diff --git a/src/UglyToad.PdfPig.Core/PdfSubpath.cs b/src/UglyToad.PdfPig.Core/PdfSubpath.cs index fdeb89fa..58d29751 100644 --- a/src/UglyToad.PdfPig.Core/PdfSubpath.cs +++ b/src/UglyToad.PdfPig.Core/PdfSubpath.cs @@ -238,9 +238,9 @@ } /// - /// Gets a which entirely contains the geometry of the defined path. + /// Gets a which entirely contains the geometry of the defined subpath. /// - /// For paths which don't define any geometry this returns . + /// For subpaths which don't define any geometry this returns . public PdfRectangle? GetBoundingRectangle() { if (commands.Count == 0) diff --git a/src/UglyToad.PdfPig/Geometry/Clipping.cs b/src/UglyToad.PdfPig/Geometry/Clipping.cs index e1e89318..1de422c7 100644 --- a/src/UglyToad.PdfPig/Geometry/Clipping.cs +++ b/src/UglyToad.PdfPig/Geometry/Clipping.cs @@ -1,6 +1,11 @@ namespace UglyToad.PdfPig.Geometry { + using System; + using System.Collections.Generic; + using System.Linq; + using UglyToad.PdfPig.Core; using UglyToad.PdfPig.Graphics; + using static UglyToad.PdfPig.Core.PdfSubpath; /// /// @@ -8,16 +13,172 @@ internal static class Clipping { const double factor = 10_000.0; + const int linesInCurve = 10; // number of lines to use when transforming bezier curve to polyline. - /// - /// DOES NOTHING - /// - /// - /// - /// public static PdfPath Clip(this PdfPath clipping, PdfPath subject) { - return subject; + if (clipping == null) + { + throw new ArgumentNullException(nameof(clipping), "Clip(): the clipping path cannot be null."); + } + + if (!clipping.IsClipping) + { + throw new ArgumentException("Clip(): the clipping path does not have the IsClipping flag set to true.", nameof(clipping)); + } + + if (subject == null) + { + throw new ArgumentNullException(nameof(subject), "Clip(): the subject path cannot be null."); + } + + if (subject.Count == 0) + { + return subject; + } + + Clipper clipper = new Clipper(); + + // Clipping path + foreach (var subPathClipping in clipping) + { + if (subPathClipping.Commands.Count == 0) + { + continue; + } + + // Force close clipping polygon + if (!subPathClipping.IsClosed()) + { + subPathClipping.CloseSubpath(); + } + + clipper.AddPath(subPathClipping.ToClipperPolygon().ToList(), PolyType.ptClip, true); + } + + // Subject path + // Filled and clipping path need to be closed + bool subjectClose = subject.IsFilled || subject.IsClipping; + foreach (var subPathSubject in subject) + { + if (subPathSubject.Commands.Count == 0) + { + continue; + } + + // Force close subject if need be + if (subjectClose && !subPathSubject.IsClosed()) + { + subPathSubject.CloseSubpath(); + } + + clipper.AddPath(subPathSubject.ToClipperPolygon().ToList(), PolyType.ptSubject, subjectClose); + } + + var clippingFillType = clipping.FillingRule == FillingRule.NonZeroWinding ? PolyFillType.pftNonZero : PolyFillType.pftEvenOdd; + var subjectFillType = subject.FillingRule == FillingRule.NonZeroWinding ? PolyFillType.pftNonZero : PolyFillType.pftEvenOdd; + + if (!subjectClose) + { + PdfPath clippedPath = subject.CloneEmpty(); + + // Case where subject is not closed + var solutions = new PolyTree(); + if (clipper.Execute(ClipType.ctIntersection, solutions, subjectFillType, clippingFillType)) + { + foreach (var solution in solutions.Childs) + { + if (solution.Contour.Count > 0) + { + PdfSubpath clippedSubpath = new PdfSubpath(); + clippedSubpath.MoveTo(solution.Contour[0].X / factor, solution.Contour[0].Y / factor); + + for (int i = 1; i < solution.Contour.Count; i++) + { + clippedSubpath.LineTo(solution.Contour[i].X / factor, solution.Contour[i].Y / factor); + } + clippedPath.Add(clippedSubpath); + } + } + if (clippedPath.Count > 0) return clippedPath; + } + return null; + } + else + { + PdfPath clippedPath = subject.CloneEmpty(); + + // Case where subject is closed + var solutions = new List>(); + if (clipper.Execute(ClipType.ctIntersection, solutions, subjectFillType, clippingFillType)) + { + foreach (var solution in solutions) + { + if (solution.Count > 0) + { + PdfSubpath clippedSubpath = new PdfSubpath(); + clippedSubpath.MoveTo(solution[0].X / factor, solution[0].Y / factor); + + for (int i = 1; i < solution.Count; i++) + { + clippedSubpath.LineTo(solution[i].X / factor, solution[i].Y / factor); + } + clippedSubpath.CloseSubpath(); + clippedPath.Add(clippedSubpath); + } + } + if (clippedPath.Count > 0) return clippedPath; + } + return null; + } + } + + /// + /// Allows duplicate points as they will be removed by Clipper. + /// + private static IEnumerable ToClipperPolygon(this PdfSubpath pdfPath) + { + if (pdfPath.Commands.Count == 0) + { + yield break; + } + + if (pdfPath.Commands[0] is Move currentMove) + { + var previous = new IntPoint(currentMove.Location.X * factor, currentMove.Location.Y * factor); + yield return previous; + if (pdfPath.Commands.Count == 1) yield break; + } + else + { + throw new ArgumentException("ToClipperPolygon(): First command is not a Move command. Type is '" + pdfPath.Commands[0].GetType().ToString() + "'.", nameof(pdfPath)); + } + + for (int i = 1; i < pdfPath.Commands.Count; i++) + { + var command = pdfPath.Commands[i]; + if (command is Move move) + { + throw new ArgumentException("ToClipperPolygon():only one move allowed per subpath.", nameof(pdfPath)); + } + else if (command is Line line) + { + yield return new IntPoint(line.From.X * factor, line.From.Y * factor); + yield return new IntPoint(line.To.X * factor, line.To.Y * factor); + } + else if (command is BezierCurve curve) + { + foreach (var lineB in curve.ToLines(linesInCurve)) + { + yield return new IntPoint(lineB.From.X * factor, lineB.From.Y * factor); + yield return new IntPoint(lineB.To.X * factor, lineB.To.Y * factor); + } + } + else if (command is Close) + { + yield return new IntPoint(currentMove.Location.X * factor, currentMove.Location.Y * factor); + } + } } } } diff --git a/src/UglyToad.PdfPig/Geometry/clipper.cs b/src/UglyToad.PdfPig/Geometry/clipper.cs new file mode 100644 index 00000000..0d0efeeb --- /dev/null +++ b/src/UglyToad.PdfPig/Geometry/clipper.cs @@ -0,0 +1,4792 @@ +/******************************************************************************* +* * +* 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. * +* * +*******************************************************************************/ + +/******************************************************************************* +* Boost Software License - Version 1.0 - August 17th, 2003 * +* * +* Permission is hereby granted, free of charge, to any person or organization * +* obtaining a copy of the software and accompanying documentation covered by * +* this license (the "Software") to use, reproduce, display, distribute, * +* execute, and transmit the Software, and to prepare derivative works of the * +* Software, and to permit third-parties to whom the Software is furnished to * +* do so, all subject to the following: * +* * +* The copyright notices in the Software and this entire statement, including * +* the above license grant, this restriction and the following disclaimer, * +* must be included in all copies of the Software, in whole or in part, and * +* all derivative works of the Software, unless such copies or derivative * +* works are solely in the form of machine-executable object code generated by * +* a source language processor. * +* * +* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * +* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * +* FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT * +* SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE * +* FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, * +* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * +* DEALINGS IN THE SOFTWARE. * +*******************************************************************************/ + +/******************************************************************************* +* * +* Code modified for PdfPig * +* * +*******************************************************************************/ + + +//use_lines: Enables open path clipping. Adds a very minor cost to performance. + +using System; +using System.Collections.Generic; + +namespace UglyToad.PdfPig.Geometry +{ + internal struct DoublePoint + { + public double X; + + public double Y; + + public DoublePoint(double x = 0, double y = 0) + { + this.X = x; this.Y = y; + } + + public DoublePoint(DoublePoint dp) + { + this.X = dp.X; this.Y = dp.Y; + } + + public DoublePoint(IntPoint ip) + { + this.X = ip.X; this.Y = ip.Y; + } + }; + + + //------------------------------------------------------------------------------ + // PolyTree & PolyNode classes + //------------------------------------------------------------------------------ + + internal class PolyTree : PolyNode + { + internal List m_AllPolys = new List(); + + //The GC probably handles this cleanup more efficiently ... + //~PolyTree(){Clear();} + + public void Clear() + { + for (int i = 0; i < m_AllPolys.Count; i++) + m_AllPolys[i] = null; + m_AllPolys.Clear(); + m_Childs.Clear(); + } + + public PolyNode GetFirst() + { + if (m_Childs.Count > 0) + return m_Childs[0]; + else + return null; + } + + public int Total + { + get + { + int result = m_AllPolys.Count; + //with negative offsets, ignore the hidden outer polygon ... + if (result > 0 && m_Childs[0] != m_AllPolys[0]) result--; + return result; + } + } + } + + internal class PolyNode + { + internal PolyNode m_Parent; + internal List m_polygon = new List(); + internal int m_Index; + internal JoinType m_jointype; + internal EndType m_endtype; + internal List m_Childs = new List(); + + private bool IsHoleNode() + { + bool result = true; + PolyNode node = m_Parent; + while (node != null) + { + result = !result; + node = node.m_Parent; + } + return result; + } + + public int ChildCount + { + get { return m_Childs.Count; } + } + + public List Contour + { + get { return m_polygon; } + } + + internal void AddChild(PolyNode Child) + { + int cnt = m_Childs.Count; + m_Childs.Add(Child); + Child.m_Parent = this; + Child.m_Index = cnt; + } + + public PolyNode GetNext() + { + if (m_Childs.Count > 0) + return m_Childs[0]; + else + return GetNextSiblingUp(); + } + + internal PolyNode GetNextSiblingUp() + { + if (m_Parent == null) + return null; + else if (m_Index == m_Parent.m_Childs.Count - 1) + return m_Parent.GetNextSiblingUp(); + else + return m_Parent.m_Childs[m_Index + 1]; + } + public List Childs + { + get { return m_Childs; } + } + + public PolyNode Parent + { + get { return m_Parent; } + } + + public bool IsHole + { + get { return IsHoleNode(); } + } + + public bool IsOpen { get; set; } + } + + //------------------------------------------------------------------------------ + // Int128 struct (enables safe math on signed 64bit integers) + // eg Int128 val1((long)9223372036854775807); //ie 2^63 -1 + // Int128 val2((long)9223372036854775807); + // Int128 val3 = val1 * val2; + // val3.ToString => "85070591730234615847396907784232501249" (8.5e+37) + //------------------------------------------------------------------------------ + + internal struct Int128 + { + private long hi; + private ulong lo; + + public Int128(long _lo) + { + lo = (ulong)_lo; + if (_lo < 0) hi = -1; + else hi = 0; + } + + public Int128(long _hi, ulong _lo) + { + lo = _lo; + hi = _hi; + } + + public Int128(Int128 val) + { + hi = val.hi; + lo = val.lo; + } + + public bool IsNegative() + { + return hi < 0; + } + + public static bool operator ==(Int128 val1, Int128 val2) + { + if ((object)val1 == (object)val2) return true; + else if ((object)val1 is null || (object)val2 is null) return false; + return (val1.hi == val2.hi && val1.lo == val2.lo); + } + + public static bool operator !=(Int128 val1, Int128 val2) + { + return !(val1 == val2); + } + + public override bool Equals(object obj) + { + if (obj == null || !(obj is Int128)) + return false; + Int128 i128 = (Int128)obj; + return (i128.hi == hi && i128.lo == lo); + } + + public override int GetHashCode() + { + return hi.GetHashCode() ^ lo.GetHashCode(); + } + + public static bool operator >(Int128 val1, Int128 val2) + { + if (val1.hi != val2.hi) + return val1.hi > val2.hi; + else + return val1.lo > val2.lo; + } + + public static bool operator <(Int128 val1, Int128 val2) + { + if (val1.hi != val2.hi) + return val1.hi < val2.hi; + else + return val1.lo < val2.lo; + } + + public static Int128 operator +(Int128 lhs, Int128 rhs) + { + lhs.hi += rhs.hi; + lhs.lo += rhs.lo; + if (lhs.lo < rhs.lo) lhs.hi++; + return lhs; + } + + public static Int128 operator -(Int128 lhs, Int128 rhs) + { + return lhs + -rhs; + } + + public static Int128 operator -(Int128 val) + { + if (val.lo == 0) + return new Int128(-val.hi, 0); + else + return new Int128(~val.hi, ~val.lo + 1); + } + + public static explicit operator double(Int128 val) + { + const double shift64 = 18446744073709551616.0; //2^64 + if (val.hi < 0) + { + if (val.lo == 0) + return (double)val.hi * shift64; + else + return -(double)(~val.lo + ~val.hi * shift64); + } + else + return (double)(val.lo + val.hi * shift64); + } + + //nb: Constructing two new Int128 objects every time we want to multiply longs + //is slow. So, although calling the Int128Mul method doesn't look as clean, the + //code runs significantly faster than if we'd used the * operator. + + public static Int128 Int128Mul(long lhs, long rhs) + { + bool negate = (lhs < 0) != (rhs < 0); + if (lhs < 0) lhs = -lhs; + if (rhs < 0) rhs = -rhs; + ulong int1Hi = (ulong)lhs >> 32; + ulong int1Lo = (ulong)lhs & 0xFFFFFFFF; + ulong int2Hi = (ulong)rhs >> 32; + ulong int2Lo = (ulong)rhs & 0xFFFFFFFF; + + //nb: see comments in clipper.pas + ulong a = int1Hi * int2Hi; + ulong b = int1Lo * int2Lo; + ulong c = int1Hi * int2Lo + int1Lo * int2Hi; + + ulong lo; + long hi; + hi = (long)(a + (c >> 32)); + + unchecked { lo = (c << 32) + b; } + if (lo < b) hi++; + Int128 result = new Int128(hi, lo); + return negate ? -result : result; + } + }; + + //------------------------------------------------------------------------------ + //------------------------------------------------------------------------------ + + internal struct IntPoint + { + public long X; + + public long Y; + + public IntPoint(long X, long Y) + { + this.X = X; this.Y = Y; + } + + public IntPoint(double x, double y) + { + this.X = (long)x; this.Y = (long)y; + } + + public IntPoint(IntPoint pt) + { + this.X = pt.X; this.Y = pt.Y; + } + + public static bool operator ==(IntPoint a, IntPoint b) + { + return a.X == b.X && a.Y == b.Y; + } + + public static bool operator !=(IntPoint a, IntPoint b) + { + return a.X != b.X || a.Y != b.Y; + } + + public override bool Equals(object obj) + { + if (obj == null) return false; + if (obj is IntPoint a) + { + return (X == a.X) && (Y == a.Y); + } + else return false; + } + + public override int GetHashCode() + { + //simply prevents a compiler warning + return base.GetHashCode(); + } + + }// end struct IntPoint + + internal struct IntRect + { + public long left; + + public long top; + + public long right; + + public long bottom; + + public IntRect(long l, long t, long r, long b) + { + this.left = l; this.top = t; + this.right = r; this.bottom = b; + } + + public IntRect(IntRect ir) + { + this.left = ir.left; this.top = ir.top; + this.right = ir.right; this.bottom = ir.bottom; + } + } + + internal enum ClipType + { + ctIntersection, + ctUnion, + ctDifference, + ctXor + }; + + + internal enum PolyType + { + ptSubject, + ptClip + }; + + /// + /// By far the most widely used winding rules for polygon filling are + /// EvenOdd and NonZero (GDI, GDI+, XLib, OpenGL, Cairo, AGG, Quartz, SVG, Gr32) + /// Others rules include Positive, Negative and ABS_GTR_EQ_TWO (only in OpenGL) + /// see http://glprogramming.com/red/chapter11.html + /// + internal enum PolyFillType + { + pftEvenOdd, + pftNonZero, + }; + + internal enum JoinType + { + jtSquare, + jtRound, + jtMiter + }; + + internal enum EndType + { + etClosedPolygon, + etClosedLine, + etOpenButt, + etOpenSquare, + etOpenRound + }; + + internal enum EdgeSide { esLeft, esRight }; + internal enum Direction { dRightToLeft, dLeftToRight }; + + internal class TEdge + { + internal IntPoint Bot; + internal IntPoint Curr; //current (updated for every new scanbeam) + internal IntPoint Top; + internal IntPoint Delta; + internal double Dx; + internal PolyType PolyTyp; + internal EdgeSide Side; //side only refers to current side of solution poly + internal int WindDelta; //1 or -1 depending on winding direction + internal int WindCnt; + internal int WindCnt2; //winding count of the opposite polytype + internal int OutIdx; + internal TEdge Next; + internal TEdge Prev; + internal TEdge NextInLML; + internal TEdge NextInAEL; + internal TEdge PrevInAEL; + internal TEdge NextInSEL; + internal TEdge PrevInSEL; + }; + + internal class IntersectNode + { + internal TEdge Edge1; + internal TEdge Edge2; + internal IntPoint Pt; + }; + + internal class MyIntersectNodeSort : IComparer + { + public int Compare(IntersectNode node1, IntersectNode node2) + { + long i = node2.Pt.Y - node1.Pt.Y; + if (i > 0) return 1; + else if (i < 0) return -1; + else return 0; + } + } + + internal class LocalMinima + { + internal long Y; + internal TEdge LeftBound; + internal TEdge RightBound; + internal LocalMinima Next; + }; + + internal class Scanbeam + { + internal long Y; + internal Scanbeam Next; + }; + + internal class Maxima + { + internal long X; + internal Maxima Next; + internal Maxima Prev; + }; + + /// + /// 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. + /// + internal class OutRec + { + internal int Idx; + internal bool IsHole; + internal bool IsOpen; + internal OutRec FirstLeft; //see comments in clipper.pas + internal OutPt Pts; + internal OutPt BottomPt; + internal PolyNode PolyNode; + }; + + internal class OutPt + { + internal int Idx; + internal IntPoint Pt; + internal OutPt Next; + internal OutPt Prev; + }; + + internal class Join + { + internal OutPt OutPt1; + internal OutPt OutPt2; + internal IntPoint OffPt; + }; + + internal class ClipperBase + { + internal const double horizontal = -3.4E+38; + internal const int Skip = -2; + internal const int Unassigned = -1; + internal const double tolerance = 1.0E-20; + internal static bool NearZero(double val) { return (val > -tolerance) && (val < tolerance); } + + public const long loRange = 0x3FFFFFFF; + + public const long hiRange = 0x3FFFFFFFFFFFFFFFL; + + internal LocalMinima m_MinimaList; + internal LocalMinima m_CurrentLM; + internal List> m_edges = new List>(); + internal Scanbeam m_Scanbeam; + internal List m_PolyOuts; + internal TEdge m_ActiveEdges; + internal bool m_UseFullRange; + internal bool m_HasOpenPaths; + + //------------------------------------------------------------------------------ + public bool PreserveCollinear + { + get; + set; + } + //------------------------------------------------------------------------------ + public void Swap(ref long val1, ref long val2) + { + long tmp = val1; + val1 = val2; + val2 = tmp; + } + //------------------------------------------------------------------------------ + + internal static bool IsHorizontal(TEdge e) + { + return e.Delta.Y == 0; + } + //------------------------------------------------------------------------------ + + internal bool PointIsVertex(IntPoint pt, OutPt pp) + { + OutPt pp2 = pp; + do + { + if (pp2.Pt == pt) return true; + pp2 = pp2.Next; + } + while (pp2 != pp); + return false; + } + //------------------------------------------------------------------------------ + + internal bool PointOnLineSegment(IntPoint pt, + IntPoint linePt1, IntPoint linePt2, bool UseFullRange) + { + if (UseFullRange) + return ((pt.X == linePt1.X) && (pt.Y == linePt1.Y)) || + ((pt.X == linePt2.X) && (pt.Y == linePt2.Y)) || + (((pt.X > linePt1.X) == (pt.X < linePt2.X)) && + ((pt.Y > linePt1.Y) == (pt.Y < linePt2.Y)) && + ((Int128.Int128Mul((pt.X - linePt1.X), (linePt2.Y - linePt1.Y)) == + Int128.Int128Mul((linePt2.X - linePt1.X), (pt.Y - linePt1.Y))))); + else + return ((pt.X == linePt1.X) && (pt.Y == linePt1.Y)) || + ((pt.X == linePt2.X) && (pt.Y == linePt2.Y)) || + (((pt.X > linePt1.X) == (pt.X < linePt2.X)) && + ((pt.Y > linePt1.Y) == (pt.Y < linePt2.Y)) && + ((pt.X - linePt1.X) * (linePt2.Y - linePt1.Y) == + (linePt2.X - linePt1.X) * (pt.Y - linePt1.Y))); + } + //------------------------------------------------------------------------------ + + internal bool PointOnPolygon(IntPoint pt, OutPt pp, bool UseFullRange) + { + OutPt pp2 = pp; + while (true) + { + if (PointOnLineSegment(pt, pp2.Pt, pp2.Next.Pt, UseFullRange)) + return true; + pp2 = pp2.Next; + if (pp2 == pp) break; + } + return false; + } + //------------------------------------------------------------------------------ + + internal static bool SlopesEqual(TEdge e1, TEdge e2, bool UseFullRange) + { + if (UseFullRange) + return Int128.Int128Mul(e1.Delta.Y, e2.Delta.X) == + Int128.Int128Mul(e1.Delta.X, e2.Delta.Y); + else return (long)(e1.Delta.Y) * (e2.Delta.X) == + (long)(e1.Delta.X) * (e2.Delta.Y); + } + //------------------------------------------------------------------------------ + + internal static bool SlopesEqual(IntPoint pt1, IntPoint pt2, + IntPoint pt3, bool UseFullRange) + { + if (UseFullRange) + return Int128.Int128Mul(pt1.Y - pt2.Y, pt2.X - pt3.X) == + Int128.Int128Mul(pt1.X - pt2.X, pt2.Y - pt3.Y); + else return + (pt1.Y - pt2.Y) * (pt2.X - pt3.X) - (pt1.X - pt2.X) * (pt2.Y - pt3.Y) == 0; + } + //------------------------------------------------------------------------------ + + internal static bool SlopesEqual(IntPoint pt1, IntPoint pt2, + IntPoint pt3, IntPoint pt4, bool UseFullRange) + { + if (UseFullRange) + return Int128.Int128Mul(pt1.Y - pt2.Y, pt3.X - pt4.X) == + Int128.Int128Mul(pt1.X - pt2.X, pt3.Y - pt4.Y); + else return + (pt1.Y - pt2.Y) * (pt3.X - pt4.X) - (pt1.X - pt2.X) * (pt3.Y - pt4.Y) == 0; + } + //------------------------------------------------------------------------------ + + internal ClipperBase() //constructor (nb: no external instantiation) + { + m_MinimaList = null; + m_CurrentLM = null; + m_UseFullRange = false; + m_HasOpenPaths = false; + } + //------------------------------------------------------------------------------ + + public virtual void Clear() + { + DisposeLocalMinimaList(); + for (int i = 0; i < m_edges.Count; ++i) + { + for (int j = 0; j < m_edges[i].Count; ++j) m_edges[i][j] = null; + m_edges[i].Clear(); + } + m_edges.Clear(); + m_UseFullRange = false; + m_HasOpenPaths = false; + } + //------------------------------------------------------------------------------ + + private void DisposeLocalMinimaList() + { + while (m_MinimaList != null) + { + LocalMinima tmpLm = m_MinimaList.Next; + m_MinimaList = null; + m_MinimaList = tmpLm; + } + m_CurrentLM = null; + } + //------------------------------------------------------------------------------ + + void RangeTest(IntPoint Pt, ref bool useFullRange) + { + if (useFullRange) + { + if (Pt.X > hiRange || Pt.Y > hiRange || -Pt.X > hiRange || -Pt.Y > hiRange) + throw new ClipperException("Coordinate outside allowed range"); + } + else if (Pt.X > loRange || Pt.Y > loRange || -Pt.X > loRange || -Pt.Y > loRange) + { + useFullRange = true; + RangeTest(Pt, ref useFullRange); + } + } + //------------------------------------------------------------------------------ + + private void InitEdge(TEdge e, TEdge eNext, + TEdge ePrev, IntPoint pt) + { + e.Next = eNext; + e.Prev = ePrev; + e.Curr = pt; + e.OutIdx = Unassigned; + } + //------------------------------------------------------------------------------ + + private void InitEdge2(TEdge e, PolyType polyType) + { + 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 = polyType; + } + //------------------------------------------------------------------------------ + + private TEdge FindNextLocMin(TEdge E) + { + TEdge E2; + for (; ; ) + { + while (E.Bot != E.Prev.Bot || E.Curr == E.Top) E = E.Next; + if (E.Dx != horizontal && E.Prev.Dx != horizontal) break; + while (E.Prev.Dx == horizontal) E = E.Prev; + E2 = E; + while (E.Dx == horizontal) 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; + } + //------------------------------------------------------------------------------ + + private TEdge ProcessBound(TEdge E, bool LeftBoundIsForward) + { + TEdge EStart, Result = E; + TEdge Horz; + + if (Result.OutIdx == Skip) + { + //check if there are edges beyond the skip edge in the bound and if so + //create another LocMin and calling ProcessBound once more ... + E = Result; + if (LeftBoundIsForward) + { + while (E.Top.Y == E.Next.Bot.Y) E = E.Next; + while (E != Result && E.Dx == horizontal) E = E.Prev; + } + else + { + while (E.Top.Y == E.Prev.Bot.Y) E = E.Prev; + while (E != Result && E.Dx == horizontal) E = E.Next; + } + if (E == Result) + { + if (LeftBoundIsForward) Result = E.Next; + else Result = E.Prev; + } + else + { + //there are more edges in the bound beyond result starting with E + if (LeftBoundIsForward) + E = Result.Next; + else + E = Result.Prev; + LocalMinima locMin = new LocalMinima + { + Next = null, + Y = E.Bot.Y, + LeftBound = null, + RightBound = E + }; + E.WindDelta = 0; + Result = ProcessBound(E, LeftBoundIsForward); + InsertLocalMinima(locMin); + } + return Result; + } + + if (E.Dx == horizontal) + { + //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 (LeftBoundIsForward) EStart = E.Prev; + else EStart = E.Next; + if (EStart.Dx == horizontal) //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 (LeftBoundIsForward) + { + while (Result.Top.Y == Result.Next.Bot.Y && Result.Next.OutIdx != Skip) + Result = Result.Next; + if (Result.Dx == horizontal && 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 (Horz.Prev.Dx == horizontal) Horz = Horz.Prev; + if (Horz.Prev.Top.X > Result.Next.Top.X) Result = Horz.Prev; + } + while (E != Result) + { + E.NextInLML = E.Next; + if (E.Dx == horizontal && E != EStart && E.Bot.X != E.Prev.Top.X) + ReverseHorizontal(E); + E = E.Next; + } + if (E.Dx == horizontal && 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 (Result.Dx == horizontal && Result.Prev.OutIdx != Skip) + { + Horz = Result; + while (Horz.Next.Dx == horizontal) 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 (E.Dx == horizontal && E != EStart && E.Bot.X != E.Next.Top.X) + ReverseHorizontal(E); + E = E.Prev; + } + if (E.Dx == horizontal && E != EStart && E.Bot.X != E.Next.Top.X) + ReverseHorizontal(E); + Result = Result.Prev; //move to the edge just beyond current bound + } + return Result; + } + //------------------------------------------------------------------------------ + + public bool AddPath(List pg, PolyType polyType, bool Closed) + { + if (!Closed && polyType == PolyType.ptClip) + throw new ClipperException("AddPath: Open paths must be subject."); + + int highI = (int)pg.Count - 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 ... + List edges = new List(highI + 1); + for (int i = 0; i <= highI; i++) edges.Add(new TEdge()); + + bool IsFlat = true; + + //1. Basic (first) edge initialization ... + edges[1].Curr = pg[1]; + RangeTest(pg[0], ref m_UseFullRange); + RangeTest(pg[highI], ref 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], ref m_UseFullRange); + InitEdge(edges[i], edges[i + 1], edges[i - 1], pg[i]); + } + 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) && + (!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))) + return false; + + if (!Closed) + { + m_HasOpenPaths = true; + eStart.Prev.OutIdx = Skip; + } + + //3. Do second stage of edge initialization ... + E = eStart; + do + { + InitEdge2(E, polyType); + 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) return false; + E.Prev.OutIdx = Skip; + LocalMinima locMin = new LocalMinima + { + Next = null, + Y = E.Bot.Y, + LeftBound = null, + RightBound = E + }; + locMin.RightBound.Side = EdgeSide.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; + } + InsertLocalMinima(locMin); + m_edges.Add(edges); + return true; + } + + m_edges.Add(edges); + bool leftBoundIsForward; + TEdge EMin = null; + + //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 == null) EMin = E; + + //E and E.Prev now share a local minima (left aligned if horizontal). + //Compare their slopes to find which starts which bound ... + LocalMinima locMin = new LocalMinima + { + Next = null, + 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 + } + locMin.LeftBound.Side = EdgeSide.esLeft; + locMin.RightBound.Side = EdgeSide.esRight; + + 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 = null; + else if (locMin.RightBound.OutIdx == Skip) + locMin.RightBound = null; + InsertLocalMinima(locMin); + if (!leftBoundIsForward) E = E2; + } + return true; + + } + //------------------------------------------------------------------------------ + + public bool AddPaths(List> ppg, PolyType polyType, bool closed) + { + bool result = false; + for (int i = 0; i < ppg.Count; ++i) + if (AddPath(ppg[i], polyType, closed)) result = true; + return result; + } + //------------------------------------------------------------------------------ + + internal bool Pt2IsBetweenPt1AndPt3(IntPoint pt1, IntPoint pt2, 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); + } + //------------------------------------------------------------------------------ + + 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 = null; //flag as removed (see ClipperBase.Clear) + return result; + } + //------------------------------------------------------------------------------ + + private void SetDx(TEdge e) + { + e.Delta.X = (e.Top.X - e.Bot.X); + e.Delta.Y = (e.Top.Y - e.Bot.Y); + if (e.Delta.Y == 0) e.Dx = horizontal; + else e.Dx = (double)(e.Delta.X) / (e.Delta.Y); + } + //--------------------------------------------------------------------------- + + private void InsertLocalMinima(LocalMinima newLm) + { + if (m_MinimaList == null) + { + m_MinimaList = newLm; + } + else if (newLm.Y >= m_MinimaList.Y) + { + newLm.Next = m_MinimaList; + m_MinimaList = newLm; + } + else + { + LocalMinima tmpLm = m_MinimaList; + while (tmpLm.Next != null && (newLm.Y < tmpLm.Next.Y)) + tmpLm = tmpLm.Next; + newLm.Next = tmpLm.Next; + tmpLm.Next = newLm; + } + } + //------------------------------------------------------------------------------ + + internal bool PopLocalMinima(long Y, out LocalMinima current) + { + current = m_CurrentLM; + if (m_CurrentLM != null && m_CurrentLM.Y == Y) + { + m_CurrentLM = m_CurrentLM.Next; + return true; + } + return false; + } + //------------------------------------------------------------------------------ + + private 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.] + Swap(ref e.Top.X, ref e.Bot.X); + } + //------------------------------------------------------------------------------ + + internal virtual void Reset() + { + m_CurrentLM = m_MinimaList; + if (m_CurrentLM == null) return; //ie nothing to process + + //reset all edges ... + m_Scanbeam = null; + LocalMinima lm = m_MinimaList; + while (lm != null) + { + InsertScanbeam(lm.Y); + TEdge e = lm.LeftBound; + if (e != null) + { + e.Curr = e.Bot; + e.OutIdx = Unassigned; + } + e = lm.RightBound; + if (e != null) + { + e.Curr = e.Bot; + e.OutIdx = Unassigned; + } + lm = lm.Next; + } + m_ActiveEdges = null; + } + //------------------------------------------------------------------------------ + + public static IntRect GetBounds(List> paths) + { + int i = 0, cnt = paths.Count; + while (i < cnt && paths[i].Count == 0) i++; + if (i == cnt) return new IntRect(0, 0, 0, 0); + IntRect result = new IntRect + { + left = paths[i][0].X + }; + result.right = result.left; + result.top = paths[i][0].Y; + result.bottom = result.top; + for (; i < cnt; i++) + for (int j = 0; j < paths[i].Count; j++) + { + if (paths[i][j].X < result.left) result.left = paths[i][j].X; + else if (paths[i][j].X > result.right) result.right = paths[i][j].X; + if (paths[i][j].Y < result.top) result.top = paths[i][j].Y; + else if (paths[i][j].Y > result.bottom) result.bottom = paths[i][j].Y; + } + return result; + } + //------------------------------------------------------------------------------ + + internal void InsertScanbeam(long Y) + { + //single-linked list: sorted descending, ignoring dups. + if (m_Scanbeam == null) + { + m_Scanbeam = new Scanbeam + { + Next = null, + Y = Y + }; + } + else if (Y > m_Scanbeam.Y) + { + Scanbeam newSb = new Scanbeam + { + Y = Y, + Next = m_Scanbeam + }; + m_Scanbeam = newSb; + } + else + { + Scanbeam sb2 = m_Scanbeam; + while (sb2.Next != null && (Y <= sb2.Next.Y)) sb2 = sb2.Next; + if (Y == sb2.Y) return; //ie ignores duplicates + Scanbeam newSb = new Scanbeam + { + Y = Y, + Next = sb2.Next + }; + sb2.Next = newSb; + } + } + //------------------------------------------------------------------------------ + + internal bool PopScanbeam(out long Y) + { + if (m_Scanbeam == null) + { + Y = 0; + return false; + } + Y = m_Scanbeam.Y; + m_Scanbeam = m_Scanbeam.Next; + return true; + } + //------------------------------------------------------------------------------ + + internal bool LocalMinimaPending() + { + return (m_CurrentLM != null); + } + //------------------------------------------------------------------------------ + + internal OutRec CreateOutRec() + { + OutRec result = new OutRec + { + Idx = Unassigned, + IsHole = false, + IsOpen = false, + FirstLeft = null, + Pts = null, + BottomPt = null, + PolyNode = null + }; + m_PolyOuts.Add(result); + result.Idx = m_PolyOuts.Count - 1; + return result; + } + //------------------------------------------------------------------------------ + + internal void DisposeOutRec(int index) + { + OutRec outRec = m_PolyOuts[index]; + outRec.Pts = null; + outRec = null; + m_PolyOuts[index] = null; + } + //------------------------------------------------------------------------------ + + internal void UpdateEdgeIntoAEL(ref TEdge e) + { + if (e.NextInLML == null) + throw new ClipperException("UpdateEdgeIntoAEL: invalid call"); + TEdge AelPrev = e.PrevInAEL; + TEdge AelNext = e.NextInAEL; + e.NextInLML.OutIdx = e.OutIdx; + if (AelPrev != null) + AelPrev.NextInAEL = e.NextInLML; + else m_ActiveEdges = e.NextInLML; + if (AelNext != null) + 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); + } + //------------------------------------------------------------------------------ + + internal void 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 != null) + next.PrevInAEL = edge1; + TEdge prev = edge1.PrevInAEL; + if (prev != null) + 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 != null) + next.PrevInAEL = edge2; + TEdge prev = edge2.PrevInAEL; + if (prev != null) + 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 != null) + edge1.NextInAEL.PrevInAEL = edge1; + edge1.PrevInAEL = edge2.PrevInAEL; + if (edge1.PrevInAEL != null) + edge1.PrevInAEL.NextInAEL = edge1; + edge2.NextInAEL = next; + if (edge2.NextInAEL != null) + edge2.NextInAEL.PrevInAEL = edge2; + edge2.PrevInAEL = prev; + if (edge2.PrevInAEL != null) + edge2.PrevInAEL.NextInAEL = edge2; + } + + if (edge1.PrevInAEL == null) + m_ActiveEdges = edge1; + else if (edge2.PrevInAEL == null) + m_ActiveEdges = edge2; + } + //------------------------------------------------------------------------------ + + internal void DeleteFromAEL(TEdge e) + { + TEdge AelPrev = e.PrevInAEL; + TEdge AelNext = e.NextInAEL; + if (AelPrev == null && AelNext == null && (e != m_ActiveEdges)) + return; //already deleted + if (AelPrev != null) + AelPrev.NextInAEL = AelNext; + else m_ActiveEdges = AelNext; + if (AelNext != null) + AelNext.PrevInAEL = AelPrev; + e.NextInAEL = null; + e.PrevInAEL = null; + } + //------------------------------------------------------------------------------ + + } //end ClipperBase + + internal class Clipper : ClipperBase + { + //InitOptions that can be passed to the constructor ... + public const int ioReverseSolution = 1; + + public const int ioStrictlySimple = 2; + + public const int ioPreserveCollinear = 4; + + private ClipType m_ClipType; + private Maxima m_Maxima; + private TEdge m_SortedEdges; + private readonly List m_IntersectList; + readonly IComparer m_IntersectNodeComparer; + private bool m_ExecuteLocked; + private PolyFillType m_ClipFillType; + private PolyFillType m_SubjFillType; + private readonly List m_Joins; + private readonly List m_GhostJoins; + private bool m_UsingPolyTree; + + public Clipper(int InitOptions = 0) : base() //constructor + { + m_Scanbeam = null; + m_Maxima = null; + m_ActiveEdges = null; + m_SortedEdges = null; + m_IntersectList = new List(); + m_IntersectNodeComparer = new MyIntersectNodeSort(); + m_ExecuteLocked = false; + m_UsingPolyTree = false; + m_PolyOuts = new List(); + m_Joins = new List(); + m_GhostJoins = new List(); + ReverseSolution = (ioReverseSolution & InitOptions) != 0; + StrictlySimple = (ioStrictlySimple & InitOptions) != 0; + PreserveCollinear = (ioPreserveCollinear & InitOptions) != 0; + } + //------------------------------------------------------------------------------ + + private void InsertMaxima(long X) + { + //double-linked list: sorted ascending, ignoring dups. + Maxima newMax = new Maxima + { + X = X + }; + if (m_Maxima == null) + { + m_Maxima = newMax; + m_Maxima.Next = null; + m_Maxima.Prev = null; + } + else if (X < m_Maxima.X) + { + newMax.Next = m_Maxima; + newMax.Prev = null; + m_Maxima = newMax; + } + else + { + Maxima m = m_Maxima; + while (m.Next != null && (X >= m.Next.X)) m = m.Next; + if (X == m.X) return; //ie ignores duplicates (& CG to clean up newMax) + //insert newMax between m and m.Next ... + newMax.Next = m.Next; + newMax.Prev = m; + if (m.Next != null) m.Next.Prev = newMax; + m.Next = newMax; + } + } + //------------------------------------------------------------------------------ + + public bool ReverseSolution + { + get; + set; + } + //------------------------------------------------------------------------------ + + public bool StrictlySimple + { + get; + set; + } + //------------------------------------------------------------------------------ + + public bool Execute(ClipType clipType, List> solution, + PolyFillType FillType = PolyFillType.pftEvenOdd) + { + return Execute(clipType, solution, FillType, FillType); + } + //------------------------------------------------------------------------------ + + public bool Execute(ClipType clipType, PolyTree polytree, + PolyFillType FillType = PolyFillType.pftEvenOdd) + { + return Execute(clipType, polytree, FillType, FillType); + } + //------------------------------------------------------------------------------ + + public bool Execute(ClipType clipType, List> solution, + PolyFillType subjFillType, PolyFillType clipFillType) + { + if (m_ExecuteLocked) return false; + if (m_HasOpenPaths) throw + new ClipperException("Error: PolyTree struct is needed for open path clipping."); + + m_ExecuteLocked = true; + solution.Clear(); + m_SubjFillType = subjFillType; + m_ClipFillType = clipFillType; + m_ClipType = clipType; + m_UsingPolyTree = false; + bool succeeded; + try + { + succeeded = ExecuteInternal(); + //build the return polygons ... + if (succeeded) BuildResult(solution); + } + finally + { + DisposeAllPolyPts(); + m_ExecuteLocked = false; + } + return succeeded; + } + //------------------------------------------------------------------------------ + + public bool 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; + try + { + succeeded = ExecuteInternal(); + //build the return polygons ... + if (succeeded) BuildResult2(polytree); + } + finally + { + DisposeAllPolyPts(); + m_ExecuteLocked = false; + } + return succeeded; + } + //------------------------------------------------------------------------------ + + internal void FixHoleLinkage(OutRec outRec) + { + //skip if an outermost polygon or + //already already points to the correct FirstLeft ... + if (outRec.FirstLeft == null || + (outRec.IsHole != outRec.FirstLeft.IsHole && + outRec.FirstLeft.Pts != null)) return; + + OutRec orfl = outRec.FirstLeft; + while (orfl != null && ((orfl.IsHole == outRec.IsHole) || orfl.Pts == null)) + orfl = orfl.FirstLeft; + outRec.FirstLeft = orfl; + } + //------------------------------------------------------------------------------ + + private bool ExecuteInternal() + { + try + { + Reset(); + m_SortedEdges = null; + m_Maxima = null; + + if (!PopScanbeam(out long botY)) return false; + InsertLocalMinimaIntoAEL(botY); + while (PopScanbeam(out long topY) || LocalMinimaPending()) + { + ProcessHorizontals(); + m_GhostJoins.Clear(); + if (!ProcessIntersections(topY)) return false; + ProcessEdgesAtTopOfScanbeam(topY); + botY = topY; + InsertLocalMinimaIntoAEL(botY); + } + + //fix orientations ... + foreach (OutRec outRec in m_PolyOuts) + { + if (outRec.Pts == null || outRec.IsOpen) continue; + if ((outRec.IsHole ^ ReverseSolution) == (Area(outRec) > 0)) + ReversePolyPtLinks(outRec.Pts); + } + + JoinCommonEdges(); + + foreach (OutRec outRec in m_PolyOuts) + { + if (outRec.Pts == null) + continue; + else if (outRec.IsOpen) + FixupOutPolyline(outRec); + else + FixupOutPolygon(outRec); + } + + if (StrictlySimple) DoSimplePolygons(); + return true; + } + //catch { return false; } + finally + { + m_Joins.Clear(); + m_GhostJoins.Clear(); + } + } + //------------------------------------------------------------------------------ + + private void DisposeAllPolyPts() + { + for (int i = 0; i < m_PolyOuts.Count; ++i) DisposeOutRec(i); + m_PolyOuts.Clear(); + } + //------------------------------------------------------------------------------ + + private void AddJoin(OutPt Op1, OutPt Op2, IntPoint OffPt) + { + Join j = new Join + { + OutPt1 = Op1, + OutPt2 = Op2, + OffPt = OffPt + }; + m_Joins.Add(j); + } + //------------------------------------------------------------------------------ + + private void AddGhostJoin(OutPt Op, IntPoint OffPt) + { + Join j = new Join + { + OutPt1 = Op, + OffPt = OffPt + }; + m_GhostJoins.Add(j); + } + //------------------------------------------------------------------------------ + + private void InsertLocalMinimaIntoAEL(long botY) + { + while (PopLocalMinima(botY, out LocalMinima lm)) + { + TEdge lb = lm.LeftBound; + TEdge rb = lm.RightBound; + + OutPt Op1 = null; + if (lb == null) + { + InsertEdgeIntoAEL(rb, null); + SetWindingCount(rb); + if (IsContributing(rb)) + Op1 = AddOutPt(rb, rb.Bot); + } + else if (rb == null) + { + InsertEdgeIntoAEL(lb, null); + SetWindingCount(lb); + if (IsContributing(lb)) + Op1 = AddOutPt(lb, lb.Bot); + InsertScanbeam(lb.Top.Y); + } + else + { + InsertEdgeIntoAEL(lb, null); + 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 != null) + { + if (IsHorizontal(rb)) + { + if (rb.NextInLML != null) + InsertScanbeam(rb.NextInLML.Top.Y); + AddEdgeToSEL(rb); + } + else + InsertScanbeam(rb.Top.Y); + } + + if (lb == null || rb == null) continue; + + //if output polygons share an Edge with a horizontal rb, they'll need joining later ... + if (Op1 != null && IsHorizontal(rb) && + m_GhostJoins.Count > 0 && rb.WindDelta != 0) + { + for (int i = 0; i < m_GhostJoins.Count; i++) + { + //if the horizontal Rb and a 'ghost' horizontal overlap, then convert + //the 'ghost' join to a real join ready for later ... + Join j = m_GhostJoins[i]; + if (HorzSegmentsOverlap(j.OutPt1.Pt.X, j.OffPt.X, rb.Bot.X, rb.Top.X)) + AddJoin(j.OutPt1, Op1, j.OffPt); + } + } + + if (lb.OutIdx >= 0 && lb.PrevInAEL != null && + lb.PrevInAEL.Curr.X == lb.Bot.X && + lb.PrevInAEL.OutIdx >= 0 && + SlopesEqual(lb.PrevInAEL.Curr, 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 != null) + 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; + } + } + } + } + //------------------------------------------------------------------------------ + + private void InsertEdgeIntoAEL(TEdge edge, TEdge startEdge) + { + if (m_ActiveEdges == null) + { + edge.PrevInAEL = null; + edge.NextInAEL = null; + m_ActiveEdges = edge; + } + else if (startEdge == null && E2InsertsBeforeE1(m_ActiveEdges, edge)) + { + edge.PrevInAEL = null; + edge.NextInAEL = m_ActiveEdges; + m_ActiveEdges.PrevInAEL = edge; + m_ActiveEdges = edge; + } + else + { + if (startEdge == null) startEdge = m_ActiveEdges; + while (startEdge.NextInAEL != null && + !E2InsertsBeforeE1(startEdge.NextInAEL, edge)) + startEdge = startEdge.NextInAEL; + edge.NextInAEL = startEdge.NextInAEL; + if (startEdge.NextInAEL != null) startEdge.NextInAEL.PrevInAEL = edge; + edge.PrevInAEL = startEdge; + startEdge.NextInAEL = edge; + } + } + //---------------------------------------------------------------------- + + private 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; + } + //------------------------------------------------------------------------------ + + private bool IsEvenOddFillType(TEdge edge) + { + if (edge.PolyTyp == PolyType.ptSubject) + return m_SubjFillType == PolyFillType.pftEvenOdd; + else + return m_ClipFillType == PolyFillType.pftEvenOdd; + } + //------------------------------------------------------------------------------ + + private bool IsEvenOddAltFillType(TEdge edge) + { + if (edge.PolyTyp == PolyType.ptSubject) + return m_ClipFillType == PolyFillType.pftEvenOdd; + else + return m_SubjFillType == PolyFillType.pftEvenOdd; + } + //------------------------------------------------------------------------------ + + private bool IsContributing(TEdge edge) + { + PolyFillType pft, pft2; + if (edge.PolyTyp == PolyType.ptSubject) + { + pft = m_SubjFillType; + pft2 = m_ClipFillType; + } + else + { + pft = m_ClipFillType; + pft2 = m_SubjFillType; + } + + switch (pft) + { + default: + case PolyFillType.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 PolyFillType.pftNonZero: + if (Math.Abs(edge.WindCnt) != 1) return false; + break; + } + + switch (m_ClipType) + { + case ClipType.ctIntersection: + return (edge.WindCnt2 != 0); + case ClipType.ctUnion: + return (edge.WindCnt2 == 0); + case ClipType.ctDifference: + if (edge.PolyTyp == PolyType.ptSubject) + return (edge.WindCnt2 == 0); + else + return (edge.WindCnt2 != 0); + case ClipType.ctXor: + if (edge.WindDelta == 0) //XOr always contributing unless open + return (edge.WindCnt2 == 0); + else + return true; + } + return true; + } + //------------------------------------------------------------------------------ + + private void SetWindingCount(TEdge edge) + { + TEdge e = edge.PrevInAEL; + //find the edge of the same polytype that immediately preceeds 'edge' in AEL + while (e != null && ((e.PolyTyp != edge.PolyTyp) || (e.WindDelta == 0))) e = e.PrevInAEL; + if (e == null) + { + PolyFillType pft = (edge.PolyTyp == PolyType.ptSubject ? m_SubjFillType : m_ClipFillType); + if (edge.WindDelta == 0) edge.WindCnt = 1; // (pft == PolyFillType.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 != 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 != null) + { + 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 (Math.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; + } + } + } + //------------------------------------------------------------------------------ + + private void AddEdgeToSEL(TEdge edge) + { + //SEL pointers in PEdge are use to build transient lists of horizontal edges. + //However, since we don't need to worry about processing order, all additions + //are made to the front of the list ... + if (m_SortedEdges == null) + { + m_SortedEdges = edge; + edge.PrevInSEL = null; + edge.NextInSEL = null; + } + else + { + edge.NextInSEL = m_SortedEdges; + edge.PrevInSEL = null; + m_SortedEdges.PrevInSEL = edge; + m_SortedEdges = edge; + } + } + //------------------------------------------------------------------------------ + + internal bool PopEdgeFromSEL(out TEdge e) + { + //Pop edge from front of SEL (ie SEL is a FILO list) + e = m_SortedEdges; + if (e == null) return false; + TEdge oldE = e; + m_SortedEdges = e.NextInSEL; + if (m_SortedEdges != null) m_SortedEdges.PrevInSEL = null; + oldE.NextInSEL = null; + oldE.PrevInSEL = null; + return true; + } + //------------------------------------------------------------------------------ + + private void CopyAELToSEL() + { + TEdge e = m_ActiveEdges; + m_SortedEdges = e; + while (e != null) + { + e.PrevInSEL = e.PrevInAEL; + e.NextInSEL = e.NextInAEL; + e = e.NextInAEL; + } + } + //------------------------------------------------------------------------------ + + private void SwapPositionsInSEL(TEdge edge1, TEdge edge2) + { + if (edge1.NextInSEL == null && edge1.PrevInSEL == null) + return; + if (edge2.NextInSEL == null && edge2.PrevInSEL == null) + return; + + if (edge1.NextInSEL == edge2) + { + TEdge next = edge2.NextInSEL; + if (next != null) + next.PrevInSEL = edge1; + TEdge prev = edge1.PrevInSEL; + if (prev != null) + 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 != null) + next.PrevInSEL = edge2; + TEdge prev = edge2.PrevInSEL; + if (prev != null) + 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 != null) + edge1.NextInSEL.PrevInSEL = edge1; + edge1.PrevInSEL = edge2.PrevInSEL; + if (edge1.PrevInSEL != null) + edge1.PrevInSEL.NextInSEL = edge1; + edge2.NextInSEL = next; + if (edge2.NextInSEL != null) + edge2.NextInSEL.PrevInSEL = edge2; + edge2.PrevInSEL = prev; + if (edge2.PrevInSEL != null) + edge2.PrevInSEL.NextInSEL = edge2; + } + + if (edge1.PrevInSEL == null) + m_SortedEdges = edge1; + else if (edge2.PrevInSEL == null) + m_SortedEdges = edge2; + } + //------------------------------------------------------------------------------ + + + private void AddLocalMaxPoly(TEdge e1, TEdge e2, 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); + } + //------------------------------------------------------------------------------ + + private OutPt AddLocalMinPoly(TEdge e1, TEdge e2, IntPoint pt) + { + OutPt result; + TEdge e, prevE; + if (IsHorizontal(e2) || (e1.Dx > e2.Dx)) + { + result = AddOutPt(e1, pt); + e2.OutIdx = e1.OutIdx; + e1.Side = EdgeSide.esLeft; + e2.Side = EdgeSide.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 = EdgeSide.esRight; + e2.Side = EdgeSide.esLeft; + e = e2; + if (e.PrevInAEL == e1) + prevE = e1.PrevInAEL; + else + prevE = e.PrevInAEL; + } + + if (prevE != null && prevE.OutIdx >= 0 && prevE.Top.Y < pt.Y && e.Top.Y < pt.Y) + { + long xPrev = TopX(prevE, pt.Y); + long xE = TopX(e, pt.Y); + if ((xPrev == xE) && (e.WindDelta != 0) && (prevE.WindDelta != 0) && + SlopesEqual(new IntPoint(xPrev, pt.Y), prevE.Top, new IntPoint(xE, pt.Y), e.Top, m_UseFullRange)) + { + OutPt outPt = AddOutPt(prevE, pt); + AddJoin(result, outPt, e.Top); + } + } + return result; + } + //------------------------------------------------------------------------------ + + private OutPt AddOutPt(TEdge e, 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; //nb: do this after SetZ ! + 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 == EdgeSide.esLeft); + if (ToFront && pt == op.Pt) return op; + else if (!ToFront && pt == op.Prev.Pt) return op.Prev; + + OutPt newOp = new OutPt + { + Idx = outRec.Idx, + Pt = pt, + Next = op, + Prev = op.Prev + }; + newOp.Prev.Next = newOp; + op.Prev = newOp; + if (ToFront) outRec.Pts = newOp; + return newOp; + } + } + //------------------------------------------------------------------------------ + + private OutPt GetLastOutPt(TEdge e) + { + OutRec outRec = m_PolyOuts[e.OutIdx]; + if (e.Side == EdgeSide.esLeft) + return outRec.Pts; + else + return outRec.Pts.Prev; + } + //------------------------------------------------------------------------------ + + internal void SwapPoints(ref IntPoint pt1, ref IntPoint pt2) + { + IntPoint tmp = new IntPoint(pt1); + pt1 = pt2; + pt2 = tmp; + } + //------------------------------------------------------------------------------ + + private bool HorzSegmentsOverlap(long seg1a, long seg1b, long seg2a, long seg2b) + { + if (seg1a > seg1b) Swap(ref seg1a, ref seg1b); + if (seg2a > seg2b) Swap(ref seg2a, ref seg2b); + return (seg1a < seg2b) && (seg2a < seg1b); + } + //------------------------------------------------------------------------------ + + private void SetHoleState(TEdge e, OutRec outRec) + { + TEdge e2 = e.PrevInAEL; + TEdge eTmp = null; + while (e2 != null) + { + if (e2.OutIdx >= 0 && e2.WindDelta != 0) + { + if (eTmp == null) + eTmp = e2; + else if (eTmp.OutIdx == e2.OutIdx) + eTmp = null; //paired + } + e2 = e2.PrevInAEL; + } + + if (eTmp == null) + { + outRec.FirstLeft = null; + outRec.IsHole = false; + } + else + { + outRec.FirstLeft = m_PolyOuts[eTmp.OutIdx]; + outRec.IsHole = !outRec.FirstLeft.IsHole; + } + } + //------------------------------------------------------------------------------ + + private double GetDx(IntPoint pt1, IntPoint pt2) + { + if (pt1.Y == pt2.Y) return horizontal; + else return (double)(pt2.X - pt1.X) / (pt2.Y - pt1.Y); + } + //--------------------------------------------------------------------------- + + private bool FirstIsBottomPt(OutPt btmPt1, OutPt btmPt2) + { + OutPt p = btmPt1.Prev; + while ((p.Pt == btmPt1.Pt) && (p != btmPt1)) p = p.Prev; + double dx1p = Math.Abs(GetDx(btmPt1.Pt, p.Pt)); + p = btmPt1.Next; + while ((p.Pt == btmPt1.Pt) && (p != btmPt1)) p = p.Next; + double dx1n = Math.Abs(GetDx(btmPt1.Pt, p.Pt)); + + p = btmPt2.Prev; + while ((p.Pt == btmPt2.Pt) && (p != btmPt2)) p = p.Prev; + double dx2p = Math.Abs(GetDx(btmPt2.Pt, p.Pt)); + p = btmPt2.Next; + while ((p.Pt == btmPt2.Pt) && (p != btmPt2)) p = p.Next; + double dx2n = Math.Abs(GetDx(btmPt2.Pt, p.Pt)); + + if (Math.Max(dx1p, dx1n) == Math.Max(dx2p, dx2n) && + Math.Min(dx1p, dx1n) == Math.Min(dx2p, dx2n)) + return Area(btmPt1) > 0; //if otherwise identical use orientation + else + return (dx1p >= dx2p && dx1p >= dx2n) || (dx1n >= dx2p && dx1n >= dx2n); + } + //------------------------------------------------------------------------------ + + private OutPt GetBottomPt(OutPt pp) + { + OutPt dups = null; + OutPt p = pp.Next; + while (p != pp) + { + if (p.Pt.Y > pp.Pt.Y) + { + pp = p; + dups = null; + } + else if (p.Pt.Y == pp.Pt.Y && p.Pt.X <= pp.Pt.X) + { + if (p.Pt.X < pp.Pt.X) + { + dups = null; + pp = p; + } + else + { + if (p.Next != pp && p.Prev != pp) dups = p; + } + } + p = p.Next; + } + if (dups != null) + { + //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; + } + //------------------------------------------------------------------------------ + + private OutRec GetLowermostRec(OutRec outRec1, OutRec outRec2) + { + //work out which polygon fragment has the correct hole state ... + if (outRec1.BottomPt == null) + outRec1.BottomPt = GetBottomPt(outRec1.Pts); + if (outRec2.BottomPt == null) + outRec2.BottomPt = GetBottomPt(outRec2.Pts); + OutPt bPt1 = outRec1.BottomPt; + OutPt bPt2 = outRec2.BottomPt; + if (bPt1.Pt.Y > bPt2.Pt.Y) return outRec1; + else if (bPt1.Pt.Y < bPt2.Pt.Y) return outRec2; + else if (bPt1.Pt.X < bPt2.Pt.X) return outRec1; + else if (bPt1.Pt.X > bPt2.Pt.X) return outRec2; + else if (bPt1.Next == bPt1) return outRec2; + else if (bPt2.Next == bPt2) return outRec1; + else if (FirstIsBottomPt(bPt1, bPt2)) return outRec1; + else return outRec2; + } + //------------------------------------------------------------------------------ + + bool OutRec1RightOfOutRec2(OutRec outRec1, OutRec outRec2) + { + do + { + outRec1 = outRec1.FirstLeft; + if (outRec1 == outRec2) return true; + } while (outRec1 != null); + return false; + } + //------------------------------------------------------------------------------ + + private OutRec GetOutRec(int idx) + { + OutRec outrec = m_PolyOuts[idx]; + while (outrec != m_PolyOuts[outrec.Idx]) + outrec = m_PolyOuts[outrec.Idx]; + return outrec; + } + //------------------------------------------------------------------------------ + + private void AppendPolygon(TEdge e1, TEdge e2) + { + 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 == EdgeSide.esLeft) + { + if (e2.Side == EdgeSide.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 == EdgeSide.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 = null; + if (holeStateRec == outRec2) + { + if (outRec2.FirstLeft != outRec1) + outRec1.FirstLeft = outRec2.FirstLeft; + outRec1.IsHole = outRec2.IsHole; + } + outRec2.Pts = null; + outRec2.BottomPt = null; + + 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 != null) + { + if (e.OutIdx == ObsoleteIdx) + { + e.OutIdx = OKIdx; + e.Side = e1.Side; + break; + } + e = e.NextInAEL; + } + outRec2.Idx = outRec1.Idx; + } + //------------------------------------------------------------------------------ + + private void ReversePolyPtLinks(OutPt pp) + { + if (pp == null) return; + OutPt pp1; + OutPt pp2; + pp1 = pp; + do + { + pp2 = pp1.Next; + pp1.Next = pp1.Prev; + pp1.Prev = pp2; + pp1 = pp2; + } while (pp1 != pp); + } + //------------------------------------------------------------------------------ + + private static void SwapSides(TEdge edge1, TEdge edge2) + { + EdgeSide side = edge1.Side; + edge1.Side = edge2.Side; + edge2.Side = side; + } + //------------------------------------------------------------------------------ + + private static void SwapPolyIndexes(TEdge edge1, TEdge edge2) + { + int outIdx = edge1.OutIdx; + edge1.OutIdx = edge2.OutIdx; + edge2.OutIdx = outIdx; + } + //------------------------------------------------------------------------------ + + private void IntersectEdges(TEdge e1, TEdge e2, IntPoint pt) + { + //e1 will be to the left of e2 BELOW the intersection. Therefore e1 is before + //e2 in AEL except when e1 is being inserted at the intersection point ... + + bool e1Contributing = (e1.OutIdx >= 0); + bool e2Contributing = (e2.OutIdx >= 0); + + // use_lines start + //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 == 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) + { + if ((e1.WindDelta == 0) && Math.Abs(e2.WindCnt) == 1 && + (m_ClipType != ClipType.ctUnion || e2.WindCnt2 == 0)) + { + AddOutPt(e1, pt); + if (e1Contributing) e1.OutIdx = Unassigned; + } + else if ((e2.WindDelta == 0) && (Math.Abs(e1.WindCnt) == 1) && + (m_ClipType != ClipType.ctUnion || e1.WindCnt2 == 0)) + { + AddOutPt(e2, pt); + if (e2Contributing) e2.OutIdx = Unassigned; + } + } + return; + } + // use_lines end + + //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 == PolyType.ptSubject) + { + e1FillType = m_SubjFillType; + e1FillType2 = m_ClipFillType; + } + else + { + e1FillType = m_ClipFillType; + e1FillType2 = m_SubjFillType; + } + if (e2.PolyTyp == PolyType.ptSubject) + { + e2FillType = m_SubjFillType; + e2FillType2 = m_ClipFillType; + } + else + { + e2FillType = m_ClipFillType; + e2FillType2 = m_SubjFillType; + } + + int e1Wc = Math.Abs(e1.WindCnt); + int e2Wc = Math.Abs(e2.WindCnt); + + if (e1Contributing && e2Contributing) + { + if ((e1Wc != 0 && e1Wc != 1) || (e2Wc != 0 && e2Wc != 1) || + (e1.PolyTyp != e2.PolyTyp && m_ClipType != 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 ... + long e1Wc2 = Math.Abs(e1.WindCnt2); + long e2Wc2 = Math.Abs(e2.WindCnt2); + + if (e1.PolyTyp != e2.PolyTyp) + { + AddLocalMinPoly(e1, e2, pt); + } + else if (e1Wc == 1 && e2Wc == 1) + switch (m_ClipType) + { + case ClipType.ctIntersection: + if (e1Wc2 > 0 && e2Wc2 > 0) + AddLocalMinPoly(e1, e2, pt); + break; + case ClipType.ctUnion: + if (e1Wc2 <= 0 && e2Wc2 <= 0) + AddLocalMinPoly(e1, e2, pt); + break; + case ClipType.ctDifference: + if (((e1.PolyTyp == PolyType.ptClip) && (e1Wc2 > 0) && (e2Wc2 > 0)) || + ((e1.PolyTyp == PolyType.ptSubject) && (e1Wc2 <= 0) && (e2Wc2 <= 0))) + AddLocalMinPoly(e1, e2, pt); + break; + case ClipType.ctXor: + AddLocalMinPoly(e1, e2, pt); + break; + } + else + SwapSides(e1, e2); + } + } + //------------------------------------------------------------------------------ + + private void ProcessHorizontals() + { + //m_SortedEdges; + while (PopEdgeFromSEL(out TEdge horzEdge)) + ProcessHorizontal(horzEdge); + } + //------------------------------------------------------------------------------ + + void GetHorzDirection(TEdge HorzEdge, out Direction Dir, out long Left, out long Right) + { + if (HorzEdge.Bot.X < HorzEdge.Top.X) + { + Left = HorzEdge.Bot.X; + Right = HorzEdge.Top.X; + Dir = Direction.dLeftToRight; + } + else + { + Left = HorzEdge.Top.X; + Right = HorzEdge.Bot.X; + Dir = Direction.dRightToLeft; + } + } + //------------------------------------------------------------------------ + + private void ProcessHorizontal(TEdge horzEdge) + { + bool IsOpen = horzEdge.WindDelta == 0; + + GetHorzDirection(horzEdge, out Direction dir, out long horzLeft, out long horzRight); + + TEdge eLastHorz = horzEdge, eMaxPair = null; + while (eLastHorz.NextInLML != null && IsHorizontal(eLastHorz.NextInLML)) + eLastHorz = eLastHorz.NextInLML; + if (eLastHorz.NextInLML == null) + eMaxPair = GetMaximaPair(eLastHorz); + + Maxima currMax = m_Maxima; + if (currMax != null) + { + //get the first maxima in range (X) ... + if (dir == Direction.dLeftToRight) + { + while (currMax != null && currMax.X <= horzEdge.Bot.X) + currMax = currMax.Next; + if (currMax != null && currMax.X >= eLastHorz.Top.X) + currMax = null; + } + else + { + while (currMax.Next != null && currMax.Next.X < horzEdge.Bot.X) + currMax = currMax.Next; + if (currMax.X <= eLastHorz.Top.X) currMax = null; + } + } + + OutPt op1 = null; + for (; ; ) //loop through consec. horizontal edges + { + bool IsLastHorz = (horzEdge == eLastHorz); + TEdge e = GetNextInAEL(horzEdge, dir); + while (e != null) + { + + //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 (currMax != null) + { + if (dir == Direction.dLeftToRight) + { + while (currMax != null && currMax.X < e.Curr.X) + { + if (horzEdge.OutIdx >= 0 && !IsOpen) + AddOutPt(horzEdge, new IntPoint(currMax.X, horzEdge.Bot.Y)); + currMax = currMax.Next; + } + } + else + { + while (currMax != null && currMax.X > e.Curr.X) + { + if (horzEdge.OutIdx >= 0 && !IsOpen) + AddOutPt(horzEdge, new IntPoint(currMax.X, horzEdge.Bot.Y)); + currMax = currMax.Prev; + } + } + }; + + if ((dir == Direction.dLeftToRight && e.Curr.X > horzRight) || + (dir == Direction.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 != null && + e.Dx < horzEdge.NextInLML.Dx) break; + + if (horzEdge.OutIdx >= 0 && !IsOpen) //note: may be done multiple times + { + op1 = AddOutPt(horzEdge, e.Curr); + TEdge eNextHorz = m_SortedEdges; + while (eNextHorz != null) + { + 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 == Direction.dLeftToRight) + { + IntPoint Pt = new IntPoint(e.Curr.X, horzEdge.Curr.Y); + IntersectEdges(horzEdge, e, Pt); + } + else + { + IntPoint Pt = new IntPoint(e.Curr.X, horzEdge.Curr.Y); + IntersectEdges(e, horzEdge, Pt); + } + TEdge eNext = GetNextInAEL(e, dir); + SwapPositionsInAEL(horzEdge, e); + e = eNext; + } //end while(e != null) + + //Break out of loop if HorzEdge.NextInLML is not also horizontal ... + if (horzEdge.NextInLML == null || !IsHorizontal(horzEdge.NextInLML)) break; + + UpdateEdgeIntoAEL(ref horzEdge); + if (horzEdge.OutIdx >= 0) AddOutPt(horzEdge, horzEdge.Bot); + GetHorzDirection(horzEdge, out dir, out horzLeft, out horzRight); + + } //end for (;;) + + if (horzEdge.OutIdx >= 0 && op1 == null) + { + op1 = GetLastOutPt(horzEdge); + TEdge eNextHorz = m_SortedEdges; + while (eNextHorz != null) + { + 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 != null) + { + if (horzEdge.OutIdx >= 0) + { + op1 = AddOutPt(horzEdge, horzEdge.Top); + + UpdateEdgeIntoAEL(ref horzEdge); + if (horzEdge.WindDelta == 0) return; + //nb: HorzEdge is no longer horizontal here + TEdge ePrev = horzEdge.PrevInAEL; + TEdge eNext = horzEdge.NextInAEL; + if (ePrev != null && 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 != null && 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(ref horzEdge); + } + else + { + if (horzEdge.OutIdx >= 0) AddOutPt(horzEdge, horzEdge.Top); + DeleteFromAEL(horzEdge); + } + } + //------------------------------------------------------------------------------ + + private TEdge GetNextInAEL(TEdge e, Direction Direction) + { + return Direction == Direction.dLeftToRight ? e.NextInAEL : e.PrevInAEL; + } + //------------------------------------------------------------------------------ + + private bool IsMaxima(TEdge e, double Y) + { + return (e != null && e.Top.Y == Y && e.NextInLML == null); + } + //------------------------------------------------------------------------------ + + private bool IsIntermediate(TEdge e, double Y) + { + return (e.Top.Y == Y && e.NextInLML != null); + } + //------------------------------------------------------------------------------ + + internal TEdge GetMaximaPair(TEdge e) + { + if ((e.Next.Top == e.Top) && e.Next.NextInLML == null) + return e.Next; + else if ((e.Prev.Top == e.Top) && e.Prev.NextInLML == null) + return e.Prev; + else + return null; + } + //------------------------------------------------------------------------------ + + internal TEdge GetMaximaPairEx(TEdge e) + { + //as above but returns null if MaxPair isn't in AEL (unless it's horizontal) + TEdge result = GetMaximaPair(e); + if (result == null || result.OutIdx == Skip || + ((result.NextInAEL == result.PrevInAEL) && !IsHorizontal(result))) return null; + return result; + } + //------------------------------------------------------------------------------ + + private bool ProcessIntersections(long topY) + { + if (m_ActiveEdges == null) return true; + try + { + BuildIntersectList(topY); + if (m_IntersectList.Count == 0) return true; + if (m_IntersectList.Count == 1 || FixupIntersectionOrder()) + ProcessIntersectList(); + else + return false; + } + catch + { + m_SortedEdges = null; + m_IntersectList.Clear(); + throw new ClipperException("ProcessIntersections error"); + } + m_SortedEdges = null; + return true; + } + //------------------------------------------------------------------------------ + + private void BuildIntersectList(long topY) + { + if (m_ActiveEdges == null) return; + + //prepare for sorting ... + TEdge e = m_ActiveEdges; + m_SortedEdges = e; + while (e != null) + { + e.PrevInSEL = e.PrevInAEL; + e.NextInSEL = e.NextInAEL; + e.Curr.X = TopX(e, topY); + e = e.NextInAEL; + } + + //bubblesort ... + bool isModified = true; + while (isModified && m_SortedEdges != null) + { + isModified = false; + e = m_SortedEdges; + while (e.NextInSEL != null) + { + TEdge eNext = e.NextInSEL; + if (e.Curr.X > eNext.Curr.X) + { + IntersectPoint(e, eNext, out IntPoint pt); + if (pt.Y < topY) + pt = new IntPoint(TopX(e, topY), topY); + IntersectNode newNode = new IntersectNode + { + Edge1 = e, + Edge2 = eNext, + Pt = pt + }; + m_IntersectList.Add(newNode); + + SwapPositionsInSEL(e, eNext); + isModified = true; + } + else + e = eNext; + } + if (e.PrevInSEL != null) e.PrevInSEL.NextInSEL = null; + else break; + } + m_SortedEdges = null; + } + //------------------------------------------------------------------------------ + + private bool EdgesAdjacent(IntersectNode inode) + { + return (inode.Edge1.NextInSEL == inode.Edge2) || + (inode.Edge1.PrevInSEL == inode.Edge2); + } + //------------------------------------------------------------------------------ + + private bool 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 ... + m_IntersectList.Sort(m_IntersectNodeComparer); + + CopyAELToSEL(); + int cnt = m_IntersectList.Count; + for (int i = 0; i < cnt; i++) + { + if (!EdgesAdjacent(m_IntersectList[i])) + { + int j = i + 1; + while (j < cnt && !EdgesAdjacent(m_IntersectList[j])) j++; + if (j == cnt) return false; + + IntersectNode tmp = m_IntersectList[i]; + m_IntersectList[i] = m_IntersectList[j]; + m_IntersectList[j] = tmp; + + } + SwapPositionsInSEL(m_IntersectList[i].Edge1, m_IntersectList[i].Edge2); + } + return true; + } + //------------------------------------------------------------------------------ + + private void ProcessIntersectList() + { + for (int i = 0; i < m_IntersectList.Count; i++) + { + IntersectNode iNode = m_IntersectList[i]; + { + IntersectEdges(iNode.Edge1, iNode.Edge2, iNode.Pt); + SwapPositionsInAEL(iNode.Edge1, iNode.Edge2); + } + } + m_IntersectList.Clear(); + } + //------------------------------------------------------------------------------ + + internal static long Round(double value) + { + return value < 0 ? (long)(value - 0.5) : (long)(value + 0.5); + } + //------------------------------------------------------------------------------ + + private static long TopX(TEdge edge, long currentY) + { + if (currentY == edge.Top.Y) + return edge.Top.X; + return edge.Bot.X + Round(edge.Dx * (currentY - edge.Bot.Y)); + } + //------------------------------------------------------------------------------ + + private void IntersectPoint(TEdge edge1, TEdge edge2, out IntPoint ip) + { + ip = new IntPoint(); + double b1, b2; + //nb: with very large coordinate values, it's possible for SlopesEqual() to + //return false but for the edge.Dx value be equal due to double precision rounding. + if (edge1.Dx == edge2.Dx) + { + ip.Y = edge1.Curr.Y; + ip.X = TopX(edge1, ip.Y); + return; + } + + if (edge1.Delta.X == 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.Delta.X == 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 (Math.Abs(edge1.Dx) < Math.Abs(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 (Math.Abs(edge1.Dx) < Math.Abs(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; + //better to use the more vertical edge to derive X ... + if (Math.Abs(edge1.Dx) > Math.Abs(edge2.Dx)) + ip.X = TopX(edge2, ip.Y); + else + ip.X = TopX(edge1, ip.Y); + } + } + //------------------------------------------------------------------------------ + + private void ProcessEdgesAtTopOfScanbeam(long topY) + { + TEdge e = m_ActiveEdges; + while (e != null) + { + //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 == null || !IsHorizontal(eMaxPair)); + } + + if (IsMaximaEdge) + { + if (StrictlySimple) InsertMaxima(e.Top.X); + TEdge ePrev = e.PrevInAEL; + DoMaxima(e); + if (ePrev == null) 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(ref e); + if (e.OutIdx >= 0) + AddOutPt(e, e.Bot); + AddEdgeToSEL(e); + } + else + { + e.Curr.X = TopX(e, topY); + e.Curr.Y = topY; + } + //When StrictlySimple and 'e' is being touched by another edge, then + //make sure both edges have a vertex here ... + if (StrictlySimple) + { + TEdge ePrev = e.PrevInAEL; + if ((e.OutIdx >= 0) && (e.WindDelta != 0) && ePrev != null && + (ePrev.OutIdx >= 0) && (ePrev.Curr.X == e.Curr.X) && + (ePrev.WindDelta != 0)) + { + IntPoint ip = new IntPoint(e.Curr); + OutPt op = AddOutPt(ePrev, ip); + OutPt op2 = AddOutPt(e, ip); + AddJoin(op, op2, ip); //StrictlySimple (type-3) join + } + } + + e = e.NextInAEL; + } + } + + //3. Process horizontals at the Top of the scanbeam ... + ProcessHorizontals(); + m_Maxima = null; + + //4. Promote intermediate vertices ... + e = m_ActiveEdges; + while (e != null) + { + if (IsIntermediate(e, topY)) + { + OutPt op = null; + if (e.OutIdx >= 0) + op = AddOutPt(e, e.Top); + UpdateEdgeIntoAEL(ref e); + + //if output polygons share an edge, they'll need joining later ... + TEdge ePrev = e.PrevInAEL; + TEdge eNext = e.NextInAEL; + if (ePrev != null && ePrev.Curr.X == e.Bot.X && + ePrev.Curr.Y == e.Bot.Y && op != null && + 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 != null && eNext.Curr.X == e.Bot.X && + eNext.Curr.Y == e.Bot.Y && op != null && + 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; + } + } + //------------------------------------------------------------------------------ + + private void DoMaxima(TEdge e) + { + TEdge eMaxPair = GetMaximaPairEx(e); + if (eMaxPair == null) + { + if (e.OutIdx >= 0) + AddOutPt(e, e.Top); + DeleteFromAEL(e); + return; + } + + TEdge eNext = e.NextInAEL; + while (eNext != null && 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); + } + + // use_lines start + 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); + } + // use_lines end + + else throw new ClipperException("DoMaxima error"); + } + //------------------------------------------------------------------------------ + + public static void ReversePaths(List> polys) + { + foreach (var poly in polys) { poly.Reverse(); } + } + //------------------------------------------------------------------------------ + + public static bool Orientation(List poly) + { + return Area(poly) >= 0; + } + //------------------------------------------------------------------------------ + + private int PointCount(OutPt pts) + { + if (pts == null) return 0; + int result = 0; + OutPt p = pts; + do + { + result++; + p = p.Next; + } + while (p != pts); + return result; + } + //------------------------------------------------------------------------------ + + private void BuildResult(List> polyg) + { + polyg.Clear(); + polyg.Capacity = m_PolyOuts.Count; + for (int i = 0; i < m_PolyOuts.Count; i++) + { + OutRec outRec = m_PolyOuts[i]; + if (outRec.Pts == null) continue; + OutPt p = outRec.Pts.Prev; + int cnt = PointCount(p); + if (cnt < 2) continue; + List pg = new List(cnt); + for (int j = 0; j < cnt; j++) + { + pg.Add(p.Pt); + p = p.Prev; + } + polyg.Add(pg); + } + } + //------------------------------------------------------------------------------ + + private void BuildResult2(PolyTree polytree) + { + polytree.Clear(); + + //add each output polygon/contour to polytree ... + polytree.m_AllPolys.Capacity = m_PolyOuts.Count; + for (int i = 0; i < m_PolyOuts.Count; 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(); + polytree.m_AllPolys.Add(pn); + outRec.PolyNode = pn; + pn.m_polygon.Capacity = cnt; + OutPt op = outRec.Pts.Prev; + for (int j = 0; j < cnt; j++) + { + pn.m_polygon.Add(op.Pt); + op = op.Prev; + } + } + + //fixup PolyNode links etc ... + polytree.m_Childs.Capacity = m_PolyOuts.Count; + for (int i = 0; i < m_PolyOuts.Count; i++) + { + OutRec outRec = m_PolyOuts[i]; + if (outRec.PolyNode == null) continue; + else if (outRec.IsOpen) + { + outRec.PolyNode.IsOpen = true; + polytree.AddChild(outRec.PolyNode); + } + else if (outRec.FirstLeft != null && + outRec.FirstLeft.PolyNode != null) + outRec.FirstLeft.PolyNode.AddChild(outRec.PolyNode); + else + polytree.AddChild(outRec.PolyNode); + } + } + //------------------------------------------------------------------------------ + + private void 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; + pp = tmpPP; + } + } + if (pp == pp.Prev) outrec.Pts = null; + } + //------------------------------------------------------------------------------ + + private void FixupOutPolygon(OutRec outRec) + { + //FixupOutPolygon() - removes duplicate points and simplifies consecutive + //parallel edges by removing the middle vertex. + OutPt lastOK = null; + outRec.BottomPt = null; + OutPt pp = outRec.Pts; + bool preserveCol = PreserveCollinear || StrictlySimple; + for (; ; ) + { + if (pp.Prev == pp || pp.Prev == pp.Next) + { + outRec.Pts = null; + 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 = null; + pp.Prev.Next = pp.Next; + pp.Next.Prev = pp.Prev; + pp = pp.Prev; + } + else if (pp == lastOK) break; + else + { + if (lastOK == null) lastOK = pp; + pp = pp.Next; + } + } + outRec.Pts = pp; + } + //------------------------------------------------------------------------------ + + OutPt DupOutPt(OutPt outPt, bool InsertAfter) + { + OutPt result = new OutPt + { + Pt = outPt.Pt, + 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 GetOverlap(long a1, long a2, long b1, long b2, out long Left, out long Right) + { + if (a1 < a2) + { + if (b1 < b2) { Left = Math.Max(a1, b1); Right = Math.Min(a2, b2); } + else { Left = Math.Max(a1, b2); Right = Math.Min(a2, b1); } + } + else + { + if (b1 < b2) { Left = Math.Max(a2, b1); Right = Math.Min(a1, b2); } + else { Left = Math.Max(a2, b2); Right = Math.Min(a1, b1); } + } + return Left < Right; + } + //------------------------------------------------------------------------------ + + bool JoinHorz(OutPt op1, OutPt op1b, OutPt op2, OutPt op2b, + IntPoint Pt, bool DiscardLeft) + { + Direction Dir1 = (op1.Pt.X > op1b.Pt.X ? + Direction.dRightToLeft : Direction.dLeftToRight); + Direction Dir2 = (op2.Pt.X > op2b.Pt.X ? + Direction.dRightToLeft : Direction.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 == Direction.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 == Direction.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 == Direction.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; + } + //------------------------------------------------------------------------------ + + private bool 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. StrictlySimple 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' + + //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, out long Left, out long 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; + } + } + } + //---------------------------------------------------------------------- + + /// + /// returns 0 if false, +1 if true, -1 if pt ON polygon boundary. + /// See "The Point in Polygon Problem for Arbitrary Polygons" by Hormann and Agathos + /// + /// + /// + /// + public static int PointInPolygon(IntPoint pt, List path) + { + // http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.88.5498&rep=rep1&type=pdf + int result = 0, cnt = path.Count; + if (cnt < 3) return 0; + IntPoint ip = path[0]; + for (int 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 == 0) return -1; + else 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 == 0) return -1; + else if ((d > 0) == (ipNext.Y > ip.Y)) result = 1 - result; + } + } + } + ip = ipNext; + } + return result; + } + //------------------------------------------------------------------------------ + + //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 + private static int PointInPolygon(IntPoint pt, OutPt op) + { + //returns 0 if false, +1 if true, -1 if pt ON polygon boundary + int result = 0; + OutPt startOp = op; + long ptx = pt.X, pty = pt.Y; + long poly0x = op.Pt.X, poly0y = op.Pt.Y; + do + { + op = op.Next; + long poly1x = op.Pt.X, poly1y = op.Pt.Y; + + if (poly1y == pty) + { + if ((poly1x == ptx) || (poly0y == pty && + ((poly1x > ptx) == (poly0x < ptx)))) return -1; + } + if ((poly0y < pty) != (poly1y < pty)) + { + if (poly0x >= ptx) + { + if (poly1x > ptx) result = 1 - result; + else + { + double d = (double)(poly0x - ptx) * (poly1y - pty) - + (double)(poly1x - ptx) * (poly0y - pty); + if (d == 0) return -1; + if ((d > 0) == (poly1y > poly0y)) result = 1 - result; + } + } + else + { + if (poly1x > ptx) + { + double d = (double)(poly0x - ptx) * (poly1y - pty) - + (double)(poly1x - ptx) * (poly0y - pty); + if (d == 0) return -1; + if ((d > 0) == (poly1y > poly0y)) result = 1 - result; + } + } + } + poly0x = poly1x; poly0y = poly1y; + } while (startOp != op); + return result; + } + //------------------------------------------------------------------------------ + + private static 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; + } + //---------------------------------------------------------------------- + + private void FixupFirstLefts1(OutRec OldOutRec, OutRec NewOutRec) + { + foreach (OutRec outRec in m_PolyOuts) + { + OutRec firstLeft = ParseFirstLeft(outRec.FirstLeft); + if (outRec.Pts != null && firstLeft == OldOutRec) + { + if (Poly2ContainsPoly1(outRec.Pts, NewOutRec.Pts)) + outRec.FirstLeft = NewOutRec; + } + } + } + //---------------------------------------------------------------------- + + private void 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 nil) to see if they've become inner to the new inner polygon ... + OutRec orfl = outerOutRec.FirstLeft; + foreach (OutRec outRec in m_PolyOuts) + { + if (outRec.Pts == null || 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; + } + } + //---------------------------------------------------------------------- + + private void FixupFirstLefts3(OutRec OldOutRec, OutRec NewOutRec) + { + //same as FixupFirstLefts1 but doesn't call Poly2ContainsPoly1() + foreach (OutRec outRec in m_PolyOuts) + { + OutRec firstLeft = ParseFirstLeft(outRec.FirstLeft); + if (outRec.Pts != null && firstLeft == OldOutRec) + outRec.FirstLeft = NewOutRec; + } + } + //---------------------------------------------------------------------- + + private static OutRec ParseFirstLeft(OutRec FirstLeft) + { + while (FirstLeft != null && FirstLeft.Pts == null) + FirstLeft = FirstLeft.FirstLeft; + return FirstLeft; + } + //------------------------------------------------------------------------------ + + private void JoinCommonEdges() + { + for (int i = 0; i < m_Joins.Count; i++) + { + Join join = m_Joins[i]; + + OutRec outRec1 = GetOutRec(join.OutPt1.Idx); + OutRec outRec2 = GetOutRec(join.OutPt2.Idx); + + if (outRec1.Pts == null || outRec2.Pts == null) 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 = null; + 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 ^ ReverseSolution) == (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 ^ ReverseSolution) == (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 = null; + outRec2.BottomPt = null; + outRec2.Idx = outRec1.Idx; + + outRec1.IsHole = holeStateRec.IsHole; + if (holeStateRec == outRec2) + outRec1.FirstLeft = outRec2.FirstLeft; + outRec2.FirstLeft = outRec1; + + //fixup FirstLeft pointers that may need reassigning to OutRec1 + if (m_UsingPolyTree) FixupFirstLefts3(outRec2, outRec1); + } + } + } + //------------------------------------------------------------------------------ + + private void UpdateOutPtIdxs(OutRec outrec) + { + OutPt op = outrec.Pts; + do + { + op.Idx = outrec.Idx; + op = op.Prev; + } + while (op != outrec.Pts); + } + //------------------------------------------------------------------------------ + + private void DoSimplePolygons() + { + int i = 0; + while (i < m_PolyOuts.Count) + { + OutRec outrec = m_PolyOuts[i++]; + OutPt op = outrec.Pts; + if (op == null || 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); + } + } + //------------------------------------------------------------------------------ + + public static double Area(List poly) + { + int cnt = poly.Count; + if (cnt < 3) return 0; + double a = 0; + for (int i = 0, j = cnt - 1; i < cnt; ++i) + { + a += ((double)poly[j].X + poly[i].X) * ((double)poly[j].Y - poly[i].Y); + j = i; + } + return -a * 0.5; + } + //------------------------------------------------------------------------------ + + internal double Area(OutRec outRec) + { + return Area(outRec.Pts); + } + //------------------------------------------------------------------------------ + + internal double Area(OutPt op) + { + OutPt opFirst = op; + if (op == null) 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 != opFirst); + return a * 0.5; + } + + //------------------------------------------------------------------------------ + // SimplifyPolygon functions ... + // Convert self-intersecting polygons into simple polygons + //------------------------------------------------------------------------------ + /// + /// Convert self-intersecting polygons into simple polygons. + /// + /// + /// + /// + public static List> SimplifyPolygon(List poly, + PolyFillType fillType = PolyFillType.pftEvenOdd) + { + List> result = new List>(); + Clipper c = new Clipper + { + StrictlySimple = true + }; + c.AddPath(poly, PolyType.ptSubject, true); + c.Execute(ClipType.ctUnion, result, fillType, fillType); + return result; + } + //------------------------------------------------------------------------------ + /// + /// Convert self-intersecting polygons into simple polygons. + /// + /// + /// + /// + public static List> SimplifyPolygons(List> polys, + PolyFillType fillType = PolyFillType.pftEvenOdd) + { + List> result = new List>(); + Clipper c = new Clipper + { + StrictlySimple = true + }; + c.AddPaths(polys, PolyType.ptSubject, true); + c.Execute(ClipType.ctUnion, result, fillType, fillType); + return result; + } + //------------------------------------------------------------------------------ + + private static double DistanceFromLineSqrd(IntPoint pt, IntPoint ln1, IntPoint ln2) + { + //The equation of a line in general form (Ax + By + C = 0) + //given 2 points (x¹,y¹) & (x²,y²) is ... + //(y¹ - y²)x + (x² - x¹)y + (y² - y¹)x¹ - (x² - x¹)y¹ = 0 + //A = (y¹ - y²); B = (x² - x¹); C = (y² - y¹)x¹ - (x² - x¹)y¹ + //perpendicular distance of point (x³,y³) = (Ax³ + By³ + C)/Sqrt(A² + B²) + //see http://en.wikipedia.org/wiki/Perpendicular_distance + double A = ln1.Y - ln2.Y; + double B = 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); + } + //--------------------------------------------------------------------------- + + /// + /// This function is more accurate when the point that's GEOMETRICALLY between the other + /// 2 points is the one that's tested for distance. + /// nb: with 'spikes', either pt1 or pt3 is geometrically between the other pts"> + /// + /// + /// + /// + /// + /// + private static bool SlopesNearCollinear(IntPoint pt1, + IntPoint pt2, IntPoint pt3, double distSqrd) + { + if (Math.Abs(pt1.X - pt2.X) > Math.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; + } + } + //------------------------------------------------------------------------------ + + private static 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); + } + //------------------------------------------------------------------------------ + + private static OutPt ExcludeOp(OutPt op) + { + OutPt result = op.Prev; + result.Next = op.Next; + op.Next.Prev = result; + result.Idx = 0; + return result; + } + //------------------------------------------------------------------------------ + /// + /// + /// + /// + /// proximity in units/pixels below which vertices will be stripped. + /// Default ~= sqrt(2) so when adjacent vertices or semi-adjacent vertices have both x and y coords within 1 unit, then the second vertex will be stripped. + public static List CleanPolygon(List path, double distance = 1.415) + { + //distance = proximity in units/pixels below which vertices will be stripped. + //Default ~= sqrt(2) so when adjacent vertices or semi-adjacent vertices have + //both x & y coords within 1 unit, then the second vertex will be stripped. + + int cnt = path.Count; + + if (cnt == 0) return new List(); + + OutPt[] outPts = new OutPt[cnt]; + for (int i = 0; i < cnt; ++i) outPts[i] = new OutPt(); + + for (int i = 0; i < cnt; ++i) + { + outPts[i].Pt = path[i]; + outPts[i].Next = outPts[(i + 1) % cnt]; + 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); + cnt--; + } + else if (PointsAreClose(op.Prev.Pt, op.Next.Pt, distSqrd)) + { + ExcludeOp(op.Next); + op = ExcludeOp(op); + cnt -= 2; + } + else if (SlopesNearCollinear(op.Prev.Pt, op.Pt, op.Next.Pt, distSqrd)) + { + op = ExcludeOp(op); + cnt--; + } + else + { + op.Idx = 1; + op = op.Next; + } + } + + if (cnt < 3) cnt = 0; + List result = new List(cnt); + for (int i = 0; i < cnt; ++i) + { + result.Add(op.Pt); + op = op.Next; + } + outPts = null; + return result; + } + //------------------------------------------------------------------------------ + + /// + /// + /// + /// + /// proximity in units/pixels below which vertices will be stripped. + /// Default ~= sqrt(2) so when adjacent vertices or semi-adjacent vertices have both x and y coords within 1 unit, then the second vertex will be stripped. + public static List> CleanPolygons(List> polys, + double distance = 1.415) + { + List> result = new List>(polys.Count); + for (int i = 0; i < polys.Count; i++) + result.Add(CleanPolygon(polys[i], distance)); + return result; + } + //------------------------------------------------------------------------------ + + internal static List> Minkowski(List pattern, List path, bool IsSum, bool IsClosed) + { + int delta = (IsClosed ? 1 : 0); + int polyCnt = pattern.Count; + int pathCnt = path.Count; + List> result = new List>(pathCnt); + if (IsSum) + for (int i = 0; i < pathCnt; i++) + { + List p = new List(polyCnt); + foreach (IntPoint ip in pattern) + p.Add(new IntPoint(path[i].X + ip.X, path[i].Y + ip.Y)); + result.Add(p); + } + else + for (int i = 0; i < pathCnt; i++) + { + List p = new List(polyCnt); + foreach (IntPoint ip in pattern) + p.Add(new IntPoint(path[i].X - ip.X, path[i].Y - ip.Y)); + result.Add(p); + } + + List> quads = new List>((pathCnt + delta) * (polyCnt + 1)); + for (int i = 0; i < pathCnt - 1 + delta; i++) + for (int j = 0; j < polyCnt; j++) + { + List quad = new List(4) + { + result[i % pathCnt][j % polyCnt], + result[(i + 1) % pathCnt][j % polyCnt], + result[(i + 1) % pathCnt][(j + 1) % polyCnt], + result[i % pathCnt][(j + 1) % polyCnt] + }; + if (!Orientation(quad)) quad.Reverse(); + quads.Add(quad); + } + return quads; + } + //------------------------------------------------------------------------------ + + public static List> MinkowskiSum(List pattern, List path, bool pathIsClosed) + { + List> paths = Minkowski(pattern, path, true, pathIsClosed); + Clipper c = new Clipper(); + c.AddPaths(paths, PolyType.ptSubject, true); + c.Execute(ClipType.ctUnion, paths, PolyFillType.pftNonZero, PolyFillType.pftNonZero); + return paths; + } + //------------------------------------------------------------------------------ + + private static List TranslatePath(List path, IntPoint delta) + { + List outPath = new List(path.Count); + for (int i = 0; i < path.Count; i++) + outPath.Add(new IntPoint(path[i].X + delta.X, path[i].Y + delta.Y)); + return outPath; + } + //------------------------------------------------------------------------------ + + public static List> MinkowskiSum(List pattern, List> paths, bool pathIsClosed) + { + List> solution = new List>(); + Clipper c = new Clipper(); + for (int i = 0; i < paths.Count; ++i) + { + List> tmp = Minkowski(pattern, paths[i], true, pathIsClosed); + c.AddPaths(tmp, PolyType.ptSubject, true); + if (pathIsClosed) + { + List path = TranslatePath(paths[i], pattern[0]); + c.AddPath(path, PolyType.ptClip, true); + } + } + c.Execute(ClipType.ctUnion, solution, + PolyFillType.pftNonZero, PolyFillType.pftNonZero); + return solution; + } + //------------------------------------------------------------------------------ + + public static List> MinkowskiDiff(List poly1, List poly2) + { + List> paths = Minkowski(poly1, poly2, false, true); + Clipper c = new Clipper(); + c.AddPaths(paths, PolyType.ptSubject, true); + c.Execute(ClipType.ctUnion, paths, PolyFillType.pftNonZero, PolyFillType.pftNonZero); + return paths; + } + //------------------------------------------------------------------------------ + + internal enum NodeType { ntAny, ntOpen, ntClosed }; + + public static List> PolyTreeToPaths(PolyTree polytree) + { + + List> result = new List> + { + Capacity = polytree.Total + }; + AddPolyNodeToPaths(polytree, NodeType.ntAny, result); + return result; + } + //------------------------------------------------------------------------------ + + internal static void AddPolyNodeToPaths(PolyNode polynode, NodeType nt, List> paths) + { + bool match = true; + switch (nt) + { + case NodeType.ntOpen: return; + case NodeType.ntClosed: match = !polynode.IsOpen; break; + default: break; + } + + if (polynode.m_polygon.Count > 0 && match) + paths.Add(polynode.m_polygon); + foreach (PolyNode pn in polynode.Childs) + AddPolyNodeToPaths(pn, nt, paths); + } + //------------------------------------------------------------------------------ + + public static List> OpenPathsFromPolyTree(PolyTree polytree) + { + List> result = new List> + { + Capacity = polytree.ChildCount + }; + for (int i = 0; i < polytree.ChildCount; i++) + if (polytree.Childs[i].IsOpen) + result.Add(polytree.Childs[i].m_polygon); + return result; + } + //------------------------------------------------------------------------------ + + public static List> ClosedPathsFromPolyTree(PolyTree polytree) + { + List> result = new List> + { + Capacity = polytree.Total + }; + AddPolyNodeToPaths(polytree, NodeType.ntClosed, result); + return result; + } + //------------------------------------------------------------------------------ + + } //end Clipper + + internal class ClipperOffset + { + private List> m_destPolys; + private List m_srcPoly; + private List m_destPoly; + private readonly List m_normals = new List(); + private double m_delta, m_sinA, m_sin, m_cos; + private double m_miterLim, m_StepsPerRad; + + private IntPoint m_lowest; + private readonly PolyNode m_polyNodes = new PolyNode(); + + public double ArcTolerance { get; set; } + + public double MiterLimit { get; set; } + + private const double two_pi = Math.PI * 2; + private const double def_arc_tolerance = 0.25; + + public ClipperOffset( + double miterLimit = 2.0, double arcTolerance = def_arc_tolerance) + { + MiterLimit = miterLimit; + ArcTolerance = arcTolerance; + m_lowest.X = -1; + } + //------------------------------------------------------------------------------ + + public void Clear() + { + m_polyNodes.Childs.Clear(); + m_lowest.X = -1; + } + //------------------------------------------------------------------------------ + + internal static long Round(double value) + { + return value < 0 ? (long)(value - 0.5) : (long)(value + 0.5); + } + //------------------------------------------------------------------------------ + + public void AddPath(List path, JoinType joinType, EndType endType) + { + int highI = path.Count - 1; + if (highI < 0) return; + PolyNode newNode = new PolyNode + { + m_jointype = joinType, + m_endtype = endType + }; + + //strip duplicate points from path and also get index to the lowest point ... + if (endType == EndType.etClosedLine || endType == EndType.etClosedPolygon) + while (highI > 0 && path[0] == path[highI]) highI--; + newNode.m_polygon.Capacity = highI + 1; + newNode.m_polygon.Add(path[0]); + int j = 0, k = 0; + for (int i = 1; i <= highI; i++) + if (newNode.m_polygon[j] != path[i]) + { + j++; + newNode.m_polygon.Add(path[i]); + if (path[i].Y > newNode.m_polygon[k].Y || + (path[i].Y == newNode.m_polygon[k].Y && + path[i].X < newNode.m_polygon[k].X)) k = j; + } + if (endType == EndType.etClosedPolygon && j < 2) return; + + m_polyNodes.AddChild(newNode); + + //if this path's lowest pt is lower than all the others then update m_lowest + if (endType != EndType.etClosedPolygon) return; + if (m_lowest.X < 0) + m_lowest = new IntPoint(m_polyNodes.ChildCount - 1, k); + else + { + IntPoint ip = m_polyNodes.Childs[(int)m_lowest.X].m_polygon[(int)m_lowest.Y]; + if (newNode.m_polygon[k].Y > ip.Y || + (newNode.m_polygon[k].Y == ip.Y && + newNode.m_polygon[k].X < ip.X)) + m_lowest = new IntPoint(m_polyNodes.ChildCount - 1, k); + } + } + //------------------------------------------------------------------------------ + + public void AddPaths(List> paths, JoinType joinType, EndType endType) + { + foreach (List p in paths) + AddPath(p, joinType, endType); + } + //------------------------------------------------------------------------------ + + private void 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 && + !Clipper.Orientation(m_polyNodes.Childs[(int)m_lowest.X].m_polygon)) + { + for (int i = 0; i < m_polyNodes.ChildCount; i++) + { + PolyNode node = m_polyNodes.Childs[i]; + if (node.m_endtype == EndType.etClosedPolygon || + (node.m_endtype == EndType.etClosedLine && + Clipper.Orientation(node.m_polygon))) + node.m_polygon.Reverse(); + } + } + else + { + for (int i = 0; i < m_polyNodes.ChildCount; i++) + { + PolyNode node = m_polyNodes.Childs[i]; + if (node.m_endtype == EndType.etClosedLine && + !Clipper.Orientation(node.m_polygon)) + node.m_polygon.Reverse(); + } + } + } + //------------------------------------------------------------------------------ + + internal static DoublePoint GetUnitNormal(IntPoint pt1, IntPoint pt2) + { + double dx = (pt2.X - pt1.X); + double dy = (pt2.Y - pt1.Y); + if ((dx == 0) && (dy == 0)) return new DoublePoint(); + + double f = 1 * 1.0 / Math.Sqrt(dx * dx + dy * dy); + dx *= f; + dy *= f; + + return new DoublePoint(dy, -dx); + } + //------------------------------------------------------------------------------ + + private void DoOffset(double delta) + { + m_destPolys = new List>(); + m_delta = delta; + + //if Zero offset, just copy any CLOSED polygons to m_p and return ... + if (ClipperBase.NearZero(delta)) + { + m_destPolys.Capacity = m_polyNodes.ChildCount; + for (int i = 0; i < m_polyNodes.ChildCount; i++) + { + PolyNode node = m_polyNodes.Childs[i]; + if (node.m_endtype == EndType.etClosedPolygon) + m_destPolys.Add(node.m_polygon); + } + 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 > Math.Abs(delta) * def_arc_tolerance) + y = Math.Abs(delta) * def_arc_tolerance; + else + y = ArcTolerance; + //see offset_triginometry2.svg in the documentation folder ... + double steps = Math.PI / Math.Acos(1 - y / Math.Abs(delta)); + m_sin = Math.Sin(two_pi / steps); + m_cos = Math.Cos(two_pi / steps); + m_StepsPerRad = steps / two_pi; + if (delta < 0.0) m_sin = -m_sin; + + m_destPolys.Capacity = m_polyNodes.ChildCount * 2; + for (int i = 0; i < m_polyNodes.ChildCount; i++) + { + PolyNode node = m_polyNodes.Childs[i]; + m_srcPoly = node.m_polygon; + + int len = m_srcPoly.Count; + + if (len == 0 || (delta <= 0 && (len < 3 || + node.m_endtype != EndType.etClosedPolygon))) + continue; + + m_destPoly = new List(); + + if (len == 1) + { + if (node.m_jointype == JoinType.jtRound) + { + double X = 1.0, Y = 0.0; + for (int j = 1; j <= steps; j++) + { + m_destPoly.Add(new 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.Add(new 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.Add(m_destPoly); + continue; + } + + //build m_normals ... + m_normals.Clear(); + m_normals.Capacity = len; + for (int j = 0; j < len - 1; j++) + m_normals.Add(GetUnitNormal(m_srcPoly[j], m_srcPoly[j + 1])); + if (node.m_endtype == EndType.etClosedLine || + node.m_endtype == EndType.etClosedPolygon) + m_normals.Add(GetUnitNormal(m_srcPoly[len - 1], m_srcPoly[0])); + else + m_normals.Add(new DoublePoint(m_normals[len - 2])); + + if (node.m_endtype == EndType.etClosedPolygon) + { + int k = len - 1; + for (int j = 0; j < len; j++) + OffsetPoint(j, ref k, node.m_jointype); + m_destPolys.Add(m_destPoly); + } + else if (node.m_endtype == EndType.etClosedLine) + { + int k = len - 1; + for (int j = 0; j < len; j++) + OffsetPoint(j, ref k, node.m_jointype); + m_destPolys.Add(m_destPoly); + m_destPoly = new List(); + //re-build m_normals ... + DoublePoint n = m_normals[len - 1]; + for (int j = len - 1; j > 0; j--) + m_normals[j] = new DoublePoint(-m_normals[j - 1].X, -m_normals[j - 1].Y); + m_normals[0] = new DoublePoint(-n.X, -n.Y); + k = 0; + for (int j = len - 1; j >= 0; j--) + OffsetPoint(j, ref k, node.m_jointype); + m_destPolys.Add(m_destPoly); + } + else + { + int k = 0; + for (int j = 1; j < len - 1; ++j) + OffsetPoint(j, ref k, node.m_jointype); + + IntPoint pt1; + if (node.m_endtype == EndType.etOpenButt) + { + int j = len - 1; + pt1 = new IntPoint((long)Round(m_srcPoly[j].X + m_normals[j].X * + delta), (long)Round(m_srcPoly[j].Y + m_normals[j].Y * delta)); + m_destPoly.Add(pt1); + pt1 = new IntPoint((long)Round(m_srcPoly[j].X - m_normals[j].X * + delta), (long)Round(m_srcPoly[j].Y - m_normals[j].Y * delta)); + m_destPoly.Add(pt1); + } + else + { + int j = len - 1; + k = len - 2; + m_sinA = 0; + m_normals[j] = new DoublePoint(-m_normals[j].X, -m_normals[j].Y); + if (node.m_endtype == EndType.etOpenSquare) + DoSquare(j, k); + else + DoRound(j, k); + } + + //re-build m_normals ... + for (int j = len - 1; j > 0; j--) + m_normals[j] = new DoublePoint(-m_normals[j - 1].X, -m_normals[j - 1].Y); + + m_normals[0] = new DoublePoint(-m_normals[1].X, -m_normals[1].Y); + + k = len - 1; + for (int j = k - 1; j > 0; --j) + OffsetPoint(j, ref k, node.m_jointype); + + if (node.m_endtype == EndType.etOpenButt) + { + pt1 = new IntPoint(Round(m_srcPoly[0].X - m_normals[0].X * delta), + Round(m_srcPoly[0].Y - m_normals[0].Y * delta)); + m_destPoly.Add(pt1); + pt1 = new IntPoint(Round(m_srcPoly[0].X + m_normals[0].X * delta), + Round(m_srcPoly[0].Y + m_normals[0].Y * delta)); + m_destPoly.Add(pt1); + } + else + { + k = 1; + m_sinA = 0; + if (node.m_endtype == EndType.etOpenSquare) + DoSquare(0, 1); + else + DoRound(0, 1); + } + m_destPolys.Add(m_destPoly); + } + } + } + //------------------------------------------------------------------------------ + + void OffsetPoint(int j, ref 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 (Math.Abs(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.Add(new 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.Add(new 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.Add(m_srcPoly[j]); + m_destPoly.Add(new 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 JoinType.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 JoinType.jtSquare: DoSquare(j, k); break; + case JoinType.jtRound: DoRound(j, k); break; + } + k = j; + } + //------------------------------------------------------------------------------ + + internal void DoSquare(int j, int k) + { + double dx = Math.Tan(Math.Atan2(m_sinA, + m_normals[k].X * m_normals[j].X + m_normals[k].Y * m_normals[j].Y) / 4); + m_destPoly.Add(new 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.Add(new 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)))); + } + //------------------------------------------------------------------------------ + + internal void DoMiter(int j, int k, double r) + { + double q = m_delta / r; + m_destPoly.Add(new 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))); + } + //------------------------------------------------------------------------------ + + internal void DoRound(int j, int k) + { + double a = Math.Atan2(m_sinA, + m_normals[k].X * m_normals[j].X + m_normals[k].Y * m_normals[j].Y); + int steps = Math.Max((int)Round(m_StepsPerRad * Math.Abs(a)), 1); + + double X = m_normals[k].X, Y = m_normals[k].Y, X2; + for (int i = 0; i < steps; ++i) + { + m_destPoly.Add(new 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.Add(new IntPoint( + Round(m_srcPoly[j].X + m_normals[j].X * m_delta), + Round(m_srcPoly[j].Y + m_normals[j].Y * m_delta))); + } + //------------------------------------------------------------------------------ + } + + class ClipperException : Exception + { + public ClipperException(string description) : base(description) { } + } + //------------------------------------------------------------------------------ + +} //end ClipperLib namespace diff --git a/src/UglyToad.PdfPig/Graphics/PdfPath.cs b/src/UglyToad.PdfPig/Graphics/PdfPath.cs index 8e0ec65a..f3a64430 100644 --- a/src/UglyToad.PdfPig/Graphics/PdfPath.cs +++ b/src/UglyToad.PdfPig/Graphics/PdfPath.cs @@ -23,47 +23,48 @@ public bool IsClipping { get; private set; } /// - /// + /// Returns true if the path is filled. /// public bool IsFilled { get; private set; } /// - /// + /// The fill color. /// - public IColor FillColor { get; set; } + public IColor FillColor { get; internal set; } /// - /// + /// Returns true if the path is stroked. /// public bool IsStroked { get; private set; } /// - /// + /// The stroke color. /// - public IColor StrokeColor { get; set; } + public IColor StrokeColor { get; internal set; } /// /// Thickness in user space units of path to be stroked. /// - public decimal LineWidth { get; set; } + public decimal LineWidth { get; internal set; } /// /// The pattern to be used for stroked lines. /// - public LineDashPattern? LineDashPattern { get; set; } + public LineDashPattern? LineDashPattern { get; internal set; } /// /// The cap style to be used for stroked lines. /// - public LineCapStyle LineCapStyle { get; set; } + public LineCapStyle LineCapStyle { get; internal set; } /// /// The join style to be used for stroked lines. /// - public LineJoinStyle LineJoinStyle { get; set; } + public LineJoinStyle LineJoinStyle { get; internal set; } /// - /// Set the clipping mode for this path. + /// Set the clipping mode for this path and IsClipping to true. + /// IsFilled and IsStroked flags will be set to false. /// public void SetClipping(FillingRule fillingRule) { @@ -74,7 +75,7 @@ } /// - /// Set the filling rule for this path. + /// Set the filling rule for this path and IsFilled to true. /// public void SetFilled(FillingRule fillingRule) { @@ -83,7 +84,7 @@ } /// - /// + /// Set IsStroked to true. /// public void SetStroked() { @@ -93,7 +94,7 @@ /// /// Create a clone with no Subpaths. /// - public PdfPath CloneEmpty() + internal PdfPath CloneEmpty() { PdfPath newPath = new PdfPath(); if (IsClipping) @@ -122,9 +123,9 @@ } /// - /// + /// Gets a which entirely contains the geometry of the defined path. /// - /// + /// For paths which don't define any geometry this returns . public PdfRectangle? GetBoundingRectangle() { if (this.Count == 0)