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5024 lines
185 KiB
5024 lines
185 KiB
/******************************************************************************* |
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* * |
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* Author : Angus Johnson * |
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* Version : 6.4.2 * |
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* Date : 27 February 2017 * |
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* Website : http://www.angusj.com * |
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* Copyright : Angus Johnson 2010-2017 * |
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* * |
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* License: * |
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* Use, modification & distribution is subject to Boost Software License Ver 1. * |
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* http://www.boost.org/LICENSE_1_0.txt * |
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* * |
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* Attributions: * |
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* The code in this library is an extension of Bala Vatti's clipping algorithm: * |
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* "A generic solution to polygon clipping" * |
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* Communications of the ACM, Vol 35, Issue 7 (July 1992) pp 56-63. * |
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* http://portal.acm.org/citation.cfm?id=129906 * |
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* * |
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* Computer graphics and geometric modeling: implementation and algorithms * |
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* By Max K. Agoston * |
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* Springer; 1 edition (January 4, 2005) * |
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* http://books.google.com/books?q=vatti+clipping+agoston * |
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* * |
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* See also: * |
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* "Polygon Offsetting by Computing Winding Numbers" * |
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* Paper no. DETC2005-85513 pp. 565-575 * |
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* ASME 2005 International Design Engineering Technical Conferences * |
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* and Computers and Information in Engineering Conference (IDETC/CIE2005) * |
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* September 24-28, 2005 , Long Beach, California, USA * |
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* http://www.me.berkeley.edu/~mcmains/pubs/DAC05OffsetPolygon.pdf * |
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* * |
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*******************************************************************************/ |
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/******************************************************************************* |
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* * |
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* This is a translation of the Delphi Clipper library and the naming style * |
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* used has retained a Delphi flavour. * |
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* * |
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*******************************************************************************/ |
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|
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// Changes introduced. (Venkify). |
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// * Ability to query Normals along the generated path wrt pivot. |
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// * Additional information that is helpful if the path needs Tessellation. |
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// * Above functionality has been tested against single path Offset. |
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// * Removed unused/unsupported code. |
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|
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// use_lines: Enables open path clipping. Adds a very minor cost to performance. |
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#define use_lines |
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|
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using System; |
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using System.Collections.Generic; |
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//using System.Text; //for Int128.AsString() & StringBuilder |
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//using System.IO; //debugging with streamReader & StreamWriter |
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//using System.Windows.Forms; //debugging to clipboard |
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|
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namespace UnityEngine.Rendering.Universal |
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{ |
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using ClipInt = Int64; |
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using Path = List<IntPoint>; |
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using Paths = List<List<IntPoint>>; |
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|
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internal struct DoublePoint |
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{ |
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public double X; |
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public double Y; |
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public DoublePoint(double x = 0, double y = 0) |
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{ |
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this.X = x; this.Y = y; |
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} |
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|
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public DoublePoint(DoublePoint dp) |
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{ |
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this.X = dp.X; this.Y = dp.Y; |
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} |
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|
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public DoublePoint(IntPoint ip) |
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{ |
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this.X = ip.X; this.Y = ip.Y; |
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} |
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}; |
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//------------------------------------------------------------------------------ |
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// PolyTree & PolyNode classes |
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//------------------------------------------------------------------------------ |
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internal class PolyTree : PolyNode |
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{ |
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internal List<PolyNode> m_AllPolys = new List<PolyNode>(); |
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|
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//The GC probably handles this cleanup more efficiently ... |
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//~PolyTree(){Clear();} |
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|
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public void Clear() |
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{ |
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for (int i = 0; i < m_AllPolys.Count; i++) |
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m_AllPolys[i] = null; |
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m_AllPolys.Clear(); |
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m_Childs.Clear(); |
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} |
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|
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public PolyNode GetFirst() |
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{ |
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if (m_Childs.Count > 0) |
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return m_Childs[0]; |
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else |
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return null; |
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} |
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|
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public int Total |
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{ |
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get |
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{ |
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int result = m_AllPolys.Count; |
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//with negative offsets, ignore the hidden outer polygon ... |
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if (result > 0 && m_Childs[0] != m_AllPolys[0]) result--; |
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return result; |
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} |
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} |
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} |
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internal class PolyNode |
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{ |
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internal PolyNode m_Parent; |
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internal Path m_polygon = new Path(); |
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internal int m_Index; |
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internal JoinType m_jointype; |
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internal EndType m_endtype; |
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internal List<PolyNode> m_Childs = new List<PolyNode>(); |
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|
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private bool IsHoleNode() |
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{ |
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bool result = true; |
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PolyNode node = m_Parent; |
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while (node != null) |
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{ |
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result = !result; |
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node = node.m_Parent; |
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} |
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return result; |
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} |
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|
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public int ChildCount |
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{ |
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get { return m_Childs.Count; } |
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} |
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|
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public Path Contour |
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{ |
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get { return m_polygon; } |
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} |
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internal void AddChild(PolyNode Child) |
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{ |
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int cnt = m_Childs.Count; |
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m_Childs.Add(Child); |
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Child.m_Parent = this; |
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Child.m_Index = cnt; |
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} |
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|
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public PolyNode GetNext() |
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{ |
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if (m_Childs.Count > 0) |
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return m_Childs[0]; |
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else |
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return GetNextSiblingUp(); |
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} |
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|
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internal PolyNode GetNextSiblingUp() |
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{ |
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if (m_Parent == null) |
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return null; |
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else if (m_Index == m_Parent.m_Childs.Count - 1) |
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return m_Parent.GetNextSiblingUp(); |
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else |
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return m_Parent.m_Childs[m_Index + 1]; |
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} |
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|
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public List<PolyNode> Childs |
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{ |
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get { return m_Childs; } |
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} |
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|
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public PolyNode Parent |
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{ |
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get { return m_Parent; } |
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} |
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public bool IsHole |
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{ |
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get { return IsHoleNode(); } |
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} |
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public bool IsOpen { get; set; } |
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} |
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//------------------------------------------------------------------------------ |
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// Int128 struct (enables safe math on signed 64bit integers) |
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// eg Int128 val1((Int64)9223372036854775807); //ie 2^63 -1 |
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// Int128 val2((Int64)9223372036854775807); |
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// Int128 val3 = val1 * val2; |
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// val3.ToString => "85070591730234615847396907784232501249" (8.5e+37) |
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//------------------------------------------------------------------------------ |
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|
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internal struct Int128 |
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{ |
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private Int64 hi; |
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private UInt64 lo; |
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|
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public Int128(Int64 _lo) |
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{ |
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lo = (UInt64)_lo; |
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if (_lo < 0) hi = -1; |
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else hi = 0; |
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} |
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|
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public Int128(Int64 _hi, UInt64 _lo) |
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{ |
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lo = _lo; |
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hi = _hi; |
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} |
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|
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public Int128(Int128 val) |
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{ |
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hi = val.hi; |
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lo = val.lo; |
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} |
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|
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public bool IsNegative() |
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{ |
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return hi < 0; |
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} |
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|
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public static bool operator ==(Int128 val1, Int128 val2) |
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{ |
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if ((object)val1 == (object)val2) return true; |
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else if ((object)val1 == null || (object)val2 == null) return false; |
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return (val1.hi == val2.hi && val1.lo == val2.lo); |
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} |
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|
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public static bool operator !=(Int128 val1, Int128 val2) |
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{ |
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return !(val1 == val2); |
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} |
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|
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public override bool Equals(System.Object obj) |
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{ |
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if (obj == null || !(obj is Int128)) |
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return false; |
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Int128 i128 = (Int128)obj; |
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return (i128.hi == hi && i128.lo == lo); |
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} |
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|
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public override int GetHashCode() |
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{ |
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return hi.GetHashCode() ^ lo.GetHashCode(); |
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} |
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|
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public static bool operator >(Int128 val1, Int128 val2) |
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{ |
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if (val1.hi != val2.hi) |
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return val1.hi > val2.hi; |
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else |
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return val1.lo > val2.lo; |
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} |
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|
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public static bool operator <(Int128 val1, Int128 val2) |
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{ |
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if (val1.hi != val2.hi) |
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return val1.hi < val2.hi; |
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else |
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return val1.lo < val2.lo; |
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} |
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|
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public static Int128 operator +(Int128 lhs, Int128 rhs) |
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{ |
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lhs.hi += rhs.hi; |
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lhs.lo += rhs.lo; |
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if (lhs.lo < rhs.lo) lhs.hi++; |
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return lhs; |
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} |
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|
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public static Int128 operator -(Int128 lhs, Int128 rhs) |
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{ |
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return lhs + -rhs; |
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} |
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|
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public static Int128 operator -(Int128 val) |
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{ |
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if (val.lo == 0) |
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return new Int128(-val.hi, 0); |
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else |
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return new Int128(~val.hi, ~val.lo + 1); |
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} |
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|
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public static explicit operator double(Int128 val) |
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{ |
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const double shift64 = 18446744073709551616.0; //2^64 |
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if (val.hi < 0) |
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{ |
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if (val.lo == 0) |
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return (double)val.hi * shift64; |
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else |
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return -(double)(~val.lo + ~val.hi * shift64); |
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} |
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else |
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return (double)(val.lo + val.hi * shift64); |
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} |
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|
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//nb: Constructing two new Int128 objects every time we want to multiply longs |
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//is slow. So, although calling the Int128Mul method doesn't look as clean, the |
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//code runs significantly faster than if we'd used the * operator. |
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|
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public static Int128 Int128Mul(Int64 lhs, Int64 rhs) |
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{ |
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bool negate = (lhs < 0) != (rhs < 0); |
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if (lhs < 0) lhs = -lhs; |
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if (rhs < 0) rhs = -rhs; |
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UInt64 int1Hi = (UInt64)lhs >> 32; |
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UInt64 int1Lo = (UInt64)lhs & 0xFFFFFFFF; |
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UInt64 int2Hi = (UInt64)rhs >> 32; |
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UInt64 int2Lo = (UInt64)rhs & 0xFFFFFFFF; |
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|
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//nb: see comments in clipper.pas |
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UInt64 a = int1Hi * int2Hi; |
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UInt64 b = int1Lo * int2Lo; |
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UInt64 c = int1Hi * int2Lo + int1Lo * int2Hi; |
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|
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UInt64 lo; |
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Int64 hi; |
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hi = (Int64)(a + (c >> 32)); |
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|
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unchecked { lo = (c << 32) + b; } |
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if (lo < b) hi++; |
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Int128 result = new Int128(hi, lo); |
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return negate ? -result : result; |
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} |
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}; |
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|
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//------------------------------------------------------------------------------ |
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//------------------------------------------------------------------------------ |
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|
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internal struct IntPoint |
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{ |
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public ClipInt N; |
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public ClipInt X; |
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public ClipInt Y; |
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public ClipInt D; |
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public double NX; |
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public double NY; |
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|
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public IntPoint(ClipInt X, ClipInt Y) |
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{ |
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this.X = X; this.Y = Y; |
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this.NX = 0; this.NY = 0; |
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this.N = -1; this.D = 0; |
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} |
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|
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public IntPoint(double x, double y) |
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{ |
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this.X = (ClipInt)x; this.Y = (ClipInt)y; |
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this.NX = 0; this.NY = 0; |
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this.N = -1; this.D = 0; |
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} |
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|
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public IntPoint(IntPoint pt) |
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{ |
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this.X = pt.X; this.Y = pt.Y; |
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this.NX = pt.NX; this.NY = pt.NY; |
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this.N = pt.N; this.D = pt.D; |
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} |
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|
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public static bool operator ==(IntPoint a, IntPoint b) |
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{ |
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return a.X == b.X && a.Y == b.Y; |
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} |
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|
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public static bool operator !=(IntPoint a, IntPoint b) |
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{ |
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return a.X != b.X || a.Y != b.Y; |
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} |
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|
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public override bool Equals(object obj) |
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{ |
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if (obj == null) return false; |
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if (obj is IntPoint) |
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{ |
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IntPoint a = (IntPoint)obj; |
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return (X == a.X) && (Y == a.Y); |
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} |
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else return false; |
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} |
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|
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public override int GetHashCode() |
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{ |
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//simply prevents a compiler warning |
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return base.GetHashCode(); |
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} |
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}// end struct IntPoint |
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|
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internal struct IntRect |
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{ |
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public ClipInt left; |
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public ClipInt top; |
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public ClipInt right; |
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public ClipInt bottom; |
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|
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public IntRect(ClipInt l, ClipInt t, ClipInt r, ClipInt b) |
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{ |
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this.left = l; this.top = t; |
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this.right = r; this.bottom = b; |
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} |
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|
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public IntRect(IntRect ir) |
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{ |
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this.left = ir.left; this.top = ir.top; |
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this.right = ir.right; this.bottom = ir.bottom; |
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} |
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} |
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|
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public enum ClipType { ctIntersection, ctUnion, ctDifference, ctXor }; |
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public enum PolyType { ptSubject, ptClip }; |
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|
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//By far the most widely used winding rules for polygon filling are |
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//EvenOdd & NonZero (GDI, GDI+, XLib, OpenGL, Cairo, AGG, Quartz, SVG, Gr32) |
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//Others rules include Positive, Negative and ABS_GTR_EQ_TWO (only in OpenGL) |
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//see http://glprogramming.com/red/chapter11.html |
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public enum PolyFillType { pftEvenOdd, pftNonZero, pftPositive, pftNegative }; |
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public enum JoinType { jtRound }; |
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public enum EndType { etClosedPolygon, etClosedLine }; |
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|
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internal enum EdgeSide { esLeft, esRight }; |
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internal enum Direction { dRightToLeft, dLeftToRight }; |
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|
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internal class TEdge |
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{ |
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internal IntPoint Bot; |
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internal IntPoint Curr; //current (updated for every new scanbeam) |
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internal IntPoint Top; |
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internal IntPoint Delta; |
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internal double Dx; |
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internal PolyType PolyTyp; |
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internal EdgeSide Side; //side only refers to current side of solution poly |
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internal int WindDelta; //1 or -1 depending on winding direction |
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internal int WindCnt; |
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internal int WindCnt2; //winding count of the opposite polytype |
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internal int OutIdx; |
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internal TEdge Next; |
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internal TEdge Prev; |
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internal TEdge NextInLML; |
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internal TEdge NextInAEL; |
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internal TEdge PrevInAEL; |
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internal TEdge NextInSEL; |
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internal TEdge PrevInSEL; |
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}; |
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|
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internal class IntersectNode |
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{ |
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internal TEdge Edge1; |
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internal TEdge Edge2; |
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internal IntPoint Pt; |
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}; |
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|
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internal class MyIntersectNodeSort : IComparer<IntersectNode> |
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{ |
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public int Compare(IntersectNode node1, IntersectNode node2) |
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{ |
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ClipInt i = node2.Pt.Y - node1.Pt.Y; |
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if (i > 0) return 1; |
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else if (i < 0) return -1; |
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else return 0; |
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} |
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} |
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|
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internal class LocalMinima |
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{ |
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internal ClipInt Y; |
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internal TEdge LeftBound; |
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internal TEdge RightBound; |
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internal LocalMinima Next; |
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}; |
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|
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internal class Scanbeam |
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{ |
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internal ClipInt Y; |
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internal Scanbeam Next; |
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}; |
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|
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internal class Maxima |
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{ |
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internal ClipInt X; |
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internal Maxima Next; |
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internal Maxima Prev; |
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}; |
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|
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//OutRec: contains a path in the clipping solution. Edges in the AEL will |
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//carry a pointer to an OutRec when they are part of the clipping solution. |
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internal class OutRec |
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{ |
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internal int Idx; |
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internal bool IsHole; |
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internal bool IsOpen; |
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internal OutRec FirstLeft; //see comments in clipper.pas |
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internal OutPt Pts; |
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internal OutPt BottomPt; |
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internal PolyNode PolyNode; |
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}; |
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|
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internal class OutPt |
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{ |
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internal int Idx; |
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internal IntPoint Pt; |
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internal OutPt Next; |
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internal OutPt Prev; |
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}; |
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|
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internal class Join |
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{ |
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internal OutPt OutPt1; |
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internal OutPt OutPt2; |
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internal IntPoint OffPt; |
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}; |
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|
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internal class ClipperBase |
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{ |
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internal const double horizontal = -3.4E+38; |
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internal const int Skip = -2; |
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internal const int Unassigned = -1; |
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internal const double tolerance = 1.0E-20; |
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internal static bool near_zero(double val) { return (val > -tolerance) && (val < tolerance); } |
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|
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public const ClipInt loRange = 0x3FFFFFFF; |
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public const ClipInt hiRange = 0x3FFFFFFFFFFFFFFFL; |
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|
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internal LocalMinima m_MinimaList; |
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internal LocalMinima m_CurrentLM; |
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internal List<List<TEdge>> m_edges = new List<List<TEdge>>(); |
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internal Scanbeam m_Scanbeam; |
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internal List<OutRec> m_PolyOuts; |
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internal TEdge m_ActiveEdges; |
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internal bool m_UseFullRange; |
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internal bool m_HasOpenPaths; |
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|
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//------------------------------------------------------------------------------ |
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|
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public bool PreserveCollinear |
|
{ |
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get; |
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set; |
|
} |
|
//------------------------------------------------------------------------------ |
|
|
|
public void Swap(ref ClipInt val1, ref ClipInt val2) |
|
{ |
|
ClipInt tmp = val1; |
|
val1 = val2; |
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val2 = tmp; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
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|
|
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 (ClipInt)(e1.Delta.Y) * (e2.Delta.X) == |
|
(ClipInt)(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 |
|
(ClipInt)(pt1.Y - pt2.Y) * (pt2.X - pt3.X) - (ClipInt)(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 |
|
(ClipInt)(pt1.Y - pt2.Y) * (pt3.X - pt4.X) - (ClipInt)(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(ClipInt Y, out LocalMinima current) |
|
{ |
|
current = m_CurrentLM; |
|
if (m_CurrentLM != null && m_CurrentLM.Y == Y) |
|
{ |
|
m_CurrentLM = m_CurrentLM.Next; |
|
return true; |
|
} |
|
return false; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
private void ReverseHorizontal(TEdge e) |
|
{ |
|
//swap horizontal edges' top and bottom x's so they follow the natural |
|
//progression of the bounds - ie so their xbots will align with the |
|
//adjoining lower edge. [Helpful in the ProcessHorizontal() method.] |
|
Swap(ref e.Top.X, ref e.Bot.X); |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
internal virtual void Reset() |
|
{ |
|
m_CurrentLM = m_MinimaList; |
|
if (m_CurrentLM == null) return; //ie nothing to process |
|
|
|
//reset all edges ... |
|
m_Scanbeam = null; |
|
LocalMinima lm = m_MinimaList; |
|
while (lm != null) |
|
{ |
|
InsertScanbeam(lm.Y); |
|
TEdge e = lm.LeftBound; |
|
if (e != null) |
|
{ |
|
e.Curr = e.Bot; |
|
e.OutIdx = Unassigned; |
|
} |
|
e = lm.RightBound; |
|
if (e != null) |
|
{ |
|
e.Curr = e.Bot; |
|
e.OutIdx = Unassigned; |
|
} |
|
lm = lm.Next; |
|
} |
|
m_ActiveEdges = null; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
public static IntRect GetBounds(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(ClipInt 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 ClipInt 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 |
|
|
|
internal class Clipper : ClipperBase |
|
{ |
|
//InitOptions that can be passed to the constructor ... |
|
public const int ioReverseSolution = 1; |
|
public const int ioStrictlySimple = 2; |
|
public const int ioPreserveCollinear = 4; |
|
|
|
private ClipType m_ClipType; |
|
private Maxima m_Maxima; |
|
private TEdge m_SortedEdges; |
|
private 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; |
|
|
|
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; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
private void InsertMaxima(ClipInt 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 int LastIndex |
|
{ |
|
get; |
|
set; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
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; |
|
|
|
ClipInt 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); |
|
} |
|
|
|
private void InsertLocalMinimaIntoAEL(ClipInt 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) |
|
{ |
|
ClipInt xPrev = TopX(prevE, pt.Y); |
|
ClipInt 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(ClipInt seg1a, ClipInt seg1b, ClipInt seg2a, ClipInt 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_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 ... |
|
ClipInt 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 ClipInt Left, out ClipInt 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; |
|
ClipInt 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 |
|
{ |
|
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(ClipInt 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(ClipInt 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 ClipInt Round(double value) |
|
{ |
|
return value < 0 ? (ClipInt)(value - 0.5) : (ClipInt)(value + 0.5); |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
private static ClipInt TopX(TEdge edge, ClipInt 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(); |
|
long pivotPoint = -1; |
|
bool isClamp = (edge2.Curr.N > 0 && edge2.Curr.N < LastIndex) && (edge1.Curr.N > 0 && edge1.Curr.N < LastIndex); |
|
if (edge1.Curr.N > edge2.Curr.N) |
|
{ |
|
if (edge2.Curr.N != -1) |
|
{ |
|
if (isClamp) |
|
{ |
|
pivotPoint = (edge1.Curr.N > 0) ? edge1.Curr.N - 1 : 0; |
|
} |
|
} |
|
else |
|
{ |
|
pivotPoint = edge1.Curr.N; |
|
} |
|
} |
|
else |
|
{ |
|
if (edge1.Curr.N != -1) |
|
{ |
|
if (isClamp) |
|
{ |
|
pivotPoint = edge2.Curr.N; |
|
} |
|
} |
|
else |
|
{ |
|
pivotPoint = (edge2.Curr.N > 0) ? edge2.Curr.N - 1 : 0; |
|
} |
|
} |
|
ip.D = 2; ip.N = isClamp ? pivotPoint : -1; |
|
|
|
//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; |
|
} |
|
|
|
double b1, b2; |
|
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(ClipInt topY) |
|
{ |
|
TEdge e = m_ActiveEdges; |
|
while (e != null) |
|
{ |
|
//1. process maxima, treating them as if they're 'bent' horizontal edges, |
|
// but exclude maxima with horizontal edges. nb: e can't be a horizontal. |
|
bool IsMaximaEdge = IsMaxima(e, topY); |
|
|
|
if (IsMaximaEdge) |
|
{ |
|
TEdge eMaxPair = GetMaximaPairEx(e); |
|
IsMaximaEdge = (eMaxPair == null || !IsHorizontal(eMaxPair)); |
|
} |
|
|
|
if (IsMaximaEdge) |
|
{ |
|
if (StrictlySimple) InsertMaxima(e.Top.X); |
|
TEdge ePrev = e.PrevInAEL; |
|
DoMaxima(e); |
|
if (ePrev == null) e = m_ActiveEdges; |
|
else e = ePrev.NextInAEL; |
|
} |
|
else |
|
{ |
|
//2. promote horizontal edges, otherwise update Curr.X and Curr.Y ... |
|
if (IsIntermediate(e, topY) && IsHorizontal(e.NextInLML)) |
|
{ |
|
UpdateEdgeIntoAEL(ref e); |
|
if (e.OutIdx >= 0) |
|
AddOutPt(e, e.Bot); |
|
AddEdgeToSEL(e); |
|
} |
|
else |
|
{ |
|
e.Curr.X = TopX(e, topY); |
|
e.Curr.Y = topY; |
|
} |
|
//When StrictlySimple and 'e' is being touched by another edge, then |
|
//make sure both edges have a vertex here ... |
|
if (StrictlySimple) |
|
{ |
|
TEdge ePrev = e.PrevInAEL; |
|
if ((e.OutIdx >= 0) && (e.WindDelta != 0) && ePrev != null && |
|
(ePrev.OutIdx >= 0) && (ePrev.Curr.X == e.Curr.X) && |
|
(ePrev.WindDelta != 0)) |
|
{ |
|
IntPoint ip = new IntPoint(e.Curr); |
|
OutPt op = AddOutPt(ePrev, ip); |
|
OutPt op2 = AddOutPt(e, ip); |
|
AddJoin(op, op2, ip); //StrictlySimple (type-3) join |
|
} |
|
} |
|
|
|
e = e.NextInAEL; |
|
} |
|
} |
|
|
|
//3. Process horizontals at the Top of the scanbeam ... |
|
ProcessHorizontals(); |
|
m_Maxima = null; |
|
|
|
//4. Promote intermediate vertices ... |
|
e = m_ActiveEdges; |
|
while (e != null) |
|
{ |
|
if (IsIntermediate(e, topY)) |
|
{ |
|
OutPt op = null; |
|
if (e.OutIdx >= 0) |
|
op = AddOutPt(e, e.Top); |
|
UpdateEdgeIntoAEL(ref e); |
|
|
|
//if output polygons share an edge, they'll need joining later ... |
|
TEdge ePrev = e.PrevInAEL; |
|
TEdge eNext = e.NextInAEL; |
|
if (ePrev != null && ePrev.Curr.X == e.Bot.X && |
|
ePrev.Curr.Y == e.Bot.Y && op != null && |
|
ePrev.OutIdx >= 0 && ePrev.Curr.Y > ePrev.Top.Y && |
|
SlopesEqual(e.Curr, e.Top, ePrev.Curr, ePrev.Top, m_UseFullRange) && |
|
(e.WindDelta != 0) && (ePrev.WindDelta != 0)) |
|
{ |
|
OutPt op2 = AddOutPt(ePrev, e.Bot); |
|
AddJoin(op, op2, e.Top); |
|
} |
|
else if (eNext != null && eNext.Curr.X == e.Bot.X && |
|
eNext.Curr.Y == e.Bot.Y && op != null && |
|
eNext.OutIdx >= 0 && eNext.Curr.Y > eNext.Top.Y && |
|
SlopesEqual(e.Curr, e.Top, eNext.Curr, eNext.Top, m_UseFullRange) && |
|
(e.WindDelta != 0) && (eNext.WindDelta != 0)) |
|
{ |
|
OutPt op2 = AddOutPt(eNext, e.Bot); |
|
AddJoin(op, op2, e.Top); |
|
} |
|
} |
|
e = e.NextInAEL; |
|
} |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
private void DoMaxima(TEdge e) |
|
{ |
|
TEdge eMaxPair = GetMaximaPairEx(e); |
|
if (eMaxPair == null) |
|
{ |
|
if (e.OutIdx >= 0) |
|
AddOutPt(e, e.Top); |
|
DeleteFromAEL(e); |
|
return; |
|
} |
|
|
|
TEdge eNext = e.NextInAEL; |
|
while (eNext != null && eNext != eMaxPair) |
|
{ |
|
IntersectEdges(e, eNext, e.Top); |
|
SwapPositionsInAEL(e, eNext); |
|
eNext = e.NextInAEL; |
|
} |
|
|
|
if (e.OutIdx == Unassigned && eMaxPair.OutIdx == Unassigned) |
|
{ |
|
DeleteFromAEL(e); |
|
DeleteFromAEL(eMaxPair); |
|
} |
|
else if (e.OutIdx >= 0 && eMaxPair.OutIdx >= 0) |
|
{ |
|
if (e.OutIdx >= 0) AddLocalMaxPoly(e, eMaxPair, e.Top); |
|
DeleteFromAEL(e); |
|
DeleteFromAEL(eMaxPair); |
|
} |
|
#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(ClipInt a1, ClipInt a2, ClipInt b1, ClipInt b2, out ClipInt Left, out ClipInt 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' |
|
|
|
ClipInt 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; |
|
ClipInt ptx = pt.X, pty = pt.Y; |
|
ClipInt poly0x = op.Pt.X, poly0y = op.Pt.Y; |
|
do |
|
{ |
|
op = op.Next; |
|
ClipInt 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 |
|
|
|
internal 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_StepsPerRad; |
|
|
|
private IntPoint m_lowest; |
|
private PolyNode m_polyNodes = new PolyNode(); |
|
|
|
public double ArcTolerance { get; set; } |
|
|
|
private const double two_pi = Math.PI * 2; |
|
private const double def_arc_tolerance = 0.25; |
|
|
|
public ClipperOffset(double arcTolerance = def_arc_tolerance) |
|
{ |
|
ArcTolerance = arcTolerance; |
|
m_lowest.X = -1; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
public void Clear() |
|
{ |
|
m_polyNodes.Childs.Clear(); |
|
m_lowest.X = -1; |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
internal static ClipInt Round(double value) |
|
{ |
|
return value < 0 ? (ClipInt)(value - 0.5) : (ClipInt)(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; |
|
} |
|
|
|
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); |
|
|
|
{ |
|
int j = len - 1; |
|
k = len - 2; |
|
m_sinA = 0; |
|
m_normals[j] = new DoublePoint(-m_normals[j].X, -m_normals[j].Y); |
|
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); |
|
|
|
{ |
|
k = 1; |
|
m_sinA = 0; |
|
DoRound(0, 1); |
|
} |
|
m_destPolys.Add(m_destPoly); |
|
} |
|
} |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
public void Execute(ref Paths solution, double delta, int inputSize) |
|
{ |
|
solution.Clear(); |
|
FixOrientations(); |
|
DoOffset(delta); |
|
//now clean up 'corners' ... |
|
Clipper clpr = new Clipper(); |
|
clpr.AddPaths(m_destPolys, PolyType.ptSubject, true); |
|
clpr.LastIndex = inputSize - 1; |
|
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 |
|
{ |
|
var item = new IntPoint(Round(m_srcPoly[j].X + m_normals[k].X * m_delta), |
|
Round(m_srcPoly[j].Y + m_normals[k].Y * m_delta)); |
|
item.NX = m_normals[k].X; item.NY = m_normals[k].Y; item.N = j; item.D = 1; |
|
m_destPoly.Add(item); |
|
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) |
|
{ |
|
var pt = new IntPoint(Round(m_srcPoly[j].X + m_normals[k].X * m_delta), |
|
Round(m_srcPoly[j].Y + m_normals[k].Y * m_delta)); |
|
pt.NX = m_normals[k].X; pt.NY = m_normals[k].Y; |
|
m_destPoly.Add(pt); |
|
pt = m_srcPoly[j]; |
|
pt.NX = m_normals[k].X; pt.NY = m_normals[k].Y; pt.N = j; pt.D = 1; |
|
m_destPoly.Add(pt); |
|
pt = new IntPoint(Round(m_srcPoly[j].X + m_normals[j].X * m_delta), |
|
Round(m_srcPoly[j].Y + m_normals[j].Y * m_delta)); |
|
pt.NX = m_normals[j].X; pt.NY = m_normals[j].Y; pt.N = j; pt.D = 1; |
|
m_destPoly.Add(pt); |
|
} |
|
else |
|
switch (jointype) |
|
{ |
|
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); |
|
var pt = 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))); |
|
pt.NX = m_normals[k].X - m_normals[k].Y * dx; pt.NY = m_normals[k].Y + m_normals[k].X * dx; |
|
m_destPoly.Add(pt); |
|
pt = 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))); |
|
pt.NX = m_normals[k].X + m_normals[k].Y * dx; pt.NY = m_normals[k].Y - m_normals[k].X * dx; |
|
m_destPoly.Add(pt); |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
internal void DoMiter(int j, int k, double r) |
|
{ |
|
double q = m_delta / r; |
|
var pt = 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)); |
|
pt.NX = (m_normals[k].X + m_normals[j].X) * q; pt.NY = (m_normals[k].Y + m_normals[j].Y) * q; |
|
m_destPoly.Add(pt); |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
|
|
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) |
|
{ |
|
var pt = new IntPoint( |
|
Round(m_srcPoly[j].X + X * m_delta), |
|
Round(m_srcPoly[j].Y + Y * m_delta)); |
|
pt.NX = X; pt.NY = Y; pt.N = j; pt.D = 1; |
|
m_destPoly.Add(pt); |
|
X2 = X; |
|
X = X * m_cos - m_sin * Y; |
|
Y = X2 * m_sin + Y * m_cos; |
|
} |
|
|
|
var pt1 = new IntPoint( |
|
Round(m_srcPoly[j].X + m_normals[j].X * m_delta), |
|
Round(m_srcPoly[j].Y + m_normals[j].Y * m_delta)); |
|
pt1.NX = m_normals[j].X; pt1.NY = m_normals[j].Y; pt1.N = j; pt1.D = 1; |
|
m_destPoly.Add(pt1); |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
} |
|
|
|
class ClipperException : Exception |
|
{ |
|
public ClipperException(string description) : base(description) { } |
|
} |
|
//------------------------------------------------------------------------------ |
|
} //end ClipperLib namespace
|
|
|