCnt2; + e = e->NextInAEL; //ie get ready to calc WindCnt2 + } + + //update WindCnt2 ... + if (IsEvenOddAltFillType(edge)) + { + //EvenOdd filling ... + while (e != &edge) + { + if (e->WindDelta != 0) + edge.WindCnt2 = (edge.WindCnt2 == 0 ? 1 : 0); + e = e->NextInAEL; + } + } else + { + //nonZero, Positive or Negative filling ... + while ( e != &edge ) + { + edge.WindCnt2 += e->WindDelta; + e = e->NextInAEL; + } + } +} +//------------------------------------------------------------------------------ + +bool Clipper::IsEvenOddFillType(const TEdge& edge) const +{ + if (edge.PolyTyp == ptSubject) + return m_SubjFillType == pftEvenOdd; else + return m_ClipFillType == pftEvenOdd; +} +//------------------------------------------------------------------------------ + +bool Clipper::IsEvenOddAltFillType(const TEdge& edge) const +{ + if (edge.PolyTyp == ptSubject) + return m_ClipFillType == pftEvenOdd; else + return m_SubjFillType == pftEvenOdd; +} +//------------------------------------------------------------------------------ + +bool Clipper::IsContributing(const TEdge& edge) const +{ + PolyFillType pft, pft2; + if (edge.PolyTyp == ptSubject) + { + pft = m_SubjFillType; + pft2 = m_ClipFillType; + } else + { + pft = m_ClipFillType; + pft2 = m_SubjFillType; + } + + switch(pft) + { + case pftEvenOdd: + //return false if a subj line has been flagged as inside a subj polygon + if (edge.WindDelta == 0 && edge.WindCnt != 1) return false; + break; + case pftNonZero: + if (Abs(edge.WindCnt) != 1) return false; + break; + case pftPositive: + if (edge.WindCnt != 1) return false; + break; + default: //pftNegative + if (edge.WindCnt != -1) return false; + } + + switch(m_ClipType) + { + case ctIntersection: + switch(pft2) + { + case pftEvenOdd: + case pftNonZero: + return (edge.WindCnt2 != 0); + case pftPositive: + return (edge.WindCnt2 > 0); + default: + return (edge.WindCnt2 < 0); + } + break; + case ctUnion: + switch(pft2) + { + case pftEvenOdd: + case pftNonZero: + return (edge.WindCnt2 == 0); + case pftPositive: + return (edge.WindCnt2 <= 0); + default: + return (edge.WindCnt2 >= 0); + } + break; + case ctDifference: + if (edge.PolyTyp == ptSubject) + switch(pft2) + { + case pftEvenOdd: + case pftNonZero: + return (edge.WindCnt2 == 0); + case pftPositive: + return (edge.WindCnt2 <= 0); + default: + return (edge.WindCnt2 >= 0); + } + else + switch(pft2) + { + case pftEvenOdd: + case pftNonZero: + return (edge.WindCnt2 != 0); + case pftPositive: + return (edge.WindCnt2 > 0); + default: + return (edge.WindCnt2 < 0); + } + break; + case ctXor: + if (edge.WindDelta == 0) //XOr always contributing unless open + switch(pft2) + { + case pftEvenOdd: + case pftNonZero: + return (edge.WindCnt2 == 0); + case pftPositive: + return (edge.WindCnt2 <= 0); + default: + return (edge.WindCnt2 >= 0); + } + else + return true; + break; + default: + return true; + } +} +//------------------------------------------------------------------------------ + +OutPt* Clipper::AddLocalMinPoly(TEdge *e1, TEdge *e2, const IntPoint &Pt) +{ + OutPt* result; + TEdge *e, *prevE; + if (IsHorizontal(*e2) || ( e1->Dx > e2->Dx )) + { + result = AddOutPt(e1, Pt); + e2->OutIdx = e1->OutIdx; + e1->Side = esLeft; + e2->Side = esRight; + e = e1; + if (e->PrevInAEL == e2) + prevE = e2->PrevInAEL; + else + prevE = e->PrevInAEL; + } else + { + result = AddOutPt(e2, Pt); + e1->OutIdx = e2->OutIdx; + e1->Side = esRight; + e2->Side = esLeft; + e = e2; + if (e->PrevInAEL == e1) + prevE = e1->PrevInAEL; + else + prevE = e->PrevInAEL; + } + + if (prevE && prevE->OutIdx >= 0) + { + cInt xPrev = TopX(*prevE, Pt.Y); + cInt xE = TopX(*e, Pt.Y); + if (xPrev == xE && (e->WindDelta != 0) && (prevE->WindDelta != 0) && + SlopesEqual(IntPoint(xPrev, Pt.Y), prevE->Top, IntPoint(xE, Pt.Y), e->Top, m_UseFullRange)) + { + OutPt* outPt = AddOutPt(prevE, Pt); + AddJoin(result, outPt, e->Top); + } + } + return result; +} +//------------------------------------------------------------------------------ + +void Clipper::AddLocalMaxPoly(TEdge *e1, TEdge *e2, const IntPoint &Pt) +{ + AddOutPt( e1, Pt ); + if (e2->WindDelta == 0) AddOutPt(e2, Pt); + if( e1->OutIdx == e2->OutIdx ) + { + e1->OutIdx = Unassigned; + e2->OutIdx = Unassigned; + } + else if (e1->OutIdx < e2->OutIdx) + AppendPolygon(e1, e2); + else + AppendPolygon(e2, e1); +} +//------------------------------------------------------------------------------ + +void Clipper::AddEdgeToSEL(TEdge *edge) +{ + //SEL pointers in PEdge are reused to build a list of horizontal edges. + //However, we don't need to worry about order with horizontal edge processing. + if( !m_SortedEdges ) + { + m_SortedEdges = edge; + edge->PrevInSEL = 0; + edge->NextInSEL = 0; + } + else + { + edge->NextInSEL = m_SortedEdges; + edge->PrevInSEL = 0; + m_SortedEdges->PrevInSEL = edge; + m_SortedEdges = edge; + } +} +//------------------------------------------------------------------------------ + +bool Clipper::PopEdgeFromSEL(TEdge *&edge) +{ + if (!m_SortedEdges) return false; + edge = m_SortedEdges; + DeleteFromSEL(m_SortedEdges); + return true; +} +//------------------------------------------------------------------------------ + +void Clipper::CopyAELToSEL() +{ + TEdge* e = m_ActiveEdges; + m_SortedEdges = e; + while ( e ) + { + e->PrevInSEL = e->PrevInAEL; + e->NextInSEL = e->NextInAEL; + e = e->NextInAEL; + } +} +//------------------------------------------------------------------------------ + +void Clipper::AddJoin(OutPt *op1, OutPt *op2, const IntPoint OffPt) +{ + Join* j = new Join; + j->OutPt1 = op1; + j->OutPt2 = op2; + j->OffPt = OffPt; + m_Joins.push_back(j); +} +//------------------------------------------------------------------------------ + +void Clipper::ClearJoins() +{ + for (JoinList::size_type i = 0; i < m_Joins.size(); i++) + delete m_Joins[i]; + m_Joins.resize(0); +} +//------------------------------------------------------------------------------ + +void Clipper::ClearGhostJoins() +{ + for (JoinList::size_type i = 0; i < m_GhostJoins.size(); i++) + delete m_GhostJoins[i]; + m_GhostJoins.resize(0); +} +//------------------------------------------------------------------------------ + +void Clipper::AddGhostJoin(OutPt *op, const IntPoint OffPt) +{ + Join* j = new Join; + j->OutPt1 = op; + j->OutPt2 = 0; + j->OffPt = OffPt; + m_GhostJoins.push_back(j); +} +//------------------------------------------------------------------------------ + +void Clipper::InsertLocalMinimaIntoAEL(const cInt botY) +{ + const LocalMinimum *lm; + while (PopLocalMinima(botY, lm)) + { + TEdge* lb = lm->LeftBound; + TEdge* rb = lm->RightBound; + + OutPt *Op1 = 0; + if (!lb) + { + //nb: don't insert LB into either AEL or SEL + InsertEdgeIntoAEL(rb, 0); + SetWindingCount(*rb); + if (IsContributing(*rb)) + Op1 = AddOutPt(rb, rb->Bot); + } + else if (!rb) + { + InsertEdgeIntoAEL(lb, 0); + SetWindingCount(*lb); + if (IsContributing(*lb)) + Op1 = AddOutPt(lb, lb->Bot); + InsertScanbeam(lb->Top.Y); + } + else + { + InsertEdgeIntoAEL(lb, 0); + InsertEdgeIntoAEL(rb, lb); + SetWindingCount( *lb ); + rb->WindCnt = lb->WindCnt; + rb->WindCnt2 = lb->WindCnt2; + if (IsContributing(*lb)) + Op1 = AddLocalMinPoly(lb, rb, lb->Bot); + InsertScanbeam(lb->Top.Y); + } + + if (rb) + { + if (IsHorizontal(*rb)) + { + AddEdgeToSEL(rb); + if (rb->NextInLML) + InsertScanbeam(rb->NextInLML->Top.Y); + } + else InsertScanbeam( rb->Top.Y ); + } + + if (!lb || !rb) continue; + + //if any output polygons share an edge, they'll need joining later ... + if (Op1 && IsHorizontal(*rb) && + m_GhostJoins.size() > 0 && (rb->WindDelta != 0)) + { + for (JoinList::size_type i = 0; i < m_GhostJoins.size(); ++i) + { + Join* jr = m_GhostJoins[i]; + //if the horizontal Rb and a 'ghost' horizontal overlap, then convert + //the 'ghost' join to a real join ready for later ... + if (HorzSegmentsOverlap(jr->OutPt1->Pt.X, jr->OffPt.X, rb->Bot.X, rb->Top.X)) + AddJoin(jr->OutPt1, Op1, jr->OffPt); + } + } + + if (lb->OutIdx >= 0 && lb->PrevInAEL && + lb->PrevInAEL->Curr.X == lb->Bot.X && + lb->PrevInAEL->OutIdx >= 0 && + SlopesEqual(lb->PrevInAEL->Bot, lb->PrevInAEL->Top, lb->Curr, lb->Top, m_UseFullRange) && + (lb->WindDelta != 0) && (lb->PrevInAEL->WindDelta != 0)) + { + OutPt *Op2 = AddOutPt(lb->PrevInAEL, lb->Bot); + AddJoin(Op1, Op2, lb->Top); + } + + if(lb->NextInAEL != rb) + { + + if (rb->OutIdx >= 0 && rb->PrevInAEL->OutIdx >= 0 && + SlopesEqual(rb->PrevInAEL->Curr, rb->PrevInAEL->Top, rb->Curr, rb->Top, m_UseFullRange) && + (rb->WindDelta != 0) && (rb->PrevInAEL->WindDelta != 0)) + { + OutPt *Op2 = AddOutPt(rb->PrevInAEL, rb->Bot); + AddJoin(Op1, Op2, rb->Top); + } + + TEdge* e = lb->NextInAEL; + if (e) + { + while( e != rb ) + { + //nb: For calculating winding counts etc, IntersectEdges() assumes + //that param1 will be to the Right of param2 ABOVE the intersection ... + IntersectEdges(rb , e , lb->Curr); //order important here + e = e->NextInAEL; + } + } + } + + } +} +//------------------------------------------------------------------------------ + +void Clipper::DeleteFromSEL(TEdge *e) +{ + TEdge* SelPrev = e->PrevInSEL; + TEdge* SelNext = e->NextInSEL; + if( !SelPrev && !SelNext && (e != m_SortedEdges) ) return; //already deleted + if( SelPrev ) SelPrev->NextInSEL = SelNext; + else m_SortedEdges = SelNext; + if( SelNext ) SelNext->PrevInSEL = SelPrev; + e->NextInSEL = 0; + e->PrevInSEL = 0; +} +//------------------------------------------------------------------------------ + +#ifdef use_xyz +void Clipper::SetZ(IntPoint& pt, TEdge& e1, TEdge& e2) +{ + if (pt.Z != 0 || !m_ZFill) return; + else if (pt == e1.Bot) pt.Z = e1.Bot.Z; + else if (pt == e1.Top) pt.Z = e1.Top.Z; + else if (pt == e2.Bot) pt.Z = e2.Bot.Z; + else if (pt == e2.Top) pt.Z = e2.Top.Z; + else (*m_ZFill)(e1.Bot, e1.Top, e2.Bot, e2.Top, pt); +} +//------------------------------------------------------------------------------ +#endif + +void Clipper::IntersectEdges(TEdge *e1, TEdge *e2, IntPoint &Pt) +{ + bool e1Contributing = ( e1->OutIdx >= 0 ); + bool e2Contributing = ( e2->OutIdx >= 0 ); + +#ifdef use_xyz + SetZ(Pt, *e1, *e2); +#endif + +#ifdef use_lines + //if either edge is on an OPEN path ... + if (e1->WindDelta == 0 || e2->WindDelta == 0) + { + //ignore subject-subject open path intersections UNLESS they + //are both open paths, AND they are both 'contributing maximas' ... + if (e1->WindDelta == 0 && e2->WindDelta == 0) return; + + //if intersecting a subj line with a subj poly ... + else if (e1->PolyTyp == e2->PolyTyp && + e1->WindDelta != e2->WindDelta && m_ClipType == ctUnion) + { + if (e1->WindDelta == 0) + { + if (e2Contributing) + { + AddOutPt(e1, Pt); + if (e1Contributing) e1->OutIdx = Unassigned; + } + } + else + { + if (e1Contributing) + { + AddOutPt(e2, Pt); + if (e2Contributing) e2->OutIdx = Unassigned; + } + } + } + else if (e1->PolyTyp != e2->PolyTyp) + { + //toggle subj open path OutIdx on/off when Abs(clip.WndCnt) == 1 ... + if ((e1->WindDelta == 0) && abs(e2->WindCnt) == 1 && + (m_ClipType != ctUnion || e2->WindCnt2 == 0)) + { + AddOutPt(e1, Pt); + if (e1Contributing) e1->OutIdx = Unassigned; + } + else if ((e2->WindDelta == 0) && (abs(e1->WindCnt) == 1) && + (m_ClipType != ctUnion || e1->WindCnt2 == 0)) + { + AddOutPt(e2, Pt); + if (e2Contributing) e2->OutIdx = Unassigned; + } + } + return; + } +#endif + + //update winding counts... + //assumes that e1 will be to the Right of e2 ABOVE the intersection + if ( e1->PolyTyp == e2->PolyTyp ) + { + if ( IsEvenOddFillType( *e1) ) + { + int oldE1WindCnt = e1->WindCnt; + e1->WindCnt = e2->WindCnt; + e2->WindCnt = oldE1WindCnt; + } else + { + if (e1->WindCnt + e2->WindDelta == 0 ) e1->WindCnt = -e1->WindCnt; + else e1->WindCnt += e2->WindDelta; + if ( e2->WindCnt - e1->WindDelta == 0 ) e2->WindCnt = -e2->WindCnt; + else e2->WindCnt -= e1->WindDelta; + } + } else + { + if (!IsEvenOddFillType(*e2)) e1->WindCnt2 += e2->WindDelta; + else e1->WindCnt2 = ( e1->WindCnt2 == 0 ) ? 1 : 0; + if (!IsEvenOddFillType(*e1)) e2->WindCnt2 -= e1->WindDelta; + else e2->WindCnt2 = ( e2->WindCnt2 == 0 ) ? 1 : 0; + } + + PolyFillType e1FillType, e2FillType, e1FillType2, e2FillType2; + if (e1->PolyTyp == ptSubject) + { + e1FillType = m_SubjFillType; + e1FillType2 = m_ClipFillType; + } else + { + e1FillType = m_ClipFillType; + e1FillType2 = m_SubjFillType; + } + if (e2->PolyTyp == ptSubject) + { + e2FillType = m_SubjFillType; + e2FillType2 = m_ClipFillType; + } else + { + e2FillType = m_ClipFillType; + e2FillType2 = m_SubjFillType; + } + + cInt e1Wc, e2Wc; + switch (e1FillType) + { + case pftPositive: e1Wc = e1->WindCnt; break; + case pftNegative: e1Wc = -e1->WindCnt; break; + default: e1Wc = Abs(e1->WindCnt); + } + switch(e2FillType) + { + case pftPositive: e2Wc = e2->WindCnt; break; + case pftNegative: e2Wc = -e2->WindCnt; break; + default: e2Wc = Abs(e2->WindCnt); + } + + if ( e1Contributing && e2Contributing ) + { + if ((e1Wc != 0 && e1Wc != 1) || (e2Wc != 0 && e2Wc != 1) || + (e1->PolyTyp != e2->PolyTyp && m_ClipType != ctXor) ) + { + AddLocalMaxPoly(e1, e2, Pt); + } + else + { + AddOutPt(e1, Pt); + AddOutPt(e2, Pt); + SwapSides( *e1 , *e2 ); + SwapPolyIndexes( *e1 , *e2 ); + } + } + else if ( e1Contributing ) + { + if (e2Wc == 0 || e2Wc == 1) + { + AddOutPt(e1, Pt); + SwapSides(*e1, *e2); + SwapPolyIndexes(*e1, *e2); + } + } + else if ( e2Contributing ) + { + if (e1Wc == 0 || e1Wc == 1) + { + AddOutPt(e2, Pt); + SwapSides(*e1, *e2); + SwapPolyIndexes(*e1, *e2); + } + } + else if ( (e1Wc == 0 || e1Wc == 1) && (e2Wc == 0 || e2Wc == 1)) + { + //neither edge is currently contributing ... + + cInt e1Wc2, e2Wc2; + switch (e1FillType2) + { + case pftPositive: e1Wc2 = e1->WindCnt2; break; + case pftNegative : e1Wc2 = -e1->WindCnt2; break; + default: e1Wc2 = Abs(e1->WindCnt2); + } + switch (e2FillType2) + { + case pftPositive: e2Wc2 = e2->WindCnt2; break; + case pftNegative: e2Wc2 = -e2->WindCnt2; break; + default: e2Wc2 = Abs(e2->WindCnt2); + } + + if (e1->PolyTyp != e2->PolyTyp) + { + AddLocalMinPoly(e1, e2, Pt); + } + else if (e1Wc == 1 && e2Wc == 1) + switch( m_ClipType ) { + case ctIntersection: + if (e1Wc2 > 0 && e2Wc2 > 0) + AddLocalMinPoly(e1, e2, Pt); + break; + case ctUnion: + if ( e1Wc2 <= 0 && e2Wc2 <= 0 ) + AddLocalMinPoly(e1, e2, Pt); + break; + case ctDifference: + if (((e1->PolyTyp == ptClip) && (e1Wc2 > 0) && (e2Wc2 > 0)) || + ((e1->PolyTyp == ptSubject) && (e1Wc2 <= 0) && (e2Wc2 <= 0))) + AddLocalMinPoly(e1, e2, Pt); + break; + case ctXor: + AddLocalMinPoly(e1, e2, Pt); + } + else + SwapSides( *e1, *e2 ); + } +} +//------------------------------------------------------------------------------ + +void Clipper::SetHoleState(TEdge *e, OutRec *outrec) +{ + TEdge *e2 = e->PrevInAEL; + TEdge *eTmp = 0; + while (e2) + { + if (e2->OutIdx >= 0 && e2->WindDelta != 0) + { + if (!eTmp) eTmp = e2; + else if (eTmp->OutIdx == e2->OutIdx) eTmp = 0; + } + e2 = e2->PrevInAEL; + } + if (!eTmp) + { + outrec->FirstLeft = 0; + outrec->IsHole = false; + } + else + { + outrec->FirstLeft = m_PolyOuts[eTmp->OutIdx]; + outrec->IsHole = !outrec->FirstLeft->IsHole; + } +} +//------------------------------------------------------------------------------ + +OutRec* GetLowermostRec(OutRec *outRec1, OutRec *outRec2) +{ + //work out which polygon fragment has the correct hole state ... + if (!outRec1->BottomPt) + outRec1->BottomPt = GetBottomPt(outRec1->Pts); + if (!outRec2->BottomPt) + outRec2->BottomPt = GetBottomPt(outRec2->Pts); + OutPt *OutPt1 = outRec1->BottomPt; + OutPt *OutPt2 = outRec2->BottomPt; + if (OutPt1->Pt.Y > OutPt2->Pt.Y) return outRec1; + else if (OutPt1->Pt.Y < OutPt2->Pt.Y) return outRec2; + else if (OutPt1->Pt.X < OutPt2->Pt.X) return outRec1; + else if (OutPt1->Pt.X > OutPt2->Pt.X) return outRec2; + else if (OutPt1->Next == OutPt1) return outRec2; + else if (OutPt2->Next == OutPt2) return outRec1; + else if (FirstIsBottomPt(OutPt1, OutPt2)) return outRec1; + else return outRec2; +} +//------------------------------------------------------------------------------ + +bool OutRec1RightOfOutRec2(OutRec* outRec1, OutRec* outRec2) +{ + do + { + outRec1 = outRec1->FirstLeft; + if (outRec1 == outRec2) return true; + } while (outRec1); + return false; +} +//------------------------------------------------------------------------------ + +OutRec* Clipper::GetOutRec(int Idx) +{ + OutRec* outrec = m_PolyOuts[Idx]; + while (outrec != m_PolyOuts[outrec->Idx]) + outrec = m_PolyOuts[outrec->Idx]; + return outrec; +} +//------------------------------------------------------------------------------ + +void Clipper::AppendPolygon(TEdge *e1, TEdge *e2) +{ + //get the start and ends of both output polygons ... + OutRec *outRec1 = m_PolyOuts[e1->OutIdx]; + OutRec *outRec2 = m_PolyOuts[e2->OutIdx]; + + OutRec *holeStateRec; + if (OutRec1RightOfOutRec2(outRec1, outRec2)) + holeStateRec = outRec2; + else if (OutRec1RightOfOutRec2(outRec2, outRec1)) + holeStateRec = outRec1; + else + holeStateRec = GetLowermostRec(outRec1, outRec2); + + //get the start and ends of both output polygons and + //join e2 poly onto e1 poly and delete pointers to e2 ... + + OutPt* p1_lft = outRec1->Pts; + OutPt* p1_rt = p1_lft->Prev; + OutPt* p2_lft = outRec2->Pts; + OutPt* p2_rt = p2_lft->Prev; + + //join e2 poly onto e1 poly and delete pointers to e2 ... + if( e1->Side == esLeft ) + { + if( e2->Side == esLeft ) + { + //z y x a b c + ReversePolyPtLinks(p2_lft); + p2_lft->Next = p1_lft; + p1_lft->Prev = p2_lft; + p1_rt->Next = p2_rt; + p2_rt->Prev = p1_rt; + outRec1->Pts = p2_rt; + } else + { + //x y z a b c + p2_rt->Next = p1_lft; + p1_lft->Prev = p2_rt; + p2_lft->Prev = p1_rt; + p1_rt->Next = p2_lft; + outRec1->Pts = p2_lft; + } + } else + { + if( e2->Side == esRight ) + { + //a b c z y x + ReversePolyPtLinks(p2_lft); + p1_rt->Next = p2_rt; + p2_rt->Prev = p1_rt; + p2_lft->Next = p1_lft; + p1_lft->Prev = p2_lft; + } else + { + //a b c x y z + p1_rt->Next = p2_lft; + p2_lft->Prev = p1_rt; + p1_lft->Prev = p2_rt; + p2_rt->Next = p1_lft; + } + } + + outRec1->BottomPt = 0; + if (holeStateRec == outRec2) + { + if (outRec2->FirstLeft != outRec1) + outRec1->FirstLeft = outRec2->FirstLeft; + outRec1->IsHole = outRec2->IsHole; + } + outRec2->Pts = 0; + outRec2->BottomPt = 0; + outRec2->FirstLeft = outRec1; + + int OKIdx = e1->OutIdx; + int ObsoleteIdx = e2->OutIdx; + + e1->OutIdx = Unassigned; //nb: safe because we only get here via AddLocalMaxPoly + e2->OutIdx = Unassigned; + + TEdge* e = m_ActiveEdges; + while( e ) + { + if( e->OutIdx == ObsoleteIdx ) + { + e->OutIdx = OKIdx; + e->Side = e1->Side; + break; + } + e = e->NextInAEL; + } + + outRec2->Idx = outRec1->Idx; +} +//------------------------------------------------------------------------------ + +OutPt* Clipper::AddOutPt(TEdge *e, const IntPoint &pt) +{ + if( e->OutIdx < 0 ) + { + OutRec *outRec = CreateOutRec(); + outRec->IsOpen = (e->WindDelta == 0); + OutPt* newOp = new OutPt; + outRec->Pts = newOp; + newOp->Idx = outRec->Idx; + newOp->Pt = pt; + newOp->Next = newOp; + newOp->Prev = newOp; + if (!outRec->IsOpen) + SetHoleState(e, outRec); + e->OutIdx = outRec->Idx; + return newOp; + } else + { + OutRec *outRec = m_PolyOuts[e->OutIdx]; + //OutRec.Pts is the 'Left-most' point & OutRec.Pts.Prev is the 'Right-most' + OutPt* op = outRec->Pts; + + bool ToFront = (e->Side == esLeft); + if (ToFront && (pt == op->Pt)) return op; + else if (!ToFront && (pt == op->Prev->Pt)) return op->Prev; + + OutPt* newOp = new OutPt; + newOp->Idx = outRec->Idx; + newOp->Pt = pt; + newOp->Next = op; + newOp->Prev = op->Prev; + newOp->Prev->Next = newOp; + op->Prev = newOp; + if (ToFront) outRec->Pts = newOp; + return newOp; + } +} +//------------------------------------------------------------------------------ + +OutPt* Clipper::GetLastOutPt(TEdge *e) +{ + OutRec *outRec = m_PolyOuts[e->OutIdx]; + if (e->Side == esLeft) + return outRec->Pts; + else + return outRec->Pts->Prev; +} +//------------------------------------------------------------------------------ + +void Clipper::ProcessHorizontals() +{ + TEdge* horzEdge; + while (PopEdgeFromSEL(horzEdge)) + ProcessHorizontal(horzEdge); +} +//------------------------------------------------------------------------------ + +inline bool IsMinima(TEdge *e) +{ + return e && (e->Prev->NextInLML != e) && (e->Next->NextInLML != e); +} +//------------------------------------------------------------------------------ + +inline bool IsMaxima(TEdge *e, const cInt Y) +{ + return e && e->Top.Y == Y && !e->NextInLML; +} +//------------------------------------------------------------------------------ + +inline bool IsIntermediate(TEdge *e, const cInt Y) +{ + return e->Top.Y == Y && e->NextInLML; +} +//------------------------------------------------------------------------------ + +TEdge *GetMaximaPair(TEdge *e) +{ + if ((e->Next->Top == e->Top) && !e->Next->NextInLML) + return e->Next; + else if ((e->Prev->Top == e->Top) && !e->Prev->NextInLML) + return e->Prev; + else return 0; +} +//------------------------------------------------------------------------------ + +TEdge *GetMaximaPairEx(TEdge *e) +{ + //as GetMaximaPair() but returns 0 if MaxPair isn't in AEL (unless it's horizontal) + TEdge* result = GetMaximaPair(e); + if (result && (result->OutIdx == Skip || + (result->NextInAEL == result->PrevInAEL && !IsHorizontal(*result)))) return 0; + return result; +} +//------------------------------------------------------------------------------ + +void Clipper::SwapPositionsInSEL(TEdge *Edge1, TEdge *Edge2) +{ + if( !( Edge1->NextInSEL ) && !( Edge1->PrevInSEL ) ) return; + if( !( Edge2->NextInSEL ) && !( Edge2->PrevInSEL ) ) return; + + if( Edge1->NextInSEL == Edge2 ) + { + TEdge* Next = Edge2->NextInSEL; + if( Next ) Next->PrevInSEL = Edge1; + TEdge* Prev = Edge1->PrevInSEL; + if( Prev ) Prev->NextInSEL = Edge2; + Edge2->PrevInSEL = Prev; + Edge2->NextInSEL = Edge1; + Edge1->PrevInSEL = Edge2; + Edge1->NextInSEL = Next; + } + else if( Edge2->NextInSEL == Edge1 ) + { + TEdge* Next = Edge1->NextInSEL; + if( Next ) Next->PrevInSEL = Edge2; + TEdge* Prev = Edge2->PrevInSEL; + if( Prev ) Prev->NextInSEL = Edge1; + Edge1->PrevInSEL = Prev; + Edge1->NextInSEL = Edge2; + Edge2->PrevInSEL = Edge1; + Edge2->NextInSEL = Next; + } + else + { + TEdge* Next = Edge1->NextInSEL; + TEdge* Prev = Edge1->PrevInSEL; + Edge1->NextInSEL = Edge2->NextInSEL; + if( Edge1->NextInSEL ) Edge1->NextInSEL->PrevInSEL = Edge1; + Edge1->PrevInSEL = Edge2->PrevInSEL; + if( Edge1->PrevInSEL ) Edge1->PrevInSEL->NextInSEL = Edge1; + Edge2->NextInSEL = Next; + if( Edge2->NextInSEL ) Edge2->NextInSEL->PrevInSEL = Edge2; + Edge2->PrevInSEL = Prev; + if( Edge2->PrevInSEL ) Edge2->PrevInSEL->NextInSEL = Edge2; + } + + if( !Edge1->PrevInSEL ) m_SortedEdges = Edge1; + else if( !Edge2->PrevInSEL ) m_SortedEdges = Edge2; +} +//------------------------------------------------------------------------------ + +TEdge* GetNextInAEL(TEdge *e, Direction dir) +{ + return dir == dLeftToRight ? e->NextInAEL : e->PrevInAEL; +} +//------------------------------------------------------------------------------ + +void GetHorzDirection(TEdge& HorzEdge, Direction& Dir, cInt& Left, cInt& Right) +{ + if (HorzEdge.Bot.X < HorzEdge.Top.X) + { + Left = HorzEdge.Bot.X; + Right = HorzEdge.Top.X; + Dir = dLeftToRight; + } else + { + Left = HorzEdge.Top.X; + Right = HorzEdge.Bot.X; + Dir = dRightToLeft; + } +} +//------------------------------------------------------------------------ + +/******************************************************************************* +* Notes: Horizontal edges (HEs) at scanline intersections (ie at the Top or * +* Bottom of a scanbeam) are processed as if layered. The order in which HEs * +* are processed doesn't matter. HEs intersect with other HE Bot.Xs only [#] * +* (or they could intersect with Top.Xs only, ie EITHER Bot.Xs OR Top.Xs), * +* and with other non-horizontal edges [*]. Once these intersections are * +* processed, intermediate HEs then 'promote' the Edge above (NextInLML) into * +* the AEL. These 'promoted' edges may in turn intersect [%] with other HEs. * +*******************************************************************************/ + +void Clipper::ProcessHorizontal(TEdge *horzEdge) +{ + Direction dir; + cInt horzLeft, horzRight; + bool IsOpen = (horzEdge->WindDelta == 0); + + GetHorzDirection(*horzEdge, dir, horzLeft, horzRight); + + TEdge* eLastHorz = horzEdge, *eMaxPair = 0; + while (eLastHorz->NextInLML && IsHorizontal(*eLastHorz->NextInLML)) + eLastHorz = eLastHorz->NextInLML; + if (!eLastHorz->NextInLML) + eMaxPair = GetMaximaPair(eLastHorz); + + MaximaList::const_iterator maxIt; + MaximaList::const_reverse_iterator maxRit; + if (m_Maxima.size() > 0) + { + //get the first maxima in range (X) ... + if (dir == dLeftToRight) + { + maxIt = m_Maxima.begin(); + while (maxIt != m_Maxima.end() && *maxIt <= horzEdge->Bot.X) maxIt++; + if (maxIt != m_Maxima.end() && *maxIt >= eLastHorz->Top.X) + maxIt = m_Maxima.end(); + } + else + { + maxRit = m_Maxima.rbegin(); + while (maxRit != m_Maxima.rend() && *maxRit > horzEdge->Bot.X) maxRit++; + if (maxRit != m_Maxima.rend() && *maxRit <= eLastHorz->Top.X) + maxRit = m_Maxima.rend(); + } + } + + OutPt* op1 = 0; + + for (;;) //loop through consec. horizontal edges + { + + bool IsLastHorz = (horzEdge == eLastHorz); + TEdge* e = GetNextInAEL(horzEdge, dir); + while(e) + { + + //this code block inserts extra coords into horizontal edges (in output + //polygons) whereever maxima touch these horizontal edges. This helps + //'simplifying' polygons (ie if the Simplify property is set). + if (m_Maxima.size() > 0) + { + if (dir == dLeftToRight) + { + while (maxIt != m_Maxima.end() && *maxIt < e->Curr.X) + { + if (horzEdge->OutIdx >= 0 && !IsOpen) + AddOutPt(horzEdge, IntPoint(*maxIt, horzEdge->Bot.Y)); + maxIt++; + } + } + else + { + while (maxRit != m_Maxima.rend() && *maxRit > e->Curr.X) + { + if (horzEdge->OutIdx >= 0 && !IsOpen) + AddOutPt(horzEdge, IntPoint(*maxRit, horzEdge->Bot.Y)); + maxRit++; + } + } + }; + + if ((dir == dLeftToRight && e->Curr.X > horzRight) || + (dir == dRightToLeft && e->Curr.X < horzLeft)) break; + + //Also break if we've got to the end of an intermediate horizontal edge ... + //nb: Smaller Dx's are to the right of larger Dx's ABOVE the horizontal. + if (e->Curr.X == horzEdge->Top.X && horzEdge->NextInLML && + e->Dx < horzEdge->NextInLML->Dx) break; + + if (horzEdge->OutIdx >= 0 && !IsOpen) //note: may be done multiple times + { + op1 = AddOutPt(horzEdge, e->Curr); + TEdge* eNextHorz = m_SortedEdges; + while (eNextHorz) + { + if (eNextHorz->OutIdx >= 0 && + HorzSegmentsOverlap(horzEdge->Bot.X, + horzEdge->Top.X, eNextHorz->Bot.X, eNextHorz->Top.X)) + { + OutPt* op2 = GetLastOutPt(eNextHorz); + AddJoin(op2, op1, eNextHorz->Top); + } + eNextHorz = eNextHorz->NextInSEL; + } + AddGhostJoin(op1, horzEdge->Bot); + } + + //OK, so far we're still in range of the horizontal Edge but make sure + //we're at the last of consec. horizontals when matching with eMaxPair + if(e == eMaxPair && IsLastHorz) + { + if (horzEdge->OutIdx >= 0) + AddLocalMaxPoly(horzEdge, eMaxPair, horzEdge->Top); + DeleteFromAEL(horzEdge); + DeleteFromAEL(eMaxPair); + return; + } + + if(dir == dLeftToRight) + { + IntPoint Pt = IntPoint(e->Curr.X, horzEdge->Curr.Y); + IntersectEdges(horzEdge, e, Pt); + } + else + { + IntPoint Pt = IntPoint(e->Curr.X, horzEdge->Curr.Y); + IntersectEdges( e, horzEdge, Pt); + } + TEdge* eNext = GetNextInAEL(e, dir); + SwapPositionsInAEL( horzEdge, e ); + e = eNext; + } //end while(e) + + //Break out of loop if HorzEdge.NextInLML is not also horizontal ... + if (!horzEdge->NextInLML || !IsHorizontal(*horzEdge->NextInLML)) break; + + UpdateEdgeIntoAEL(horzEdge); + if (horzEdge->OutIdx >= 0) AddOutPt(horzEdge, horzEdge->Bot); + GetHorzDirection(*horzEdge, dir, horzLeft, horzRight); + + } //end for (;;) + + if (horzEdge->OutIdx >= 0 && !op1) + { + op1 = GetLastOutPt(horzEdge); + TEdge* eNextHorz = m_SortedEdges; + while (eNextHorz) + { + if (eNextHorz->OutIdx >= 0 && + HorzSegmentsOverlap(horzEdge->Bot.X, + horzEdge->Top.X, eNextHorz->Bot.X, eNextHorz->Top.X)) + { + OutPt* op2 = GetLastOutPt(eNextHorz); + AddJoin(op2, op1, eNextHorz->Top); + } + eNextHorz = eNextHorz->NextInSEL; + } + AddGhostJoin(op1, horzEdge->Top); + } + + if (horzEdge->NextInLML) + { + if(horzEdge->OutIdx >= 0) + { + op1 = AddOutPt( horzEdge, horzEdge->Top); + UpdateEdgeIntoAEL(horzEdge); + if (horzEdge->WindDelta == 0) return; + //nb: HorzEdge is no longer horizontal here + TEdge* ePrev = horzEdge->PrevInAEL; + TEdge* eNext = horzEdge->NextInAEL; + if (ePrev && ePrev->Curr.X == horzEdge->Bot.X && + ePrev->Curr.Y == horzEdge->Bot.Y && ePrev->WindDelta != 0 && + (ePrev->OutIdx >= 0 && ePrev->Curr.Y > ePrev->Top.Y && + SlopesEqual(*horzEdge, *ePrev, m_UseFullRange))) + { + OutPt* op2 = AddOutPt(ePrev, horzEdge->Bot); + AddJoin(op1, op2, horzEdge->Top); + } + else if (eNext && eNext->Curr.X == horzEdge->Bot.X && + eNext->Curr.Y == horzEdge->Bot.Y && eNext->WindDelta != 0 && + eNext->OutIdx >= 0 && eNext->Curr.Y > eNext->Top.Y && + SlopesEqual(*horzEdge, *eNext, m_UseFullRange)) + { + OutPt* op2 = AddOutPt(eNext, horzEdge->Bot); + AddJoin(op1, op2, horzEdge->Top); + } + } + else + UpdateEdgeIntoAEL(horzEdge); + } + else + { + if (horzEdge->OutIdx >= 0) AddOutPt(horzEdge, horzEdge->Top); + DeleteFromAEL(horzEdge); + } +} +//------------------------------------------------------------------------------ + +bool Clipper::ProcessIntersections(const cInt topY) +{ + if( !m_ActiveEdges ) return true; + try { + BuildIntersectList(topY); + size_t IlSize = m_IntersectList.size(); + if (IlSize == 0) return true; + if (IlSize == 1 || FixupIntersectionOrder()) ProcessIntersectList(); + else return false; + } + catch(...) + { + m_SortedEdges = 0; + DisposeIntersectNodes(); + throw clipperException("ProcessIntersections error"); + } + m_SortedEdges = 0; + return true; +} +//------------------------------------------------------------------------------ + +void Clipper::DisposeIntersectNodes() +{ + for (size_t i = 0; i < m_IntersectList.size(); ++i ) + delete m_IntersectList[i]; + m_IntersectList.clear(); +} +//------------------------------------------------------------------------------ + +void Clipper::BuildIntersectList(const cInt topY) +{ + if ( !m_ActiveEdges ) return; + + //prepare for sorting ... + TEdge* e = m_ActiveEdges; + m_SortedEdges = e; + while( e ) + { + e->PrevInSEL = e->PrevInAEL; + e->NextInSEL = e->NextInAEL; + e->Curr.X = TopX( *e, topY ); + e = e->NextInAEL; + } + + //bubblesort ... + bool isModified; + do + { + isModified = false; + e = m_SortedEdges; + while( e->NextInSEL ) + { + TEdge *eNext = e->NextInSEL; + IntPoint Pt; + if(e->Curr.X > eNext->Curr.X) + { + IntersectPoint(*e, *eNext, Pt); + if (Pt.Y < topY) Pt = IntPoint(TopX(*e, topY), topY); + IntersectNode * newNode = new IntersectNode; + newNode->Edge1 = e; + newNode->Edge2 = eNext; + newNode->Pt = Pt; + m_IntersectList.push_back(newNode); + + SwapPositionsInSEL(e, eNext); + isModified = true; + } + else + e = eNext; + } + if( e->PrevInSEL ) e->PrevInSEL->NextInSEL = 0; + else break; + } + while ( isModified ); + m_SortedEdges = 0; //important +} +//------------------------------------------------------------------------------ + + +void Clipper::ProcessIntersectList() +{ + for (size_t i = 0; i < m_IntersectList.size(); ++i) + { + IntersectNode* iNode = m_IntersectList[i]; + { + IntersectEdges( iNode->Edge1, iNode->Edge2, iNode->Pt); + SwapPositionsInAEL( iNode->Edge1 , iNode->Edge2 ); + } + delete iNode; + } + m_IntersectList.clear(); +} +//------------------------------------------------------------------------------ + +bool IntersectListSort(IntersectNode* node1, IntersectNode* node2) +{ + return node2->Pt.Y < node1->Pt.Y; +} +//------------------------------------------------------------------------------ + +inline bool EdgesAdjacent(const IntersectNode &inode) +{ + return (inode.Edge1->NextInSEL == inode.Edge2) || + (inode.Edge1->PrevInSEL == inode.Edge2); +} +//------------------------------------------------------------------------------ + +bool Clipper::FixupIntersectionOrder() +{ + //pre-condition: intersections are sorted Bottom-most first. + //Now it's crucial that intersections are made only between adjacent edges, + //so to ensure this the order of intersections may need adjusting ... + CopyAELToSEL(); + std::sort(m_IntersectList.begin(), m_IntersectList.end(), IntersectListSort); + size_t cnt = m_IntersectList.size(); + for (size_t i = 0; i < cnt; ++i) + { + if (!EdgesAdjacent(*m_IntersectList[i])) + { + size_t j = i + 1; + while (j < cnt && !EdgesAdjacent(*m_IntersectList[j])) j++; + if (j == cnt) return false; + std::swap(m_IntersectList[i], m_IntersectList[j]); + } + SwapPositionsInSEL(m_IntersectList[i]->Edge1, m_IntersectList[i]->Edge2); + } + return true; +} +//------------------------------------------------------------------------------ + +void Clipper::DoMaxima(TEdge *e) +{ + TEdge* eMaxPair = GetMaximaPairEx(e); + if (!eMaxPair) + { + if (e->OutIdx >= 0) + AddOutPt(e, e->Top); + DeleteFromAEL(e); + return; + } + + TEdge* eNext = e->NextInAEL; + while(eNext && eNext != eMaxPair) + { + IntersectEdges(e, eNext, e->Top); + SwapPositionsInAEL(e, eNext); + eNext = e->NextInAEL; + } + + if(e->OutIdx == Unassigned && eMaxPair->OutIdx == Unassigned) + { + DeleteFromAEL(e); + DeleteFromAEL(eMaxPair); + } + else if( e->OutIdx >= 0 && eMaxPair->OutIdx >= 0 ) + { + if (e->OutIdx >= 0) AddLocalMaxPoly(e, eMaxPair, e->Top); + DeleteFromAEL(e); + DeleteFromAEL(eMaxPair); + } +#ifdef use_lines + else if (e->WindDelta == 0) + { + if (e->OutIdx >= 0) + { + AddOutPt(e, e->Top); + e->OutIdx = Unassigned; + } + DeleteFromAEL(e); + + if (eMaxPair->OutIdx >= 0) + { + AddOutPt(eMaxPair, e->Top); + eMaxPair->OutIdx = Unassigned; + } + DeleteFromAEL(eMaxPair); + } +#endif + else throw clipperException("DoMaxima error"); +} +//------------------------------------------------------------------------------ + +void Clipper::ProcessEdgesAtTopOfScanbeam(const cInt topY) +{ + TEdge* e = m_ActiveEdges; + while( e ) + { + //1. process maxima, treating them as if they're 'bent' horizontal edges, + // but exclude maxima with horizontal edges. nb: e can't be a horizontal. + bool IsMaximaEdge = IsMaxima(e, topY); + + if(IsMaximaEdge) + { + TEdge* eMaxPair = GetMaximaPairEx(e); + IsMaximaEdge = (!eMaxPair || !IsHorizontal(*eMaxPair)); + } + + if(IsMaximaEdge) + { + if (m_StrictSimple) m_Maxima.push_back(e->Top.X); + TEdge* ePrev = e->PrevInAEL; + DoMaxima(e); + if( !ePrev ) e = m_ActiveEdges; + else e = ePrev->NextInAEL; + } + else + { + //2. promote horizontal edges, otherwise update Curr.X and Curr.Y ... + if (IsIntermediate(e, topY) && IsHorizontal(*e->NextInLML)) + { + UpdateEdgeIntoAEL(e); + if (e->OutIdx >= 0) + AddOutPt(e, e->Bot); + AddEdgeToSEL(e); + } + else + { + e->Curr.X = TopX( *e, topY ); + e->Curr.Y = topY; + } + + //When StrictlySimple and 'e' is being touched by another edge, then + //make sure both edges have a vertex here ... + if (m_StrictSimple) + { + TEdge* ePrev = e->PrevInAEL; + if ((e->OutIdx >= 0) && (e->WindDelta != 0) && ePrev && (ePrev->OutIdx >= 0) && + (ePrev->Curr.X == e->Curr.X) && (ePrev->WindDelta != 0)) + { + IntPoint pt = e->Curr; +#ifdef use_xyz + SetZ(pt, *ePrev, *e); +#endif + OutPt* op = AddOutPt(ePrev, pt); + OutPt* op2 = AddOutPt(e, pt); + AddJoin(op, op2, pt); //StrictlySimple (type-3) join + } + } + + e = e->NextInAEL; + } + } + + //3. Process horizontals at the Top of the scanbeam ... + m_Maxima.sort(); + ProcessHorizontals(); + m_Maxima.clear(); + + //4. Promote intermediate vertices ... + e = m_ActiveEdges; + while(e) + { + if(IsIntermediate(e, topY)) + { + OutPt* op = 0; + if( e->OutIdx >= 0 ) + op = AddOutPt(e, e->Top); + UpdateEdgeIntoAEL(e); + + //if output polygons share an edge, they'll need joining later ... + TEdge* ePrev = e->PrevInAEL; + TEdge* eNext = e->NextInAEL; + if (ePrev && ePrev->Curr.X == e->Bot.X && + ePrev->Curr.Y == e->Bot.Y && op && + ePrev->OutIdx >= 0 && ePrev->Curr.Y > ePrev->Top.Y && + SlopesEqual(e->Curr, e->Top, ePrev->Curr, ePrev->Top, m_UseFullRange) && + (e->WindDelta != 0) && (ePrev->WindDelta != 0)) + { + OutPt* op2 = AddOutPt(ePrev, e->Bot); + AddJoin(op, op2, e->Top); + } + else if (eNext && eNext->Curr.X == e->Bot.X && + eNext->Curr.Y == e->Bot.Y && op && + eNext->OutIdx >= 0 && eNext->Curr.Y > eNext->Top.Y && + SlopesEqual(e->Curr, e->Top, eNext->Curr, eNext->Top, m_UseFullRange) && + (e->WindDelta != 0) && (eNext->WindDelta != 0)) + { + OutPt* op2 = AddOutPt(eNext, e->Bot); + AddJoin(op, op2, e->Top); + } + } + e = e->NextInAEL; + } +} +//------------------------------------------------------------------------------ + +void Clipper::FixupOutPolyline(OutRec &outrec) +{ + OutPt *pp = outrec.Pts; + OutPt *lastPP = pp->Prev; + while (pp != lastPP) + { + pp = pp->Next; + if (pp->Pt == pp->Prev->Pt) + { + if (pp == lastPP) lastPP = pp->Prev; + OutPt *tmpPP = pp->Prev; + tmpPP->Next = pp->Next; + pp->Next->Prev = tmpPP; + delete pp; + pp = tmpPP; + } + } + + if (pp == pp->Prev) + { + DisposeOutPts(pp); + outrec.Pts = 0; + return; + } +} +//------------------------------------------------------------------------------ + +void Clipper::FixupOutPolygon(OutRec &outrec) +{ + //FixupOutPolygon() - removes duplicate points and simplifies consecutive + //parallel edges by removing the middle vertex. + OutPt *lastOK = 0; + outrec.BottomPt = 0; + OutPt *pp = outrec.Pts; + bool preserveCol = m_PreserveCollinear || m_StrictSimple; + + for (;;) + { + if (pp->Prev == pp || pp->Prev == pp->Next) + { + DisposeOutPts(pp); + outrec.Pts = 0; + return; + } + + //test for duplicate points and collinear edges ... + if ((pp->Pt == pp->Next->Pt) || (pp->Pt == pp->Prev->Pt) || + (SlopesEqual(pp->Prev->Pt, pp->Pt, pp->Next->Pt, m_UseFullRange) && + (!preserveCol || !Pt2IsBetweenPt1AndPt3(pp->Prev->Pt, pp->Pt, pp->Next->Pt)))) + { + lastOK = 0; + OutPt *tmp = pp; + pp->Prev->Next = pp->Next; + pp->Next->Prev = pp->Prev; + pp = pp->Prev; + delete tmp; + } + else if (pp == lastOK) break; + else + { + if (!lastOK) lastOK = pp; + pp = pp->Next; + } + } + outrec.Pts = pp; +} +//------------------------------------------------------------------------------ + +int PointCount(OutPt *Pts) +{ + if (!Pts) return 0; + int result = 0; + OutPt* p = Pts; + do + { + result++; + p = p->Next; + } + while (p != Pts); + return result; +} +//------------------------------------------------------------------------------ + +void Clipper::BuildResult(Paths &polys) +{ + polys.reserve(m_PolyOuts.size()); + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + { + if (!m_PolyOuts[i]->Pts) continue; + Path pg; + OutPt* p = m_PolyOuts[i]->Pts->Prev; + int cnt = PointCount(p); + if (cnt < 2) continue; + pg.reserve(cnt); + for (int i = 0; i < cnt; ++i) + { + pg.push_back(p->Pt); + p = p->Prev; + } + polys.push_back(pg); + } +} +//------------------------------------------------------------------------------ + +void Clipper::BuildResult2(PolyTree& polytree) +{ + polytree.Clear(); + polytree.AllNodes.reserve(m_PolyOuts.size()); + //add each output polygon/contour to polytree ... + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); i++) + { + OutRec* outRec = m_PolyOuts[i]; + int cnt = PointCount(outRec->Pts); + if ((outRec->IsOpen && cnt < 2) || (!outRec->IsOpen && cnt < 3)) continue; + FixHoleLinkage(*outRec); + PolyNode* pn = new PolyNode(); + //nb: polytree takes ownership of all the PolyNodes + polytree.AllNodes.push_back(pn); + outRec->PolyNd = pn; + pn->Parent = 0; + pn->Index = 0; + pn->Contour.reserve(cnt); + OutPt *op = outRec->Pts->Prev; + for (int j = 0; j < cnt; j++) + { + pn->Contour.push_back(op->Pt); + op = op->Prev; + } + } + + //fixup PolyNode links etc ... + polytree.Childs.reserve(m_PolyOuts.size()); + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); i++) + { + OutRec* outRec = m_PolyOuts[i]; + if (!outRec->PolyNd) continue; + if (outRec->IsOpen) + { + outRec->PolyNd->m_IsOpen = true; + polytree.AddChild(*outRec->PolyNd); + } + else if (outRec->FirstLeft && outRec->FirstLeft->PolyNd) + outRec->FirstLeft->PolyNd->AddChild(*outRec->PolyNd); + else + polytree.AddChild(*outRec->PolyNd); + } +} +//------------------------------------------------------------------------------ + +void SwapIntersectNodes(IntersectNode &int1, IntersectNode &int2) +{ + //just swap the contents (because fIntersectNodes is a single-linked-list) + IntersectNode inode = int1; //gets a copy of Int1 + int1.Edge1 = int2.Edge1; + int1.Edge2 = int2.Edge2; + int1.Pt = int2.Pt; + int2.Edge1 = inode.Edge1; + int2.Edge2 = inode.Edge2; + int2.Pt = inode.Pt; +} +//------------------------------------------------------------------------------ + +inline bool E2InsertsBeforeE1(TEdge &e1, TEdge &e2) +{ + if (e2.Curr.X == e1.Curr.X) + { + if (e2.Top.Y > e1.Top.Y) + return e2.Top.X < TopX(e1, e2.Top.Y); + else return e1.Top.X > TopX(e2, e1.Top.Y); + } + else return e2.Curr.X < e1.Curr.X; +} +//------------------------------------------------------------------------------ + +bool GetOverlap(const cInt a1, const cInt a2, const cInt b1, const cInt b2, + cInt& Left, cInt& Right) +{ + if (a1 < a2) + { + if (b1 < b2) {Left = std::max(a1,b1); Right = std::min(a2,b2);} + else {Left = std::max(a1,b2); Right = std::min(a2,b1);} + } + else + { + if (b1 < b2) {Left = std::max(a2,b1); Right = std::min(a1,b2);} + else {Left = std::max(a2,b2); Right = std::min(a1,b1);} + } + return Left < Right; +} +//------------------------------------------------------------------------------ + +inline void UpdateOutPtIdxs(OutRec& outrec) +{ + OutPt* op = outrec.Pts; + do + { + op->Idx = outrec.Idx; + op = op->Prev; + } + while(op != outrec.Pts); +} +//------------------------------------------------------------------------------ + +void Clipper::InsertEdgeIntoAEL(TEdge *edge, TEdge* startEdge) +{ + if(!m_ActiveEdges) + { + edge->PrevInAEL = 0; + edge->NextInAEL = 0; + m_ActiveEdges = edge; + } + else if(!startEdge && E2InsertsBeforeE1(*m_ActiveEdges, *edge)) + { + edge->PrevInAEL = 0; + edge->NextInAEL = m_ActiveEdges; + m_ActiveEdges->PrevInAEL = edge; + m_ActiveEdges = edge; + } + else + { + if(!startEdge) startEdge = m_ActiveEdges; + while(startEdge->NextInAEL && + !E2InsertsBeforeE1(*startEdge->NextInAEL , *edge)) + startEdge = startEdge->NextInAEL; + edge->NextInAEL = startEdge->NextInAEL; + if(startEdge->NextInAEL) startEdge->NextInAEL->PrevInAEL = edge; + edge->PrevInAEL = startEdge; + startEdge->NextInAEL = edge; + } +} +//---------------------------------------------------------------------- + +OutPt* DupOutPt(OutPt* outPt, bool InsertAfter) +{ + OutPt* result = new OutPt; + result->Pt = outPt->Pt; + result->Idx = outPt->Idx; + if (InsertAfter) + { + result->Next = outPt->Next; + result->Prev = outPt; + outPt->Next->Prev = result; + outPt->Next = result; + } + else + { + result->Prev = outPt->Prev; + result->Next = outPt; + outPt->Prev->Next = result; + outPt->Prev = result; + } + return result; +} +//------------------------------------------------------------------------------ + +bool JoinHorz(OutPt* op1, OutPt* op1b, OutPt* op2, OutPt* op2b, + const IntPoint Pt, bool DiscardLeft) +{ + Direction Dir1 = (op1->Pt.X > op1b->Pt.X ? dRightToLeft : dLeftToRight); + Direction Dir2 = (op2->Pt.X > op2b->Pt.X ? dRightToLeft : dLeftToRight); + if (Dir1 == Dir2) return false; + + //When DiscardLeft, we want Op1b to be on the Left of Op1, otherwise we + //want Op1b to be on the Right. (And likewise with Op2 and Op2b.) + //So, to facilitate this while inserting Op1b and Op2b ... + //when DiscardLeft, make sure we're AT or RIGHT of Pt before adding Op1b, + //otherwise make sure we're AT or LEFT of Pt. (Likewise with Op2b.) + if (Dir1 == dLeftToRight) + { + while (op1->Next->Pt.X <= Pt.X && + op1->Next->Pt.X >= op1->Pt.X && op1->Next->Pt.Y == Pt.Y) + op1 = op1->Next; + if (DiscardLeft && (op1->Pt.X != Pt.X)) op1 = op1->Next; + op1b = DupOutPt(op1, !DiscardLeft); + if (op1b->Pt != Pt) + { + op1 = op1b; + op1->Pt = Pt; + op1b = DupOutPt(op1, !DiscardLeft); + } + } + else + { + while (op1->Next->Pt.X >= Pt.X && + op1->Next->Pt.X <= op1->Pt.X && op1->Next->Pt.Y == Pt.Y) + op1 = op1->Next; + if (!DiscardLeft && (op1->Pt.X != Pt.X)) op1 = op1->Next; + op1b = DupOutPt(op1, DiscardLeft); + if (op1b->Pt != Pt) + { + op1 = op1b; + op1->Pt = Pt; + op1b = DupOutPt(op1, DiscardLeft); + } + } + + if (Dir2 == dLeftToRight) + { + while (op2->Next->Pt.X <= Pt.X && + op2->Next->Pt.X >= op2->Pt.X && op2->Next->Pt.Y == Pt.Y) + op2 = op2->Next; + if (DiscardLeft && (op2->Pt.X != Pt.X)) op2 = op2->Next; + op2b = DupOutPt(op2, !DiscardLeft); + if (op2b->Pt != Pt) + { + op2 = op2b; + op2->Pt = Pt; + op2b = DupOutPt(op2, !DiscardLeft); + }; + } else + { + while (op2->Next->Pt.X >= Pt.X && + op2->Next->Pt.X <= op2->Pt.X && op2->Next->Pt.Y == Pt.Y) + op2 = op2->Next; + if (!DiscardLeft && (op2->Pt.X != Pt.X)) op2 = op2->Next; + op2b = DupOutPt(op2, DiscardLeft); + if (op2b->Pt != Pt) + { + op2 = op2b; + op2->Pt = Pt; + op2b = DupOutPt(op2, DiscardLeft); + }; + }; + + if ((Dir1 == dLeftToRight) == DiscardLeft) + { + op1->Prev = op2; + op2->Next = op1; + op1b->Next = op2b; + op2b->Prev = op1b; + } + else + { + op1->Next = op2; + op2->Prev = op1; + op1b->Prev = op2b; + op2b->Next = op1b; + } + return true; +} +//------------------------------------------------------------------------------ + +bool Clipper::JoinPoints(Join *j, OutRec* outRec1, OutRec* outRec2) +{ + OutPt *op1 = j->OutPt1, *op1b; + OutPt *op2 = j->OutPt2, *op2b; + + //There are 3 kinds of joins for output polygons ... + //1. Horizontal joins where Join.OutPt1 & Join.OutPt2 are vertices anywhere + //along (horizontal) collinear edges (& Join.OffPt is on the same horizontal). + //2. Non-horizontal joins where Join.OutPt1 & Join.OutPt2 are at the same + //location at the Bottom of the overlapping segment (& Join.OffPt is above). + //3. StrictSimple joins where edges touch but are not collinear and where + //Join.OutPt1, Join.OutPt2 & Join.OffPt all share the same point. + bool isHorizontal = (j->OutPt1->Pt.Y == j->OffPt.Y); + + if (isHorizontal && (j->OffPt == j->OutPt1->Pt) && + (j->OffPt == j->OutPt2->Pt)) + { + //Strictly Simple join ... + if (outRec1 != outRec2) return false; + op1b = j->OutPt1->Next; + while (op1b != op1 && (op1b->Pt == j->OffPt)) + op1b = op1b->Next; + bool reverse1 = (op1b->Pt.Y > j->OffPt.Y); + op2b = j->OutPt2->Next; + while (op2b != op2 && (op2b->Pt == j->OffPt)) + op2b = op2b->Next; + bool reverse2 = (op2b->Pt.Y > j->OffPt.Y); + if (reverse1 == reverse2) return false; + if (reverse1) + { + op1b = DupOutPt(op1, false); + op2b = DupOutPt(op2, true); + op1->Prev = op2; + op2->Next = op1; + op1b->Next = op2b; + op2b->Prev = op1b; + j->OutPt1 = op1; + j->OutPt2 = op1b; + return true; + } else + { + op1b = DupOutPt(op1, true); + op2b = DupOutPt(op2, false); + op1->Next = op2; + op2->Prev = op1; + op1b->Prev = op2b; + op2b->Next = op1b; + j->OutPt1 = op1; + j->OutPt2 = op1b; + return true; + } + } + else if (isHorizontal) + { + //treat horizontal joins differently to non-horizontal joins since with + //them we're not yet sure where the overlapping is. OutPt1.Pt & OutPt2.Pt + //may be anywhere along the horizontal edge. + op1b = op1; + while (op1->Prev->Pt.Y == op1->Pt.Y && op1->Prev != op1b && op1->Prev != op2) + op1 = op1->Prev; + while (op1b->Next->Pt.Y == op1b->Pt.Y && op1b->Next != op1 && op1b->Next != op2) + op1b = op1b->Next; + if (op1b->Next == op1 || op1b->Next == op2) return false; //a flat 'polygon' + + op2b = op2; + while (op2->Prev->Pt.Y == op2->Pt.Y && op2->Prev != op2b && op2->Prev != op1b) + op2 = op2->Prev; + while (op2b->Next->Pt.Y == op2b->Pt.Y && op2b->Next != op2 && op2b->Next != op1) + op2b = op2b->Next; + if (op2b->Next == op2 || op2b->Next == op1) return false; //a flat 'polygon' + + cInt Left, Right; + //Op1 --> Op1b & Op2 --> Op2b are the extremites of the horizontal edges + if (!GetOverlap(op1->Pt.X, op1b->Pt.X, op2->Pt.X, op2b->Pt.X, Left, Right)) + return false; + + //DiscardLeftSide: when overlapping edges are joined, a spike will created + //which needs to be cleaned up. However, we don't want Op1 or Op2 caught up + //on the discard Side as either may still be needed for other joins ... + IntPoint Pt; + bool DiscardLeftSide; + if (op1->Pt.X >= Left && op1->Pt.X <= Right) + { + Pt = op1->Pt; DiscardLeftSide = (op1->Pt.X > op1b->Pt.X); + } + else if (op2->Pt.X >= Left&& op2->Pt.X <= Right) + { + Pt = op2->Pt; DiscardLeftSide = (op2->Pt.X > op2b->Pt.X); + } + else if (op1b->Pt.X >= Left && op1b->Pt.X <= Right) + { + Pt = op1b->Pt; DiscardLeftSide = op1b->Pt.X > op1->Pt.X; + } + else + { + Pt = op2b->Pt; DiscardLeftSide = (op2b->Pt.X > op2->Pt.X); + } + j->OutPt1 = op1; j->OutPt2 = op2; + return JoinHorz(op1, op1b, op2, op2b, Pt, DiscardLeftSide); + } else + { + //nb: For non-horizontal joins ... + // 1. Jr.OutPt1.Pt.Y == Jr.OutPt2.Pt.Y + // 2. Jr.OutPt1.Pt > Jr.OffPt.Y + + //make sure the polygons are correctly oriented ... + op1b = op1->Next; + while ((op1b->Pt == op1->Pt) && (op1b != op1)) op1b = op1b->Next; + bool Reverse1 = ((op1b->Pt.Y > op1->Pt.Y) || + !SlopesEqual(op1->Pt, op1b->Pt, j->OffPt, m_UseFullRange)); + if (Reverse1) + { + op1b = op1->Prev; + while ((op1b->Pt == op1->Pt) && (op1b != op1)) op1b = op1b->Prev; + if ((op1b->Pt.Y > op1->Pt.Y) || + !SlopesEqual(op1->Pt, op1b->Pt, j->OffPt, m_UseFullRange)) return false; + }; + op2b = op2->Next; + while ((op2b->Pt == op2->Pt) && (op2b != op2))op2b = op2b->Next; + bool Reverse2 = ((op2b->Pt.Y > op2->Pt.Y) || + !SlopesEqual(op2->Pt, op2b->Pt, j->OffPt, m_UseFullRange)); + if (Reverse2) + { + op2b = op2->Prev; + while ((op2b->Pt == op2->Pt) && (op2b != op2)) op2b = op2b->Prev; + if ((op2b->Pt.Y > op2->Pt.Y) || + !SlopesEqual(op2->Pt, op2b->Pt, j->OffPt, m_UseFullRange)) return false; + } + + if ((op1b == op1) || (op2b == op2) || (op1b == op2b) || + ((outRec1 == outRec2) && (Reverse1 == Reverse2))) return false; + + if (Reverse1) + { + op1b = DupOutPt(op1, false); + op2b = DupOutPt(op2, true); + op1->Prev = op2; + op2->Next = op1; + op1b->Next = op2b; + op2b->Prev = op1b; + j->OutPt1 = op1; + j->OutPt2 = op1b; + return true; + } else + { + op1b = DupOutPt(op1, true); + op2b = DupOutPt(op2, false); + op1->Next = op2; + op2->Prev = op1; + op1b->Prev = op2b; + op2b->Next = op1b; + j->OutPt1 = op1; + j->OutPt2 = op1b; + return true; + } + } +} +//---------------------------------------------------------------------- + +static OutRec* ParseFirstLeft(OutRec* FirstLeft) +{ + while (FirstLeft && !FirstLeft->Pts) + FirstLeft = FirstLeft->FirstLeft; + return FirstLeft; +} +//------------------------------------------------------------------------------ + +void Clipper::FixupFirstLefts1(OutRec* OldOutRec, OutRec* NewOutRec) +{ + //tests if NewOutRec contains the polygon before reassigning FirstLeft + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + { + OutRec* outRec = m_PolyOuts[i]; + OutRec* firstLeft = ParseFirstLeft(outRec->FirstLeft); + if (outRec->Pts && firstLeft == OldOutRec) + { + if (Poly2ContainsPoly1(outRec->Pts, NewOutRec->Pts)) + outRec->FirstLeft = NewOutRec; + } + } +} +//---------------------------------------------------------------------- + +void Clipper::FixupFirstLefts2(OutRec* InnerOutRec, OutRec* OuterOutRec) +{ + //A polygon has split into two such that one is now the inner of the other. + //It's possible that these polygons now wrap around other polygons, so check + //every polygon that's also contained by OuterOutRec's FirstLeft container + //(including 0) to see if they've become inner to the new inner polygon ... + OutRec* orfl = OuterOutRec->FirstLeft; + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + { + OutRec* outRec = m_PolyOuts[i]; + + if (!outRec->Pts || outRec == OuterOutRec || outRec == InnerOutRec) + continue; + OutRec* firstLeft = ParseFirstLeft(outRec->FirstLeft); + if (firstLeft != orfl && firstLeft != InnerOutRec && firstLeft != OuterOutRec) + continue; + if (Poly2ContainsPoly1(outRec->Pts, InnerOutRec->Pts)) + outRec->FirstLeft = InnerOutRec; + else if (Poly2ContainsPoly1(outRec->Pts, OuterOutRec->Pts)) + outRec->FirstLeft = OuterOutRec; + else if (outRec->FirstLeft == InnerOutRec || outRec->FirstLeft == OuterOutRec) + outRec->FirstLeft = orfl; + } +} +//---------------------------------------------------------------------- +void Clipper::FixupFirstLefts3(OutRec* OldOutRec, OutRec* NewOutRec) +{ + //reassigns FirstLeft WITHOUT testing if NewOutRec contains the polygon + for (PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i) + { + OutRec* outRec = m_PolyOuts[i]; + OutRec* firstLeft = ParseFirstLeft(outRec->FirstLeft); + if (outRec->Pts && outRec->FirstLeft == OldOutRec) + outRec->FirstLeft = NewOutRec; + } +} +//---------------------------------------------------------------------- + +void Clipper::JoinCommonEdges() +{ + for (JoinList::size_type i = 0; i < m_Joins.size(); i++) + { + Join* join = m_Joins[i]; + + OutRec *outRec1 = GetOutRec(join->OutPt1->Idx); + OutRec *outRec2 = GetOutRec(join->OutPt2->Idx); + + if (!outRec1->Pts || !outRec2->Pts) continue; + if (outRec1->IsOpen || outRec2->IsOpen) continue; + + //get the polygon fragment with the correct hole state (FirstLeft) + //before calling JoinPoints() ... + OutRec *holeStateRec; + if (outRec1 == outRec2) holeStateRec = outRec1; + else if (OutRec1RightOfOutRec2(outRec1, outRec2)) holeStateRec = outRec2; + else if (OutRec1RightOfOutRec2(outRec2, outRec1)) holeStateRec = outRec1; + else holeStateRec = GetLowermostRec(outRec1, outRec2); + + if (!JoinPoints(join, outRec1, outRec2)) continue; + + if (outRec1 == outRec2) + { + //instead of joining two polygons, we've just created a new one by + //splitting one polygon into two. + outRec1->Pts = join->OutPt1; + outRec1->BottomPt = 0; + outRec2 = CreateOutRec(); + outRec2->Pts = join->OutPt2; + + //update all OutRec2.Pts Idx's ... + UpdateOutPtIdxs(*outRec2); + + if (Poly2ContainsPoly1(outRec2->Pts, outRec1->Pts)) + { + //outRec1 contains outRec2 ... + outRec2->IsHole = !outRec1->IsHole; + outRec2->FirstLeft = outRec1; + + if (m_UsingPolyTree) FixupFirstLefts2(outRec2, outRec1); + + if ((outRec2->IsHole ^ m_ReverseOutput) == (Area(*outRec2) > 0)) + ReversePolyPtLinks(outRec2->Pts); + + } else if (Poly2ContainsPoly1(outRec1->Pts, outRec2->Pts)) + { + //outRec2 contains outRec1 ... + outRec2->IsHole = outRec1->IsHole; + outRec1->IsHole = !outRec2->IsHole; + outRec2->FirstLeft = outRec1->FirstLeft; + outRec1->FirstLeft = outRec2; + + if (m_UsingPolyTree) FixupFirstLefts2(outRec1, outRec2); + + if ((outRec1->IsHole ^ m_ReverseOutput) == (Area(*outRec1) > 0)) + ReversePolyPtLinks(outRec1->Pts); + } + else + { + //the 2 polygons are completely separate ... + outRec2->IsHole = outRec1->IsHole; + outRec2->FirstLeft = outRec1->FirstLeft; + + //fixup FirstLeft pointers that may need reassigning to OutRec2 + if (m_UsingPolyTree) FixupFirstLefts1(outRec1, outRec2); + } + + } else + { + //joined 2 polygons together ... + + outRec2->Pts = 0; + outRec2->BottomPt = 0; + outRec2->Idx = outRec1->Idx; + + outRec1->IsHole = holeStateRec->IsHole; + if (holeStateRec == outRec2) + outRec1->FirstLeft = outRec2->FirstLeft; + outRec2->FirstLeft = outRec1; + + if (m_UsingPolyTree) FixupFirstLefts3(outRec2, outRec1); + } + } +} + +//------------------------------------------------------------------------------ +// ClipperOffset support functions ... +//------------------------------------------------------------------------------ + +DoublePoint GetUnitNormal(const IntPoint &pt1, const IntPoint &pt2) +{ + if(pt2.X == pt1.X && pt2.Y == pt1.Y) + return DoublePoint(0, 0); + + double Dx = (double)(pt2.X - pt1.X); + double dy = (double)(pt2.Y - pt1.Y); + double f = 1 *1.0/ std::sqrt( Dx*Dx + dy*dy ); + Dx *= f; + dy *= f; + return DoublePoint(dy, -Dx); +} + +//------------------------------------------------------------------------------ +// ClipperOffset class +//------------------------------------------------------------------------------ + +ClipperOffset::ClipperOffset(double miterLimit, double arcTolerance) +{ + this->MiterLimit = miterLimit; + this->ArcTolerance = arcTolerance; + m_lowest.X = -1; + + //Avoid uninitialized vars: + m_delta = m_sinA = m_sin = m_cos = 0; + m_miterLim = m_StepsPerRad = 0; + +} +//------------------------------------------------------------------------------ + +ClipperOffset::~ClipperOffset() +{ + Clear(); +} +//------------------------------------------------------------------------------ + +void ClipperOffset::Clear() +{ + for (int i = 0; i < m_polyNodes.ChildCount(); ++i) + delete m_polyNodes.Childs[i]; + m_polyNodes.Childs.clear(); + m_lowest.X = -1; +} +//------------------------------------------------------------------------------ + +void ClipperOffset::AddPath(const Path& path, JoinType joinType, EndType endType) +{ + int highI = (int)path.size() - 1; + if (highI < 0) return; + PolyNode* newNode = new PolyNode(); + newNode->m_jointype = joinType; + newNode->m_endtype = endType; + + //strip duplicate points from path and also get index to the lowest point ... + if (endType == etClosedLine || endType == etClosedPolygon) + while (highI > 0 && path[0] == path[highI]) highI--; + newNode->Contour.reserve(highI + 1); + newNode->Contour.push_back(path[0]); + int j = 0, k = 0; + for (int i = 1; i <= highI; i++) + if (newNode->Contour[j] != path[i]) + { + j++; + newNode->Contour.push_back(path[i]); + if (path[i].Y > newNode->Contour[k].Y || + (path[i].Y == newNode->Contour[k].Y && + path[i].X < newNode->Contour[k].X)) k = j; + } + if (endType == etClosedPolygon && j < 2) + { + delete newNode; + return; + } + m_polyNodes.AddChild(*newNode); + + //if this path's lowest pt is lower than all the others then update m_lowest + if (endType != etClosedPolygon) return; + if (m_lowest.X < 0) + m_lowest = IntPoint(m_polyNodes.ChildCount() - 1, k); + else + { + IntPoint ip = m_polyNodes.Childs[(int)m_lowest.X]->Contour[(int)m_lowest.Y]; + if (newNode->Contour[k].Y > ip.Y || + (newNode->Contour[k].Y == ip.Y && + newNode->Contour[k].X < ip.X)) + m_lowest = IntPoint(m_polyNodes.ChildCount() - 1, k); + } +} +//------------------------------------------------------------------------------ + +void ClipperOffset::AddPaths(const Paths& paths, JoinType joinType, EndType endType) +{ + for (Paths::size_type i = 0; i < paths.size(); ++i) + AddPath(paths[i], joinType, endType); +} +//------------------------------------------------------------------------------ + +void ClipperOffset::FixOrientations() +{ + //fixup orientations of all closed paths if the orientation of the + //closed path with the lowermost vertex is wrong ... + if (m_lowest.X >= 0 && + !Orientation(m_polyNodes.Childs[(int)m_lowest.X]->Contour)) + { + for (int i = 0; i < m_polyNodes.ChildCount(); ++i) + { + PolyNode& node = *m_polyNodes.Childs[i]; + if (node.m_endtype == etClosedPolygon || + (node.m_endtype == etClosedLine && Orientation(node.Contour))) + ReversePath(node.Contour); + } + } else + { + for (int i = 0; i < m_polyNodes.ChildCount(); ++i) + { + PolyNode& node = *m_polyNodes.Childs[i]; + if (node.m_endtype == etClosedLine && !Orientation(node.Contour)) + ReversePath(node.Contour); + } + } +} +//------------------------------------------------------------------------------ + +void ClipperOffset::Execute(Paths& solution, double delta) +{ + solution.clear(); + FixOrientations(); + DoOffset(delta); + + //now clean up 'corners' ... + Clipper clpr; + clpr.AddPaths(m_destPolys, ptSubject, true); + if (delta > 0) + { + clpr.Execute(ctUnion, solution, pftPositive, pftPositive); + } + else + { + IntRect r = clpr.GetBounds(); + Path outer(4); + outer[0] = IntPoint(r.left - 10, r.bottom + 10); + outer[1] = IntPoint(r.right + 10, r.bottom + 10); + outer[2] = IntPoint(r.right + 10, r.top - 10); + outer[3] = IntPoint(r.left - 10, r.top - 10); + + clpr.AddPath(outer, ptSubject, true); + clpr.ReverseSolution(true); + clpr.Execute(ctUnion, solution, pftNegative, pftNegative); + if (solution.size() > 0) solution.erase(solution.begin()); + } +} +//------------------------------------------------------------------------------ + +void ClipperOffset::Execute(PolyTree& solution, double delta) +{ + solution.Clear(); + FixOrientations(); + DoOffset(delta); + + //now clean up 'corners' ... + Clipper clpr; + clpr.AddPaths(m_destPolys, ptSubject, true); + if (delta > 0) + { + clpr.Execute(ctUnion, solution, pftPositive, pftPositive); + } + else + { + IntRect r = clpr.GetBounds(); + Path outer(4); + outer[0] = IntPoint(r.left - 10, r.bottom + 10); + outer[1] = IntPoint(r.right + 10, r.bottom + 10); + outer[2] = IntPoint(r.right + 10, r.top - 10); + outer[3] = IntPoint(r.left - 10, r.top - 10); + + clpr.AddPath(outer, ptSubject, true); + clpr.ReverseSolution(true); + clpr.Execute(ctUnion, solution, pftNegative, pftNegative); + //remove the outer PolyNode rectangle ... + if (solution.ChildCount() == 1 && solution.Childs[0]->ChildCount() > 0) + { + PolyNode* outerNode = solution.Childs[0]; + solution.Childs.reserve(outerNode->ChildCount()); + solution.Childs[0] = outerNode->Childs[0]; + solution.Childs[0]->Parent = outerNode->Parent; + for (int i = 1; i < outerNode->ChildCount(); ++i) + solution.AddChild(*outerNode->Childs[i]); + } + else + solution.Clear(); + } +} +//------------------------------------------------------------------------------ + +void ClipperOffset::DoOffset(double delta) +{ + m_destPolys.clear(); + m_delta = delta; + + //if Zero offset, just copy any CLOSED polygons to m_p and return ... + if (NEAR_ZERO(delta)) + { + m_destPolys.reserve(m_polyNodes.ChildCount()); + for (int i = 0; i < m_polyNodes.ChildCount(); i++) + { + PolyNode& node = *m_polyNodes.Childs[i]; + if (node.m_endtype == etClosedPolygon) + m_destPolys.push_back(node.Contour); + } + return; + } + + //see offset_triginometry3.svg in the documentation folder ... + if (MiterLimit > 2) m_miterLim = 2/(MiterLimit * MiterLimit); + else m_miterLim = 0.5; + + double y; + if (ArcTolerance <= 0.0) y = def_arc_tolerance; + else if (ArcTolerance > std::fabs(delta) * def_arc_tolerance) + y = std::fabs(delta) * def_arc_tolerance; + else y = ArcTolerance; + //see offset_triginometry2.svg in the documentation folder ... + double steps = pi / std::acos(1 - y / std::fabs(delta)); + if (steps > std::fabs(delta) * pi) + steps = std::fabs(delta) * pi; //ie excessive precision check + m_sin = std::sin(two_pi / steps); + m_cos = std::cos(two_pi / steps); + m_StepsPerRad = steps / two_pi; + if (delta < 0.0) m_sin = -m_sin; + + m_destPolys.reserve(m_polyNodes.ChildCount() * 2); + for (int i = 0; i < m_polyNodes.ChildCount(); i++) + { + PolyNode& node = *m_polyNodes.Childs[i]; + m_srcPoly = node.Contour; + + int len = (int)m_srcPoly.size(); + if (len == 0 || (delta <= 0 && (len < 3 || node.m_endtype != etClosedPolygon))) + continue; + + m_destPoly.clear(); + if (len == 1) + { + if (node.m_jointype == jtRound) + { + double X = 1.0, Y = 0.0; + for (cInt j = 1; j <= steps; j++) + { + m_destPoly.push_back(IntPoint( + Round(m_srcPoly[0].X + X * delta), + Round(m_srcPoly[0].Y + Y * delta))); + double X2 = X; + X = X * m_cos - m_sin * Y; + Y = X2 * m_sin + Y * m_cos; + } + } + else + { + double X = -1.0, Y = -1.0; + for (int j = 0; j < 4; ++j) + { + m_destPoly.push_back(IntPoint( + Round(m_srcPoly[0].X + X * delta), + Round(m_srcPoly[0].Y + Y * delta))); + if (X < 0) X = 1; + else if (Y < 0) Y = 1; + else X = -1; + } + } + m_destPolys.push_back(m_destPoly); + continue; + } + //build m_normals ... + m_normals.clear(); + m_normals.reserve(len); + for (int j = 0; j < len - 1; ++j) + m_normals.push_back(GetUnitNormal(m_srcPoly[j], m_srcPoly[j + 1])); + if (node.m_endtype == etClosedLine || node.m_endtype == etClosedPolygon) + m_normals.push_back(GetUnitNormal(m_srcPoly[len - 1], m_srcPoly[0])); + else + m_normals.push_back(DoublePoint(m_normals[len - 2])); + + if (node.m_endtype == etClosedPolygon) + { + int k = len - 1; + for (int j = 0; j < len; ++j) + OffsetPoint(j, k, node.m_jointype); + m_destPolys.push_back(m_destPoly); + } + else if (node.m_endtype == etClosedLine) + { + int k = len - 1; + for (int j = 0; j < len; ++j) + OffsetPoint(j, k, node.m_jointype); + m_destPolys.push_back(m_destPoly); + m_destPoly.clear(); + //re-build m_normals ... + DoublePoint n = m_normals[len -1]; + for (int j = len - 1; j > 0; j--) + m_normals[j] = DoublePoint(-m_normals[j - 1].X, -m_normals[j - 1].Y); + m_normals[0] = DoublePoint(-n.X, -n.Y); + k = 0; + for (int j = len - 1; j >= 0; j--) + OffsetPoint(j, k, node.m_jointype); + m_destPolys.push_back(m_destPoly); + } + else + { + int k = 0; + for (int j = 1; j < len - 1; ++j) + OffsetPoint(j, k, node.m_jointype); + + IntPoint pt1; + if (node.m_endtype == etOpenButt) + { + int j = len - 1; + pt1 = IntPoint((cInt)Round(m_srcPoly[j].X + m_normals[j].X * + delta), (cInt)Round(m_srcPoly[j].Y + m_normals[j].Y * delta)); + m_destPoly.push_back(pt1); + pt1 = IntPoint((cInt)Round(m_srcPoly[j].X - m_normals[j].X * + delta), (cInt)Round(m_srcPoly[j].Y - m_normals[j].Y * delta)); + m_destPoly.push_back(pt1); + } + else + { + int j = len - 1; + k = len - 2; + m_sinA = 0; + m_normals[j] = DoublePoint(-m_normals[j].X, -m_normals[j].Y); + if (node.m_endtype == etOpenSquare) + DoSquare(j, k); + else + DoRound(j, k); + } + + //re-build m_normals ... + for (int j = len - 1; j > 0; j--) + m_normals[j] = DoublePoint(-m_normals[j - 1].X, -m_normals[j - 1].Y); + m_normals[0] = DoublePoint(-m_normals[1].X, -m_normals[1].Y); + + k = len - 1; + for (int j = k - 1; j > 0; --j) OffsetPoint(j, k, node.m_jointype); + + if (node.m_endtype == etOpenButt) + { + pt1 = IntPoint((cInt)Round(m_srcPoly[0].X - m_normals[0].X * delta), + (cInt)Round(m_srcPoly[0].Y - m_normals[0].Y * delta)); + m_destPoly.push_back(pt1); + pt1 = IntPoint((cInt)Round(m_srcPoly[0].X + m_normals[0].X * delta), + (cInt)Round(m_srcPoly[0].Y + m_normals[0].Y * delta)); + m_destPoly.push_back(pt1); + } + else + { + k = 1; + m_sinA = 0; + if (node.m_endtype == etOpenSquare) + DoSquare(0, 1); + else + DoRound(0, 1); + } + m_destPolys.push_back(m_destPoly); + } + } +} +//------------------------------------------------------------------------------ + +void ClipperOffset::OffsetPoint(int j, int& k, JoinType jointype) +{ + //cross product ... + m_sinA = (m_normals[k].X * m_normals[j].Y - m_normals[j].X * m_normals[k].Y); + if (std::fabs(m_sinA * m_delta) < 1.0) + { + //dot product ... + double cosA = (m_normals[k].X * m_normals[j].X + m_normals[j].Y * m_normals[k].Y ); + if (cosA > 0) // angle => 0 degrees + { + m_destPoly.push_back(IntPoint(Round(m_srcPoly[j].X + m_normals[k].X * m_delta), + Round(m_srcPoly[j].Y + m_normals[k].Y * m_delta))); + return; + } + //else angle => 180 degrees + } + else if (m_sinA > 1.0) m_sinA = 1.0; + else if (m_sinA < -1.0) m_sinA = -1.0; + + if (m_sinA * m_delta < 0) + { + m_destPoly.push_back(IntPoint(Round(m_srcPoly[j].X + m_normals[k].X * m_delta), + Round(m_srcPoly[j].Y + m_normals[k].Y * m_delta))); + m_destPoly.push_back(m_srcPoly[j]); + m_destPoly.push_back(IntPoint(Round(m_srcPoly[j].X + m_normals[j].X * m_delta), + Round(m_srcPoly[j].Y + m_normals[j].Y * m_delta))); + } + else + switch (jointype) + { + case jtMiter: + { + double r = 1 + (m_normals[j].X * m_normals[k].X + + m_normals[j].Y * m_normals[k].Y); + if (r >= m_miterLim) DoMiter(j, k, r); else DoSquare(j, k); + break; + } + case jtSquare: DoSquare(j, k); break; + case jtRound: DoRound(j, k); break; + } + k = j; +} +//------------------------------------------------------------------------------ + +void ClipperOffset::DoSquare(int j, int k) +{ + double dx = std::tan(std::atan2(m_sinA, + m_normals[k].X * m_normals[j].X + m_normals[k].Y * m_normals[j].Y) / 4); + m_destPoly.push_back(IntPoint( + Round(m_srcPoly[j].X + m_delta * (m_normals[k].X - m_normals[k].Y * dx)), + Round(m_srcPoly[j].Y + m_delta * (m_normals[k].Y + m_normals[k].X * dx)))); + m_destPoly.push_back(IntPoint( + Round(m_srcPoly[j].X + m_delta * (m_normals[j].X + m_normals[j].Y * dx)), + Round(m_srcPoly[j].Y + m_delta * (m_normals[j].Y - m_normals[j].X * dx)))); +} +//------------------------------------------------------------------------------ + +void ClipperOffset::DoMiter(int j, int k, double r) +{ + double q = m_delta / r; + m_destPoly.push_back(IntPoint(Round(m_srcPoly[j].X + (m_normals[k].X + m_normals[j].X) * q), + Round(m_srcPoly[j].Y + (m_normals[k].Y + m_normals[j].Y) * q))); +} +//------------------------------------------------------------------------------ + +void ClipperOffset::DoRound(int j, int k) +{ + double a = std::atan2(m_sinA, + m_normals[k].X * m_normals[j].X + m_normals[k].Y * m_normals[j].Y); + int steps = std::max((int)Round(m_StepsPerRad * std::fabs(a)), 1); + + double X = m_normals[k].X, Y = m_normals[k].Y, X2; + for (int i = 0; i < steps; ++i) + { + m_destPoly.push_back(IntPoint( + Round(m_srcPoly[j].X + X * m_delta), + Round(m_srcPoly[j].Y + Y * m_delta))); + X2 = X; + X = X * m_cos - m_sin * Y; + Y = X2 * m_sin + Y * m_cos; + } + m_destPoly.push_back(IntPoint( + Round(m_srcPoly[j].X + m_normals[j].X * m_delta), + Round(m_srcPoly[j].Y + m_normals[j].Y * m_delta))); +} + +//------------------------------------------------------------------------------ +// Miscellaneous public functions +//------------------------------------------------------------------------------ + +void Clipper::DoSimplePolygons() +{ + PolyOutList::size_type i = 0; + while (i < m_PolyOuts.size()) + { + OutRec* outrec = m_PolyOuts[i++]; + OutPt* op = outrec->Pts; + if (!op || outrec->IsOpen) continue; + do //for each Pt in Polygon until duplicate found do ... + { + OutPt* op2 = op->Next; + while (op2 != outrec->Pts) + { + if ((op->Pt == op2->Pt) && op2->Next != op && op2->Prev != op) + { + //split the polygon into two ... + OutPt* op3 = op->Prev; + OutPt* op4 = op2->Prev; + op->Prev = op4; + op4->Next = op; + op2->Prev = op3; + op3->Next = op2; + + outrec->Pts = op; + OutRec* outrec2 = CreateOutRec(); + outrec2->Pts = op2; + UpdateOutPtIdxs(*outrec2); + if (Poly2ContainsPoly1(outrec2->Pts, outrec->Pts)) + { + //OutRec2 is contained by OutRec1 ... + outrec2->IsHole = !outrec->IsHole; + outrec2->FirstLeft = outrec; + if (m_UsingPolyTree) FixupFirstLefts2(outrec2, outrec); + } + else + if (Poly2ContainsPoly1(outrec->Pts, outrec2->Pts)) + { + //OutRec1 is contained by OutRec2 ... + outrec2->IsHole = outrec->IsHole; + outrec->IsHole = !outrec2->IsHole; + outrec2->FirstLeft = outrec->FirstLeft; + outrec->FirstLeft = outrec2; + if (m_UsingPolyTree) FixupFirstLefts2(outrec, outrec2); + } + else + { + //the 2 polygons are separate ... + outrec2->IsHole = outrec->IsHole; + outrec2->FirstLeft = outrec->FirstLeft; + if (m_UsingPolyTree) FixupFirstLefts1(outrec, outrec2); + } + op2 = op; //ie get ready for the Next iteration + } + op2 = op2->Next; + } + op = op->Next; + } + while (op != outrec->Pts); + } +} +//------------------------------------------------------------------------------ + +void ReversePath(Path& p) +{ + std::reverse(p.begin(), p.end()); +} +//------------------------------------------------------------------------------ + +void ReversePaths(Paths& p) +{ + for (Paths::size_type i = 0; i < p.size(); ++i) + ReversePath(p[i]); +} +//------------------------------------------------------------------------------ + +void SimplifyPolygon(const Path &in_poly, Paths &out_polys, PolyFillType fillType) +{ + Clipper c; + c.StrictlySimple(true); + c.AddPath(in_poly, ptSubject, true); + c.Execute(ctUnion, out_polys, fillType, fillType); +} +//------------------------------------------------------------------------------ + +void SimplifyPolygons(const Paths &in_polys, Paths &out_polys, PolyFillType fillType) +{ + Clipper c; + c.StrictlySimple(true); + c.AddPaths(in_polys, ptSubject, true); + c.Execute(ctUnion, out_polys, fillType, fillType); +} +//------------------------------------------------------------------------------ + +void SimplifyPolygons(Paths &polys, PolyFillType fillType) +{ + SimplifyPolygons(polys, polys, fillType); +} +//------------------------------------------------------------------------------ + +inline double DistanceSqrd(const IntPoint& pt1, const IntPoint& pt2) +{ + double Dx = ((double)pt1.X - pt2.X); + double dy = ((double)pt1.Y - pt2.Y); + return (Dx*Dx + dy*dy); +} +//------------------------------------------------------------------------------ + +double DistanceFromLineSqrd( + const IntPoint& pt, const IntPoint& ln1, const IntPoint& ln2) +{ + //The equation of a line in general form (Ax + By + C = 0) + //given 2 points (x¹,y¹) & (x²,y²) is ... + //(y¹ - y²)x + (x² - x¹)y + (y² - y¹)x¹ - (x² - x¹)y¹ = 0 + //A = (y¹ - y²); B = (x² - x¹); C = (y² - y¹)x¹ - (x² - x¹)y¹ + //perpendicular distance of point (x³,y³) = (Ax³ + By³ + C)/Sqrt(A² + B²) + //see http://en.wikipedia.org/wiki/Perpendicular_distance + double A = double(ln1.Y - ln2.Y); + double B = double(ln2.X - ln1.X); + double C = A * ln1.X + B * ln1.Y; + C = A * pt.X + B * pt.Y - C; + return (C * C) / (A * A + B * B); +} +//--------------------------------------------------------------------------- + +bool SlopesNearCollinear(const IntPoint& pt1, + const IntPoint& pt2, const IntPoint& pt3, double distSqrd) +{ + //this function is more accurate when the point that's geometrically + //between the other 2 points is the one that's tested for distance. + //ie makes it more likely to pick up 'spikes' ... + if (Abs(pt1.X - pt2.X) > Abs(pt1.Y - pt2.Y)) + { + if ((pt1.X > pt2.X) == (pt1.X < pt3.X)) + return DistanceFromLineSqrd(pt1, pt2, pt3) < distSqrd; + else if ((pt2.X > pt1.X) == (pt2.X < pt3.X)) + return DistanceFromLineSqrd(pt2, pt1, pt3) < distSqrd; + else + return DistanceFromLineSqrd(pt3, pt1, pt2) < distSqrd; + } + else + { + if ((pt1.Y > pt2.Y) == (pt1.Y < pt3.Y)) + return DistanceFromLineSqrd(pt1, pt2, pt3) < distSqrd; + else if ((pt2.Y > pt1.Y) == (pt2.Y < pt3.Y)) + return DistanceFromLineSqrd(pt2, pt1, pt3) < distSqrd; + else + return DistanceFromLineSqrd(pt3, pt1, pt2) < distSqrd; + } +} +//------------------------------------------------------------------------------ + +bool PointsAreClose(IntPoint pt1, IntPoint pt2, double distSqrd) +{ + double Dx = (double)pt1.X - pt2.X; + double dy = (double)pt1.Y - pt2.Y; + return ((Dx * Dx) + (dy * dy) <= distSqrd); +} +//------------------------------------------------------------------------------ + +OutPt* ExcludeOp(OutPt* op) +{ + OutPt* result = op->Prev; + result->Next = op->Next; + op->Next->Prev = result; + result->Idx = 0; + return result; +} +//------------------------------------------------------------------------------ + +void CleanPolygon(const Path& in_poly, Path& out_poly, double distance) +{ + //distance = proximity in units/pixels below which vertices + //will be stripped. Default ~= sqrt(2). + + size_t size = in_poly.size(); + + if (size == 0) + { + out_poly.clear(); + return; + } + + OutPt* outPts = new OutPt[size]; + for (size_t i = 0; i < size; ++i) + { + outPts[i].Pt = in_poly[i]; + outPts[i].Next = &outPts[(i + 1) % size]; + outPts[i].Next->Prev = &outPts[i]; + outPts[i].Idx = 0; + } + + double distSqrd = distance * distance; + OutPt* op = &outPts[0]; + while (op->Idx == 0 && op->Next != op->Prev) + { + if (PointsAreClose(op->Pt, op->Prev->Pt, distSqrd)) + { + op = ExcludeOp(op); + size--; + } + else if (PointsAreClose(op->Prev->Pt, op->Next->Pt, distSqrd)) + { + ExcludeOp(op->Next); + op = ExcludeOp(op); + size -= 2; + } + else if (SlopesNearCollinear(op->Prev->Pt, op->Pt, op->Next->Pt, distSqrd)) + { + op = ExcludeOp(op); + size--; + } + else + { + op->Idx = 1; + op = op->Next; + } + } + + if (size < 3) size = 0; + out_poly.resize(size); + for (size_t i = 0; i < size; ++i) + { + out_poly[i] = op->Pt; + op = op->Next; + } + delete [] outPts; +} +//------------------------------------------------------------------------------ + +void CleanPolygon(Path& poly, double distance) +{ + CleanPolygon(poly, poly, distance); +} +//------------------------------------------------------------------------------ + +void CleanPolygons(const Paths& in_polys, Paths& out_polys, double distance) +{ + out_polys.resize(in_polys.size()); + for (Paths::size_type i = 0; i < in_polys.size(); ++i) + CleanPolygon(in_polys[i], out_polys[i], distance); +} +//------------------------------------------------------------------------------ + +void CleanPolygons(Paths& polys, double distance) +{ + CleanPolygons(polys, polys, distance); +} +//------------------------------------------------------------------------------ + +void Minkowski(const Path& poly, const Path& path, + Paths& solution, bool isSum, bool isClosed) +{ + int delta = (isClosed ? 1 : 0); + size_t polyCnt = poly.size(); + size_t pathCnt = path.size(); + Paths pp; + pp.reserve(pathCnt); + if (isSum) + for (size_t i = 0; i < pathCnt; ++i) + { + Path p; + p.reserve(polyCnt); + for (size_t j = 0; j < poly.size(); ++j) + p.push_back(IntPoint(path[i].X + poly[j].X, path[i].Y + poly[j].Y)); + pp.push_back(p); + } + else + for (size_t i = 0; i < pathCnt; ++i) + { + Path p; + p.reserve(polyCnt); + for (size_t j = 0; j < poly.size(); ++j) + p.push_back(IntPoint(path[i].X - poly[j].X, path[i].Y - poly[j].Y)); + pp.push_back(p); + } + + solution.clear(); + solution.reserve((pathCnt + delta) * (polyCnt + 1)); + for (size_t i = 0; i < pathCnt - 1 + delta; ++i) + for (size_t j = 0; j < polyCnt; ++j) + { + Path quad; + quad.reserve(4); + quad.push_back(pp[i % pathCnt][j % polyCnt]); + quad.push_back(pp[(i + 1) % pathCnt][j % polyCnt]); + quad.push_back(pp[(i + 1) % pathCnt][(j + 1) % polyCnt]); + quad.push_back(pp[i % pathCnt][(j + 1) % polyCnt]); + if (!Orientation(quad)) ReversePath(quad); + solution.push_back(quad); + } +} +//------------------------------------------------------------------------------ + +void MinkowskiSum(const Path& pattern, const Path& path, Paths& solution, bool pathIsClosed) +{ + Minkowski(pattern, path, solution, true, pathIsClosed); + Clipper c; + c.AddPaths(solution, ptSubject, true); + c.Execute(ctUnion, solution, pftNonZero, pftNonZero); +} +//------------------------------------------------------------------------------ + +void TranslatePath(const Path& input, Path& output, const IntPoint delta) +{ + //precondition: input != output + output.resize(input.size()); + for (size_t i = 0; i < input.size(); ++i) + output[i] = IntPoint(input[i].X + delta.X, input[i].Y + delta.Y); +} +//------------------------------------------------------------------------------ + +void MinkowskiSum(const Path& pattern, const Paths& paths, Paths& solution, bool pathIsClosed) +{ + Clipper c; + for (size_t i = 0; i < paths.size(); ++i) + { + Paths tmp; + Minkowski(pattern, paths[i], tmp, true, pathIsClosed); + c.AddPaths(tmp, ptSubject, true); + if (pathIsClosed) + { + Path tmp2; + TranslatePath(paths[i], tmp2, pattern[0]); + c.AddPath(tmp2, ptClip, true); + } + } + c.Execute(ctUnion, solution, pftNonZero, pftNonZero); +} +//------------------------------------------------------------------------------ + +void MinkowskiDiff(const Path& poly1, const Path& poly2, Paths& solution) +{ + Minkowski(poly1, poly2, solution, false, true); + Clipper c; + c.AddPaths(solution, ptSubject, true); + c.Execute(ctUnion, solution, pftNonZero, pftNonZero); +} +//------------------------------------------------------------------------------ + +enum NodeType {ntAny, ntOpen, ntClosed}; + +void AddPolyNodeToPaths(const PolyNode& polynode, NodeType nodetype, Paths& paths) +{ + bool match = true; + if (nodetype == ntClosed) match = !polynode.IsOpen(); + else if (nodetype == ntOpen) return; + + if (!polynode.Contour.empty() && match) + paths.push_back(polynode.Contour); + for (int i = 0; i < polynode.ChildCount(); ++i) + AddPolyNodeToPaths(*polynode.Childs[i], nodetype, paths); +} +//------------------------------------------------------------------------------ + +void PolyTreeToPaths(const PolyTree& polytree, Paths& paths) +{ + paths.resize(0); + paths.reserve(polytree.Total()); + AddPolyNodeToPaths(polytree, ntAny, paths); +} +//------------------------------------------------------------------------------ + +void ClosedPathsFromPolyTree(const PolyTree& polytree, Paths& paths) +{ + paths.resize(0); + paths.reserve(polytree.Total()); + AddPolyNodeToPaths(polytree, ntClosed, paths); +} +//------------------------------------------------------------------------------ + +void OpenPathsFromPolyTree(PolyTree& polytree, Paths& paths) +{ + paths.resize(0); + paths.reserve(polytree.Total()); + //Open paths are top level only, so ... + for (int i = 0; i < polytree.ChildCount(); ++i) + if (polytree.Childs[i]->IsOpen()) + paths.push_back(polytree.Childs[i]->Contour); +} +//------------------------------------------------------------------------------ + +std::ostream& operator <<(std::ostream &s, const IntPoint &p) +{ + s << "(" << p.X << "," << p.Y << ")"; + return s; +} +//------------------------------------------------------------------------------ + +std::ostream& operator <<(std::ostream &s, const Path &p) +{ + if (p.empty()) return s; + Path::size_type last = p.size() -1; + for (Path::size_type i = 0; i < last; i++) + s << "(" << p[i].X << "," << p[i].Y << "), "; + s << "(" << p[last].X << "," << p[last].Y << ")\n"; + return s; +} +//------------------------------------------------------------------------------ + +std::ostream& operator <<(std::ostream &s, const Paths &p) +{ + for (Paths::size_type i = 0; i < p.size(); i++) + s << p[i]; + s << "\n"; + return s; +} +//------------------------------------------------------------------------------ + +} //ClipperLib namespace |