/*******************************************************************************
* *
* Author : Angus Johnson *
* Version : 6.4.2 *
* Date : 27 February 2017 *
* Website : http://www.angusj.com *
* Copyright : Angus Johnson 2010-2017 *
* *
* License: *
* Use, modification & distribution is subject to Boost Software License Ver 1. *
* http://www.boost.org/LICENSE_1_0.txt *
* *
* Attributions: *
* The code in this library is an extension of Bala Vatti's clipping algorithm: *
* "A generic solution to polygon clipping" *
* Communications of the ACM, Vol 35, Issue 7 (July 1992) pp 56-63. *
* http://portal.acm.org/citation.cfm?id=129906 *
* *
* Computer graphics and geometric modeling: implementation and algorithms *
* By Max K. Agoston *
* Springer; 1 edition (January 4, 2005) *
* http://books.google.com/books?q=vatti+clipping+agoston *
* *
* See also: *
* "Polygon Offsetting by Computing Winding Numbers" *
* Paper no. DETC2005-85513 pp. 565-575 *
* ASME 2005 International Design Engineering Technical Conferences *
* and Computers and Information in Engineering Conference (IDETC/CIE2005) *
* September 24-28, 2005 , Long Beach, California, USA *
* http://www.me.berkeley.edu/~mcmains/pubs/DAC05OffsetPolygon.pdf *
* *
*******************************************************************************/
/*******************************************************************************
* *
* This is a translation of the Delphi Clipper library and the naming style *
* used has retained a Delphi flavour. *
* *
*******************************************************************************/
#include <algorithm>
#include <cmath>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <ostream>
#include <stdexcept>
#include <vector>
#include "include/clipper.h"
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() : Parent(0), Index(0), m_IsOpen(false) {}
//------------------------------------------------------------------------------
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, int(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;
}
//------------------------------------------------------------------------------
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
}
//------------------------------------------------------------------------------
#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 && prevE->Top.Y < Pt.Y && e->Top.Y < Pt.Y) {
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 || !rb) {
// 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
{
#ifdef use_xyz
if (dir == dLeftToRight)
SetZ(e->Curr, *horzEdge, *e);
else
SetZ(e->Curr, *e, *horzEdge);
#endif
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;
#ifdef use_xyz
e->Curr.Z =
topY == e->Top.Y ? e->Top.Z : (topY == e->Bot.Y ? e->Bot.Z : 0);
#endif
}
// 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 && 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;
}
//------------------------------------------------------------------------------
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 (x�,y�) & (x�,y�) is ...
//(y� - y�)x + (x� - x�)y + (y� - y�)x� - (x� - x�)y� = 0
// A = (y� - y�); B = (x� - x�); C = (y� - y�)x� - (x� - x�)y�
// perpendicular distance of point (x�,y�) = (Ax� + By� + C)/Sqrt(A� + B�)
// 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