4632 lines
142 KiB
C#
4632 lines
142 KiB
C#
/*******************************************************************************
|
|
* *
|
|
* 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. *
|
|
* *
|
|
*******************************************************************************/
|
|
|
|
//use_int32: When enabled 32bit ints are used instead of 64bit ints. This
|
|
//improve performance but coordinate values are limited to the range +/- 46340
|
|
//#define use_int32
|
|
|
|
//use_xyz: adds a Z member to IntPoint. Adds a minor cost to performance.
|
|
//#define use_xyz
|
|
|
|
//use_lines: Enables open path clipping. Adds a very minor cost to performance.
|
|
#define use_lines
|
|
|
|
|
|
using System;
|
|
using System.Collections.Generic;
|
|
|
|
//using System.Text; //for Int128.AsString() & StringBuilder
|
|
//using System.IO; //debugging with streamReader & StreamWriter
|
|
//using System.Windows.Forms; //debugging to clipboard
|
|
|
|
namespace TGS.ClipperLib {
|
|
|
|
#if use_int32
|
|
using cInt = Int32;
|
|
|
|
|
|
#else
|
|
using cInt = Int64;
|
|
#endif
|
|
|
|
using Path = List<IntPoint>;
|
|
using Paths = List<List<IntPoint>>;
|
|
|
|
public 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
|
|
//------------------------------------------------------------------------------
|
|
|
|
public class PolyTree : PolyNode {
|
|
internal List<PolyNode> m_AllPolys = new List<PolyNode> ();
|
|
|
|
//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;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
public class PolyNode {
|
|
internal PolyNode m_Parent;
|
|
internal Path m_polygon = new Path ();
|
|
internal int m_Index;
|
|
internal JoinType m_jointype;
|
|
internal EndType m_endtype;
|
|
internal List<PolyNode> m_Childs = new List<PolyNode> ();
|
|
|
|
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 Path 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<PolyNode> 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((Int64)9223372036854775807); //ie 2^63 -1
|
|
// Int128 val2((Int64)9223372036854775807);
|
|
// Int128 val3 = val1 * val2;
|
|
// val3.ToString => "85070591730234615847396907784232501249" (8.5e+37)
|
|
//------------------------------------------------------------------------------
|
|
|
|
internal struct Int128 {
|
|
private Int64 hi;
|
|
private UInt64 lo;
|
|
|
|
public Int128 (Int64 _lo) {
|
|
lo = (UInt64)_lo;
|
|
if (_lo < 0)
|
|
hi = -1;
|
|
else
|
|
hi = 0;
|
|
}
|
|
|
|
public Int128 (Int64 _hi, UInt64 _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 == null || (object)val2 == 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 (System.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 (Int64 lhs, Int64 rhs) {
|
|
bool negate = (lhs < 0) != (rhs < 0);
|
|
if (lhs < 0)
|
|
lhs = -lhs;
|
|
if (rhs < 0)
|
|
rhs = -rhs;
|
|
UInt64 int1Hi = (UInt64)lhs >> 32;
|
|
UInt64 int1Lo = (UInt64)lhs & 0xFFFFFFFF;
|
|
UInt64 int2Hi = (UInt64)rhs >> 32;
|
|
UInt64 int2Lo = (UInt64)rhs & 0xFFFFFFFF;
|
|
|
|
//nb: see comments in clipper.pas
|
|
UInt64 a = int1Hi * int2Hi;
|
|
UInt64 b = int1Lo * int2Lo;
|
|
UInt64 c = int1Hi * int2Lo + int1Lo * int2Hi;
|
|
|
|
UInt64 lo;
|
|
Int64 hi;
|
|
hi = (Int64)(a + (c >> 32));
|
|
|
|
unchecked {
|
|
lo = (c << 32) + b;
|
|
}
|
|
if (lo < b)
|
|
hi++;
|
|
Int128 result = new Int128 (hi, lo);
|
|
return negate ? -result : result;
|
|
}
|
|
|
|
};
|
|
|
|
//------------------------------------------------------------------------------
|
|
//------------------------------------------------------------------------------
|
|
|
|
public struct IntPoint {
|
|
public cInt X;
|
|
public cInt Y;
|
|
#if use_xyz
|
|
public cInt Z;
|
|
|
|
public IntPoint(cInt x, cInt y, cInt z = 0)
|
|
{
|
|
this.X = x; this.Y = y; this.Z = z;
|
|
}
|
|
|
|
public IntPoint(double x, double y, double z = 0)
|
|
{
|
|
this.X = (cInt)x; this.Y = (cInt)y; this.Z = (cInt)z;
|
|
}
|
|
|
|
public IntPoint(DoublePoint dp)
|
|
{
|
|
this.X = (cInt)dp.X; this.Y = (cInt)dp.Y; this.Z = 0;
|
|
}
|
|
|
|
public IntPoint(IntPoint pt)
|
|
{
|
|
this.X = pt.X; this.Y = pt.Y; this.Z = pt.Z;
|
|
}
|
|
|
|
|
|
#else
|
|
public IntPoint (cInt X, cInt Y) {
|
|
this.X = X;
|
|
this.Y = Y;
|
|
}
|
|
|
|
public IntPoint (float x, float y) {
|
|
this.X = (cInt)x;
|
|
this.Y = (cInt)y;
|
|
}
|
|
|
|
public IntPoint (double x, double y) {
|
|
this.X = (cInt)x;
|
|
this.Y = (cInt)y;
|
|
}
|
|
|
|
public IntPoint (IntPoint pt) {
|
|
this.X = pt.X;
|
|
this.Y = pt.Y;
|
|
}
|
|
#endif
|
|
|
|
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) {
|
|
IntPoint a = (IntPoint)obj;
|
|
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
|
|
|
|
public struct IntRect {
|
|
public cInt left;
|
|
public cInt top;
|
|
public cInt right;
|
|
public cInt bottom;
|
|
|
|
public IntRect (cInt l, cInt t, cInt r, cInt 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;
|
|
}
|
|
}
|
|
|
|
public enum ClipType {
|
|
ctIntersection,
|
|
ctUnion,
|
|
ctDifference,
|
|
ctXor}
|
|
|
|
;
|
|
|
|
public enum PolyType {
|
|
ptSubject,
|
|
ptClip}
|
|
|
|
;
|
|
|
|
//By far the most widely used winding rules for polygon filling are
|
|
//EvenOdd & NonZero (GDI, GDI+, XLib, OpenGL, Cairo, AGG, Quartz, SVG, Gr32)
|
|
//Others rules include Positive, Negative and ABS_GTR_EQ_TWO (only in OpenGL)
|
|
//see http://glprogramming.com/red/chapter11.html
|
|
public enum PolyFillType {
|
|
pftEvenOdd,
|
|
pftNonZero,
|
|
pftPositive,
|
|
pftNegative}
|
|
|
|
;
|
|
|
|
public enum JoinType {
|
|
jtSquare,
|
|
jtRound,
|
|
jtMiter}
|
|
|
|
;
|
|
|
|
public 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;
|
|
};
|
|
|
|
public class IntersectNode {
|
|
internal TEdge Edge1;
|
|
internal TEdge Edge2;
|
|
internal IntPoint Pt;
|
|
};
|
|
|
|
public class MyIntersectNodeSort : IComparer<IntersectNode> {
|
|
public int Compare (IntersectNode node1, IntersectNode node2) {
|
|
cInt 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 cInt Y;
|
|
internal TEdge LeftBound;
|
|
internal TEdge RightBound;
|
|
internal LocalMinima Next;
|
|
};
|
|
|
|
internal class Scanbeam {
|
|
internal cInt Y;
|
|
internal Scanbeam Next;
|
|
};
|
|
|
|
internal class Maxima {
|
|
internal cInt 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;
|
|
};
|
|
|
|
public 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 near_zero (double val) {
|
|
return (val > -tolerance) && (val < tolerance);
|
|
}
|
|
|
|
#if use_int32
|
|
public const cInt loRange = 0x7FFF;
|
|
public const cInt hiRange = 0x7FFF;
|
|
|
|
|
|
#else
|
|
public const cInt loRange = 0x3FFFFFFF;
|
|
public const cInt hiRange = 0x3FFFFFFFFFFFFFFFL;
|
|
#endif
|
|
|
|
internal LocalMinima m_MinimaList;
|
|
internal LocalMinima m_CurrentLM;
|
|
internal List<List<TEdge>> m_edges = new List<List<TEdge>> ();
|
|
internal Scanbeam m_Scanbeam;
|
|
internal List<OutRec> m_PolyOuts;
|
|
internal TEdge m_ActiveEdges;
|
|
internal bool m_UseFullRange;
|
|
internal bool m_HasOpenPaths;
|
|
|
|
//------------------------------------------------------------------------------
|
|
|
|
public bool PreserveCollinear {
|
|
get;
|
|
set;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public void Swap (ref cInt val1, ref cInt val2) {
|
|
cInt 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 (cInt)(e1.Delta.Y) * (e2.Delta.X) ==
|
|
(cInt)(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
|
|
(cInt)(pt1.Y - pt2.Y) * (pt2.X - pt3.X) - (cInt)(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
|
|
(cInt)(pt1.Y - pt2.Y) * (pt3.X - pt4.X) - (cInt)(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 ();
|
|
locMin.Next = null;
|
|
locMin.Y = E.Bot.Y;
|
|
locMin.LeftBound = null;
|
|
locMin.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 (Path pg, PolyType polyType, bool Closed) {
|
|
#if use_lines
|
|
if (!Closed && polyType == PolyType.ptClip)
|
|
throw new ClipperException ("AddPath: Open paths must be subject.");
|
|
#else
|
|
if (!Closed)
|
|
throw new ClipperException("AddPath: Open paths have been disabled.");
|
|
#endif
|
|
|
|
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<TEdge> edges = new List<TEdge> (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 ();
|
|
locMin.Next = null;
|
|
locMin.Y = E.Bot.Y;
|
|
locMin.LeftBound = null;
|
|
locMin.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 ();
|
|
locMin.Next = null;
|
|
locMin.Y = E.Bot.Y;
|
|
if (E.Dx < E.Prev.Dx) {
|
|
locMin.LeftBound = E.Prev;
|
|
locMin.RightBound = E;
|
|
leftBoundIsForward = false; //Q.nextInLML = Q.prev
|
|
} else {
|
|
locMin.LeftBound = E;
|
|
locMin.RightBound = E.Prev;
|
|
leftBoundIsForward = true; //Q.nextInLML = Q.next
|
|
}
|
|
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 (Paths 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 Boolean PopLocalMinima (cInt 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);
|
|
#if use_xyz
|
|
Swap(ref e.Top.Z, ref e.Bot.Z);
|
|
#endif
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
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 (Paths 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 ();
|
|
result.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 (cInt Y) {
|
|
//single-linked list: sorted descending, ignoring dups.
|
|
if (m_Scanbeam == null) {
|
|
m_Scanbeam = new Scanbeam ();
|
|
m_Scanbeam.Next = null;
|
|
m_Scanbeam.Y = Y;
|
|
} else if (Y > m_Scanbeam.Y) {
|
|
Scanbeam newSb = new Scanbeam ();
|
|
newSb.Y = Y;
|
|
newSb.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 ();
|
|
newSb.Y = Y;
|
|
newSb.Next = sb2.Next;
|
|
sb2.Next = newSb;
|
|
}
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
internal Boolean PopScanbeam (out cInt Y) {
|
|
if (m_Scanbeam == null) {
|
|
Y = 0;
|
|
return false;
|
|
}
|
|
Y = m_Scanbeam.Y;
|
|
m_Scanbeam = m_Scanbeam.Next;
|
|
return true;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
internal Boolean LocalMinimaPending () {
|
|
return (m_CurrentLM != null);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
internal OutRec CreateOutRec () {
|
|
OutRec result = new OutRec ();
|
|
result.Idx = Unassigned;
|
|
result.IsHole = false;
|
|
result.IsOpen = false;
|
|
result.FirstLeft = null;
|
|
result.Pts = null;
|
|
result.BottomPt = null;
|
|
result.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
|
|
|
|
public partial 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 List<IntersectNode> m_IntersectList;
|
|
IComparer<IntersectNode> m_IntersectNodeComparer;
|
|
private bool m_ExecuteLocked;
|
|
private PolyFillType m_ClipFillType;
|
|
private PolyFillType m_SubjFillType;
|
|
private List<Join> m_Joins;
|
|
private List<Join> m_GhostJoins;
|
|
private bool m_UsingPolyTree;
|
|
#if use_xyz
|
|
public delegate void ZFillCallback(IntPoint bot1, IntPoint top1,
|
|
IntPoint bot2, IntPoint top2, ref IntPoint pt);
|
|
public ZFillCallback ZFillFunction { get; set; }
|
|
#endif
|
|
public Clipper (int InitOptions = 0) : base () { //constructor
|
|
m_Scanbeam = null;
|
|
m_Maxima = null;
|
|
m_ActiveEdges = null;
|
|
m_SortedEdges = null;
|
|
m_IntersectList = new List<IntersectNode> ();
|
|
m_IntersectNodeComparer = new MyIntersectNodeSort ();
|
|
m_ExecuteLocked = false;
|
|
m_UsingPolyTree = false;
|
|
m_PolyOuts = new List<OutRec> ();
|
|
m_Joins = new List<Join> ();
|
|
m_GhostJoins = new List<Join> ();
|
|
ReverseSolution = (ioReverseSolution & InitOptions) != 0;
|
|
StrictlySimple = (ioStrictlySimple & InitOptions) != 0;
|
|
PreserveCollinear = (ioPreserveCollinear & InitOptions) != 0;
|
|
#if use_xyz
|
|
ZFillFunction = null;
|
|
#endif
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
private void InsertMaxima (cInt X) {
|
|
//double-linked list: sorted ascending, ignoring dups.
|
|
Maxima newMax = new Maxima ();
|
|
newMax.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, Paths 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, Paths 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;
|
|
|
|
cInt botY, topY;
|
|
if (!PopScanbeam (out botY))
|
|
return false;
|
|
InsertLocalMinimaIntoAEL (botY);
|
|
while (PopScanbeam (out 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 ();
|
|
j.OutPt1 = Op1;
|
|
j.OutPt2 = Op2;
|
|
j.OffPt = OffPt;
|
|
m_Joins.Add (j);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
private void AddGhostJoin (OutPt Op, IntPoint OffPt) {
|
|
Join j = new Join ();
|
|
j.OutPt1 = Op;
|
|
j.OffPt = OffPt;
|
|
m_GhostJoins.Add (j);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
#if use_xyz
|
|
internal void SetZ(ref IntPoint pt, TEdge e1, TEdge e2)
|
|
{
|
|
if (pt.Z != 0 || ZFillFunction == null) return;
|
|
else if (pt == e1.Bot) pt.Z = e1.Bot.Z;
|
|
else if (pt == e1.Top) pt.Z = e1.Top.Z;
|
|
else if (pt == e2.Bot) pt.Z = e2.Bot.Z;
|
|
else if (pt == e2.Top) pt.Z = e2.Top.Z;
|
|
else ZFillFunction(e1.Bot, e1.Top, e2.Bot, e2.Top, ref pt);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
#endif
|
|
|
|
private void InsertLocalMinimaIntoAEL (cInt botY) {
|
|
LocalMinima lm;
|
|
while (PopLocalMinima (botY, out 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) {
|
|
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;
|
|
case PolyFillType.pftPositive:
|
|
if (edge.WindCnt != 1)
|
|
return false;
|
|
break;
|
|
default: //PolyFillType.pftNegative
|
|
if (edge.WindCnt != -1)
|
|
return false;
|
|
break;
|
|
}
|
|
|
|
switch (m_ClipType) {
|
|
case ClipType.ctIntersection:
|
|
switch (pft2) {
|
|
case PolyFillType.pftEvenOdd:
|
|
case PolyFillType.pftNonZero:
|
|
return (edge.WindCnt2 != 0);
|
|
case PolyFillType.pftPositive:
|
|
return (edge.WindCnt2 > 0);
|
|
default:
|
|
return (edge.WindCnt2 < 0);
|
|
}
|
|
case ClipType.ctUnion:
|
|
switch (pft2) {
|
|
case PolyFillType.pftEvenOdd:
|
|
case PolyFillType.pftNonZero:
|
|
return (edge.WindCnt2 == 0);
|
|
case PolyFillType.pftPositive:
|
|
return (edge.WindCnt2 <= 0);
|
|
default:
|
|
return (edge.WindCnt2 >= 0);
|
|
}
|
|
case ClipType.ctDifference:
|
|
if (edge.PolyTyp == PolyType.ptSubject)
|
|
switch (pft2) {
|
|
case PolyFillType.pftEvenOdd:
|
|
case PolyFillType.pftNonZero:
|
|
return (edge.WindCnt2 == 0);
|
|
case PolyFillType.pftPositive:
|
|
return (edge.WindCnt2 <= 0);
|
|
default:
|
|
return (edge.WindCnt2 >= 0);
|
|
}
|
|
else
|
|
switch (pft2) {
|
|
case PolyFillType.pftEvenOdd:
|
|
case PolyFillType.pftNonZero:
|
|
return (edge.WindCnt2 != 0);
|
|
case PolyFillType.pftPositive:
|
|
return (edge.WindCnt2 > 0);
|
|
default:
|
|
return (edge.WindCnt2 < 0);
|
|
}
|
|
case ClipType.ctXor:
|
|
if (edge.WindDelta == 0) //XOr always contributing unless open
|
|
switch (pft2) {
|
|
case PolyFillType.pftEvenOdd:
|
|
case PolyFillType.pftNonZero:
|
|
return (edge.WindCnt2 == 0);
|
|
case PolyFillType.pftPositive:
|
|
return (edge.WindCnt2 <= 0);
|
|
default:
|
|
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;
|
|
pft = (edge.PolyTyp == PolyType.ptSubject ? m_SubjFillType : m_ClipFillType);
|
|
if (edge.WindDelta == 0)
|
|
edge.WindCnt = (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 Boolean 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) {
|
|
cInt xPrev = TopX (prevE, pt.Y);
|
|
cInt 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 ();
|
|
newOp.Idx = outRec.Idx;
|
|
newOp.Pt = pt;
|
|
newOp.Next = op;
|
|
newOp.Prev = op.Prev;
|
|
newOp.Prev.Next = newOp;
|
|
op.Prev = newOp;
|
|
if (ToFront)
|
|
outRec.Pts = newOp;
|
|
return newOp;
|
|
}
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
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 (cInt seg1a, cInt seg1b, cInt seg2a, cInt 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);
|
|
|
|
#if use_xyz
|
|
SetZ(ref pt, e1, e2);
|
|
#endif
|
|
|
|
#if use_lines
|
|
//if either edge is on an OPEN path ...
|
|
if (e1.WindDelta == 0 || e2.WindDelta == 0) {
|
|
//ignore subject-subject open path intersections UNLESS they
|
|
//are both open paths, AND they are both 'contributing maximas' ...
|
|
if (e1.WindDelta == 0 && e2.WindDelta == 0)
|
|
return;
|
|
//if intersecting a subj line with a subj poly ...
|
|
else if (e1.PolyTyp == e2.PolyTyp &&
|
|
e1.WindDelta != e2.WindDelta && m_ClipType == 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;
|
|
}
|
|
#endif
|
|
|
|
//update winding counts...
|
|
//assumes that e1 will be to the Right of e2 ABOVE the intersection
|
|
if (e1.PolyTyp == e2.PolyTyp) {
|
|
if (IsEvenOddFillType (e1)) {
|
|
int oldE1WindCnt = e1.WindCnt;
|
|
e1.WindCnt = e2.WindCnt;
|
|
e2.WindCnt = oldE1WindCnt;
|
|
} else {
|
|
if (e1.WindCnt + e2.WindDelta == 0)
|
|
e1.WindCnt = -e1.WindCnt;
|
|
else
|
|
e1.WindCnt += e2.WindDelta;
|
|
if (e2.WindCnt - e1.WindDelta == 0)
|
|
e2.WindCnt = -e2.WindCnt;
|
|
else
|
|
e2.WindCnt -= e1.WindDelta;
|
|
}
|
|
} else {
|
|
if (!IsEvenOddFillType (e2))
|
|
e1.WindCnt2 += e2.WindDelta;
|
|
else
|
|
e1.WindCnt2 = (e1.WindCnt2 == 0) ? 1 : 0;
|
|
if (!IsEvenOddFillType (e1))
|
|
e2.WindCnt2 -= e1.WindDelta;
|
|
else
|
|
e2.WindCnt2 = (e2.WindCnt2 == 0) ? 1 : 0;
|
|
}
|
|
|
|
PolyFillType e1FillType, e2FillType, e1FillType2, e2FillType2;
|
|
if (e1.PolyTyp == 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, e2Wc;
|
|
switch (e1FillType) {
|
|
case PolyFillType.pftPositive:
|
|
e1Wc = e1.WindCnt;
|
|
break;
|
|
case PolyFillType.pftNegative:
|
|
e1Wc = -e1.WindCnt;
|
|
break;
|
|
default:
|
|
e1Wc = Math.Abs (e1.WindCnt);
|
|
break;
|
|
}
|
|
switch (e2FillType) {
|
|
case PolyFillType.pftPositive:
|
|
e2Wc = e2.WindCnt;
|
|
break;
|
|
case PolyFillType.pftNegative:
|
|
e2Wc = -e2.WindCnt;
|
|
break;
|
|
default:
|
|
e2Wc = Math.Abs (e2.WindCnt);
|
|
break;
|
|
}
|
|
|
|
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 ...
|
|
cInt e1Wc2, e2Wc2;
|
|
switch (e1FillType2) {
|
|
case PolyFillType.pftPositive:
|
|
e1Wc2 = e1.WindCnt2;
|
|
break;
|
|
case PolyFillType.pftNegative:
|
|
e1Wc2 = -e1.WindCnt2;
|
|
break;
|
|
default:
|
|
e1Wc2 = Math.Abs (e1.WindCnt2);
|
|
break;
|
|
}
|
|
switch (e2FillType2) {
|
|
case PolyFillType.pftPositive:
|
|
e2Wc2 = e2.WindCnt2;
|
|
break;
|
|
case PolyFillType.pftNegative:
|
|
e2Wc2 = -e2.WindCnt2;
|
|
break;
|
|
default:
|
|
e2Wc2 = Math.Abs (e2.WindCnt2);
|
|
break;
|
|
}
|
|
|
|
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 DeleteFromSEL (TEdge e) {
|
|
TEdge SelPrev = e.PrevInSEL;
|
|
TEdge SelNext = e.NextInSEL;
|
|
if (SelPrev == null && SelNext == null && (e != m_SortedEdges))
|
|
return; //already deleted
|
|
if (SelPrev != null)
|
|
SelPrev.NextInSEL = SelNext;
|
|
else
|
|
m_SortedEdges = SelNext;
|
|
if (SelNext != null)
|
|
SelNext.PrevInSEL = SelPrev;
|
|
e.NextInSEL = null;
|
|
e.PrevInSEL = null;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
private void ProcessHorizontals () {
|
|
TEdge horzEdge; //m_SortedEdges;
|
|
while (PopEdgeFromSEL (out horzEdge))
|
|
ProcessHorizontal (horzEdge);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
void GetHorzDirection (TEdge HorzEdge, out Direction Dir, out cInt Left, out cInt 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) {
|
|
Direction dir;
|
|
cInt horzLeft, horzRight;
|
|
bool IsOpen = horzEdge.WindDelta == 0;
|
|
|
|
GetHorzDirection (horzEdge, out dir, out horzLeft, out 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
|
|
#if use_xyz
|
|
if (dir == Direction.dLeftToRight) SetZ(ref e.Curr, horzEdge, e);
|
|
else SetZ(ref e.Curr, e, horzEdge);
|
|
#endif
|
|
|
|
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 IsMinima (TEdge e) {
|
|
return e != null && (e.Prev.NextInLML != e) && (e.Next.NextInLML != e);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
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 (cInt 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 (cInt 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;
|
|
IntPoint pt;
|
|
if (e.Curr.X > eNext.Curr.X) {
|
|
IntersectPoint (e, eNext, out pt);
|
|
if (pt.Y < topY)
|
|
pt = new IntPoint (TopX (e, topY), topY);
|
|
IntersectNode newNode = new IntersectNode ();
|
|
newNode.Edge1 = e;
|
|
newNode.Edge2 = eNext;
|
|
newNode.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 static int IntersectNodeSort (IntersectNode node1, IntersectNode node2) {
|
|
//the following typecast is safe because the differences in Pt.Y will
|
|
//be limited to the height of the scanbeam.
|
|
return (int)(node2.Pt.Y - node1.Pt.Y);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
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 cInt Round (double value) {
|
|
return value < 0 ? (cInt)(value - 0.5) : (cInt)(value + 0.5);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
private static cInt TopX (TEdge edge, cInt 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 (cInt 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;
|
|
#if use_xyz
|
|
if (e.Top.Y == topY) e.Curr.Z = e.Top.Z;
|
|
else if (e.Bot.Y == topY) e.Curr.Z = e.Bot.Z;
|
|
else e.Curr.Z = 0;
|
|
#endif
|
|
}
|
|
//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);
|
|
#if use_xyz
|
|
SetZ(ref ip, ePrev, e);
|
|
#endif
|
|
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);
|
|
}
|
|
#if use_lines
|
|
else if (e.WindDelta == 0) {
|
|
if (e.OutIdx >= 0) {
|
|
AddOutPt (e, e.Top);
|
|
e.OutIdx = Unassigned;
|
|
}
|
|
DeleteFromAEL (e);
|
|
|
|
if (eMaxPair.OutIdx >= 0) {
|
|
AddOutPt (eMaxPair, e.Top);
|
|
eMaxPair.OutIdx = Unassigned;
|
|
}
|
|
DeleteFromAEL (eMaxPair);
|
|
}
|
|
#endif
|
|
else
|
|
throw new ClipperException ("DoMaxima error");
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static void ReversePaths (Paths polys) {
|
|
foreach (var poly in polys) {
|
|
poly.Reverse ();
|
|
}
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static bool Orientation (Path 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 (Paths 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;
|
|
Path pg = new Path (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 ();
|
|
result.Pt = outPt.Pt;
|
|
result.Idx = outPt.Idx;
|
|
if (InsertAfter) {
|
|
result.Next = outPt.Next;
|
|
result.Prev = outPt;
|
|
outPt.Next.Prev = result;
|
|
outPt.Next = result;
|
|
} else {
|
|
result.Prev = outPt.Prev;
|
|
result.Next = outPt;
|
|
outPt.Prev.Next = result;
|
|
outPt.Prev = result;
|
|
}
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
bool GetOverlap (cInt a1, cInt a2, cInt b1, cInt b2, out cInt Left, out cInt 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'
|
|
|
|
cInt Left, Right;
|
|
//Op1 -. Op1b & Op2 -. Op2b are the extremites of the horizontal edges
|
|
if (!GetOverlap (op1.Pt.X, op1b.Pt.X, op2.Pt.X, op2b.Pt.X, out Left, out 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;
|
|
}
|
|
}
|
|
}
|
|
//----------------------------------------------------------------------
|
|
|
|
public static int PointInPolygon (IntPoint pt, Path path) {
|
|
//returns 0 if false, +1 if true, -1 if pt ON polygon boundary
|
|
//See "The Point in Polygon Problem for Arbitrary Polygons" by Hormann & Agathos
|
|
//http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.88.5498&rep=rep1&type=pdf
|
|
int 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;
|
|
cInt ptx = pt.X, pty = pt.Y;
|
|
cInt poly0x = op.Pt.X, poly0y = op.Pt.Y;
|
|
do {
|
|
op = op.Next;
|
|
cInt 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 (Path poly) {
|
|
int cnt = (int)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 = 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
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static Paths SimplifyPolygon (Path poly,
|
|
PolyFillType fillType = PolyFillType.pftEvenOdd) {
|
|
Paths result = new Paths ();
|
|
Clipper c = new Clipper ();
|
|
c.StrictlySimple = true;
|
|
c.AddPath (poly, PolyType.ptSubject, true);
|
|
c.Execute (ClipType.ctUnion, result, fillType, fillType);
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static Paths SimplifyPolygons (Paths polys,
|
|
PolyFillType fillType = PolyFillType.pftEvenOdd) {
|
|
Paths result = new Paths ();
|
|
Clipper c = new Clipper ();
|
|
c.StrictlySimple = true;
|
|
c.AddPaths (polys, PolyType.ptSubject, true);
|
|
c.Execute (ClipType.ctUnion, result, fillType, fillType);
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
private static double DistanceSqrd (IntPoint pt1, IntPoint pt2) {
|
|
double dx = ((double)pt1.X - pt2.X);
|
|
double dy = ((double)pt1.Y - pt2.Y);
|
|
return (dx * dx + dy * dy);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
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);
|
|
}
|
|
//---------------------------------------------------------------------------
|
|
|
|
private static bool SlopesNearCollinear (IntPoint pt1,
|
|
IntPoint pt2, IntPoint pt3, double distSqrd) {
|
|
//this function is more accurate when the point that's GEOMETRICALLY
|
|
//between the other 2 points is the one that's tested for distance.
|
|
//nb: with 'spikes', either pt1 or pt3 is geometrically between the other pts
|
|
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;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static Path CleanPolygon (Path 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 Path ();
|
|
|
|
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;
|
|
Path result = new Path (cnt);
|
|
for (int i = 0; i < cnt; ++i) {
|
|
result.Add (op.Pt);
|
|
op = op.Next;
|
|
}
|
|
outPts = null;
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static Paths CleanPolygons (Paths polys,
|
|
double distance = 1.415) {
|
|
Paths result = new Paths (polys.Count);
|
|
for (int i = 0; i < polys.Count; i++)
|
|
result.Add (CleanPolygon (polys [i], distance));
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
internal static Paths Minkowski (Path pattern, Path path, bool IsSum, bool IsClosed) {
|
|
int delta = (IsClosed ? 1 : 0);
|
|
int polyCnt = pattern.Count;
|
|
int pathCnt = path.Count;
|
|
Paths result = new Paths (pathCnt);
|
|
if (IsSum)
|
|
for (int i = 0; i < pathCnt; i++) {
|
|
Path p = new Path (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++) {
|
|
Path p = new Path (polyCnt);
|
|
foreach (IntPoint ip in pattern)
|
|
p.Add (new IntPoint (path [i].X - ip.X, path [i].Y - ip.Y));
|
|
result.Add (p);
|
|
}
|
|
|
|
Paths quads = new Paths ((pathCnt + delta) * (polyCnt + 1));
|
|
for (int i = 0; i < pathCnt - 1 + delta; i++)
|
|
for (int j = 0; j < polyCnt; j++) {
|
|
Path quad = new Path (4);
|
|
quad.Add (result [i % pathCnt] [j % polyCnt]);
|
|
quad.Add (result [(i + 1) % pathCnt] [j % polyCnt]);
|
|
quad.Add (result [(i + 1) % pathCnt] [(j + 1) % polyCnt]);
|
|
quad.Add (result [i % pathCnt] [(j + 1) % polyCnt]);
|
|
if (!Orientation (quad))
|
|
quad.Reverse ();
|
|
quads.Add (quad);
|
|
}
|
|
return quads;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public static Paths MinkowskiSum (Path pattern, Path path, bool pathIsClosed) {
|
|
Paths 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 Path TranslatePath (Path path, IntPoint delta) {
|
|
Path outPath = new Path (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 Paths MinkowskiSum (Path pattern, Paths paths, bool pathIsClosed) {
|
|
Paths solution = new Paths ();
|
|
Clipper c = new Clipper ();
|
|
for (int i = 0; i < paths.Count; ++i) {
|
|
Paths tmp = Minkowski (pattern, paths [i], true, pathIsClosed);
|
|
c.AddPaths (tmp, PolyType.ptSubject, true);
|
|
if (pathIsClosed) {
|
|
Path 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 Paths MinkowskiDiff (Path poly1, Path poly2) {
|
|
Paths 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 Paths PolyTreeToPaths (PolyTree polytree) {
|
|
|
|
Paths result = new Paths ();
|
|
result.Capacity = polytree.Total;
|
|
AddPolyNodeToPaths (polytree, NodeType.ntAny, result);
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
internal static void AddPolyNodeToPaths (PolyNode polynode, NodeType nt, Paths 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 Paths OpenPathsFromPolyTree (PolyTree polytree) {
|
|
Paths result = new Paths ();
|
|
result.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 Paths ClosedPathsFromPolyTree (PolyTree polytree) {
|
|
Paths result = new Paths ();
|
|
result.Capacity = polytree.Total;
|
|
AddPolyNodeToPaths (polytree, NodeType.ntClosed, result);
|
|
return result;
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
}
|
|
//end Clipper
|
|
|
|
public class ClipperOffset {
|
|
private Paths m_destPolys;
|
|
private Path m_srcPoly;
|
|
private Path m_destPoly;
|
|
private List<DoublePoint> m_normals = new List<DoublePoint> ();
|
|
private double m_delta, m_sinA, m_sin, m_cos;
|
|
private double m_miterLim, m_StepsPerRad;
|
|
|
|
private IntPoint m_lowest;
|
|
private 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 cInt Round (double value) {
|
|
return value < 0 ? (cInt)(value - 0.5) : (cInt)(value + 0.5);
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public void AddPath (Path path, JoinType joinType, EndType endType) {
|
|
int highI = path.Count - 1;
|
|
if (highI < 0)
|
|
return;
|
|
PolyNode newNode = new PolyNode ();
|
|
newNode.m_jointype = joinType;
|
|
newNode.m_endtype = endType;
|
|
|
|
//strip duplicate points from path and also get index to the lowest point ...
|
|
if (endType == 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 (Paths paths, JoinType joinType, EndType endType) {
|
|
foreach (Path 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 Paths ();
|
|
m_delta = delta;
|
|
|
|
//if Zero offset, just copy any CLOSED polygons to m_p and return ...
|
|
if (ClipperBase.near_zero (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 Path ();
|
|
|
|
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 Path ();
|
|
//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 ((cInt)Round (m_srcPoly [j].X + m_normals [j].X *
|
|
delta), (cInt)Round (m_srcPoly [j].Y + m_normals [j].Y * delta));
|
|
m_destPoly.Add (pt1);
|
|
pt1 = new IntPoint ((cInt)Round (m_srcPoly [j].X - m_normals [j].X *
|
|
delta), (cInt)Round (m_srcPoly [j].Y - m_normals [j].Y * delta));
|
|
m_destPoly.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 ((cInt)Round (m_srcPoly [0].X - m_normals [0].X * delta),
|
|
(cInt)Round (m_srcPoly [0].Y - m_normals [0].Y * delta));
|
|
m_destPoly.Add (pt1);
|
|
pt1 = new IntPoint ((cInt)Round (m_srcPoly [0].X + m_normals [0].X * delta),
|
|
(cInt)Round (m_srcPoly [0].Y + m_normals [0].Y * delta));
|
|
m_destPoly.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);
|
|
}
|
|
}
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public void Execute (ref Paths solution, double delta) {
|
|
solution.Clear ();
|
|
FixOrientations ();
|
|
DoOffset (delta);
|
|
//now clean up 'corners' ...
|
|
Clipper clpr = new Clipper ();
|
|
clpr.AddPaths (m_destPolys, PolyType.ptSubject, true);
|
|
if (delta > 0) {
|
|
clpr.Execute (ClipType.ctUnion, solution,
|
|
PolyFillType.pftPositive, PolyFillType.pftPositive);
|
|
} else {
|
|
IntRect r = Clipper.GetBounds (m_destPolys);
|
|
Path outer = new Path (4);
|
|
|
|
outer.Add (new IntPoint (r.left - 10, r.bottom + 10));
|
|
outer.Add (new IntPoint (r.right + 10, r.bottom + 10));
|
|
outer.Add (new IntPoint (r.right + 10, r.top - 10));
|
|
outer.Add (new IntPoint (r.left - 10, r.top - 10));
|
|
|
|
clpr.AddPath (outer, PolyType.ptSubject, true);
|
|
clpr.ReverseSolution = true;
|
|
clpr.Execute (ClipType.ctUnion, solution, PolyFillType.pftNegative, PolyFillType.pftNegative);
|
|
if (solution.Count > 0)
|
|
solution.RemoveAt (0);
|
|
}
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
public void Execute (ref PolyTree solution, double delta) {
|
|
solution.Clear ();
|
|
FixOrientations ();
|
|
DoOffset (delta);
|
|
|
|
//now clean up 'corners' ...
|
|
Clipper clpr = new Clipper ();
|
|
clpr.AddPaths (m_destPolys, PolyType.ptSubject, true);
|
|
if (delta > 0) {
|
|
clpr.Execute (ClipType.ctUnion, solution,
|
|
PolyFillType.pftPositive, PolyFillType.pftPositive);
|
|
} else {
|
|
IntRect r = Clipper.GetBounds (m_destPolys);
|
|
Path outer = new Path (4);
|
|
|
|
outer.Add (new IntPoint (r.left - 10, r.bottom + 10));
|
|
outer.Add (new IntPoint (r.right + 10, r.bottom + 10));
|
|
outer.Add (new IntPoint (r.right + 10, r.top - 10));
|
|
outer.Add (new IntPoint (r.left - 10, r.top - 10));
|
|
|
|
clpr.AddPath (outer, PolyType.ptSubject, true);
|
|
clpr.ReverseSolution = true;
|
|
clpr.Execute (ClipType.ctUnion, solution, PolyFillType.pftNegative, PolyFillType.pftNegative);
|
|
//remove the outer PolyNode rectangle ...
|
|
if (solution.ChildCount == 1 && solution.Childs [0].ChildCount > 0) {
|
|
PolyNode outerNode = solution.Childs [0];
|
|
solution.Childs.Capacity = outerNode.ChildCount;
|
|
solution.Childs [0] = outerNode.Childs [0];
|
|
solution.Childs [0].m_Parent = solution;
|
|
for (int i = 1; i < outerNode.ChildCount; i++)
|
|
solution.AddChild (outerNode.Childs [i]);
|
|
} else
|
|
solution.Clear ();
|
|
}
|
|
}
|
|
//------------------------------------------------------------------------------
|
|
|
|
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
|