5970 lines
156 KiB
C++
5970 lines
156 KiB
C++
/*******************************************************************************
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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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#include "clipper.hpp"
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#include <cmath>
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#include <vector>
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#include <algorithm>
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#include <stdexcept>
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#include <cstring>
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#include <cstdlib>
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#include <ostream>
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#include <functional>
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namespace ClipperLib {
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static double const pi = 3.141592653589793238;
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static double const two_pi = pi * 2;
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static double const def_arc_tolerance = 0.25;
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enum Direction
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{
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dRightToLeft, dLeftToRight
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};
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static int const Unassigned = -1; // edge not currently 'owning' a solution
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static int const Skip = -2; // edge that would otherwise close a path
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#define HORIZONTAL (-1.0E+40)
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#define TOLERANCE (1.0e-20)
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#define NEAR_ZERO( val ) ( ( (val) > -TOLERANCE ) && ( (val) < TOLERANCE ) )
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struct TEdge
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{
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IntPoint Bot;
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IntPoint Curr; // current (updated for every new scanbeam)
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IntPoint Top;
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double Dx;
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PolyType PolyTyp;
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EdgeSide Side; // side only refers to current side of solution poly
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int WindDelta; // 1 or -1 depending on winding direction
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int WindCnt;
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int WindCnt2; // winding count of the opposite polytype
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int OutIdx;
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TEdge* Next;
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TEdge* Prev;
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TEdge* NextInLML;
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TEdge* NextInAEL;
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TEdge* PrevInAEL;
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TEdge* NextInSEL;
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TEdge* PrevInSEL;
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};
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struct IntersectNode
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{
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TEdge* Edge1;
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TEdge* Edge2;
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IntPoint Pt;
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};
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struct LocalMinimum
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{
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cInt Y;
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TEdge* LeftBound;
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TEdge* RightBound;
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};
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struct OutPt;
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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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struct OutRec
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{
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int Idx;
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bool IsHole;
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bool IsOpen;
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OutRec* FirstLeft; // see comments in clipper.pas
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PolyNode* PolyNd;
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OutPt* Pts;
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OutPt* BottomPt;
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};
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struct OutPt
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{
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int Idx;
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IntPoint Pt;
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OutPt* Next;
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OutPt* Prev;
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};
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struct Join
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{
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OutPt* OutPt1;
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OutPt* OutPt2;
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IntPoint OffPt;
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};
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struct LocMinSorter
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{
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inline bool operator()( const LocalMinimum& locMin1, const LocalMinimum& locMin2 )
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{
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return locMin2.Y < locMin1.Y;
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}
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};
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// ------------------------------------------------------------------------------
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// ------------------------------------------------------------------------------
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inline cInt Round( double val )
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{
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if( (val < 0) )
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return static_cast<cInt>(val - 0.5);
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else
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return static_cast<cInt>(val + 0.5);
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}
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// ------------------------------------------------------------------------------
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inline cInt Abs( cInt val )
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{
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return val < 0 ? -val : val;
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}
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// ------------------------------------------------------------------------------
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// PolyTree methods ...
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// ------------------------------------------------------------------------------
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void PolyTree::Clear()
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{
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for( PolyNodes::size_type i = 0; i < AllNodes.size(); ++i )
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delete AllNodes[i];
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AllNodes.resize( 0 );
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Childs.resize( 0 );
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}
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// ------------------------------------------------------------------------------
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PolyNode* PolyTree::GetFirst() const
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{
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if( !Childs.empty() )
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return Childs[0];
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else
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return 0;
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}
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// ------------------------------------------------------------------------------
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int PolyTree::Total() const
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{
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int result = (int) AllNodes.size();
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// with negative offsets, ignore the hidden outer polygon ...
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if( result > 0 && Childs[0] != AllNodes[0] )
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result--;
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return result;
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}
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// ------------------------------------------------------------------------------
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// PolyNode methods ...
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// ------------------------------------------------------------------------------
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PolyNode::PolyNode() : Parent( 0 ), Index( 0 ), m_IsOpen( false )
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{
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}
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// ------------------------------------------------------------------------------
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int PolyNode::ChildCount() const
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{
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return (int) Childs.size();
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}
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// ------------------------------------------------------------------------------
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void PolyNode::AddChild( PolyNode& child )
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{
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unsigned cnt = (unsigned) Childs.size();
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Childs.push_back( &child );
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child.Parent = this;
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child.Index = cnt;
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}
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// ------------------------------------------------------------------------------
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PolyNode* PolyNode::GetNext() const
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{
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if( !Childs.empty() )
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return 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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PolyNode* PolyNode::GetNextSiblingUp() const
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{
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if( !Parent ) // protects against PolyTree.GetNextSiblingUp()
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return 0;
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else if( Index == Parent->Childs.size() - 1 )
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return Parent->GetNextSiblingUp();
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else
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return Parent->Childs[Index + 1];
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}
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// ------------------------------------------------------------------------------
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bool PolyNode::IsHole() const
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{
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bool result = true;
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PolyNode* node = Parent;
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while( node )
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{
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result = !result;
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node = node->Parent;
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}
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return result;
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}
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// ------------------------------------------------------------------------------
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bool PolyNode::IsOpen() const
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{
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return m_IsOpen;
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}
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// ------------------------------------------------------------------------------
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#ifndef use_int32
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// ------------------------------------------------------------------------------
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// Int128 class (enables safe math on signed 64bit integers)
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// eg Int128 val1((long64)9223372036854775807); //ie 2^63 -1
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// Int128 val2((long64)9223372036854775807);
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// Int128 val3 = val1 * val2;
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// val3.AsString => "85070591730234615847396907784232501249" (8.5e+37)
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// ------------------------------------------------------------------------------
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class Int128
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{
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public:
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ulong64 lo;
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long64 hi;
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Int128( long64 _lo = 0 )
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{
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lo = (ulong64) _lo;
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if( _lo < 0 ) hi = -1; else hi = 0;
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}
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Int128( const Int128& val ) : lo( val.lo ), hi( val.hi ) {}
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Int128( const long64& _hi, const ulong64& _lo ) : lo( _lo ), hi( _hi ) {}
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Int128& operator =( const long64& val )
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{
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lo = (ulong64) val;
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if( val < 0 ) hi = -1; else hi = 0;
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return *this;
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}
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bool operator ==( const Int128& val ) const
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{ return hi == val.hi && lo == val.lo; }
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bool operator !=( const Int128& val ) const
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{ return !(*this == val); }
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bool operator >( const Int128& val ) const
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{
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if( hi != val.hi )
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return hi > val.hi;
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else
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return lo > val.lo;
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}
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bool operator <( const Int128& val ) const
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{
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if( hi != val.hi )
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return hi < val.hi;
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else
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return lo < val.lo;
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}
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bool operator >=( const Int128& val ) const
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{ return !(*this < val); }
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bool operator <=( const Int128& val ) const
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{ return !(*this > val); }
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Int128& operator +=( const Int128& rhs )
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{
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hi += rhs.hi;
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lo += rhs.lo;
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if( lo < rhs.lo ) hi++;
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return *this;
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}
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Int128 operator +( const Int128& rhs ) const
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{
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Int128 result( *this );
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result += rhs;
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return result;
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}
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Int128& operator -=( const Int128& rhs )
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{
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*this += -rhs;
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return *this;
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}
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Int128 operator -( const Int128& rhs ) const
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{
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Int128 result( *this );
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result -= rhs;
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return result;
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}
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Int128 operator-() const // unary negation
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{
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if( lo == 0 )
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return Int128( -hi, 0 );
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else
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return Int128( ~hi, ~lo + 1 );
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}
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operator double() const
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{
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const double shift64 = 18446744073709551616.0; // 2^64
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if( hi < 0 )
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{
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if( lo == 0 ) return (double) hi * shift64;
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else return -(double) (~lo + ~hi * shift64);
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}
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else
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return (double) (lo + hi * shift64);
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}
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};
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// ------------------------------------------------------------------------------
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Int128 Int128Mul( long64 lhs, long64 rhs )
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{
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bool negate = (lhs < 0) != (rhs < 0);
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if( lhs < 0 )
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lhs = -lhs;
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ulong64 int1Hi = ulong64( lhs ) >> 32;
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ulong64 int1Lo = ulong64( lhs & 0xFFFFFFFF );
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if( rhs < 0 )
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rhs = -rhs;
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ulong64 int2Hi = ulong64( rhs ) >> 32;
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ulong64 int2Lo = ulong64( rhs & 0xFFFFFFFF );
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// nb: see comments in clipper.pas
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ulong64 a = int1Hi * int2Hi;
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ulong64 b = int1Lo * int2Lo;
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ulong64 c = int1Hi * int2Lo + int1Lo * int2Hi;
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Int128 tmp;
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tmp.hi = long64( a + (c >> 32) );
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tmp.lo = long64( c << 32 );
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tmp.lo += long64( b );
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if( tmp.lo < b )
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tmp.hi++;
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if( negate )
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tmp = -tmp;
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return tmp;
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}
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#endif
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// ------------------------------------------------------------------------------
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// Miscellaneous global functions
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// ------------------------------------------------------------------------------
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bool Orientation( const Path& poly )
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{
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return Area( poly ) >= 0;
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}
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// ------------------------------------------------------------------------------
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double Area( const Path& poly )
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{
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int size = (int) poly.size();
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if( size < 3 )
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return 0;
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double a = 0;
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for( int i = 0, j = size - 1; i < size; ++i )
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{
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a += ( (double) poly[j].X + poly[i].X ) * ( (double) poly[j].Y - poly[i].Y );
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j = i;
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}
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return -a * 0.5;
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}
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// ------------------------------------------------------------------------------
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double Area( const OutPt* op )
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{
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const OutPt* startOp = op;
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if( !op )
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return 0;
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double a = 0;
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do {
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a += (double) (op->Prev->Pt.X + op->Pt.X) * (double) (op->Prev->Pt.Y - op->Pt.Y);
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op = op->Next;
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} while( op != startOp );
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return a * 0.5;
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}
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// ------------------------------------------------------------------------------
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double Area( const OutRec& outRec )
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{
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return Area( outRec.Pts );
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}
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// ------------------------------------------------------------------------------
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bool PointIsVertex( const IntPoint& Pt, OutPt* pp )
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{
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OutPt* pp2 = pp;
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do
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{
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if( pp2->Pt == Pt )
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return true;
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pp2 = pp2->Next;
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} while( pp2 != pp );
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return false;
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}
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// ------------------------------------------------------------------------------
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// See "The Point in Polygon Problem for Arbitrary Polygons" by Hormann & Agathos
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// http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.88.5498&rep=rep1&type=pdf
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int PointInPolygon( const IntPoint& pt, const Path& path )
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{
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// returns 0 if false, +1 if true, -1 if pt ON polygon boundary
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int result = 0;
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size_t cnt = path.size();
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if( cnt < 3 )
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return 0;
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IntPoint ip = path[0];
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for( size_t i = 1; i <= cnt; ++i )
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{
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IntPoint ipNext = (i == cnt ? path[0] : path[i]);
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if( ipNext.Y == pt.Y )
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{
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if( (ipNext.X == pt.X) || ( ip.Y == pt.Y
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&& ( (ipNext.X > pt.X) == (ip.X < pt.X) ) ) )
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return -1;
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}
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if( (ip.Y < pt.Y) != (ipNext.Y < pt.Y) )
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{
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if( ip.X >= pt.X )
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{
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if( ipNext.X > pt.X )
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result = 1 - result;
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else
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{
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double d = (double) (ip.X - pt.X) * (ipNext.Y - pt.Y) -
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(double) (ipNext.X - pt.X) * (ip.Y - pt.Y);
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if( !d )
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return -1;
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if( (d > 0) == (ipNext.Y > ip.Y) )
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result = 1 - result;
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}
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}
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else
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{
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if( ipNext.X > pt.X )
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{
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double d = (double) (ip.X - pt.X) * (ipNext.Y - pt.Y) -
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(double) (ipNext.X - pt.X) * (ip.Y - pt.Y);
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if( !d )
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return -1;
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if( (d > 0) == (ipNext.Y > ip.Y) )
|
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result = 1 - result;
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}
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}
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}
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ip = ipNext;
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}
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return result;
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}
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|
|
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// ------------------------------------------------------------------------------
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int PointInPolygon( const IntPoint& pt, OutPt* op )
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{
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// returns 0 if false, +1 if true, -1 if pt ON polygon boundary
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int result = 0;
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OutPt* startOp = op;
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for( ; ; )
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{
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if( op->Next->Pt.Y == pt.Y )
|
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{
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if( (op->Next->Pt.X == pt.X) || ( op->Pt.Y == pt.Y
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&& ( (op->Next->Pt.X > pt.X) ==
|
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(op->Pt.X < pt.X) ) ) )
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return -1;
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}
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|
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if( (op->Pt.Y < pt.Y) != (op->Next->Pt.Y < pt.Y) )
|
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{
|
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if( op->Pt.X >= pt.X )
|
|
{
|
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if( op->Next->Pt.X > pt.X )
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result = 1 - result;
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else
|
|
{
|
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double d = (double) (op->Pt.X - pt.X) * (op->Next->Pt.Y - pt.Y) -
|
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(double) (op->Next->Pt.X - pt.X) * (op->Pt.Y - pt.Y);
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|
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if( !d )
|
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return -1;
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|
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if( (d > 0) == (op->Next->Pt.Y > op->Pt.Y) )
|
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result = 1 - result;
|
|
}
|
|
}
|
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else
|
|
{
|
|
if( op->Next->Pt.X > pt.X )
|
|
{
|
|
double d = (double) (op->Pt.X - pt.X) * (op->Next->Pt.Y - pt.Y) -
|
|
(double) (op->Next->Pt.X - pt.X) * (op->Pt.Y - pt.Y);
|
|
|
|
if( !d )
|
|
return -1;
|
|
|
|
if( (d > 0) == (op->Next->Pt.Y > op->Pt.Y) )
|
|
result = 1 - result;
|
|
}
|
|
}
|
|
}
|
|
|
|
op = op->Next;
|
|
|
|
if( startOp == op )
|
|
break;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Poly2ContainsPoly1( OutPt* OutPt1, OutPt* OutPt2 )
|
|
{
|
|
OutPt* op = OutPt1;
|
|
|
|
do
|
|
{
|
|
// nb: PointInPolygon returns 0 if false, +1 if true, -1 if pt on polygon
|
|
int res = PointInPolygon( op->Pt, OutPt2 );
|
|
|
|
if( res >= 0 )
|
|
return res > 0;
|
|
|
|
op = op->Next;
|
|
} while( op != OutPt1 );
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------
|
|
|
|
bool SlopesEqual( const TEdge& e1, const TEdge& e2, bool UseFullInt64Range )
|
|
{
|
|
#ifndef use_int32
|
|
|
|
if( UseFullInt64Range )
|
|
return Int128Mul( e1.Top.Y - e1.Bot.Y, e2.Top.X - e2.Bot.X ) ==
|
|
Int128Mul( e1.Top.X - e1.Bot.X, e2.Top.Y - e2.Bot.Y );
|
|
else
|
|
#endif
|
|
return (e1.Top.Y - e1.Bot.Y) * (e2.Top.X - e2.Bot.X) ==
|
|
(e1.Top.X - e1.Bot.X) * (e2.Top.Y - e2.Bot.Y);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool SlopesEqual( const IntPoint pt1, const IntPoint pt2,
|
|
const IntPoint pt3, bool UseFullInt64Range )
|
|
{
|
|
#ifndef use_int32
|
|
|
|
if( UseFullInt64Range )
|
|
return Int128Mul( pt1.Y - pt2.Y,
|
|
pt2.X - pt3.X ) == Int128Mul( pt1.X - pt2.X, pt2.Y - pt3.Y );
|
|
else
|
|
#endif
|
|
return (pt1.Y - pt2.Y) * (pt2.X - pt3.X) == (pt1.X - pt2.X) * (pt2.Y - pt3.Y);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool SlopesEqual( const IntPoint pt1, const IntPoint pt2,
|
|
const IntPoint pt3, const IntPoint pt4, bool UseFullInt64Range )
|
|
{
|
|
#ifndef use_int32
|
|
|
|
if( UseFullInt64Range )
|
|
return Int128Mul( pt1.Y - pt2.Y,
|
|
pt3.X - pt4.X ) == Int128Mul( pt1.X - pt2.X, pt3.Y - pt4.Y );
|
|
else
|
|
#endif
|
|
return (pt1.Y - pt2.Y) * (pt3.X - pt4.X) == (pt1.X - pt2.X) * (pt3.Y - pt4.Y);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline bool IsHorizontal( TEdge& e )
|
|
{
|
|
return e.Dx == HORIZONTAL;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline double GetDx( const IntPoint pt1, const IntPoint pt2 )
|
|
{
|
|
return (pt1.Y == pt2.Y) ?
|
|
HORIZONTAL : (double) (pt2.X - pt1.X) / (pt2.Y - pt1.Y);
|
|
}
|
|
|
|
|
|
// ---------------------------------------------------------------------------
|
|
|
|
inline void SetDx( TEdge& e )
|
|
{
|
|
cInt dy = (e.Top.Y - e.Bot.Y);
|
|
|
|
if( dy == 0 )
|
|
e.Dx = HORIZONTAL;
|
|
else
|
|
e.Dx = (double) (e.Top.X - e.Bot.X) / dy;
|
|
}
|
|
|
|
|
|
// ---------------------------------------------------------------------------
|
|
|
|
inline void SwapSides( TEdge& Edge1, TEdge& Edge2 )
|
|
{
|
|
EdgeSide Side = Edge1.Side;
|
|
|
|
Edge1.Side = Edge2.Side;
|
|
Edge2.Side = Side;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline void SwapPolyIndexes( TEdge& Edge1, TEdge& Edge2 )
|
|
{
|
|
int OutIdx = Edge1.OutIdx;
|
|
|
|
Edge1.OutIdx = Edge2.OutIdx;
|
|
Edge2.OutIdx = OutIdx;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline cInt TopX( TEdge& edge, const cInt currentY )
|
|
{
|
|
return ( currentY == edge.Top.Y ) ?
|
|
edge.Top.X : edge.Bot.X + Round( edge.Dx * (currentY - edge.Bot.Y) );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void IntersectPoint( TEdge& Edge1, TEdge& Edge2, IntPoint& ip )
|
|
{
|
|
#ifdef use_xyz
|
|
ip.Z = 0;
|
|
#endif
|
|
|
|
double b1, b2;
|
|
|
|
if( Edge1.Dx == Edge2.Dx )
|
|
{
|
|
ip.Y = Edge1.Curr.Y;
|
|
ip.X = TopX( Edge1, ip.Y );
|
|
return;
|
|
}
|
|
else if( Edge1.Dx == 0 )
|
|
{
|
|
ip.X = Edge1.Bot.X;
|
|
|
|
if( IsHorizontal( Edge2 ) )
|
|
ip.Y = Edge2.Bot.Y;
|
|
else
|
|
{
|
|
b2 = Edge2.Bot.Y - (Edge2.Bot.X / Edge2.Dx);
|
|
ip.Y = Round( ip.X / Edge2.Dx + b2 );
|
|
}
|
|
}
|
|
else if( Edge2.Dx == 0 )
|
|
{
|
|
ip.X = Edge2.Bot.X;
|
|
|
|
if( IsHorizontal( Edge1 ) )
|
|
ip.Y = Edge1.Bot.Y;
|
|
else
|
|
{
|
|
b1 = Edge1.Bot.Y - (Edge1.Bot.X / Edge1.Dx);
|
|
ip.Y = Round( ip.X / Edge1.Dx + b1 );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
b1 = Edge1.Bot.X - Edge1.Bot.Y * Edge1.Dx;
|
|
b2 = Edge2.Bot.X - Edge2.Bot.Y * Edge2.Dx;
|
|
double q = (b2 - b1) / (Edge1.Dx - Edge2.Dx);
|
|
ip.Y = Round( q );
|
|
|
|
if( std::fabs( Edge1.Dx ) < std::fabs( Edge2.Dx ) )
|
|
ip.X = Round( Edge1.Dx * q + b1 );
|
|
else
|
|
ip.X = Round( Edge2.Dx * q + b2 );
|
|
}
|
|
|
|
if( ip.Y < Edge1.Top.Y || ip.Y < Edge2.Top.Y )
|
|
{
|
|
if( Edge1.Top.Y > Edge2.Top.Y )
|
|
ip.Y = Edge1.Top.Y;
|
|
else
|
|
ip.Y = Edge2.Top.Y;
|
|
|
|
if( std::fabs( Edge1.Dx ) < std::fabs( Edge2.Dx ) )
|
|
ip.X = TopX( Edge1, ip.Y );
|
|
else
|
|
ip.X = TopX( Edge2, ip.Y );
|
|
}
|
|
|
|
// finally, don't allow 'ip' to be BELOW curr.Y (ie bottom of scanbeam) ...
|
|
if( ip.Y > Edge1.Curr.Y )
|
|
{
|
|
ip.Y = Edge1.Curr.Y;
|
|
|
|
// use the more vertical edge to derive X ...
|
|
if( std::fabs( Edge1.Dx ) > std::fabs( Edge2.Dx ) )
|
|
ip.X = TopX( Edge2, ip.Y );
|
|
else
|
|
ip.X = TopX( Edge1, ip.Y );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ReversePolyPtLinks( OutPt* pp )
|
|
{
|
|
if( !pp )
|
|
return;
|
|
|
|
OutPt* pp1, * pp2;
|
|
pp1 = pp;
|
|
|
|
do {
|
|
pp2 = pp1->Next;
|
|
pp1->Next = pp1->Prev;
|
|
pp1->Prev = pp2;
|
|
pp1 = pp2;
|
|
} while( pp1 != pp );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void DisposeOutPts( OutPt*& pp )
|
|
{
|
|
if( pp == 0 )
|
|
return;
|
|
|
|
pp->Prev->Next = 0;
|
|
|
|
while( pp )
|
|
{
|
|
OutPt* tmpPp = pp;
|
|
pp = pp->Next;
|
|
delete tmpPp;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline void InitEdge( TEdge* e, TEdge* eNext, TEdge* ePrev, const IntPoint& Pt )
|
|
{
|
|
std::memset( e, 0, sizeof(TEdge) );
|
|
|
|
e->Next = eNext;
|
|
e->Prev = ePrev;
|
|
e->Curr = Pt;
|
|
e->OutIdx = Unassigned;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void InitEdge2( TEdge& e, PolyType Pt )
|
|
{
|
|
if( e.Curr.Y >= e.Next->Curr.Y )
|
|
{
|
|
e.Bot = e.Curr;
|
|
e.Top = e.Next->Curr;
|
|
}
|
|
else
|
|
{
|
|
e.Top = e.Curr;
|
|
e.Bot = e.Next->Curr;
|
|
}
|
|
|
|
SetDx( e );
|
|
e.PolyTyp = Pt;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
TEdge* RemoveEdge( TEdge* e )
|
|
{
|
|
// removes e from double_linked_list (but without removing from memory)
|
|
e->Prev->Next = e->Next;
|
|
e->Next->Prev = e->Prev;
|
|
TEdge* result = e->Next;
|
|
e->Prev = 0; // flag as removed (see ClipperBase.Clear)
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline void ReverseHorizontal( TEdge& e )
|
|
{
|
|
// swap horizontal edges' Top and Bottom x's so they follow the natural
|
|
// progression of the bounds - ie so their xbots will align with the
|
|
// adjoining lower edge. [Helpful in the ProcessHorizontal() method.]
|
|
std::swap( e.Top.X, e.Bot.X );
|
|
|
|
#ifdef use_xyz
|
|
std::swap( e.Top.Z, e.Bot.Z );
|
|
#endif
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void SwapPoints( IntPoint& pt1, IntPoint& pt2 )
|
|
{
|
|
IntPoint tmp = pt1;
|
|
|
|
pt1 = pt2;
|
|
pt2 = tmp;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool GetOverlapSegment( IntPoint pt1a, IntPoint pt1b, IntPoint pt2a,
|
|
IntPoint pt2b, IntPoint& pt1, IntPoint& pt2 )
|
|
{
|
|
// precondition: segments are Collinear.
|
|
if( Abs( pt1a.X - pt1b.X ) > Abs( pt1a.Y - pt1b.Y ) )
|
|
{
|
|
if( pt1a.X > pt1b.X )
|
|
SwapPoints( pt1a, pt1b );
|
|
|
|
if( pt2a.X > pt2b.X )
|
|
SwapPoints( pt2a, pt2b );
|
|
|
|
if( pt1a.X > pt2a.X )
|
|
pt1 = pt1a;
|
|
else
|
|
pt1 = pt2a;
|
|
|
|
if( pt1b.X < pt2b.X )
|
|
pt2 = pt1b;
|
|
else
|
|
pt2 = pt2b;
|
|
|
|
return pt1.X < pt2.X;
|
|
}
|
|
else
|
|
{
|
|
if( pt1a.Y < pt1b.Y )
|
|
SwapPoints( pt1a, pt1b );
|
|
|
|
if( pt2a.Y < pt2b.Y )
|
|
SwapPoints( pt2a, pt2b );
|
|
|
|
if( pt1a.Y < pt2a.Y )
|
|
pt1 = pt1a;
|
|
else
|
|
pt1 = pt2a;
|
|
|
|
if( pt1b.Y > pt2b.Y )
|
|
pt2 = pt1b;
|
|
else
|
|
pt2 = pt2b;
|
|
|
|
return pt1.Y > pt2.Y;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool FirstIsBottomPt( const OutPt* btmPt1, const OutPt* btmPt2 )
|
|
{
|
|
OutPt* p = btmPt1->Prev;
|
|
|
|
while( (p->Pt == btmPt1->Pt) && (p != btmPt1) )
|
|
p = p->Prev;
|
|
|
|
double dx1p = std::fabs( GetDx( btmPt1->Pt, p->Pt ) );
|
|
p = btmPt1->Next;
|
|
|
|
while( (p->Pt == btmPt1->Pt) && (p != btmPt1) )
|
|
p = p->Next;
|
|
|
|
double dx1n = std::fabs( GetDx( btmPt1->Pt, p->Pt ) );
|
|
|
|
p = btmPt2->Prev;
|
|
|
|
while( (p->Pt == btmPt2->Pt) && (p != btmPt2) )
|
|
p = p->Prev;
|
|
|
|
double dx2p = std::fabs( GetDx( btmPt2->Pt, p->Pt ) );
|
|
p = btmPt2->Next;
|
|
|
|
while( (p->Pt == btmPt2->Pt) && (p != btmPt2) )
|
|
p = p->Next;
|
|
|
|
double dx2n = std::fabs( GetDx( btmPt2->Pt, p->Pt ) );
|
|
|
|
if( std::max( dx1p, dx1n ) == std::max( dx2p, dx2n )
|
|
&& std::min( dx1p, dx1n ) == std::min( dx2p, dx2n ) )
|
|
return Area( btmPt1 ) > 0; // if otherwise identical use orientation
|
|
else
|
|
return (dx1p >= dx2p && dx1p >= dx2n) || (dx1n >= dx2p && dx1n >= dx2n);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutPt* GetBottomPt( OutPt* pp )
|
|
{
|
|
OutPt* dups = 0;
|
|
OutPt* p = pp->Next;
|
|
|
|
while( p != pp )
|
|
{
|
|
if( p->Pt.Y > pp->Pt.Y )
|
|
{
|
|
pp = p;
|
|
dups = 0;
|
|
}
|
|
else if( p->Pt.Y == pp->Pt.Y && p->Pt.X <= pp->Pt.X )
|
|
{
|
|
if( p->Pt.X < pp->Pt.X )
|
|
{
|
|
dups = 0;
|
|
pp = p;
|
|
}
|
|
else
|
|
{
|
|
if( p->Next != pp && p->Prev != pp )
|
|
dups = p;
|
|
}
|
|
}
|
|
|
|
p = p->Next;
|
|
}
|
|
|
|
if( dups )
|
|
{
|
|
// there appears to be at least 2 vertices at BottomPt so ...
|
|
while( dups != p )
|
|
{
|
|
if( !FirstIsBottomPt( p, dups ) )
|
|
pp = dups;
|
|
|
|
dups = dups->Next;
|
|
|
|
while( dups->Pt != pp->Pt )
|
|
dups = dups->Next;
|
|
}
|
|
}
|
|
|
|
return pp;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Pt2IsBetweenPt1AndPt3( const IntPoint pt1,
|
|
const IntPoint pt2, const IntPoint pt3 )
|
|
{
|
|
if( (pt1 == pt3) || (pt1 == pt2) || (pt3 == pt2) )
|
|
return false;
|
|
else if( pt1.X != pt3.X )
|
|
return (pt2.X > pt1.X) == (pt2.X < pt3.X);
|
|
else
|
|
return (pt2.Y > pt1.Y) == (pt2.Y < pt3.Y);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool HorzSegmentsOverlap( cInt seg1a, cInt seg1b, cInt seg2a, cInt seg2b )
|
|
{
|
|
if( seg1a > seg1b )
|
|
std::swap( seg1a, seg1b );
|
|
|
|
if( seg2a > seg2b )
|
|
std::swap( seg2a, seg2b );
|
|
|
|
return (seg1a < seg2b) && (seg2a < seg1b);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
// ClipperBase class methods ...
|
|
// ------------------------------------------------------------------------------
|
|
|
|
ClipperBase::ClipperBase() // constructor
|
|
{
|
|
m_CurrentLM = m_MinimaList.begin(); // begin() == end() here
|
|
m_UseFullRange = false;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
ClipperBase::~ClipperBase() // destructor
|
|
{
|
|
Clear();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void RangeTest( const IntPoint& Pt, bool& useFullRange )
|
|
{
|
|
if( useFullRange )
|
|
{
|
|
if( Pt.X > hiRange || Pt.Y > hiRange || -Pt.X > hiRange || -Pt.Y > hiRange )
|
|
throw clipperException( "Coordinate outside allowed range" );
|
|
}
|
|
else if( Pt.X > loRange|| Pt.Y > loRange || -Pt.X > loRange || -Pt.Y > loRange )
|
|
{
|
|
useFullRange = true;
|
|
RangeTest( Pt, useFullRange );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
TEdge* FindNextLocMin( TEdge* E )
|
|
{
|
|
for( ; ; )
|
|
{
|
|
while( E->Bot != E->Prev->Bot || E->Curr == E->Top )
|
|
E = E->Next;
|
|
|
|
if( !IsHorizontal( *E ) && !IsHorizontal( *E->Prev ) )
|
|
break;
|
|
|
|
while( IsHorizontal( *E->Prev ) )
|
|
E = E->Prev;
|
|
|
|
TEdge* E2 = E;
|
|
|
|
while( IsHorizontal( *E ) )
|
|
E = E->Next;
|
|
|
|
if( E->Top.Y == E->Prev->Bot.Y )
|
|
continue; // ie just an intermediate horz.
|
|
|
|
if( E2->Prev->Bot.X < E->Bot.X )
|
|
E = E2;
|
|
|
|
break;
|
|
}
|
|
|
|
return E;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
TEdge* ClipperBase::ProcessBound( TEdge* E, bool NextIsForward )
|
|
{
|
|
TEdge* Result = E;
|
|
TEdge* Horz = 0;
|
|
|
|
if( E->OutIdx == Skip )
|
|
{
|
|
// if edges still remain in the current bound beyond the skip edge then
|
|
// create another LocMin and call ProcessBound once more
|
|
if( NextIsForward )
|
|
{
|
|
while( E->Top.Y == E->Next->Bot.Y )
|
|
E = E->Next;
|
|
|
|
// don't include top horizontals when parsing a bound a second time,
|
|
// they will be contained in the opposite bound ...
|
|
while( E != Result && IsHorizontal( *E ) )
|
|
E = E->Prev;
|
|
}
|
|
else
|
|
{
|
|
while( E->Top.Y == E->Prev->Bot.Y )
|
|
E = E->Prev;
|
|
|
|
while( E != Result && IsHorizontal( *E ) )
|
|
E = E->Next;
|
|
}
|
|
|
|
if( E == Result )
|
|
{
|
|
if( NextIsForward )
|
|
Result = E->Next;
|
|
else
|
|
Result = E->Prev;
|
|
}
|
|
else
|
|
{
|
|
// there are more edges in the bound beyond result starting with E
|
|
if( NextIsForward )
|
|
E = Result->Next;
|
|
else
|
|
E = Result->Prev;
|
|
|
|
MinimaList::value_type locMin;
|
|
locMin.Y = E->Bot.Y;
|
|
locMin.LeftBound = 0;
|
|
locMin.RightBound = E;
|
|
E->WindDelta = 0;
|
|
Result = ProcessBound( E, NextIsForward );
|
|
m_MinimaList.push_back( locMin );
|
|
}
|
|
|
|
return Result;
|
|
}
|
|
|
|
TEdge* EStart;
|
|
|
|
if( IsHorizontal( *E ) )
|
|
{
|
|
// We need to be careful with open paths because this may not be a
|
|
// true local minima (ie E may be following a skip edge).
|
|
// Also, consecutive horz. edges may start heading left before going right.
|
|
if( NextIsForward )
|
|
EStart = E->Prev;
|
|
else
|
|
EStart = E->Next;
|
|
|
|
if( IsHorizontal( *EStart ) ) // ie an adjoining horizontal skip edge
|
|
{
|
|
if( EStart->Bot.X != E->Bot.X && EStart->Top.X != E->Bot.X )
|
|
ReverseHorizontal( *E );
|
|
}
|
|
else if( EStart->Bot.X != E->Bot.X )
|
|
ReverseHorizontal( *E );
|
|
}
|
|
|
|
EStart = E;
|
|
|
|
if( NextIsForward )
|
|
{
|
|
while( Result->Top.Y == Result->Next->Bot.Y && Result->Next->OutIdx != Skip )
|
|
Result = Result->Next;
|
|
|
|
if( IsHorizontal( *Result ) && Result->Next->OutIdx != Skip )
|
|
{
|
|
// nb: at the top of a bound, horizontals are added to the bound
|
|
// only when the preceding edge attaches to the horizontal's left vertex
|
|
// unless a Skip edge is encountered when that becomes the top divide
|
|
Horz = Result;
|
|
|
|
while( IsHorizontal( *Horz->Prev ) )
|
|
Horz = Horz->Prev;
|
|
|
|
if( Horz->Prev->Top.X > Result->Next->Top.X )
|
|
Result = Horz->Prev;
|
|
}
|
|
|
|
while( E != Result )
|
|
{
|
|
E->NextInLML = E->Next;
|
|
|
|
if( IsHorizontal( *E ) && E != EStart
|
|
&& E->Bot.X != E->Prev->Top.X )
|
|
ReverseHorizontal( *E );
|
|
|
|
E = E->Next;
|
|
}
|
|
|
|
if( IsHorizontal( *E ) && E != EStart && E->Bot.X != E->Prev->Top.X )
|
|
ReverseHorizontal( *E );
|
|
|
|
Result = Result->Next; // move to the edge just beyond current bound
|
|
}
|
|
else
|
|
{
|
|
while( Result->Top.Y == Result->Prev->Bot.Y && Result->Prev->OutIdx != Skip )
|
|
Result = Result->Prev;
|
|
|
|
if( IsHorizontal( *Result ) && Result->Prev->OutIdx != Skip )
|
|
{
|
|
Horz = Result;
|
|
|
|
while( IsHorizontal( *Horz->Next ) )
|
|
Horz = Horz->Next;
|
|
|
|
if( Horz->Next->Top.X == Result->Prev->Top.X
|
|
|| Horz->Next->Top.X > Result->Prev->Top.X )
|
|
Result = Horz->Next;
|
|
}
|
|
|
|
while( E != Result )
|
|
{
|
|
E->NextInLML = E->Prev;
|
|
|
|
if( IsHorizontal( *E ) && E != EStart && E->Bot.X != E->Next->Top.X )
|
|
ReverseHorizontal( *E );
|
|
|
|
E = E->Prev;
|
|
}
|
|
|
|
if( IsHorizontal( *E ) && E != EStart && E->Bot.X != E->Next->Top.X )
|
|
ReverseHorizontal( *E );
|
|
|
|
Result = Result->Prev; // move to the edge just beyond current bound
|
|
}
|
|
|
|
return Result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool ClipperBase::AddPath( const Path& pg, PolyType PolyTyp, bool Closed )
|
|
{
|
|
#ifdef use_lines
|
|
|
|
if( !Closed && PolyTyp == ptClip )
|
|
throw clipperException( "AddPath: Open paths must be subject." );
|
|
|
|
#else
|
|
|
|
if( !Closed )
|
|
throw clipperException( "AddPath: Open paths have been disabled." );
|
|
|
|
#endif
|
|
|
|
int highI = (int) pg.size() - 1;
|
|
|
|
if( Closed )
|
|
while( highI > 0 && (pg[highI] == pg[0]) )
|
|
--highI;
|
|
|
|
|
|
while( highI > 0 && (pg[highI] == pg[highI - 1]) )
|
|
--highI;
|
|
|
|
if( (Closed && highI < 2) || (!Closed && highI < 1) )
|
|
return false;
|
|
|
|
// create a new edge array ...
|
|
TEdge* edges = new TEdge[highI + 1];
|
|
|
|
bool IsFlat = true;
|
|
// 1. Basic (first) edge initialization ...
|
|
try
|
|
{
|
|
edges[1].Curr = pg[1];
|
|
RangeTest( pg[0], m_UseFullRange );
|
|
RangeTest( pg[highI], m_UseFullRange );
|
|
InitEdge( &edges[0], &edges[1], &edges[highI], pg[0] );
|
|
InitEdge( &edges[highI], &edges[0], &edges[highI - 1], pg[highI] );
|
|
|
|
for( int i = highI - 1; i >= 1; --i )
|
|
{
|
|
RangeTest( pg[i], m_UseFullRange );
|
|
InitEdge( &edges[i], &edges[i + 1], &edges[i - 1], pg[i] );
|
|
}
|
|
}
|
|
catch( ... )
|
|
{
|
|
delete [] edges;
|
|
throw; // range test fails
|
|
}
|
|
TEdge* eStart = &edges[0];
|
|
|
|
// 2. Remove duplicate vertices, and (when closed) collinear edges ...
|
|
TEdge* E = eStart, * eLoopStop = eStart;
|
|
|
|
for( ; ; )
|
|
{
|
|
// nb: allows matching start and end points when not Closed ...
|
|
if( E->Curr == E->Next->Curr && (Closed || E->Next != eStart) )
|
|
{
|
|
if( E == E->Next )
|
|
break;
|
|
|
|
if( E == eStart )
|
|
eStart = E->Next;
|
|
|
|
E = RemoveEdge( E );
|
|
eLoopStop = E;
|
|
continue;
|
|
}
|
|
|
|
if( E->Prev == E->Next )
|
|
break; // only two vertices
|
|
else if( Closed
|
|
&& SlopesEqual( E->Prev->Curr, E->Curr, E->Next->Curr, m_UseFullRange )
|
|
&& ( !m_PreserveCollinear
|
|
|| !Pt2IsBetweenPt1AndPt3( E->Prev->Curr, E->Curr, E->Next->Curr ) ) )
|
|
{
|
|
// Collinear edges are allowed for open paths but in closed paths
|
|
// the default is to merge adjacent collinear edges into a single edge.
|
|
// However, if the PreserveCollinear property is enabled, only overlapping
|
|
// collinear edges (ie spikes) will be removed from closed paths.
|
|
if( E == eStart )
|
|
eStart = E->Next;
|
|
|
|
E = RemoveEdge( E );
|
|
E = E->Prev;
|
|
eLoopStop = E;
|
|
continue;
|
|
}
|
|
|
|
E = E->Next;
|
|
|
|
if( (E == eLoopStop) || (!Closed && E->Next == eStart) )
|
|
break;
|
|
}
|
|
|
|
if( ( !Closed && (E == E->Next) ) || ( Closed && (E->Prev == E->Next) ) )
|
|
{
|
|
delete [] edges;
|
|
return false;
|
|
}
|
|
|
|
if( !Closed )
|
|
{
|
|
m_HasOpenPaths = true;
|
|
eStart->Prev->OutIdx = Skip;
|
|
}
|
|
|
|
// 3. Do second stage of edge initialization ...
|
|
E = eStart;
|
|
|
|
do
|
|
{
|
|
InitEdge2( *E, PolyTyp );
|
|
E = E->Next;
|
|
|
|
if( IsFlat && E->Curr.Y != eStart->Curr.Y )
|
|
IsFlat = false;
|
|
} while( E != eStart );
|
|
|
|
// 4. Finally, add edge bounds to LocalMinima list ...
|
|
|
|
// Totally flat paths must be handled differently when adding them
|
|
// to LocalMinima list to avoid endless loops etc ...
|
|
if( IsFlat )
|
|
{
|
|
if( Closed )
|
|
{
|
|
delete [] edges;
|
|
return false;
|
|
}
|
|
|
|
E->Prev->OutIdx = Skip;
|
|
MinimaList::value_type locMin;
|
|
locMin.Y = E->Bot.Y;
|
|
locMin.LeftBound = 0;
|
|
locMin.RightBound = E;
|
|
locMin.RightBound->Side = esRight;
|
|
locMin.RightBound->WindDelta = 0;
|
|
|
|
for( ; ; )
|
|
{
|
|
if( E->Bot.X != E->Prev->Top.X )
|
|
ReverseHorizontal( *E );
|
|
|
|
if( E->Next->OutIdx == Skip )
|
|
break;
|
|
|
|
E->NextInLML = E->Next;
|
|
E = E->Next;
|
|
}
|
|
|
|
m_MinimaList.push_back( locMin );
|
|
m_edges.push_back( edges );
|
|
return true;
|
|
}
|
|
|
|
m_edges.push_back( edges );
|
|
bool leftBoundIsForward;
|
|
TEdge* EMin = 0;
|
|
|
|
// workaround to avoid an endless loop in the while loop below when
|
|
// open paths have matching start and end points ...
|
|
if( E->Prev->Bot == E->Prev->Top )
|
|
E = E->Next;
|
|
|
|
for( ; ; )
|
|
{
|
|
E = FindNextLocMin( E );
|
|
|
|
if( E == EMin )
|
|
break;
|
|
else if( !EMin )
|
|
EMin = E;
|
|
|
|
// E and E.Prev now share a local minima (left aligned if horizontal).
|
|
// Compare their slopes to find which starts which bound ...
|
|
MinimaList::value_type locMin;
|
|
locMin.Y = E->Bot.Y;
|
|
|
|
if( E->Dx < E->Prev->Dx )
|
|
{
|
|
locMin.LeftBound = E->Prev;
|
|
locMin.RightBound = E;
|
|
leftBoundIsForward = false; // Q.nextInLML = Q.prev
|
|
}
|
|
else
|
|
{
|
|
locMin.LeftBound = E;
|
|
locMin.RightBound = E->Prev;
|
|
leftBoundIsForward = true; // Q.nextInLML = Q.next
|
|
}
|
|
|
|
if( !Closed )
|
|
locMin.LeftBound->WindDelta = 0;
|
|
else if( locMin.LeftBound->Next == locMin.RightBound )
|
|
locMin.LeftBound->WindDelta = -1;
|
|
else
|
|
locMin.LeftBound->WindDelta = 1;
|
|
|
|
locMin.RightBound->WindDelta = -locMin.LeftBound->WindDelta;
|
|
|
|
E = ProcessBound( locMin.LeftBound, leftBoundIsForward );
|
|
|
|
if( E->OutIdx == Skip )
|
|
E = ProcessBound( E, leftBoundIsForward );
|
|
|
|
TEdge* E2 = ProcessBound( locMin.RightBound, !leftBoundIsForward );
|
|
|
|
if( E2->OutIdx == Skip )
|
|
E2 = ProcessBound( E2, !leftBoundIsForward );
|
|
|
|
if( locMin.LeftBound->OutIdx == Skip )
|
|
locMin.LeftBound = 0;
|
|
else if( locMin.RightBound->OutIdx == Skip )
|
|
locMin.RightBound = 0;
|
|
|
|
m_MinimaList.push_back( locMin );
|
|
|
|
if( !leftBoundIsForward )
|
|
E = E2;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool ClipperBase::AddPaths( const Paths& ppg, PolyType PolyTyp, bool Closed )
|
|
{
|
|
bool result = false;
|
|
|
|
for( Paths::size_type i = 0; i < ppg.size(); ++i )
|
|
if( AddPath( ppg[i], PolyTyp, Closed ) )
|
|
result = true;
|
|
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::Clear()
|
|
{
|
|
DisposeLocalMinimaList();
|
|
|
|
for( EdgeList::size_type i = 0; i < m_edges.size(); ++i )
|
|
{
|
|
TEdge* edges = m_edges[i];
|
|
delete [] edges;
|
|
}
|
|
|
|
m_edges.clear();
|
|
m_UseFullRange = false;
|
|
m_HasOpenPaths = false;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::Reset()
|
|
{
|
|
m_CurrentLM = m_MinimaList.begin();
|
|
|
|
if( m_CurrentLM == m_MinimaList.end() )
|
|
return; // ie nothing to process
|
|
|
|
std::sort( m_MinimaList.begin(), m_MinimaList.end(), LocMinSorter() );
|
|
|
|
m_Scanbeam = ScanbeamList(); // clears/resets priority_queue
|
|
|
|
// reset all edges ...
|
|
for( MinimaList::iterator lm = m_MinimaList.begin(); lm != m_MinimaList.end(); ++lm )
|
|
{
|
|
InsertScanbeam( lm->Y );
|
|
TEdge* e = lm->LeftBound;
|
|
|
|
if( e )
|
|
{
|
|
e->Curr = e->Bot;
|
|
e->Side = esLeft;
|
|
e->OutIdx = Unassigned;
|
|
}
|
|
|
|
e = lm->RightBound;
|
|
|
|
if( e )
|
|
{
|
|
e->Curr = e->Bot;
|
|
e->Side = esRight;
|
|
e->OutIdx = Unassigned;
|
|
}
|
|
}
|
|
|
|
m_ActiveEdges = 0;
|
|
m_CurrentLM = m_MinimaList.begin();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::DisposeLocalMinimaList()
|
|
{
|
|
m_MinimaList.clear();
|
|
m_CurrentLM = m_MinimaList.begin();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool ClipperBase::PopLocalMinima( cInt Y, const LocalMinimum*& locMin )
|
|
{
|
|
if( m_CurrentLM == m_MinimaList.end() || (*m_CurrentLM).Y != Y )
|
|
return false;
|
|
|
|
locMin = &(*m_CurrentLM);
|
|
++m_CurrentLM;
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
IntRect ClipperBase::GetBounds()
|
|
{
|
|
IntRect result;
|
|
MinimaList::iterator lm = m_MinimaList.begin();
|
|
|
|
if( lm == m_MinimaList.end() )
|
|
{
|
|
result.left = result.top = result.right = result.bottom = 0;
|
|
return result;
|
|
}
|
|
|
|
result.left = lm->LeftBound->Bot.X;
|
|
result.top = lm->LeftBound->Bot.Y;
|
|
result.right = lm->LeftBound->Bot.X;
|
|
result.bottom = lm->LeftBound->Bot.Y;
|
|
|
|
while( lm != m_MinimaList.end() )
|
|
{
|
|
// todo - needs fixing for open paths
|
|
result.bottom = std::max( result.bottom, lm->LeftBound->Bot.Y );
|
|
TEdge* e = lm->LeftBound;
|
|
|
|
for( ; ; )
|
|
{
|
|
TEdge* bottomE = e;
|
|
|
|
while( e->NextInLML )
|
|
{
|
|
if( e->Bot.X < result.left )
|
|
result.left = e->Bot.X;
|
|
|
|
if( e->Bot.X > result.right )
|
|
result.right = e->Bot.X;
|
|
|
|
e = e->NextInLML;
|
|
}
|
|
|
|
result.left = std::min( result.left, e->Bot.X );
|
|
result.right = std::max( result.right, e->Bot.X );
|
|
result.left = std::min( result.left, e->Top.X );
|
|
result.right = std::max( result.right, e->Top.X );
|
|
result.top = std::min( result.top, e->Top.Y );
|
|
|
|
if( bottomE == lm->LeftBound )
|
|
e = lm->RightBound;
|
|
else
|
|
break;
|
|
}
|
|
|
|
++lm;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::InsertScanbeam( const cInt Y )
|
|
{
|
|
m_Scanbeam.push( Y );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool ClipperBase::PopScanbeam( cInt& Y )
|
|
{
|
|
if( m_Scanbeam.empty() )
|
|
return false;
|
|
|
|
Y = m_Scanbeam.top();
|
|
m_Scanbeam.pop();
|
|
|
|
while( !m_Scanbeam.empty() && Y == m_Scanbeam.top() )
|
|
{
|
|
m_Scanbeam.pop();
|
|
} // Pop duplicates.
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::DisposeAllOutRecs()
|
|
{
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i )
|
|
DisposeOutRec( i );
|
|
|
|
m_PolyOuts.clear();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::DisposeOutRec( PolyOutList::size_type index )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[index];
|
|
|
|
if( outRec->Pts )
|
|
DisposeOutPts( outRec->Pts );
|
|
|
|
delete outRec;
|
|
m_PolyOuts[index] = 0;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::DeleteFromAEL( TEdge* e )
|
|
{
|
|
TEdge* AelPrev = e->PrevInAEL;
|
|
TEdge* AelNext = e->NextInAEL;
|
|
|
|
if( !AelPrev && !AelNext && (e != m_ActiveEdges) )
|
|
return; // already deleted
|
|
|
|
if( AelPrev )
|
|
AelPrev->NextInAEL = AelNext;
|
|
else
|
|
m_ActiveEdges = AelNext;
|
|
|
|
if( AelNext )
|
|
AelNext->PrevInAEL = AelPrev;
|
|
|
|
e->NextInAEL = 0;
|
|
e->PrevInAEL = 0;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutRec* ClipperBase::CreateOutRec()
|
|
{
|
|
OutRec* result = new OutRec;
|
|
|
|
result->IsHole = false;
|
|
result->IsOpen = false;
|
|
result->FirstLeft = 0;
|
|
result->Pts = 0;
|
|
result->BottomPt = 0;
|
|
result->PolyNd = 0;
|
|
m_PolyOuts.push_back( result );
|
|
result->Idx = (int) m_PolyOuts.size() - 1;
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::SwapPositionsInAEL( TEdge* Edge1, TEdge* Edge2 )
|
|
{
|
|
// check that one or other edge hasn't already been removed from AEL ...
|
|
if( Edge1->NextInAEL == Edge1->PrevInAEL
|
|
|| Edge2->NextInAEL == Edge2->PrevInAEL )
|
|
return;
|
|
|
|
if( Edge1->NextInAEL == Edge2 )
|
|
{
|
|
TEdge* Next = Edge2->NextInAEL;
|
|
|
|
if( Next )
|
|
Next->PrevInAEL = Edge1;
|
|
|
|
TEdge* Prev = Edge1->PrevInAEL;
|
|
|
|
if( Prev )
|
|
Prev->NextInAEL = Edge2;
|
|
|
|
Edge2->PrevInAEL = Prev;
|
|
Edge2->NextInAEL = Edge1;
|
|
Edge1->PrevInAEL = Edge2;
|
|
Edge1->NextInAEL = Next;
|
|
}
|
|
else if( Edge2->NextInAEL == Edge1 )
|
|
{
|
|
TEdge* Next = Edge1->NextInAEL;
|
|
|
|
if( Next )
|
|
Next->PrevInAEL = Edge2;
|
|
|
|
TEdge* Prev = Edge2->PrevInAEL;
|
|
|
|
if( Prev )
|
|
Prev->NextInAEL = Edge1;
|
|
|
|
Edge1->PrevInAEL = Prev;
|
|
Edge1->NextInAEL = Edge2;
|
|
Edge2->PrevInAEL = Edge1;
|
|
Edge2->NextInAEL = Next;
|
|
}
|
|
else
|
|
{
|
|
TEdge* Next = Edge1->NextInAEL;
|
|
TEdge* Prev = Edge1->PrevInAEL;
|
|
Edge1->NextInAEL = Edge2->NextInAEL;
|
|
|
|
if( Edge1->NextInAEL )
|
|
Edge1->NextInAEL->PrevInAEL = Edge1;
|
|
|
|
Edge1->PrevInAEL = Edge2->PrevInAEL;
|
|
|
|
if( Edge1->PrevInAEL )
|
|
Edge1->PrevInAEL->NextInAEL = Edge1;
|
|
|
|
Edge2->NextInAEL = Next;
|
|
|
|
if( Edge2->NextInAEL )
|
|
Edge2->NextInAEL->PrevInAEL = Edge2;
|
|
|
|
Edge2->PrevInAEL = Prev;
|
|
|
|
if( Edge2->PrevInAEL )
|
|
Edge2->PrevInAEL->NextInAEL = Edge2;
|
|
}
|
|
|
|
if( !Edge1->PrevInAEL )
|
|
m_ActiveEdges = Edge1;
|
|
else if( !Edge2->PrevInAEL )
|
|
m_ActiveEdges = Edge2;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperBase::UpdateEdgeIntoAEL( TEdge*& e )
|
|
{
|
|
if( !e->NextInLML )
|
|
throw clipperException( "UpdateEdgeIntoAEL: invalid call" );
|
|
|
|
e->NextInLML->OutIdx = e->OutIdx;
|
|
TEdge* AelPrev = e->PrevInAEL;
|
|
TEdge* AelNext = e->NextInAEL;
|
|
|
|
if( AelPrev )
|
|
AelPrev->NextInAEL = e->NextInLML;
|
|
else
|
|
m_ActiveEdges = e->NextInLML;
|
|
|
|
if( AelNext )
|
|
AelNext->PrevInAEL = e->NextInLML;
|
|
|
|
e->NextInLML->Side = e->Side;
|
|
e->NextInLML->WindDelta = e->WindDelta;
|
|
e->NextInLML->WindCnt = e->WindCnt;
|
|
e->NextInLML->WindCnt2 = e->WindCnt2;
|
|
e = e->NextInLML;
|
|
e->Curr = e->Bot;
|
|
e->PrevInAEL = AelPrev;
|
|
e->NextInAEL = AelNext;
|
|
|
|
if( !IsHorizontal( *e ) )
|
|
InsertScanbeam( e->Top.Y );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool ClipperBase::LocalMinimaPending()
|
|
{
|
|
return m_CurrentLM != m_MinimaList.end();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
// TClipper methods ...
|
|
// ------------------------------------------------------------------------------
|
|
|
|
Clipper::Clipper( int initOptions ) : ClipperBase() // constructor
|
|
{
|
|
m_ExecuteLocked = false;
|
|
m_UseFullRange = false;
|
|
m_ReverseOutput = ( (initOptions & ioReverseSolution) != 0 );
|
|
m_StrictSimple = ( (initOptions & ioStrictlySimple) != 0 );
|
|
m_PreserveCollinear = ( (initOptions & ioPreserveCollinear) != 0 );
|
|
m_HasOpenPaths = false;
|
|
#ifdef use_xyz
|
|
m_ZFill = 0;
|
|
#endif
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
#ifdef use_xyz
|
|
void Clipper::ZFillFunction( ZFillCallback zFillFunc )
|
|
{
|
|
m_ZFill = zFillFunc;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
#endif
|
|
|
|
bool Clipper::Execute( ClipType clipType, Paths& solution, PolyFillType fillType )
|
|
{
|
|
return Execute( clipType, solution, fillType, fillType );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::Execute( ClipType clipType, PolyTree& polytree, PolyFillType fillType )
|
|
{
|
|
return Execute( clipType, polytree, fillType, fillType );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::Execute( ClipType clipType, Paths& solution,
|
|
PolyFillType subjFillType, PolyFillType clipFillType )
|
|
{
|
|
if( m_ExecuteLocked )
|
|
return false;
|
|
|
|
if( m_HasOpenPaths )
|
|
throw clipperException( "Error: PolyTree struct is needed for open path clipping." );
|
|
|
|
m_ExecuteLocked = true;
|
|
solution.resize( 0 );
|
|
m_SubjFillType = subjFillType;
|
|
m_ClipFillType = clipFillType;
|
|
m_ClipType = clipType;
|
|
m_UsingPolyTree = false;
|
|
bool succeeded = ExecuteInternal();
|
|
|
|
if( succeeded )
|
|
BuildResult( solution );
|
|
|
|
DisposeAllOutRecs();
|
|
m_ExecuteLocked = false;
|
|
return succeeded;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::Execute( ClipType clipType, PolyTree& polytree,
|
|
PolyFillType subjFillType, PolyFillType clipFillType )
|
|
{
|
|
if( m_ExecuteLocked )
|
|
return false;
|
|
|
|
m_ExecuteLocked = true;
|
|
m_SubjFillType = subjFillType;
|
|
m_ClipFillType = clipFillType;
|
|
m_ClipType = clipType;
|
|
m_UsingPolyTree = true;
|
|
bool succeeded = ExecuteInternal();
|
|
|
|
if( succeeded )
|
|
BuildResult2( polytree );
|
|
|
|
DisposeAllOutRecs();
|
|
m_ExecuteLocked = false;
|
|
return succeeded;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::FixHoleLinkage( OutRec& outrec )
|
|
{
|
|
// skip OutRecs that (a) contain outermost polygons or
|
|
// (b) already have the correct owner/child linkage ...
|
|
if( !outrec.FirstLeft
|
|
|| (outrec.IsHole != outrec.FirstLeft->IsHole
|
|
&& outrec.FirstLeft->Pts) )
|
|
return;
|
|
|
|
OutRec* orfl = outrec.FirstLeft;
|
|
|
|
while( orfl && ( (orfl->IsHole == outrec.IsHole) || !orfl->Pts ) )
|
|
orfl = orfl->FirstLeft;
|
|
|
|
outrec.FirstLeft = orfl;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::ExecuteInternal()
|
|
{
|
|
bool succeeded = true;
|
|
|
|
try
|
|
{
|
|
Reset();
|
|
m_Maxima = MaximaList();
|
|
m_SortedEdges = 0;
|
|
|
|
succeeded = true;
|
|
cInt botY, topY;
|
|
|
|
if( !PopScanbeam( botY ) )
|
|
return false;
|
|
|
|
InsertLocalMinimaIntoAEL( botY );
|
|
|
|
while( PopScanbeam( topY ) || LocalMinimaPending() )
|
|
{
|
|
ProcessHorizontals();
|
|
ClearGhostJoins();
|
|
|
|
if( !ProcessIntersections( topY ) )
|
|
{
|
|
succeeded = false;
|
|
break;
|
|
}
|
|
|
|
ProcessEdgesAtTopOfScanbeam( topY );
|
|
botY = topY;
|
|
InsertLocalMinimaIntoAEL( botY );
|
|
}
|
|
}
|
|
catch( ... )
|
|
{
|
|
succeeded = false;
|
|
}
|
|
|
|
if( succeeded )
|
|
{
|
|
// fix orientations ...
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
|
|
if( !outRec->Pts || outRec->IsOpen )
|
|
continue;
|
|
|
|
if( (outRec->IsHole ^ m_ReverseOutput) == (Area( *outRec ) > 0) )
|
|
ReversePolyPtLinks( outRec->Pts );
|
|
}
|
|
|
|
if( !m_Joins.empty() )
|
|
JoinCommonEdges();
|
|
|
|
// unfortunately FixupOutPolygon() must be done after JoinCommonEdges()
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
|
|
if( !outRec->Pts )
|
|
continue;
|
|
|
|
if( outRec->IsOpen )
|
|
FixupOutPolyline( *outRec );
|
|
else
|
|
FixupOutPolygon( *outRec );
|
|
}
|
|
|
|
if( m_StrictSimple )
|
|
DoSimplePolygons();
|
|
}
|
|
|
|
ClearJoins();
|
|
ClearGhostJoins();
|
|
return succeeded;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::SetWindingCount( TEdge& edge )
|
|
{
|
|
TEdge* e = edge.PrevInAEL;
|
|
|
|
// find the edge of the same polytype that immediately preceeds 'edge' in AEL
|
|
while( e && ( (e->PolyTyp != edge.PolyTyp) || (e->WindDelta == 0) ) )
|
|
e = e->PrevInAEL;
|
|
|
|
if( !e )
|
|
{
|
|
if( edge.WindDelta == 0 )
|
|
{
|
|
PolyFillType pft = (edge.PolyTyp == ptSubject ? m_SubjFillType : m_ClipFillType);
|
|
edge.WindCnt = (pft == pftNegative ? -1 : 1);
|
|
}
|
|
else
|
|
edge.WindCnt = edge.WindDelta;
|
|
|
|
edge.WindCnt2 = 0;
|
|
e = m_ActiveEdges; // ie get ready to calc WindCnt2
|
|
}
|
|
else if( edge.WindDelta == 0 && m_ClipType != ctUnion )
|
|
{
|
|
edge.WindCnt = 1;
|
|
edge.WindCnt2 = e->WindCnt2;
|
|
e = e->NextInAEL; // ie get ready to calc WindCnt2
|
|
}
|
|
else if( IsEvenOddFillType( edge ) )
|
|
{
|
|
// EvenOdd filling ...
|
|
if( edge.WindDelta == 0 )
|
|
{
|
|
// are we inside a subj polygon ...
|
|
bool Inside = true;
|
|
TEdge* e2 = e->PrevInAEL;
|
|
|
|
while( e2 )
|
|
{
|
|
if( e2->PolyTyp == e->PolyTyp && e2->WindDelta != 0 )
|
|
Inside = !Inside;
|
|
|
|
e2 = e2->PrevInAEL;
|
|
}
|
|
|
|
edge.WindCnt = (Inside ? 0 : 1);
|
|
}
|
|
else
|
|
{
|
|
edge.WindCnt = edge.WindDelta;
|
|
}
|
|
|
|
edge.WindCnt2 = e->WindCnt2;
|
|
e = e->NextInAEL; // ie get ready to calc WindCnt2
|
|
}
|
|
else
|
|
{
|
|
// nonZero, Positive or Negative filling ...
|
|
if( e->WindCnt * e->WindDelta < 0 )
|
|
{
|
|
// prev edge is 'decreasing' WindCount (WC) toward zero
|
|
// so we're outside the previous polygon ...
|
|
if( Abs( e->WindCnt ) > 1 )
|
|
{
|
|
// outside prev poly but still inside another.
|
|
// when reversing direction of prev poly use the same WC
|
|
if( e->WindDelta * edge.WindDelta < 0 )
|
|
edge.WindCnt = e->WindCnt;
|
|
// otherwise continue to 'decrease' WC ...
|
|
else
|
|
edge.WindCnt = e->WindCnt + edge.WindDelta;
|
|
}
|
|
else
|
|
// now outside all polys of same polytype so set own WC ...
|
|
edge.WindCnt = (edge.WindDelta == 0 ? 1 : edge.WindDelta);
|
|
}
|
|
else
|
|
{
|
|
// prev edge is 'increasing' WindCount (WC) away from zero
|
|
// so we're inside the previous polygon ...
|
|
if( edge.WindDelta == 0 )
|
|
edge.WindCnt = (e->WindCnt < 0 ? e->WindCnt - 1 : e->WindCnt + 1);
|
|
// if wind direction is reversing prev then use same WC
|
|
else if( e->WindDelta * edge.WindDelta < 0 )
|
|
edge.WindCnt = e->WindCnt;
|
|
// otherwise add to WC ...
|
|
else
|
|
edge.WindCnt = e->WindCnt + edge.WindDelta;
|
|
}
|
|
|
|
edge.WindCnt2 = e->WindCnt2;
|
|
e = e->NextInAEL; // ie get ready to calc WindCnt2
|
|
}
|
|
|
|
// update WindCnt2 ...
|
|
if( IsEvenOddAltFillType( edge ) )
|
|
{
|
|
// EvenOdd filling ...
|
|
while( e != &edge )
|
|
{
|
|
if( e->WindDelta != 0 )
|
|
edge.WindCnt2 = (edge.WindCnt2 == 0 ? 1 : 0);
|
|
|
|
e = e->NextInAEL;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// nonZero, Positive or Negative filling ...
|
|
while( e != &edge )
|
|
{
|
|
edge.WindCnt2 += e->WindDelta;
|
|
e = e->NextInAEL;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::IsEvenOddFillType( const TEdge& edge ) const
|
|
{
|
|
if( edge.PolyTyp == ptSubject )
|
|
return m_SubjFillType == pftEvenOdd;
|
|
else
|
|
return m_ClipFillType == pftEvenOdd;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::IsEvenOddAltFillType( const TEdge& edge ) const
|
|
{
|
|
if( edge.PolyTyp == ptSubject )
|
|
return m_ClipFillType == pftEvenOdd;
|
|
else
|
|
return m_SubjFillType == pftEvenOdd;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::IsContributing( const TEdge& edge ) const
|
|
{
|
|
PolyFillType pft, pft2;
|
|
|
|
if( edge.PolyTyp == ptSubject )
|
|
{
|
|
pft = m_SubjFillType;
|
|
pft2 = m_ClipFillType;
|
|
}
|
|
else
|
|
{
|
|
pft = m_ClipFillType;
|
|
pft2 = m_SubjFillType;
|
|
}
|
|
|
|
switch( pft )
|
|
{
|
|
case pftEvenOdd:
|
|
|
|
// return false if a subj line has been flagged as inside a subj polygon
|
|
if( edge.WindDelta == 0 && edge.WindCnt != 1 )
|
|
return false;
|
|
|
|
break;
|
|
|
|
case pftNonZero:
|
|
|
|
if( Abs( edge.WindCnt ) != 1 )
|
|
return false;
|
|
|
|
break;
|
|
|
|
case pftPositive:
|
|
|
|
if( edge.WindCnt != 1 )
|
|
return false;
|
|
|
|
break;
|
|
|
|
default: // pftNegative
|
|
|
|
if( edge.WindCnt != -1 )
|
|
return false;
|
|
}
|
|
|
|
switch( m_ClipType )
|
|
{
|
|
case ctIntersection:
|
|
|
|
switch( pft2 )
|
|
{
|
|
case pftEvenOdd:
|
|
case pftNonZero:
|
|
return edge.WindCnt2 != 0;
|
|
|
|
case pftPositive:
|
|
return edge.WindCnt2 > 0;
|
|
|
|
default:
|
|
return edge.WindCnt2 < 0;
|
|
}
|
|
|
|
break;
|
|
|
|
case ctUnion:
|
|
|
|
switch( pft2 )
|
|
{
|
|
case pftEvenOdd:
|
|
case pftNonZero:
|
|
return edge.WindCnt2 == 0;
|
|
|
|
case pftPositive:
|
|
return edge.WindCnt2 <= 0;
|
|
|
|
default:
|
|
return edge.WindCnt2 >= 0;
|
|
}
|
|
|
|
break;
|
|
|
|
case ctDifference:
|
|
|
|
if( edge.PolyTyp == ptSubject )
|
|
switch( pft2 )
|
|
{
|
|
case pftEvenOdd:
|
|
case pftNonZero:
|
|
return edge.WindCnt2 == 0;
|
|
|
|
case pftPositive:
|
|
return edge.WindCnt2 <= 0;
|
|
|
|
default:
|
|
return edge.WindCnt2 >= 0;
|
|
}
|
|
|
|
|
|
else
|
|
switch( pft2 )
|
|
{
|
|
case pftEvenOdd:
|
|
case pftNonZero:
|
|
return edge.WindCnt2 != 0;
|
|
|
|
case pftPositive:
|
|
return edge.WindCnt2 > 0;
|
|
|
|
default:
|
|
return edge.WindCnt2 < 0;
|
|
}
|
|
|
|
|
|
break;
|
|
|
|
case ctXor:
|
|
|
|
if( edge.WindDelta == 0 ) // XOr always contributing unless open
|
|
switch( pft2 )
|
|
{
|
|
case pftEvenOdd:
|
|
case pftNonZero:
|
|
return edge.WindCnt2 == 0;
|
|
|
|
case pftPositive:
|
|
return edge.WindCnt2 <= 0;
|
|
|
|
default:
|
|
return edge.WindCnt2 >= 0;
|
|
}
|
|
|
|
|
|
else
|
|
return true;
|
|
|
|
break;
|
|
|
|
default:
|
|
return true;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutPt* Clipper::AddLocalMinPoly( TEdge* e1, TEdge* e2, const IntPoint& Pt )
|
|
{
|
|
OutPt* result;
|
|
TEdge* e, * prevE;
|
|
|
|
if( IsHorizontal( *e2 ) || ( e1->Dx > e2->Dx ) )
|
|
{
|
|
result = AddOutPt( e1, Pt );
|
|
e2->OutIdx = e1->OutIdx;
|
|
e1->Side = esLeft;
|
|
e2->Side = esRight;
|
|
e = e1;
|
|
|
|
if( e->PrevInAEL == e2 )
|
|
prevE = e2->PrevInAEL;
|
|
else
|
|
prevE = e->PrevInAEL;
|
|
}
|
|
else
|
|
{
|
|
result = AddOutPt( e2, Pt );
|
|
e1->OutIdx = e2->OutIdx;
|
|
e1->Side = esRight;
|
|
e2->Side = esLeft;
|
|
e = e2;
|
|
|
|
if( e->PrevInAEL == e1 )
|
|
prevE = e1->PrevInAEL;
|
|
else
|
|
prevE = e->PrevInAEL;
|
|
}
|
|
|
|
if( prevE && prevE->OutIdx >= 0 && prevE->Top.Y < Pt.Y && e->Top.Y < Pt.Y )
|
|
{
|
|
cInt xPrev = TopX( *prevE, Pt.Y );
|
|
cInt xE = TopX( *e, Pt.Y );
|
|
|
|
if( xPrev == xE && (e->WindDelta != 0) && (prevE->WindDelta != 0)
|
|
&& SlopesEqual( IntPoint( xPrev, Pt.Y ), prevE->Top, IntPoint( xE, Pt.Y ), e->Top,
|
|
m_UseFullRange ) )
|
|
{
|
|
OutPt* outPt = AddOutPt( prevE, Pt );
|
|
AddJoin( result, outPt, e->Top );
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::AddLocalMaxPoly( TEdge* e1, TEdge* e2, const IntPoint& Pt )
|
|
{
|
|
AddOutPt( e1, Pt );
|
|
|
|
if( e2->WindDelta == 0 )
|
|
AddOutPt( e2, Pt );
|
|
|
|
if( e1->OutIdx == e2->OutIdx )
|
|
{
|
|
e1->OutIdx = Unassigned;
|
|
e2->OutIdx = Unassigned;
|
|
}
|
|
else if( e1->OutIdx < e2->OutIdx )
|
|
AppendPolygon( e1, e2 );
|
|
else
|
|
AppendPolygon( e2, e1 );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::AddEdgeToSEL( TEdge* edge )
|
|
{
|
|
// SEL pointers in PEdge are reused to build a list of horizontal edges.
|
|
// However, we don't need to worry about order with horizontal edge processing.
|
|
if( !m_SortedEdges )
|
|
{
|
|
m_SortedEdges = edge;
|
|
edge->PrevInSEL = 0;
|
|
edge->NextInSEL = 0;
|
|
}
|
|
else
|
|
{
|
|
edge->NextInSEL = m_SortedEdges;
|
|
edge->PrevInSEL = 0;
|
|
m_SortedEdges->PrevInSEL = edge;
|
|
m_SortedEdges = edge;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::PopEdgeFromSEL( TEdge*& edge )
|
|
{
|
|
if( !m_SortedEdges )
|
|
return false;
|
|
|
|
edge = m_SortedEdges;
|
|
DeleteFromSEL( m_SortedEdges );
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::CopyAELToSEL()
|
|
{
|
|
TEdge* e = m_ActiveEdges;
|
|
|
|
m_SortedEdges = e;
|
|
|
|
while( e )
|
|
{
|
|
e->PrevInSEL = e->PrevInAEL;
|
|
e->NextInSEL = e->NextInAEL;
|
|
e = e->NextInAEL;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::AddJoin( OutPt* op1, OutPt* op2, const IntPoint OffPt )
|
|
{
|
|
Join* j = new Join;
|
|
|
|
j->OutPt1 = op1;
|
|
j->OutPt2 = op2;
|
|
j->OffPt = OffPt;
|
|
m_Joins.push_back( j );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::ClearJoins()
|
|
{
|
|
for( JoinList::size_type i = 0; i < m_Joins.size(); i++ )
|
|
delete m_Joins[i];
|
|
|
|
m_Joins.resize( 0 );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::ClearGhostJoins()
|
|
{
|
|
for( JoinList::size_type i = 0; i < m_GhostJoins.size(); i++ )
|
|
delete m_GhostJoins[i];
|
|
|
|
m_GhostJoins.resize( 0 );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::AddGhostJoin( OutPt* op, const IntPoint OffPt )
|
|
{
|
|
Join* j = new Join;
|
|
|
|
j->OutPt1 = op;
|
|
j->OutPt2 = 0;
|
|
j->OffPt = OffPt;
|
|
m_GhostJoins.push_back( j );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::InsertLocalMinimaIntoAEL( const cInt botY )
|
|
{
|
|
const LocalMinimum* lm;
|
|
|
|
while( PopLocalMinima( botY, lm ) )
|
|
{
|
|
TEdge* lb = lm->LeftBound;
|
|
TEdge* rb = lm->RightBound;
|
|
|
|
OutPt* Op1 = 0;
|
|
|
|
if( !lb )
|
|
{
|
|
// nb: don't insert LB into either AEL or SEL
|
|
InsertEdgeIntoAEL( rb, 0 );
|
|
SetWindingCount( *rb );
|
|
|
|
if( IsContributing( *rb ) )
|
|
Op1 = AddOutPt( rb, rb->Bot );
|
|
}
|
|
else if( !rb )
|
|
{
|
|
InsertEdgeIntoAEL( lb, 0 );
|
|
SetWindingCount( *lb );
|
|
|
|
if( IsContributing( *lb ) )
|
|
Op1 = AddOutPt( lb, lb->Bot );
|
|
|
|
InsertScanbeam( lb->Top.Y );
|
|
}
|
|
else
|
|
{
|
|
InsertEdgeIntoAEL( lb, 0 );
|
|
InsertEdgeIntoAEL( rb, lb );
|
|
SetWindingCount( *lb );
|
|
rb->WindCnt = lb->WindCnt;
|
|
rb->WindCnt2 = lb->WindCnt2;
|
|
|
|
if( IsContributing( *lb ) )
|
|
Op1 = AddLocalMinPoly( lb, rb, lb->Bot );
|
|
|
|
InsertScanbeam( lb->Top.Y );
|
|
}
|
|
|
|
if( rb )
|
|
{
|
|
if( IsHorizontal( *rb ) )
|
|
{
|
|
AddEdgeToSEL( rb );
|
|
|
|
if( rb->NextInLML )
|
|
InsertScanbeam( rb->NextInLML->Top.Y );
|
|
}
|
|
else
|
|
InsertScanbeam( rb->Top.Y );
|
|
}
|
|
|
|
if( !lb || !rb )
|
|
continue;
|
|
|
|
// if any output polygons share an edge, they'll need joining later ...
|
|
if( Op1 && IsHorizontal( *rb )
|
|
&& m_GhostJoins.size() > 0 && (rb->WindDelta != 0) )
|
|
{
|
|
for( JoinList::size_type i = 0; i < m_GhostJoins.size(); ++i )
|
|
{
|
|
Join* jr = m_GhostJoins[i];
|
|
|
|
// if the horizontal Rb and a 'ghost' horizontal overlap, then convert
|
|
// the 'ghost' join to a real join ready for later ...
|
|
if( HorzSegmentsOverlap( jr->OutPt1->Pt.X, jr->OffPt.X, rb->Bot.X, rb->Top.X ) )
|
|
AddJoin( jr->OutPt1, Op1, jr->OffPt );
|
|
}
|
|
}
|
|
|
|
if( lb->OutIdx >= 0 && lb->PrevInAEL
|
|
&& lb->PrevInAEL->Curr.X == lb->Bot.X
|
|
&& lb->PrevInAEL->OutIdx >= 0
|
|
&& SlopesEqual( lb->PrevInAEL->Bot, lb->PrevInAEL->Top, lb->Curr, lb->Top,
|
|
m_UseFullRange )
|
|
&& (lb->WindDelta != 0) && (lb->PrevInAEL->WindDelta != 0) )
|
|
{
|
|
OutPt* Op2 = AddOutPt( lb->PrevInAEL, lb->Bot );
|
|
AddJoin( Op1, Op2, lb->Top );
|
|
}
|
|
|
|
if( lb->NextInAEL != rb )
|
|
{
|
|
if( rb->OutIdx >= 0 && rb->PrevInAEL->OutIdx >= 0
|
|
&& SlopesEqual( rb->PrevInAEL->Curr, rb->PrevInAEL->Top, rb->Curr, rb->Top,
|
|
m_UseFullRange )
|
|
&& (rb->WindDelta != 0) && (rb->PrevInAEL->WindDelta != 0) )
|
|
{
|
|
OutPt* Op2 = AddOutPt( rb->PrevInAEL, rb->Bot );
|
|
AddJoin( Op1, Op2, rb->Top );
|
|
}
|
|
|
|
TEdge* e = lb->NextInAEL;
|
|
|
|
if( e )
|
|
{
|
|
while( e != rb )
|
|
{
|
|
// nb: For calculating winding counts etc, IntersectEdges() assumes
|
|
// that param1 will be to the Right of param2 ABOVE the intersection ...
|
|
IntersectEdges( rb, e, lb->Curr ); // order important here
|
|
e = e->NextInAEL;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::DeleteFromSEL( TEdge* e )
|
|
{
|
|
TEdge* SelPrev = e->PrevInSEL;
|
|
TEdge* SelNext = e->NextInSEL;
|
|
|
|
if( !SelPrev && !SelNext && (e != m_SortedEdges) )
|
|
return; // already deleted
|
|
|
|
if( SelPrev )
|
|
SelPrev->NextInSEL = SelNext;
|
|
else
|
|
m_SortedEdges = SelNext;
|
|
|
|
if( SelNext )
|
|
SelNext->PrevInSEL = SelPrev;
|
|
|
|
e->NextInSEL = 0;
|
|
e->PrevInSEL = 0;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
#ifdef use_xyz
|
|
void Clipper::SetZ( IntPoint& pt, TEdge& e1, TEdge& e2 )
|
|
{
|
|
if( pt.Z != 0 || !m_ZFill )
|
|
return;
|
|
else if( pt == e1.Bot )
|
|
pt.Z = e1.Bot.Z;
|
|
else if( pt == e1.Top )
|
|
pt.Z = e1.Top.Z;
|
|
else if( pt == e2.Bot )
|
|
pt.Z = e2.Bot.Z;
|
|
else if( pt == e2.Top )
|
|
pt.Z = e2.Top.Z;
|
|
else
|
|
(*m_ZFill)( e1.Bot, e1.Top, e2.Bot, e2.Top, pt );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
#endif
|
|
|
|
void Clipper::IntersectEdges( TEdge* e1, TEdge* e2, IntPoint& Pt )
|
|
{
|
|
bool e1Contributing = ( e1->OutIdx >= 0 );
|
|
bool e2Contributing = ( e2->OutIdx >= 0 );
|
|
|
|
#ifdef use_xyz
|
|
SetZ( Pt, *e1, *e2 );
|
|
#endif
|
|
|
|
#ifdef use_lines
|
|
|
|
// if either edge is on an OPEN path ...
|
|
if( e1->WindDelta == 0 || e2->WindDelta == 0 )
|
|
{
|
|
// ignore subject-subject open path intersections UNLESS they
|
|
// are both open paths, AND they are both 'contributing maximas' ...
|
|
if( e1->WindDelta == 0 && e2->WindDelta == 0 )
|
|
return;
|
|
|
|
// if intersecting a subj line with a subj poly ...
|
|
else if( e1->PolyTyp == e2->PolyTyp
|
|
&& e1->WindDelta != e2->WindDelta && m_ClipType == ctUnion )
|
|
{
|
|
if( e1->WindDelta == 0 )
|
|
{
|
|
if( e2Contributing )
|
|
{
|
|
AddOutPt( e1, Pt );
|
|
|
|
if( e1Contributing )
|
|
e1->OutIdx = Unassigned;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if( e1Contributing )
|
|
{
|
|
AddOutPt( e2, Pt );
|
|
|
|
if( e2Contributing )
|
|
e2->OutIdx = Unassigned;
|
|
}
|
|
}
|
|
}
|
|
else if( e1->PolyTyp != e2->PolyTyp )
|
|
{
|
|
// toggle subj open path OutIdx on/off when Abs(clip.WndCnt) == 1 ...
|
|
if( (e1->WindDelta == 0) && abs( e2->WindCnt ) == 1
|
|
&& (m_ClipType != ctUnion || e2->WindCnt2 == 0) )
|
|
{
|
|
AddOutPt( e1, Pt );
|
|
|
|
if( e1Contributing )
|
|
e1->OutIdx = Unassigned;
|
|
}
|
|
else if( (e2->WindDelta == 0) && (abs( e1->WindCnt ) == 1)
|
|
&& (m_ClipType != ctUnion || e1->WindCnt2 == 0) )
|
|
{
|
|
AddOutPt( e2, Pt );
|
|
|
|
if( e2Contributing )
|
|
e2->OutIdx = Unassigned;
|
|
}
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
#endif
|
|
|
|
// update winding counts...
|
|
// assumes that e1 will be to the Right of e2 ABOVE the intersection
|
|
if( e1->PolyTyp == e2->PolyTyp )
|
|
{
|
|
if( IsEvenOddFillType( *e1 ) )
|
|
{
|
|
int oldE1WindCnt = e1->WindCnt;
|
|
e1->WindCnt = e2->WindCnt;
|
|
e2->WindCnt = oldE1WindCnt;
|
|
}
|
|
else
|
|
{
|
|
if( e1->WindCnt + e2->WindDelta == 0 )
|
|
e1->WindCnt = -e1->WindCnt;
|
|
else
|
|
e1->WindCnt += e2->WindDelta;
|
|
|
|
if( e2->WindCnt - e1->WindDelta == 0 )
|
|
e2->WindCnt = -e2->WindCnt;
|
|
else
|
|
e2->WindCnt -= e1->WindDelta;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if( !IsEvenOddFillType( *e2 ) )
|
|
e1->WindCnt2 += e2->WindDelta;
|
|
else
|
|
e1->WindCnt2 = ( e1->WindCnt2 == 0 ) ? 1 : 0;
|
|
|
|
if( !IsEvenOddFillType( *e1 ) )
|
|
e2->WindCnt2 -= e1->WindDelta;
|
|
else
|
|
e2->WindCnt2 = ( e2->WindCnt2 == 0 ) ? 1 : 0;
|
|
}
|
|
|
|
PolyFillType e1FillType, e2FillType, e1FillType2, e2FillType2;
|
|
|
|
if( e1->PolyTyp == ptSubject )
|
|
{
|
|
e1FillType = m_SubjFillType;
|
|
e1FillType2 = m_ClipFillType;
|
|
}
|
|
else
|
|
{
|
|
e1FillType = m_ClipFillType;
|
|
e1FillType2 = m_SubjFillType;
|
|
}
|
|
|
|
if( e2->PolyTyp == ptSubject )
|
|
{
|
|
e2FillType = m_SubjFillType;
|
|
e2FillType2 = m_ClipFillType;
|
|
}
|
|
else
|
|
{
|
|
e2FillType = m_ClipFillType;
|
|
e2FillType2 = m_SubjFillType;
|
|
}
|
|
|
|
cInt e1Wc, e2Wc;
|
|
|
|
switch( e1FillType )
|
|
{
|
|
case pftPositive:
|
|
e1Wc = e1->WindCnt; break;
|
|
|
|
case pftNegative:
|
|
e1Wc = -e1->WindCnt; break;
|
|
|
|
default:
|
|
e1Wc = Abs( e1->WindCnt );
|
|
}
|
|
|
|
switch( e2FillType )
|
|
{
|
|
case pftPositive:
|
|
e2Wc = e2->WindCnt; break;
|
|
|
|
case pftNegative:
|
|
e2Wc = -e2->WindCnt; break;
|
|
|
|
default:
|
|
e2Wc = Abs( e2->WindCnt );
|
|
}
|
|
|
|
if( e1Contributing && e2Contributing )
|
|
{
|
|
if( (e1Wc != 0 && e1Wc != 1) || (e2Wc != 0 && e2Wc != 1)
|
|
|| (e1->PolyTyp != e2->PolyTyp && m_ClipType != ctXor) )
|
|
{
|
|
AddLocalMaxPoly( e1, e2, Pt );
|
|
}
|
|
else
|
|
{
|
|
AddOutPt( e1, Pt );
|
|
AddOutPt( e2, Pt );
|
|
SwapSides( *e1, *e2 );
|
|
SwapPolyIndexes( *e1, *e2 );
|
|
}
|
|
}
|
|
else if( e1Contributing )
|
|
{
|
|
if( e2Wc == 0 || e2Wc == 1 )
|
|
{
|
|
AddOutPt( e1, Pt );
|
|
SwapSides( *e1, *e2 );
|
|
SwapPolyIndexes( *e1, *e2 );
|
|
}
|
|
}
|
|
else if( e2Contributing )
|
|
{
|
|
if( e1Wc == 0 || e1Wc == 1 )
|
|
{
|
|
AddOutPt( e2, Pt );
|
|
SwapSides( *e1, *e2 );
|
|
SwapPolyIndexes( *e1, *e2 );
|
|
}
|
|
}
|
|
else if( (e1Wc == 0 || e1Wc == 1) && (e2Wc == 0 || e2Wc == 1) )
|
|
{
|
|
// neither edge is currently contributing ...
|
|
|
|
cInt e1Wc2, e2Wc2;
|
|
|
|
switch( e1FillType2 )
|
|
{
|
|
case pftPositive:
|
|
e1Wc2 = e1->WindCnt2; break;
|
|
|
|
case pftNegative:
|
|
e1Wc2 = -e1->WindCnt2; break;
|
|
|
|
default:
|
|
e1Wc2 = Abs( e1->WindCnt2 );
|
|
}
|
|
|
|
switch( e2FillType2 )
|
|
{
|
|
case pftPositive:
|
|
e2Wc2 = e2->WindCnt2; break;
|
|
|
|
case pftNegative:
|
|
e2Wc2 = -e2->WindCnt2; break;
|
|
|
|
default:
|
|
e2Wc2 = Abs( e2->WindCnt2 );
|
|
}
|
|
|
|
if( e1->PolyTyp != e2->PolyTyp )
|
|
{
|
|
AddLocalMinPoly( e1, e2, Pt );
|
|
}
|
|
else if( e1Wc == 1 && e2Wc == 1 )
|
|
switch( m_ClipType )
|
|
{
|
|
case ctIntersection:
|
|
|
|
if( e1Wc2 > 0 && e2Wc2 > 0 )
|
|
AddLocalMinPoly( e1, e2, Pt );
|
|
|
|
break;
|
|
|
|
case ctUnion:
|
|
|
|
if( e1Wc2 <= 0 && e2Wc2 <= 0 )
|
|
AddLocalMinPoly( e1, e2, Pt );
|
|
|
|
break;
|
|
|
|
case ctDifference:
|
|
|
|
if( ( (e1->PolyTyp == ptClip) && (e1Wc2 > 0) && (e2Wc2 > 0) )
|
|
|| ( (e1->PolyTyp == ptSubject) && (e1Wc2 <= 0) && (e2Wc2 <= 0) ) )
|
|
AddLocalMinPoly( e1, e2, Pt );
|
|
|
|
break;
|
|
|
|
case ctXor:
|
|
AddLocalMinPoly( e1, e2, Pt );
|
|
}
|
|
|
|
|
|
else
|
|
SwapSides( *e1, *e2 );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::SetHoleState( TEdge* e, OutRec* outrec )
|
|
{
|
|
TEdge* e2 = e->PrevInAEL;
|
|
TEdge* eTmp = 0;
|
|
|
|
while( e2 )
|
|
{
|
|
if( e2->OutIdx >= 0 && e2->WindDelta != 0 )
|
|
{
|
|
if( !eTmp )
|
|
eTmp = e2;
|
|
else if( eTmp->OutIdx == e2->OutIdx )
|
|
eTmp = 0;
|
|
}
|
|
|
|
e2 = e2->PrevInAEL;
|
|
}
|
|
|
|
if( !eTmp )
|
|
{
|
|
outrec->FirstLeft = 0;
|
|
outrec->IsHole = false;
|
|
}
|
|
else
|
|
{
|
|
outrec->FirstLeft = m_PolyOuts[eTmp->OutIdx];
|
|
outrec->IsHole = !outrec->FirstLeft->IsHole;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutRec* GetLowermostRec( OutRec* outRec1, OutRec* outRec2 )
|
|
{
|
|
// work out which polygon fragment has the correct hole state ...
|
|
if( !outRec1->BottomPt )
|
|
outRec1->BottomPt = GetBottomPt( outRec1->Pts );
|
|
|
|
if( !outRec2->BottomPt )
|
|
outRec2->BottomPt = GetBottomPt( outRec2->Pts );
|
|
|
|
OutPt* OutPt1 = outRec1->BottomPt;
|
|
OutPt* OutPt2 = outRec2->BottomPt;
|
|
|
|
if( OutPt1->Pt.Y > OutPt2->Pt.Y )
|
|
return outRec1;
|
|
else if( OutPt1->Pt.Y < OutPt2->Pt.Y )
|
|
return outRec2;
|
|
else if( OutPt1->Pt.X < OutPt2->Pt.X )
|
|
return outRec1;
|
|
else if( OutPt1->Pt.X > OutPt2->Pt.X )
|
|
return outRec2;
|
|
else if( OutPt1->Next == OutPt1 )
|
|
return outRec2;
|
|
else if( OutPt2->Next == OutPt2 )
|
|
return outRec1;
|
|
else if( FirstIsBottomPt( OutPt1, OutPt2 ) )
|
|
return outRec1;
|
|
else
|
|
return outRec2;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool OutRec1RightOfOutRec2( OutRec* outRec1, OutRec* outRec2 )
|
|
{
|
|
do
|
|
{
|
|
outRec1 = outRec1->FirstLeft;
|
|
|
|
if( outRec1 == outRec2 )
|
|
return true;
|
|
} while( outRec1 );
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutRec* Clipper::GetOutRec( int Idx )
|
|
{
|
|
OutRec* outrec = m_PolyOuts[Idx];
|
|
|
|
while( outrec != m_PolyOuts[outrec->Idx] )
|
|
outrec = m_PolyOuts[outrec->Idx];
|
|
|
|
return outrec;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::AppendPolygon( TEdge* e1, TEdge* e2 )
|
|
{
|
|
// get the start and ends of both output polygons ...
|
|
OutRec* outRec1 = m_PolyOuts[e1->OutIdx];
|
|
OutRec* outRec2 = m_PolyOuts[e2->OutIdx];
|
|
|
|
OutRec* holeStateRec;
|
|
|
|
if( OutRec1RightOfOutRec2( outRec1, outRec2 ) )
|
|
holeStateRec = outRec2;
|
|
else if( OutRec1RightOfOutRec2( outRec2, outRec1 ) )
|
|
holeStateRec = outRec1;
|
|
else
|
|
holeStateRec = GetLowermostRec( outRec1, outRec2 );
|
|
|
|
// get the start and ends of both output polygons and
|
|
// join e2 poly onto e1 poly and delete pointers to e2 ...
|
|
|
|
OutPt* p1_lft = outRec1->Pts;
|
|
OutPt* p1_rt = p1_lft->Prev;
|
|
OutPt* p2_lft = outRec2->Pts;
|
|
OutPt* p2_rt = p2_lft->Prev;
|
|
|
|
// join e2 poly onto e1 poly and delete pointers to e2 ...
|
|
if( e1->Side == esLeft )
|
|
{
|
|
if( e2->Side == esLeft )
|
|
{
|
|
// z y x a b c
|
|
ReversePolyPtLinks( p2_lft );
|
|
p2_lft->Next = p1_lft;
|
|
p1_lft->Prev = p2_lft;
|
|
p1_rt->Next = p2_rt;
|
|
p2_rt->Prev = p1_rt;
|
|
outRec1->Pts = p2_rt;
|
|
}
|
|
else
|
|
{
|
|
// x y z a b c
|
|
p2_rt->Next = p1_lft;
|
|
p1_lft->Prev = p2_rt;
|
|
p2_lft->Prev = p1_rt;
|
|
p1_rt->Next = p2_lft;
|
|
outRec1->Pts = p2_lft;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if( e2->Side == esRight )
|
|
{
|
|
// a b c z y x
|
|
ReversePolyPtLinks( p2_lft );
|
|
p1_rt->Next = p2_rt;
|
|
p2_rt->Prev = p1_rt;
|
|
p2_lft->Next = p1_lft;
|
|
p1_lft->Prev = p2_lft;
|
|
}
|
|
else
|
|
{
|
|
// a b c x y z
|
|
p1_rt->Next = p2_lft;
|
|
p2_lft->Prev = p1_rt;
|
|
p1_lft->Prev = p2_rt;
|
|
p2_rt->Next = p1_lft;
|
|
}
|
|
}
|
|
|
|
outRec1->BottomPt = 0;
|
|
|
|
if( holeStateRec == outRec2 )
|
|
{
|
|
if( outRec2->FirstLeft != outRec1 )
|
|
outRec1->FirstLeft = outRec2->FirstLeft;
|
|
|
|
outRec1->IsHole = outRec2->IsHole;
|
|
}
|
|
|
|
outRec2->Pts = 0;
|
|
outRec2->BottomPt = 0;
|
|
outRec2->FirstLeft = outRec1;
|
|
|
|
int OKIdx = e1->OutIdx;
|
|
int ObsoleteIdx = e2->OutIdx;
|
|
|
|
e1->OutIdx = Unassigned; // nb: safe because we only get here via AddLocalMaxPoly
|
|
e2->OutIdx = Unassigned;
|
|
|
|
TEdge* e = m_ActiveEdges;
|
|
|
|
while( e )
|
|
{
|
|
if( e->OutIdx == ObsoleteIdx )
|
|
{
|
|
e->OutIdx = OKIdx;
|
|
e->Side = e1->Side;
|
|
break;
|
|
}
|
|
|
|
e = e->NextInAEL;
|
|
}
|
|
|
|
outRec2->Idx = outRec1->Idx;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutPt* Clipper::AddOutPt( TEdge* e, const IntPoint& pt )
|
|
{
|
|
if( e->OutIdx < 0 )
|
|
{
|
|
OutRec* outRec = CreateOutRec();
|
|
outRec->IsOpen = (e->WindDelta == 0);
|
|
OutPt* newOp = new OutPt;
|
|
outRec->Pts = newOp;
|
|
newOp->Idx = outRec->Idx;
|
|
newOp->Pt = pt;
|
|
newOp->Next = newOp;
|
|
newOp->Prev = newOp;
|
|
|
|
if( !outRec->IsOpen )
|
|
SetHoleState( e, outRec );
|
|
|
|
e->OutIdx = outRec->Idx;
|
|
return newOp;
|
|
}
|
|
else
|
|
{
|
|
OutRec* outRec = m_PolyOuts[e->OutIdx];
|
|
// OutRec.Pts is the 'Left-most' point & OutRec.Pts.Prev is the 'Right-most'
|
|
OutPt* op = outRec->Pts;
|
|
|
|
bool ToFront = (e->Side == esLeft);
|
|
|
|
if( ToFront && (pt == op->Pt) )
|
|
return op;
|
|
else if( !ToFront && (pt == op->Prev->Pt) )
|
|
return op->Prev;
|
|
|
|
OutPt* newOp = new OutPt;
|
|
newOp->Idx = outRec->Idx;
|
|
newOp->Pt = pt;
|
|
newOp->Next = op;
|
|
newOp->Prev = op->Prev;
|
|
newOp->Prev->Next = newOp;
|
|
op->Prev = newOp;
|
|
|
|
if( ToFront )
|
|
outRec->Pts = newOp;
|
|
|
|
return newOp;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutPt* Clipper::GetLastOutPt( TEdge* e )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[e->OutIdx];
|
|
|
|
if( e->Side == esLeft )
|
|
return outRec->Pts;
|
|
else
|
|
return outRec->Pts->Prev;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::ProcessHorizontals()
|
|
{
|
|
TEdge* horzEdge;
|
|
|
|
while( PopEdgeFromSEL( horzEdge ) )
|
|
ProcessHorizontal( horzEdge );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline bool IsMinima( TEdge* e )
|
|
{
|
|
return e && (e->Prev->NextInLML != e) && (e->Next->NextInLML != e);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline bool IsMaxima( TEdge* e, const cInt Y )
|
|
{
|
|
return e && e->Top.Y == Y && !e->NextInLML;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline bool IsIntermediate( TEdge* e, const cInt Y )
|
|
{
|
|
return e->Top.Y == Y && e->NextInLML;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
TEdge* GetMaximaPair( TEdge* e )
|
|
{
|
|
if( (e->Next->Top == e->Top) && !e->Next->NextInLML )
|
|
return e->Next;
|
|
else if( (e->Prev->Top == e->Top) && !e->Prev->NextInLML )
|
|
return e->Prev;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
TEdge* GetMaximaPairEx( TEdge* e )
|
|
{
|
|
// as GetMaximaPair() but returns 0 if MaxPair isn't in AEL (unless it's horizontal)
|
|
TEdge* result = GetMaximaPair( e );
|
|
|
|
if( result && ( result->OutIdx == Skip
|
|
|| ( result->NextInAEL == result->PrevInAEL && !IsHorizontal( *result ) ) ) )
|
|
return 0;
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::SwapPositionsInSEL( TEdge* Edge1, TEdge* Edge2 )
|
|
{
|
|
if( !( Edge1->NextInSEL ) && !( Edge1->PrevInSEL ) )
|
|
return;
|
|
|
|
if( !( Edge2->NextInSEL ) && !( Edge2->PrevInSEL ) )
|
|
return;
|
|
|
|
if( Edge1->NextInSEL == Edge2 )
|
|
{
|
|
TEdge* Next = Edge2->NextInSEL;
|
|
|
|
if( Next )
|
|
Next->PrevInSEL = Edge1;
|
|
|
|
TEdge* Prev = Edge1->PrevInSEL;
|
|
|
|
if( Prev )
|
|
Prev->NextInSEL = Edge2;
|
|
|
|
Edge2->PrevInSEL = Prev;
|
|
Edge2->NextInSEL = Edge1;
|
|
Edge1->PrevInSEL = Edge2;
|
|
Edge1->NextInSEL = Next;
|
|
}
|
|
else if( Edge2->NextInSEL == Edge1 )
|
|
{
|
|
TEdge* Next = Edge1->NextInSEL;
|
|
|
|
if( Next )
|
|
Next->PrevInSEL = Edge2;
|
|
|
|
TEdge* Prev = Edge2->PrevInSEL;
|
|
|
|
if( Prev )
|
|
Prev->NextInSEL = Edge1;
|
|
|
|
Edge1->PrevInSEL = Prev;
|
|
Edge1->NextInSEL = Edge2;
|
|
Edge2->PrevInSEL = Edge1;
|
|
Edge2->NextInSEL = Next;
|
|
}
|
|
else
|
|
{
|
|
TEdge* Next = Edge1->NextInSEL;
|
|
TEdge* Prev = Edge1->PrevInSEL;
|
|
Edge1->NextInSEL = Edge2->NextInSEL;
|
|
|
|
if( Edge1->NextInSEL )
|
|
Edge1->NextInSEL->PrevInSEL = Edge1;
|
|
|
|
Edge1->PrevInSEL = Edge2->PrevInSEL;
|
|
|
|
if( Edge1->PrevInSEL )
|
|
Edge1->PrevInSEL->NextInSEL = Edge1;
|
|
|
|
Edge2->NextInSEL = Next;
|
|
|
|
if( Edge2->NextInSEL )
|
|
Edge2->NextInSEL->PrevInSEL = Edge2;
|
|
|
|
Edge2->PrevInSEL = Prev;
|
|
|
|
if( Edge2->PrevInSEL )
|
|
Edge2->PrevInSEL->NextInSEL = Edge2;
|
|
}
|
|
|
|
if( !Edge1->PrevInSEL )
|
|
m_SortedEdges = Edge1;
|
|
else if( !Edge2->PrevInSEL )
|
|
m_SortedEdges = Edge2;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
TEdge* GetNextInAEL( TEdge* e, Direction dir )
|
|
{
|
|
return dir == dLeftToRight ? e->NextInAEL : e->PrevInAEL;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void GetHorzDirection( TEdge& HorzEdge, Direction& Dir, cInt& Left, cInt& Right )
|
|
{
|
|
if( HorzEdge.Bot.X < HorzEdge.Top.X )
|
|
{
|
|
Left = HorzEdge.Bot.X;
|
|
Right = HorzEdge.Top.X;
|
|
Dir = dLeftToRight;
|
|
}
|
|
else
|
|
{
|
|
Left = HorzEdge.Top.X;
|
|
Right = HorzEdge.Bot.X;
|
|
Dir = dRightToLeft;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------
|
|
|
|
/*******************************************************************************
|
|
* Notes: Horizontal edges (HEs) at scanline intersections (ie at the Top or *
|
|
* Bottom of a scanbeam) are processed as if layered. The order in which HEs *
|
|
* are processed doesn't matter. HEs intersect with other HE Bot.Xs only [#] *
|
|
* (or they could intersect with Top.Xs only, ie EITHER Bot.Xs OR Top.Xs), *
|
|
* and with other non-horizontal edges [*]. Once these intersections are *
|
|
* processed, intermediate HEs then 'promote' the Edge above (NextInLML) into *
|
|
* the AEL. These 'promoted' edges may in turn intersect [%] with other HEs. *
|
|
*******************************************************************************/
|
|
|
|
void Clipper::ProcessHorizontal( TEdge* horzEdge )
|
|
{
|
|
Direction dir;
|
|
cInt horzLeft, horzRight;
|
|
bool IsOpen = (horzEdge->WindDelta == 0);
|
|
|
|
GetHorzDirection( *horzEdge, dir, horzLeft, horzRight );
|
|
|
|
TEdge* eLastHorz = horzEdge, * eMaxPair = 0;
|
|
|
|
while( eLastHorz->NextInLML && IsHorizontal( *eLastHorz->NextInLML ) )
|
|
eLastHorz = eLastHorz->NextInLML;
|
|
|
|
if( !eLastHorz->NextInLML )
|
|
eMaxPair = GetMaximaPair( eLastHorz );
|
|
|
|
MaximaList::const_iterator maxIt;
|
|
MaximaList::const_reverse_iterator maxRit;
|
|
|
|
if( m_Maxima.size() > 0 )
|
|
{
|
|
// get the first maxima in range (X) ...
|
|
if( dir == dLeftToRight )
|
|
{
|
|
maxIt = m_Maxima.begin();
|
|
|
|
while( maxIt != m_Maxima.end() && *maxIt <= horzEdge->Bot.X )
|
|
maxIt++;
|
|
|
|
if( maxIt != m_Maxima.end() && *maxIt >= eLastHorz->Top.X )
|
|
maxIt = m_Maxima.end();
|
|
}
|
|
else
|
|
{
|
|
maxRit = m_Maxima.rbegin();
|
|
|
|
while( maxRit != m_Maxima.rend() && *maxRit > horzEdge->Bot.X )
|
|
maxRit++;
|
|
|
|
if( maxRit != m_Maxima.rend() && *maxRit <= eLastHorz->Top.X )
|
|
maxRit = m_Maxima.rend();
|
|
}
|
|
}
|
|
|
|
OutPt* op1 = 0;
|
|
|
|
for( ; ; ) // loop through consec. horizontal edges
|
|
{
|
|
bool IsLastHorz = (horzEdge == eLastHorz);
|
|
TEdge* e = GetNextInAEL( horzEdge, dir );
|
|
|
|
while( e )
|
|
{
|
|
// this code block inserts extra coords into horizontal edges (in output
|
|
// polygons) whereever maxima touch these horizontal edges. This helps
|
|
// 'simplifying' polygons (ie if the Simplify property is set).
|
|
if( m_Maxima.size() > 0 )
|
|
{
|
|
if( dir == dLeftToRight )
|
|
{
|
|
while( maxIt != m_Maxima.end() && *maxIt < e->Curr.X )
|
|
{
|
|
if( horzEdge->OutIdx >= 0 && !IsOpen )
|
|
AddOutPt( horzEdge, IntPoint( *maxIt, horzEdge->Bot.Y ) );
|
|
|
|
maxIt++;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
while( maxRit != m_Maxima.rend() && *maxRit > e->Curr.X )
|
|
{
|
|
if( horzEdge->OutIdx >= 0 && !IsOpen )
|
|
AddOutPt( horzEdge, IntPoint( *maxRit, horzEdge->Bot.Y ) );
|
|
|
|
maxRit++;
|
|
}
|
|
}
|
|
}
|
|
|
|
;
|
|
|
|
if( (dir == dLeftToRight && e->Curr.X > horzRight)
|
|
|| (dir == dRightToLeft && e->Curr.X < horzLeft) )
|
|
break;
|
|
|
|
// Also break if we've got to the end of an intermediate horizontal edge ...
|
|
// nb: Smaller Dx's are to the right of larger Dx's ABOVE the horizontal.
|
|
if( e->Curr.X == horzEdge->Top.X && horzEdge->NextInLML
|
|
&& e->Dx < horzEdge->NextInLML->Dx )
|
|
break;
|
|
|
|
if( horzEdge->OutIdx >= 0 && !IsOpen ) // note: may be done multiple times
|
|
{
|
|
#ifdef use_xyz
|
|
|
|
if( dir == dLeftToRight )
|
|
SetZ( e->Curr, *horzEdge, *e );
|
|
else
|
|
SetZ( e->Curr, *e, *horzEdge );
|
|
|
|
#endif
|
|
op1 = AddOutPt( horzEdge, e->Curr );
|
|
TEdge* eNextHorz = m_SortedEdges;
|
|
|
|
while( eNextHorz )
|
|
{
|
|
if( eNextHorz->OutIdx >= 0
|
|
&& HorzSegmentsOverlap( horzEdge->Bot.X,
|
|
horzEdge->Top.X, eNextHorz->Bot.X, eNextHorz->Top.X ) )
|
|
{
|
|
OutPt* op2 = GetLastOutPt( eNextHorz );
|
|
AddJoin( op2, op1, eNextHorz->Top );
|
|
}
|
|
|
|
eNextHorz = eNextHorz->NextInSEL;
|
|
}
|
|
|
|
AddGhostJoin( op1, horzEdge->Bot );
|
|
}
|
|
|
|
// OK, so far we're still in range of the horizontal Edge but make sure
|
|
// we're at the last of consec. horizontals when matching with eMaxPair
|
|
if( e == eMaxPair && IsLastHorz )
|
|
{
|
|
if( horzEdge->OutIdx >= 0 )
|
|
AddLocalMaxPoly( horzEdge, eMaxPair, horzEdge->Top );
|
|
|
|
DeleteFromAEL( horzEdge );
|
|
DeleteFromAEL( eMaxPair );
|
|
return;
|
|
}
|
|
|
|
if( dir == dLeftToRight )
|
|
{
|
|
IntPoint Pt = IntPoint( e->Curr.X, horzEdge->Curr.Y );
|
|
IntersectEdges( horzEdge, e, Pt );
|
|
}
|
|
else
|
|
{
|
|
IntPoint Pt = IntPoint( e->Curr.X, horzEdge->Curr.Y );
|
|
IntersectEdges( e, horzEdge, Pt );
|
|
}
|
|
|
|
TEdge* eNext = GetNextInAEL( e, dir );
|
|
SwapPositionsInAEL( horzEdge, e );
|
|
e = eNext;
|
|
} // end while(e)
|
|
|
|
// Break out of loop if HorzEdge.NextInLML is not also horizontal ...
|
|
if( !horzEdge->NextInLML || !IsHorizontal( *horzEdge->NextInLML ) )
|
|
break;
|
|
|
|
UpdateEdgeIntoAEL( horzEdge );
|
|
|
|
if( horzEdge->OutIdx >= 0 )
|
|
AddOutPt( horzEdge, horzEdge->Bot );
|
|
|
|
GetHorzDirection( *horzEdge, dir, horzLeft, horzRight );
|
|
} // end for (;;)
|
|
|
|
if( horzEdge->OutIdx >= 0 && !op1 )
|
|
{
|
|
op1 = GetLastOutPt( horzEdge );
|
|
TEdge* eNextHorz = m_SortedEdges;
|
|
|
|
while( eNextHorz )
|
|
{
|
|
if( eNextHorz->OutIdx >= 0
|
|
&& HorzSegmentsOverlap( horzEdge->Bot.X,
|
|
horzEdge->Top.X, eNextHorz->Bot.X, eNextHorz->Top.X ) )
|
|
{
|
|
OutPt* op2 = GetLastOutPt( eNextHorz );
|
|
AddJoin( op2, op1, eNextHorz->Top );
|
|
}
|
|
|
|
eNextHorz = eNextHorz->NextInSEL;
|
|
}
|
|
|
|
AddGhostJoin( op1, horzEdge->Top );
|
|
}
|
|
|
|
if( horzEdge->NextInLML )
|
|
{
|
|
if( horzEdge->OutIdx >= 0 )
|
|
{
|
|
op1 = AddOutPt( horzEdge, horzEdge->Top );
|
|
UpdateEdgeIntoAEL( horzEdge );
|
|
|
|
if( horzEdge->WindDelta == 0 )
|
|
return;
|
|
|
|
// nb: HorzEdge is no longer horizontal here
|
|
TEdge* ePrev = horzEdge->PrevInAEL;
|
|
TEdge* eNext = horzEdge->NextInAEL;
|
|
|
|
if( ePrev && ePrev->Curr.X == horzEdge->Bot.X
|
|
&& ePrev->Curr.Y == horzEdge->Bot.Y && ePrev->WindDelta != 0
|
|
&& ( ePrev->OutIdx >= 0 && ePrev->Curr.Y > ePrev->Top.Y
|
|
&& SlopesEqual( *horzEdge, *ePrev, m_UseFullRange ) ) )
|
|
{
|
|
OutPt* op2 = AddOutPt( ePrev, horzEdge->Bot );
|
|
AddJoin( op1, op2, horzEdge->Top );
|
|
}
|
|
else if( eNext && eNext->Curr.X == horzEdge->Bot.X
|
|
&& eNext->Curr.Y == horzEdge->Bot.Y && eNext->WindDelta != 0
|
|
&& eNext->OutIdx >= 0 && eNext->Curr.Y > eNext->Top.Y
|
|
&& SlopesEqual( *horzEdge, *eNext, m_UseFullRange ) )
|
|
{
|
|
OutPt* op2 = AddOutPt( eNext, horzEdge->Bot );
|
|
AddJoin( op1, op2, horzEdge->Top );
|
|
}
|
|
}
|
|
else
|
|
UpdateEdgeIntoAEL( horzEdge );
|
|
}
|
|
else
|
|
{
|
|
if( horzEdge->OutIdx >= 0 )
|
|
AddOutPt( horzEdge, horzEdge->Top );
|
|
|
|
DeleteFromAEL( horzEdge );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::ProcessIntersections( const cInt topY )
|
|
{
|
|
if( !m_ActiveEdges )
|
|
return true;
|
|
|
|
try
|
|
{
|
|
BuildIntersectList( topY );
|
|
size_t IlSize = m_IntersectList.size();
|
|
|
|
if( IlSize == 0 )
|
|
return true;
|
|
|
|
if( IlSize == 1 || FixupIntersectionOrder() )
|
|
ProcessIntersectList();
|
|
else
|
|
return false;
|
|
}
|
|
catch( ... )
|
|
{
|
|
m_SortedEdges = 0;
|
|
DisposeIntersectNodes();
|
|
throw clipperException( "ProcessIntersections error" );
|
|
}
|
|
m_SortedEdges = 0;
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::DisposeIntersectNodes()
|
|
{
|
|
for( size_t i = 0; i < m_IntersectList.size(); ++i )
|
|
delete m_IntersectList[i];
|
|
|
|
m_IntersectList.clear();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::BuildIntersectList( const cInt topY )
|
|
{
|
|
if( !m_ActiveEdges )
|
|
return;
|
|
|
|
// prepare for sorting ...
|
|
TEdge* e = m_ActiveEdges;
|
|
m_SortedEdges = e;
|
|
|
|
while( e )
|
|
{
|
|
e->PrevInSEL = e->PrevInAEL;
|
|
e->NextInSEL = e->NextInAEL;
|
|
e->Curr.X = TopX( *e, topY );
|
|
e = e->NextInAEL;
|
|
}
|
|
|
|
// bubblesort ...
|
|
bool isModified;
|
|
|
|
do
|
|
{
|
|
isModified = false;
|
|
e = m_SortedEdges;
|
|
|
|
while( e->NextInSEL )
|
|
{
|
|
TEdge* eNext = e->NextInSEL;
|
|
IntPoint Pt;
|
|
|
|
if( e->Curr.X > eNext->Curr.X )
|
|
{
|
|
IntersectPoint( *e, *eNext, Pt );
|
|
|
|
if( Pt.Y < topY )
|
|
Pt = IntPoint( TopX( *e, topY ), topY );
|
|
|
|
IntersectNode* newNode = new IntersectNode;
|
|
newNode->Edge1 = e;
|
|
newNode->Edge2 = eNext;
|
|
newNode->Pt = Pt;
|
|
m_IntersectList.push_back( newNode );
|
|
|
|
SwapPositionsInSEL( e, eNext );
|
|
isModified = true;
|
|
}
|
|
else
|
|
e = eNext;
|
|
}
|
|
|
|
if( e->PrevInSEL )
|
|
e->PrevInSEL->NextInSEL = 0;
|
|
else
|
|
break;
|
|
} while( isModified );
|
|
|
|
m_SortedEdges = 0; // important
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
|
|
void Clipper::ProcessIntersectList()
|
|
{
|
|
for( size_t i = 0; i < m_IntersectList.size(); ++i )
|
|
{
|
|
IntersectNode* iNode = m_IntersectList[i];
|
|
{
|
|
IntersectEdges( iNode->Edge1, iNode->Edge2, iNode->Pt );
|
|
SwapPositionsInAEL( iNode->Edge1, iNode->Edge2 );
|
|
}
|
|
delete iNode;
|
|
}
|
|
|
|
m_IntersectList.clear();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool IntersectListSort( IntersectNode* node1, IntersectNode* node2 )
|
|
{
|
|
return node2->Pt.Y < node1->Pt.Y;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline bool EdgesAdjacent( const IntersectNode& inode )
|
|
{
|
|
return (inode.Edge1->NextInSEL == inode.Edge2)
|
|
|| (inode.Edge1->PrevInSEL == inode.Edge2);
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::FixupIntersectionOrder()
|
|
{
|
|
// pre-condition: intersections are sorted Bottom-most first.
|
|
// Now it's crucial that intersections are made only between adjacent edges,
|
|
// so to ensure this the order of intersections may need adjusting ...
|
|
CopyAELToSEL();
|
|
std::sort( m_IntersectList.begin(), m_IntersectList.end(), IntersectListSort );
|
|
size_t cnt = m_IntersectList.size();
|
|
|
|
for( size_t i = 0; i < cnt; ++i )
|
|
{
|
|
if( !EdgesAdjacent( *m_IntersectList[i] ) )
|
|
{
|
|
size_t j = i + 1;
|
|
|
|
while( j < cnt && !EdgesAdjacent( *m_IntersectList[j] ) )
|
|
j++;
|
|
|
|
if( j == cnt )
|
|
return false;
|
|
|
|
std::swap( m_IntersectList[i], m_IntersectList[j] );
|
|
}
|
|
|
|
SwapPositionsInSEL( m_IntersectList[i]->Edge1, m_IntersectList[i]->Edge2 );
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::DoMaxima( TEdge* e )
|
|
{
|
|
TEdge* eMaxPair = GetMaximaPairEx( e );
|
|
|
|
if( !eMaxPair )
|
|
{
|
|
if( e->OutIdx >= 0 )
|
|
AddOutPt( e, e->Top );
|
|
|
|
DeleteFromAEL( e );
|
|
return;
|
|
}
|
|
|
|
TEdge* eNext = e->NextInAEL;
|
|
|
|
while( eNext && eNext != eMaxPair )
|
|
{
|
|
IntersectEdges( e, eNext, e->Top );
|
|
SwapPositionsInAEL( e, eNext );
|
|
eNext = e->NextInAEL;
|
|
}
|
|
|
|
if( e->OutIdx == Unassigned && eMaxPair->OutIdx == Unassigned )
|
|
{
|
|
DeleteFromAEL( e );
|
|
DeleteFromAEL( eMaxPair );
|
|
}
|
|
else if( e->OutIdx >= 0 && eMaxPair->OutIdx >= 0 )
|
|
{
|
|
if( e->OutIdx >= 0 )
|
|
AddLocalMaxPoly( e, eMaxPair, e->Top );
|
|
|
|
DeleteFromAEL( e );
|
|
DeleteFromAEL( eMaxPair );
|
|
}
|
|
|
|
#ifdef use_lines
|
|
else if( e->WindDelta == 0 )
|
|
{
|
|
if( e->OutIdx >= 0 )
|
|
{
|
|
AddOutPt( e, e->Top );
|
|
e->OutIdx = Unassigned;
|
|
}
|
|
|
|
DeleteFromAEL( e );
|
|
|
|
if( eMaxPair->OutIdx >= 0 )
|
|
{
|
|
AddOutPt( eMaxPair, e->Top );
|
|
eMaxPair->OutIdx = Unassigned;
|
|
}
|
|
|
|
DeleteFromAEL( eMaxPair );
|
|
}
|
|
#endif
|
|
else
|
|
throw clipperException( "DoMaxima error" );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::ProcessEdgesAtTopOfScanbeam( const cInt topY )
|
|
{
|
|
TEdge* e = m_ActiveEdges;
|
|
|
|
while( e )
|
|
{
|
|
// 1. process maxima, treating them as if they're 'bent' horizontal edges,
|
|
// but exclude maxima with horizontal edges. nb: e can't be a horizontal.
|
|
bool IsMaximaEdge = IsMaxima( e, topY );
|
|
|
|
if( IsMaximaEdge )
|
|
{
|
|
TEdge* eMaxPair = GetMaximaPairEx( e );
|
|
IsMaximaEdge = ( !eMaxPair || !IsHorizontal( *eMaxPair ) );
|
|
}
|
|
|
|
if( IsMaximaEdge )
|
|
{
|
|
if( m_StrictSimple )
|
|
m_Maxima.push_back( e->Top.X );
|
|
|
|
TEdge* ePrev = e->PrevInAEL;
|
|
DoMaxima( e );
|
|
|
|
if( !ePrev )
|
|
e = m_ActiveEdges;
|
|
else
|
|
e = ePrev->NextInAEL;
|
|
}
|
|
else
|
|
{
|
|
// 2. promote horizontal edges, otherwise update Curr.X and Curr.Y ...
|
|
if( IsIntermediate( e, topY ) && IsHorizontal( *e->NextInLML ) )
|
|
{
|
|
UpdateEdgeIntoAEL( e );
|
|
|
|
if( e->OutIdx >= 0 )
|
|
AddOutPt( e, e->Bot );
|
|
|
|
AddEdgeToSEL( e );
|
|
}
|
|
else
|
|
{
|
|
e->Curr.X = TopX( *e, topY );
|
|
e->Curr.Y = topY;
|
|
#ifdef use_xyz
|
|
e->Curr.Z = topY == e->Top.Y ? e->Top.Z : (topY == e->Bot.Y ? e->Bot.Z : 0);
|
|
#endif
|
|
}
|
|
|
|
// When StrictlySimple and 'e' is being touched by another edge, then
|
|
// make sure both edges have a vertex here ...
|
|
if( m_StrictSimple )
|
|
{
|
|
TEdge* ePrev = e->PrevInAEL;
|
|
|
|
if( (e->OutIdx >= 0) && (e->WindDelta != 0) && ePrev && (ePrev->OutIdx >= 0)
|
|
&& (ePrev->Curr.X == e->Curr.X) && (ePrev->WindDelta != 0) )
|
|
{
|
|
IntPoint pt = e->Curr;
|
|
#ifdef use_xyz
|
|
SetZ( pt, *ePrev, *e );
|
|
#endif
|
|
OutPt* op = AddOutPt( ePrev, pt );
|
|
OutPt* op2 = AddOutPt( e, pt );
|
|
AddJoin( op, op2, pt ); // StrictlySimple (type-3) join
|
|
}
|
|
}
|
|
|
|
e = e->NextInAEL;
|
|
}
|
|
}
|
|
|
|
// 3. Process horizontals at the Top of the scanbeam ...
|
|
m_Maxima.sort();
|
|
ProcessHorizontals();
|
|
m_Maxima.clear();
|
|
|
|
// 4. Promote intermediate vertices ...
|
|
e = m_ActiveEdges;
|
|
|
|
while( e )
|
|
{
|
|
if( IsIntermediate( e, topY ) )
|
|
{
|
|
OutPt* op = 0;
|
|
|
|
if( e->OutIdx >= 0 )
|
|
op = AddOutPt( e, e->Top );
|
|
|
|
UpdateEdgeIntoAEL( e );
|
|
|
|
// if output polygons share an edge, they'll need joining later ...
|
|
TEdge* ePrev = e->PrevInAEL;
|
|
TEdge* eNext = e->NextInAEL;
|
|
|
|
if( ePrev && ePrev->Curr.X == e->Bot.X
|
|
&& ePrev->Curr.Y == e->Bot.Y && op
|
|
&& ePrev->OutIdx >= 0 && ePrev->Curr.Y > ePrev->Top.Y
|
|
&& SlopesEqual( e->Curr, e->Top, ePrev->Curr, ePrev->Top, m_UseFullRange )
|
|
&& (e->WindDelta != 0) && (ePrev->WindDelta != 0) )
|
|
{
|
|
OutPt* op2 = AddOutPt( ePrev, e->Bot );
|
|
AddJoin( op, op2, e->Top );
|
|
}
|
|
else if( eNext && eNext->Curr.X == e->Bot.X
|
|
&& eNext->Curr.Y == e->Bot.Y && op
|
|
&& eNext->OutIdx >= 0 && eNext->Curr.Y > eNext->Top.Y
|
|
&& SlopesEqual( e->Curr, e->Top, eNext->Curr, eNext->Top, m_UseFullRange )
|
|
&& (e->WindDelta != 0) && (eNext->WindDelta != 0) )
|
|
{
|
|
OutPt* op2 = AddOutPt( eNext, e->Bot );
|
|
AddJoin( op, op2, e->Top );
|
|
}
|
|
}
|
|
|
|
e = e->NextInAEL;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::FixupOutPolyline( OutRec& outrec )
|
|
{
|
|
OutPt* pp = outrec.Pts;
|
|
OutPt* lastPP = pp->Prev;
|
|
|
|
while( pp != lastPP )
|
|
{
|
|
pp = pp->Next;
|
|
|
|
if( pp->Pt == pp->Prev->Pt )
|
|
{
|
|
if( pp == lastPP )
|
|
lastPP = pp->Prev;
|
|
|
|
OutPt* tmpPP = pp->Prev;
|
|
tmpPP->Next = pp->Next;
|
|
pp->Next->Prev = tmpPP;
|
|
delete pp;
|
|
pp = tmpPP;
|
|
}
|
|
}
|
|
|
|
if( pp == pp->Prev )
|
|
{
|
|
DisposeOutPts( pp );
|
|
outrec.Pts = 0;
|
|
return;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::FixupOutPolygon( OutRec& outrec )
|
|
{
|
|
// FixupOutPolygon() - removes duplicate points and simplifies consecutive
|
|
// parallel edges by removing the middle vertex.
|
|
OutPt* lastOK = 0;
|
|
|
|
outrec.BottomPt = 0;
|
|
OutPt* pp = outrec.Pts;
|
|
bool preserveCol = m_PreserveCollinear || m_StrictSimple;
|
|
|
|
for( ; ; )
|
|
{
|
|
if( pp->Prev == pp || pp->Prev == pp->Next )
|
|
{
|
|
DisposeOutPts( pp );
|
|
outrec.Pts = 0;
|
|
return;
|
|
}
|
|
|
|
// test for duplicate points and collinear edges ...
|
|
if( (pp->Pt == pp->Next->Pt) || (pp->Pt == pp->Prev->Pt)
|
|
|| ( SlopesEqual( pp->Prev->Pt, pp->Pt, pp->Next->Pt, m_UseFullRange )
|
|
&& ( !preserveCol
|
|
|| !Pt2IsBetweenPt1AndPt3( pp->Prev->Pt, pp->Pt, pp->Next->Pt ) ) ) )
|
|
{
|
|
lastOK = 0;
|
|
OutPt* tmp = pp;
|
|
pp->Prev->Next = pp->Next;
|
|
pp->Next->Prev = pp->Prev;
|
|
pp = pp->Prev;
|
|
delete tmp;
|
|
}
|
|
else if( pp == lastOK )
|
|
break;
|
|
else
|
|
{
|
|
if( !lastOK )
|
|
lastOK = pp;
|
|
|
|
pp = pp->Next;
|
|
}
|
|
}
|
|
|
|
outrec.Pts = pp;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
int PointCount( OutPt* Pts )
|
|
{
|
|
if( !Pts )
|
|
return 0;
|
|
|
|
int result = 0;
|
|
OutPt* p = Pts;
|
|
|
|
do
|
|
{
|
|
result++;
|
|
p = p->Next;
|
|
} while( p != Pts );
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::BuildResult( Paths& polys )
|
|
{
|
|
polys.reserve( m_PolyOuts.size() );
|
|
|
|
for( PolyOutList::size_type ii = 0; ii < m_PolyOuts.size(); ++ii )
|
|
{
|
|
if( !m_PolyOuts[ii]->Pts )
|
|
continue;
|
|
|
|
Path pg;
|
|
OutPt* p = m_PolyOuts[ii]->Pts->Prev;
|
|
int cnt = PointCount( p );
|
|
|
|
if( cnt < 2 )
|
|
continue;
|
|
|
|
pg.reserve( cnt );
|
|
|
|
for( int jj = 0; jj < cnt; ++jj )
|
|
{
|
|
pg.push_back( p->Pt );
|
|
p = p->Prev;
|
|
}
|
|
|
|
polys.push_back( pg );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::BuildResult2( PolyTree& polytree )
|
|
{
|
|
polytree.Clear();
|
|
polytree.AllNodes.reserve( m_PolyOuts.size() );
|
|
|
|
// add each output polygon/contour to polytree ...
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); i++ )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
int cnt = PointCount( outRec->Pts );
|
|
|
|
if( (outRec->IsOpen && cnt < 2) || (!outRec->IsOpen && cnt < 3) )
|
|
continue;
|
|
|
|
FixHoleLinkage( *outRec );
|
|
PolyNode* pn = new PolyNode();
|
|
// nb: polytree takes ownership of all the PolyNodes
|
|
polytree.AllNodes.push_back( pn );
|
|
outRec->PolyNd = pn;
|
|
pn->Parent = 0;
|
|
pn->Index = 0;
|
|
pn->Contour.reserve( cnt );
|
|
OutPt* op = outRec->Pts->Prev;
|
|
|
|
for( int j = 0; j < cnt; j++ )
|
|
{
|
|
pn->Contour.push_back( op->Pt );
|
|
op = op->Prev;
|
|
}
|
|
}
|
|
|
|
// fixup PolyNode links etc ...
|
|
polytree.Childs.reserve( m_PolyOuts.size() );
|
|
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); i++ )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
|
|
if( !outRec->PolyNd )
|
|
continue;
|
|
|
|
if( outRec->IsOpen )
|
|
{
|
|
outRec->PolyNd->m_IsOpen = true;
|
|
polytree.AddChild( *outRec->PolyNd );
|
|
}
|
|
else if( outRec->FirstLeft && outRec->FirstLeft->PolyNd )
|
|
outRec->FirstLeft->PolyNd->AddChild( *outRec->PolyNd );
|
|
else
|
|
polytree.AddChild( *outRec->PolyNd );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void SwapIntersectNodes( IntersectNode& int1, IntersectNode& int2 )
|
|
{
|
|
// just swap the contents (because fIntersectNodes is a single-linked-list)
|
|
IntersectNode inode = int1; // gets a copy of Int1
|
|
|
|
int1.Edge1 = int2.Edge1;
|
|
int1.Edge2 = int2.Edge2;
|
|
int1.Pt = int2.Pt;
|
|
int2.Edge1 = inode.Edge1;
|
|
int2.Edge2 = inode.Edge2;
|
|
int2.Pt = inode.Pt;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline bool E2InsertsBeforeE1( TEdge& e1, TEdge& e2 )
|
|
{
|
|
if( e2.Curr.X == e1.Curr.X )
|
|
{
|
|
if( e2.Top.Y > e1.Top.Y )
|
|
return e2.Top.X < TopX( e1, e2.Top.Y );
|
|
else
|
|
return e1.Top.X > TopX( e2, e1.Top.Y );
|
|
}
|
|
else
|
|
return e2.Curr.X < e1.Curr.X;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool GetOverlap( const cInt a1, const cInt a2, const cInt b1, const cInt b2,
|
|
cInt& Left, cInt& Right )
|
|
{
|
|
if( a1 < a2 )
|
|
{
|
|
if( b1 < b2 )
|
|
{
|
|
Left = std::max( a1, b1 ); Right = std::min( a2, b2 );
|
|
}
|
|
else
|
|
{
|
|
Left = std::max( a1, b2 ); Right = std::min( a2, b1 );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if( b1 < b2 )
|
|
{
|
|
Left = std::max( a2, b1 ); Right = std::min( a1, b2 );
|
|
}
|
|
else
|
|
{
|
|
Left = std::max( a2, b2 ); Right = std::min( a1, b1 );
|
|
}
|
|
}
|
|
|
|
return Left < Right;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline void UpdateOutPtIdxs( OutRec& outrec )
|
|
{
|
|
OutPt* op = outrec.Pts;
|
|
|
|
do
|
|
{
|
|
op->Idx = outrec.Idx;
|
|
op = op->Prev;
|
|
} while( op != outrec.Pts );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::InsertEdgeIntoAEL( TEdge* edge, TEdge* startEdge )
|
|
{
|
|
if( !m_ActiveEdges )
|
|
{
|
|
edge->PrevInAEL = 0;
|
|
edge->NextInAEL = 0;
|
|
m_ActiveEdges = edge;
|
|
}
|
|
else if( !startEdge && E2InsertsBeforeE1( *m_ActiveEdges, *edge ) )
|
|
{
|
|
edge->PrevInAEL = 0;
|
|
edge->NextInAEL = m_ActiveEdges;
|
|
m_ActiveEdges->PrevInAEL = edge;
|
|
m_ActiveEdges = edge;
|
|
}
|
|
else
|
|
{
|
|
if( !startEdge )
|
|
startEdge = m_ActiveEdges;
|
|
|
|
while( startEdge->NextInAEL
|
|
&& !E2InsertsBeforeE1( *startEdge->NextInAEL, *edge ) )
|
|
startEdge = startEdge->NextInAEL;
|
|
|
|
edge->NextInAEL = startEdge->NextInAEL;
|
|
|
|
if( startEdge->NextInAEL )
|
|
startEdge->NextInAEL->PrevInAEL = edge;
|
|
|
|
edge->PrevInAEL = startEdge;
|
|
startEdge->NextInAEL = edge;
|
|
}
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------
|
|
|
|
OutPt* DupOutPt( OutPt* outPt, bool InsertAfter )
|
|
{
|
|
OutPt* result = new OutPt;
|
|
|
|
result->Pt = outPt->Pt;
|
|
result->Idx = outPt->Idx;
|
|
|
|
if( InsertAfter )
|
|
{
|
|
result->Next = outPt->Next;
|
|
result->Prev = outPt;
|
|
outPt->Next->Prev = result;
|
|
outPt->Next = result;
|
|
}
|
|
else
|
|
{
|
|
result->Prev = outPt->Prev;
|
|
result->Next = outPt;
|
|
outPt->Prev->Next = result;
|
|
outPt->Prev = result;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool JoinHorz( OutPt* op1, OutPt* op1b, OutPt* op2, OutPt* op2b,
|
|
const IntPoint Pt, bool DiscardLeft )
|
|
{
|
|
Direction Dir1 = (op1->Pt.X > op1b->Pt.X ? dRightToLeft : dLeftToRight);
|
|
Direction Dir2 = (op2->Pt.X > op2b->Pt.X ? dRightToLeft : dLeftToRight);
|
|
|
|
if( Dir1 == Dir2 )
|
|
return false;
|
|
|
|
// When DiscardLeft, we want Op1b to be on the Left of Op1, otherwise we
|
|
// want Op1b to be on the Right. (And likewise with Op2 and Op2b.)
|
|
// So, to facilitate this while inserting Op1b and Op2b ...
|
|
// when DiscardLeft, make sure we're AT or RIGHT of Pt before adding Op1b,
|
|
// otherwise make sure we're AT or LEFT of Pt. (Likewise with Op2b.)
|
|
if( Dir1 == dLeftToRight )
|
|
{
|
|
while( op1->Next->Pt.X <= Pt.X
|
|
&& op1->Next->Pt.X >= op1->Pt.X && op1->Next->Pt.Y == Pt.Y )
|
|
op1 = op1->Next;
|
|
|
|
if( DiscardLeft && (op1->Pt.X != Pt.X) )
|
|
op1 = op1->Next;
|
|
|
|
op1b = DupOutPt( op1, !DiscardLeft );
|
|
|
|
if( op1b->Pt != Pt )
|
|
{
|
|
op1 = op1b;
|
|
op1->Pt = Pt;
|
|
op1b = DupOutPt( op1, !DiscardLeft );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
while( op1->Next->Pt.X >= Pt.X
|
|
&& op1->Next->Pt.X <= op1->Pt.X && op1->Next->Pt.Y == Pt.Y )
|
|
op1 = op1->Next;
|
|
|
|
if( !DiscardLeft && (op1->Pt.X != Pt.X) )
|
|
op1 = op1->Next;
|
|
|
|
op1b = DupOutPt( op1, DiscardLeft );
|
|
|
|
if( op1b->Pt != Pt )
|
|
{
|
|
op1 = op1b;
|
|
op1->Pt = Pt;
|
|
op1b = DupOutPt( op1, DiscardLeft );
|
|
}
|
|
}
|
|
|
|
if( Dir2 == dLeftToRight )
|
|
{
|
|
while( op2->Next->Pt.X <= Pt.X
|
|
&& op2->Next->Pt.X >= op2->Pt.X && op2->Next->Pt.Y == Pt.Y )
|
|
op2 = op2->Next;
|
|
|
|
if( DiscardLeft && (op2->Pt.X != Pt.X) )
|
|
op2 = op2->Next;
|
|
|
|
op2b = DupOutPt( op2, !DiscardLeft );
|
|
|
|
if( op2b->Pt != Pt )
|
|
{
|
|
op2 = op2b;
|
|
op2->Pt = Pt;
|
|
op2b = DupOutPt( op2, !DiscardLeft );
|
|
}
|
|
|
|
;
|
|
}
|
|
else
|
|
{
|
|
while( op2->Next->Pt.X >= Pt.X
|
|
&& op2->Next->Pt.X <= op2->Pt.X && op2->Next->Pt.Y == Pt.Y )
|
|
op2 = op2->Next;
|
|
|
|
if( !DiscardLeft && (op2->Pt.X != Pt.X) )
|
|
op2 = op2->Next;
|
|
|
|
op2b = DupOutPt( op2, DiscardLeft );
|
|
|
|
if( op2b->Pt != Pt )
|
|
{
|
|
op2 = op2b;
|
|
op2->Pt = Pt;
|
|
op2b = DupOutPt( op2, DiscardLeft );
|
|
}
|
|
|
|
;
|
|
}
|
|
|
|
;
|
|
|
|
if( (Dir1 == dLeftToRight) == DiscardLeft )
|
|
{
|
|
op1->Prev = op2;
|
|
op2->Next = op1;
|
|
op1b->Next = op2b;
|
|
op2b->Prev = op1b;
|
|
}
|
|
else
|
|
{
|
|
op1->Next = op2;
|
|
op2->Prev = op1;
|
|
op1b->Prev = op2b;
|
|
op2b->Next = op1b;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool Clipper::JoinPoints( Join* j, OutRec* outRec1, OutRec* outRec2 )
|
|
{
|
|
OutPt* op1 = j->OutPt1, * op1b;
|
|
OutPt* op2 = j->OutPt2, * op2b;
|
|
|
|
// There are 3 kinds of joins for output polygons ...
|
|
// 1. Horizontal joins where Join.OutPt1 & Join.OutPt2 are vertices anywhere
|
|
// along (horizontal) collinear edges (& Join.OffPt is on the same horizontal).
|
|
// 2. Non-horizontal joins where Join.OutPt1 & Join.OutPt2 are at the same
|
|
// location at the Bottom of the overlapping segment (& Join.OffPt is above).
|
|
// 3. StrictSimple joins where edges touch but are not collinear and where
|
|
// Join.OutPt1, Join.OutPt2 & Join.OffPt all share the same point.
|
|
bool isHorizontal = (j->OutPt1->Pt.Y == j->OffPt.Y);
|
|
|
|
if( isHorizontal && (j->OffPt == j->OutPt1->Pt)
|
|
&& (j->OffPt == j->OutPt2->Pt) )
|
|
{
|
|
// Strictly Simple join ...
|
|
if( outRec1 != outRec2 )
|
|
return false;
|
|
|
|
op1b = j->OutPt1->Next;
|
|
|
|
while( op1b != op1 && (op1b->Pt == j->OffPt) )
|
|
op1b = op1b->Next;
|
|
|
|
bool reverse1 = (op1b->Pt.Y > j->OffPt.Y);
|
|
op2b = j->OutPt2->Next;
|
|
|
|
while( op2b != op2 && (op2b->Pt == j->OffPt) )
|
|
op2b = op2b->Next;
|
|
|
|
bool reverse2 = (op2b->Pt.Y > j->OffPt.Y);
|
|
|
|
if( reverse1 == reverse2 )
|
|
return false;
|
|
|
|
if( reverse1 )
|
|
{
|
|
op1b = DupOutPt( op1, false );
|
|
op2b = DupOutPt( op2, true );
|
|
op1->Prev = op2;
|
|
op2->Next = op1;
|
|
op1b->Next = op2b;
|
|
op2b->Prev = op1b;
|
|
j->OutPt1 = op1;
|
|
j->OutPt2 = op1b;
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
op1b = DupOutPt( op1, true );
|
|
op2b = DupOutPt( op2, false );
|
|
op1->Next = op2;
|
|
op2->Prev = op1;
|
|
op1b->Prev = op2b;
|
|
op2b->Next = op1b;
|
|
j->OutPt1 = op1;
|
|
j->OutPt2 = op1b;
|
|
return true;
|
|
}
|
|
}
|
|
else if( isHorizontal )
|
|
{
|
|
// treat horizontal joins differently to non-horizontal joins since with
|
|
// them we're not yet sure where the overlapping is. OutPt1.Pt & OutPt2.Pt
|
|
// may be anywhere along the horizontal edge.
|
|
op1b = op1;
|
|
|
|
while( op1->Prev->Pt.Y == op1->Pt.Y && op1->Prev != op1b && op1->Prev != op2 )
|
|
op1 = op1->Prev;
|
|
|
|
while( op1b->Next->Pt.Y == op1b->Pt.Y && op1b->Next != op1 && op1b->Next != op2 )
|
|
op1b = op1b->Next;
|
|
|
|
if( op1b->Next == op1 || op1b->Next == op2 )
|
|
return false; // a flat 'polygon'
|
|
|
|
op2b = op2;
|
|
|
|
while( op2->Prev->Pt.Y == op2->Pt.Y && op2->Prev != op2b && op2->Prev != op1b )
|
|
op2 = op2->Prev;
|
|
|
|
while( op2b->Next->Pt.Y == op2b->Pt.Y && op2b->Next != op2 && op2b->Next != op1 )
|
|
op2b = op2b->Next;
|
|
|
|
if( op2b->Next == op2 || op2b->Next == op1 )
|
|
return false; // a flat 'polygon'
|
|
|
|
cInt Left, Right;
|
|
|
|
// Op1 --> Op1b & Op2 --> Op2b are the extremites of the horizontal edges
|
|
if( !GetOverlap( op1->Pt.X, op1b->Pt.X, op2->Pt.X, op2b->Pt.X, Left, Right ) )
|
|
return false;
|
|
|
|
// DiscardLeftSide: when overlapping edges are joined, a spike will created
|
|
// which needs to be cleaned up. However, we don't want Op1 or Op2 caught up
|
|
// on the discard Side as either may still be needed for other joins ...
|
|
IntPoint Pt;
|
|
bool DiscardLeftSide;
|
|
|
|
if( op1->Pt.X >= Left && op1->Pt.X <= Right )
|
|
{
|
|
Pt = op1->Pt; DiscardLeftSide = (op1->Pt.X > op1b->Pt.X);
|
|
}
|
|
else if( op2->Pt.X >= Left&& op2->Pt.X <= Right )
|
|
{
|
|
Pt = op2->Pt; DiscardLeftSide = (op2->Pt.X > op2b->Pt.X);
|
|
}
|
|
else if( op1b->Pt.X >= Left && op1b->Pt.X <= Right )
|
|
{
|
|
Pt = op1b->Pt; DiscardLeftSide = op1b->Pt.X > op1->Pt.X;
|
|
}
|
|
else
|
|
{
|
|
Pt = op2b->Pt; DiscardLeftSide = (op2b->Pt.X > op2->Pt.X);
|
|
}
|
|
|
|
j->OutPt1 = op1; j->OutPt2 = op2;
|
|
return JoinHorz( op1, op1b, op2, op2b, Pt, DiscardLeftSide );
|
|
}
|
|
else
|
|
{
|
|
// nb: For non-horizontal joins ...
|
|
// 1. Jr.OutPt1.Pt.Y == Jr.OutPt2.Pt.Y
|
|
// 2. Jr.OutPt1.Pt > Jr.OffPt.Y
|
|
|
|
// make sure the polygons are correctly oriented ...
|
|
op1b = op1->Next;
|
|
|
|
while( (op1b->Pt == op1->Pt) && (op1b != op1) )
|
|
op1b = op1b->Next;
|
|
|
|
bool Reverse1 = ( (op1b->Pt.Y > op1->Pt.Y)
|
|
|| !SlopesEqual( op1->Pt, op1b->Pt, j->OffPt, m_UseFullRange ) );
|
|
|
|
if( Reverse1 )
|
|
{
|
|
op1b = op1->Prev;
|
|
|
|
while( (op1b->Pt == op1->Pt) && (op1b != op1) )
|
|
op1b = op1b->Prev;
|
|
|
|
if( (op1b->Pt.Y > op1->Pt.Y)
|
|
|| !SlopesEqual( op1->Pt, op1b->Pt, j->OffPt, m_UseFullRange ) )
|
|
return false;
|
|
}
|
|
|
|
;
|
|
op2b = op2->Next;
|
|
|
|
while( (op2b->Pt == op2->Pt) && (op2b != op2) )
|
|
op2b = op2b->Next;
|
|
|
|
bool Reverse2 = ( (op2b->Pt.Y > op2->Pt.Y)
|
|
|| !SlopesEqual( op2->Pt, op2b->Pt, j->OffPt, m_UseFullRange ) );
|
|
|
|
if( Reverse2 )
|
|
{
|
|
op2b = op2->Prev;
|
|
|
|
while( (op2b->Pt == op2->Pt) && (op2b != op2) )
|
|
op2b = op2b->Prev;
|
|
|
|
if( (op2b->Pt.Y > op2->Pt.Y)
|
|
|| !SlopesEqual( op2->Pt, op2b->Pt, j->OffPt, m_UseFullRange ) )
|
|
return false;
|
|
}
|
|
|
|
if( (op1b == op1) || (op2b == op2) || (op1b == op2b)
|
|
|| ( (outRec1 == outRec2) && (Reverse1 == Reverse2) ) )
|
|
return false;
|
|
|
|
if( Reverse1 )
|
|
{
|
|
op1b = DupOutPt( op1, false );
|
|
op2b = DupOutPt( op2, true );
|
|
op1->Prev = op2;
|
|
op2->Next = op1;
|
|
op1b->Next = op2b;
|
|
op2b->Prev = op1b;
|
|
j->OutPt1 = op1;
|
|
j->OutPt2 = op1b;
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
op1b = DupOutPt( op1, true );
|
|
op2b = DupOutPt( op2, false );
|
|
op1->Next = op2;
|
|
op2->Prev = op1;
|
|
op1b->Prev = op2b;
|
|
op2b->Next = op1b;
|
|
j->OutPt1 = op1;
|
|
j->OutPt2 = op1b;
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------
|
|
|
|
static OutRec* ParseFirstLeft( OutRec* FirstLeft )
|
|
{
|
|
while( FirstLeft && !FirstLeft->Pts )
|
|
FirstLeft = FirstLeft->FirstLeft;
|
|
|
|
return FirstLeft;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::FixupFirstLefts1( OutRec* OldOutRec, OutRec* NewOutRec )
|
|
{
|
|
// tests if NewOutRec contains the polygon before reassigning FirstLeft
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
OutRec* firstLeft = ParseFirstLeft( outRec->FirstLeft );
|
|
|
|
if( outRec->Pts && firstLeft == OldOutRec )
|
|
{
|
|
if( Poly2ContainsPoly1( outRec->Pts, NewOutRec->Pts ) )
|
|
outRec->FirstLeft = NewOutRec;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------
|
|
|
|
void Clipper::FixupFirstLefts2( OutRec* InnerOutRec, OutRec* OuterOutRec )
|
|
{
|
|
// A polygon has split into two such that one is now the inner of the other.
|
|
// It's possible that these polygons now wrap around other polygons, so check
|
|
// every polygon that's also contained by OuterOutRec's FirstLeft container
|
|
// (including 0) to see if they've become inner to the new inner polygon ...
|
|
OutRec* orfl = OuterOutRec->FirstLeft;
|
|
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
|
|
if( !outRec->Pts || outRec == OuterOutRec || outRec == InnerOutRec )
|
|
continue;
|
|
|
|
OutRec* firstLeft = ParseFirstLeft( outRec->FirstLeft );
|
|
|
|
if( firstLeft != orfl && firstLeft != InnerOutRec && firstLeft != OuterOutRec )
|
|
continue;
|
|
|
|
if( Poly2ContainsPoly1( outRec->Pts, InnerOutRec->Pts ) )
|
|
outRec->FirstLeft = InnerOutRec;
|
|
else if( Poly2ContainsPoly1( outRec->Pts, OuterOutRec->Pts ) )
|
|
outRec->FirstLeft = OuterOutRec;
|
|
else if( outRec->FirstLeft == InnerOutRec || outRec->FirstLeft == OuterOutRec )
|
|
outRec->FirstLeft = orfl;
|
|
}
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------
|
|
void Clipper::FixupFirstLefts3( OutRec* OldOutRec, OutRec* NewOutRec )
|
|
{
|
|
// reassigns FirstLeft WITHOUT testing if NewOutRec contains the polygon
|
|
for( PolyOutList::size_type i = 0; i < m_PolyOuts.size(); ++i )
|
|
{
|
|
OutRec* outRec = m_PolyOuts[i];
|
|
OutRec* firstLeft = ParseFirstLeft( outRec->FirstLeft );
|
|
|
|
if( outRec->Pts && firstLeft == OldOutRec )
|
|
outRec->FirstLeft = NewOutRec;
|
|
}
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------
|
|
|
|
void Clipper::JoinCommonEdges()
|
|
{
|
|
for( JoinList::size_type i = 0; i < m_Joins.size(); i++ )
|
|
{
|
|
Join* join = m_Joins[i];
|
|
|
|
OutRec* outRec1 = GetOutRec( join->OutPt1->Idx );
|
|
OutRec* outRec2 = GetOutRec( join->OutPt2->Idx );
|
|
|
|
if( !outRec1->Pts || !outRec2->Pts )
|
|
continue;
|
|
|
|
if( outRec1->IsOpen || outRec2->IsOpen )
|
|
continue;
|
|
|
|
// get the polygon fragment with the correct hole state (FirstLeft)
|
|
// before calling JoinPoints() ...
|
|
OutRec* holeStateRec;
|
|
|
|
if( outRec1 == outRec2 )
|
|
holeStateRec = outRec1;
|
|
else if( OutRec1RightOfOutRec2( outRec1, outRec2 ) )
|
|
holeStateRec = outRec2;
|
|
else if( OutRec1RightOfOutRec2( outRec2, outRec1 ) )
|
|
holeStateRec = outRec1;
|
|
else
|
|
holeStateRec = GetLowermostRec( outRec1, outRec2 );
|
|
|
|
if( !JoinPoints( join, outRec1, outRec2 ) )
|
|
continue;
|
|
|
|
if( outRec1 == outRec2 )
|
|
{
|
|
// instead of joining two polygons, we've just created a new one by
|
|
// splitting one polygon into two.
|
|
outRec1->Pts = join->OutPt1;
|
|
outRec1->BottomPt = 0;
|
|
outRec2 = CreateOutRec();
|
|
outRec2->Pts = join->OutPt2;
|
|
|
|
// update all OutRec2.Pts Idx's ...
|
|
UpdateOutPtIdxs( *outRec2 );
|
|
|
|
if( Poly2ContainsPoly1( outRec2->Pts, outRec1->Pts ) )
|
|
{
|
|
// outRec1 contains outRec2 ...
|
|
outRec2->IsHole = !outRec1->IsHole;
|
|
outRec2->FirstLeft = outRec1;
|
|
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts2( outRec2, outRec1 );
|
|
|
|
if( (outRec2->IsHole ^ m_ReverseOutput) == (Area( *outRec2 ) > 0) )
|
|
ReversePolyPtLinks( outRec2->Pts );
|
|
}
|
|
else if( Poly2ContainsPoly1( outRec1->Pts, outRec2->Pts ) )
|
|
{
|
|
// outRec2 contains outRec1 ...
|
|
outRec2->IsHole = outRec1->IsHole;
|
|
outRec1->IsHole = !outRec2->IsHole;
|
|
outRec2->FirstLeft = outRec1->FirstLeft;
|
|
outRec1->FirstLeft = outRec2;
|
|
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts2( outRec1, outRec2 );
|
|
|
|
if( (outRec1->IsHole ^ m_ReverseOutput) == (Area( *outRec1 ) > 0) )
|
|
ReversePolyPtLinks( outRec1->Pts );
|
|
}
|
|
else
|
|
{
|
|
// the 2 polygons are completely separate ...
|
|
outRec2->IsHole = outRec1->IsHole;
|
|
outRec2->FirstLeft = outRec1->FirstLeft;
|
|
|
|
// fixup FirstLeft pointers that may need reassigning to OutRec2
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts1( outRec1, outRec2 );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// joined 2 polygons together ...
|
|
|
|
outRec2->Pts = 0;
|
|
outRec2->BottomPt = 0;
|
|
outRec2->Idx = outRec1->Idx;
|
|
|
|
outRec1->IsHole = holeStateRec->IsHole;
|
|
|
|
if( holeStateRec == outRec2 )
|
|
outRec1->FirstLeft = outRec2->FirstLeft;
|
|
|
|
outRec2->FirstLeft = outRec1;
|
|
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts3( outRec2, outRec1 );
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
// ClipperOffset support functions ...
|
|
// ------------------------------------------------------------------------------
|
|
|
|
DoublePoint GetUnitNormal( const IntPoint& pt1, const IntPoint& pt2 )
|
|
{
|
|
if( pt2.X == pt1.X && pt2.Y == pt1.Y )
|
|
return DoublePoint( 0, 0 );
|
|
|
|
double Dx = (double) (pt2.X - pt1.X);
|
|
double dy = (double) (pt2.Y - pt1.Y);
|
|
double f = 1 * 1.0 / std::sqrt( Dx * Dx + dy * dy );
|
|
Dx *= f;
|
|
dy *= f;
|
|
return DoublePoint( dy, -Dx );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
// ClipperOffset class
|
|
// ------------------------------------------------------------------------------
|
|
|
|
ClipperOffset::ClipperOffset( double miterLimit, double arcTolerance )
|
|
{
|
|
this->MiterLimit = miterLimit;
|
|
this->ArcTolerance = arcTolerance;
|
|
m_lowest.X = -1;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
ClipperOffset::~ClipperOffset()
|
|
{
|
|
Clear();
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::Clear()
|
|
{
|
|
for( int i = 0; i < m_polyNodes.ChildCount(); ++i )
|
|
delete m_polyNodes.Childs[i];
|
|
|
|
m_polyNodes.Childs.clear();
|
|
m_lowest.X = -1;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::AddPath( const Path& path, JoinType joinType, EndType endType )
|
|
{
|
|
int highI = (int) path.size() - 1;
|
|
|
|
if( highI < 0 )
|
|
return;
|
|
|
|
PolyNode* newNode = new PolyNode();
|
|
newNode->m_jointype = joinType;
|
|
newNode->m_endtype = endType;
|
|
|
|
// strip duplicate points from path and also get index to the lowest point ...
|
|
if( endType == etClosedLine || endType == etClosedPolygon )
|
|
while( highI > 0 && path[0] == path[highI] )
|
|
highI--;
|
|
|
|
|
|
newNode->Contour.reserve( highI + 1 );
|
|
newNode->Contour.push_back( path[0] );
|
|
int j = 0, k = 0;
|
|
|
|
for( int i = 1; i <= highI; i++ )
|
|
if( newNode->Contour[j] != path[i] )
|
|
{
|
|
j++;
|
|
newNode->Contour.push_back( path[i] );
|
|
|
|
if( path[i].Y > newNode->Contour[k].Y
|
|
|| (path[i].Y == newNode->Contour[k].Y
|
|
&& path[i].X < newNode->Contour[k].X) )
|
|
k = j;
|
|
}
|
|
|
|
|
|
if( endType == etClosedPolygon && j < 2 )
|
|
{
|
|
delete newNode;
|
|
return;
|
|
}
|
|
|
|
m_polyNodes.AddChild( *newNode );
|
|
|
|
// if this path's lowest pt is lower than all the others then update m_lowest
|
|
if( endType != etClosedPolygon )
|
|
return;
|
|
|
|
if( m_lowest.X < 0 )
|
|
m_lowest = IntPoint( m_polyNodes.ChildCount() - 1, k );
|
|
else
|
|
{
|
|
IntPoint ip = m_polyNodes.Childs[(int) m_lowest.X]->Contour[(int) m_lowest.Y];
|
|
|
|
if( newNode->Contour[k].Y > ip.Y
|
|
|| (newNode->Contour[k].Y == ip.Y
|
|
&& newNode->Contour[k].X < ip.X) )
|
|
m_lowest = IntPoint( m_polyNodes.ChildCount() - 1, k );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::AddPaths( const Paths& paths, JoinType joinType, EndType endType )
|
|
{
|
|
for( Paths::size_type i = 0; i < paths.size(); ++i )
|
|
AddPath( paths[i], joinType, endType );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::FixOrientations()
|
|
{
|
|
// fixup orientations of all closed paths if the orientation of the
|
|
// closed path with the lowermost vertex is wrong ...
|
|
if( m_lowest.X >= 0
|
|
&& !Orientation( m_polyNodes.Childs[(int) m_lowest.X]->Contour ) )
|
|
{
|
|
for( int i = 0; i < m_polyNodes.ChildCount(); ++i )
|
|
{
|
|
PolyNode& node = *m_polyNodes.Childs[i];
|
|
|
|
if( node.m_endtype == etClosedPolygon
|
|
|| ( node.m_endtype == etClosedLine && Orientation( node.Contour ) ) )
|
|
ReversePath( node.Contour );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for( int i = 0; i < m_polyNodes.ChildCount(); ++i )
|
|
{
|
|
PolyNode& node = *m_polyNodes.Childs[i];
|
|
|
|
if( node.m_endtype == etClosedLine && !Orientation( node.Contour ) )
|
|
ReversePath( node.Contour );
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::Execute( Paths& solution, double delta )
|
|
{
|
|
solution.clear();
|
|
FixOrientations();
|
|
DoOffset( delta );
|
|
|
|
// now clean up 'corners' ...
|
|
Clipper clpr;
|
|
clpr.AddPaths( m_destPolys, ptSubject, true );
|
|
|
|
if( delta > 0 )
|
|
{
|
|
clpr.Execute( ctUnion, solution, pftPositive, pftPositive );
|
|
}
|
|
else
|
|
{
|
|
IntRect r = clpr.GetBounds();
|
|
Path outer( 4 );
|
|
outer[0] = IntPoint( r.left - 10, r.bottom + 10 );
|
|
outer[1] = IntPoint( r.right + 10, r.bottom + 10 );
|
|
outer[2] = IntPoint( r.right + 10, r.top - 10 );
|
|
outer[3] = IntPoint( r.left - 10, r.top - 10 );
|
|
|
|
clpr.AddPath( outer, ptSubject, true );
|
|
clpr.ReverseSolution( true );
|
|
clpr.Execute( ctUnion, solution, pftNegative, pftNegative );
|
|
|
|
if( solution.size() > 0 )
|
|
solution.erase( solution.begin() );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::Execute( PolyTree& solution, double delta )
|
|
{
|
|
solution.Clear();
|
|
FixOrientations();
|
|
DoOffset( delta );
|
|
|
|
// now clean up 'corners' ...
|
|
Clipper clpr;
|
|
clpr.AddPaths( m_destPolys, ptSubject, true );
|
|
|
|
if( delta > 0 )
|
|
{
|
|
clpr.Execute( ctUnion, solution, pftPositive, pftPositive );
|
|
}
|
|
else
|
|
{
|
|
IntRect r = clpr.GetBounds();
|
|
Path outer( 4 );
|
|
outer[0] = IntPoint( r.left - 10, r.bottom + 10 );
|
|
outer[1] = IntPoint( r.right + 10, r.bottom + 10 );
|
|
outer[2] = IntPoint( r.right + 10, r.top - 10 );
|
|
outer[3] = IntPoint( r.left - 10, r.top - 10 );
|
|
|
|
clpr.AddPath( outer, ptSubject, true );
|
|
clpr.ReverseSolution( true );
|
|
clpr.Execute( ctUnion, solution, pftNegative, pftNegative );
|
|
|
|
// remove the outer PolyNode rectangle ...
|
|
if( solution.ChildCount() == 1 && solution.Childs[0]->ChildCount() > 0 )
|
|
{
|
|
PolyNode* outerNode = solution.Childs[0];
|
|
solution.Childs.reserve( outerNode->ChildCount() );
|
|
solution.Childs[0] = outerNode->Childs[0];
|
|
solution.Childs[0]->Parent = outerNode->Parent;
|
|
|
|
for( int i = 1; i < outerNode->ChildCount(); ++i )
|
|
solution.AddChild( *outerNode->Childs[i] );
|
|
}
|
|
else
|
|
solution.Clear();
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::DoOffset( double delta )
|
|
{
|
|
m_destPolys.clear();
|
|
m_delta = delta;
|
|
|
|
// if Zero offset, just copy any CLOSED polygons to m_p and return ...
|
|
if( NEAR_ZERO( delta ) )
|
|
{
|
|
m_destPolys.reserve( m_polyNodes.ChildCount() );
|
|
|
|
for( int i = 0; i < m_polyNodes.ChildCount(); i++ )
|
|
{
|
|
PolyNode& node = *m_polyNodes.Childs[i];
|
|
|
|
if( node.m_endtype == etClosedPolygon )
|
|
m_destPolys.push_back( node.Contour );
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
// see offset_triginometry3.svg in the documentation folder ...
|
|
if( MiterLimit > 2 )
|
|
m_miterLim = 2 / (MiterLimit * MiterLimit);
|
|
else
|
|
m_miterLim = 0.5;
|
|
|
|
double y;
|
|
|
|
if( ArcTolerance <= 0.0 )
|
|
y = def_arc_tolerance;
|
|
else if( ArcTolerance > std::fabs( delta ) * def_arc_tolerance )
|
|
y = std::fabs( delta ) * def_arc_tolerance;
|
|
else
|
|
y = ArcTolerance;
|
|
|
|
// see offset_triginometry2.svg in the documentation folder ...
|
|
double steps = pi / std::acos( 1 - y / std::fabs( delta ) );
|
|
|
|
if( steps > std::fabs( delta ) * pi )
|
|
steps = std::fabs( delta ) * pi; // ie excessive precision check
|
|
|
|
m_sin = std::sin( two_pi / steps );
|
|
m_cos = std::cos( two_pi / steps );
|
|
m_StepsPerRad = steps / two_pi;
|
|
|
|
if( delta < 0.0 )
|
|
m_sin = -m_sin;
|
|
|
|
m_destPolys.reserve( m_polyNodes.ChildCount() * 2 );
|
|
|
|
for( int i = 0; i < m_polyNodes.ChildCount(); i++ )
|
|
{
|
|
PolyNode& node = *m_polyNodes.Childs[i];
|
|
m_srcPoly = node.Contour;
|
|
|
|
int len = (int) m_srcPoly.size();
|
|
|
|
if( len == 0 || ( delta <= 0 && (len < 3 || node.m_endtype != etClosedPolygon) ) )
|
|
continue;
|
|
|
|
m_destPoly.clear();
|
|
|
|
if( len == 1 )
|
|
{
|
|
if( node.m_jointype == jtRound )
|
|
{
|
|
double X = 1.0, Y = 0.0;
|
|
|
|
for( cInt j = 1; j <= steps; j++ )
|
|
{
|
|
m_destPoly.push_back( IntPoint(
|
|
Round( m_srcPoly[0].X + X * delta ),
|
|
Round( m_srcPoly[0].Y + Y * delta ) ) );
|
|
double X2 = X;
|
|
X = X * m_cos - m_sin * Y;
|
|
Y = X2 * m_sin + Y * m_cos;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
double X = -1.0, Y = -1.0;
|
|
|
|
for( int j = 0; j < 4; ++j )
|
|
{
|
|
m_destPoly.push_back( IntPoint(
|
|
Round( m_srcPoly[0].X + X * delta ),
|
|
Round( m_srcPoly[0].Y + Y * delta ) ) );
|
|
|
|
if( X < 0 )
|
|
X = 1;
|
|
else if( Y < 0 )
|
|
Y = 1;
|
|
else
|
|
X = -1;
|
|
}
|
|
}
|
|
|
|
m_destPolys.push_back( m_destPoly );
|
|
continue;
|
|
}
|
|
|
|
// build m_normals ...
|
|
m_normals.clear();
|
|
m_normals.reserve( len );
|
|
|
|
for( int j = 0; j < len - 1; ++j )
|
|
m_normals.push_back( GetUnitNormal( m_srcPoly[j], m_srcPoly[j + 1] ) );
|
|
|
|
if( node.m_endtype == etClosedLine || node.m_endtype == etClosedPolygon )
|
|
m_normals.push_back( GetUnitNormal( m_srcPoly[len - 1], m_srcPoly[0] ) );
|
|
else
|
|
m_normals.push_back( DoublePoint( m_normals[len - 2] ) );
|
|
|
|
if( node.m_endtype == etClosedPolygon )
|
|
{
|
|
int k = len - 1;
|
|
|
|
for( int j = 0; j < len; ++j )
|
|
OffsetPoint( j, k, node.m_jointype );
|
|
|
|
m_destPolys.push_back( m_destPoly );
|
|
}
|
|
else if( node.m_endtype == etClosedLine )
|
|
{
|
|
int k = len - 1;
|
|
|
|
for( int j = 0; j < len; ++j )
|
|
OffsetPoint( j, k, node.m_jointype );
|
|
|
|
m_destPolys.push_back( m_destPoly );
|
|
m_destPoly.clear();
|
|
// re-build m_normals ...
|
|
DoublePoint n = m_normals[len - 1];
|
|
|
|
for( int j = len - 1; j > 0; j-- )
|
|
m_normals[j] = DoublePoint( -m_normals[j - 1].X, -m_normals[j - 1].Y );
|
|
|
|
m_normals[0] = DoublePoint( -n.X, -n.Y );
|
|
k = 0;
|
|
|
|
for( int j = len - 1; j >= 0; j-- )
|
|
OffsetPoint( j, k, node.m_jointype );
|
|
|
|
m_destPolys.push_back( m_destPoly );
|
|
}
|
|
else
|
|
{
|
|
int k = 0;
|
|
|
|
for( int j = 1; j < len - 1; ++j )
|
|
OffsetPoint( j, k, node.m_jointype );
|
|
|
|
IntPoint pt1;
|
|
|
|
if( node.m_endtype == etOpenButt )
|
|
{
|
|
int j = len - 1;
|
|
pt1 = IntPoint( (cInt) Round( m_srcPoly[j].X + m_normals[j].X *
|
|
delta ), (cInt) Round( m_srcPoly[j].Y + m_normals[j].Y * delta ) );
|
|
m_destPoly.push_back( pt1 );
|
|
pt1 = IntPoint( (cInt) Round( m_srcPoly[j].X - m_normals[j].X *
|
|
delta ), (cInt) Round( m_srcPoly[j].Y - m_normals[j].Y * delta ) );
|
|
m_destPoly.push_back( pt1 );
|
|
}
|
|
else
|
|
{
|
|
int j = len - 1;
|
|
k = len - 2;
|
|
m_sinA = 0;
|
|
m_normals[j] = DoublePoint( -m_normals[j].X, -m_normals[j].Y );
|
|
|
|
if( node.m_endtype == etOpenSquare )
|
|
DoSquare( j, k );
|
|
else
|
|
DoRound( j, k );
|
|
}
|
|
|
|
// re-build m_normals ...
|
|
for( int j = len - 1; j > 0; j-- )
|
|
m_normals[j] = DoublePoint( -m_normals[j - 1].X, -m_normals[j - 1].Y );
|
|
|
|
m_normals[0] = DoublePoint( -m_normals[1].X, -m_normals[1].Y );
|
|
|
|
k = len - 1;
|
|
|
|
for( int j = k - 1; j > 0; --j )
|
|
OffsetPoint( j, k, node.m_jointype );
|
|
|
|
if( node.m_endtype == etOpenButt )
|
|
{
|
|
pt1 = IntPoint( (cInt) Round( m_srcPoly[0].X - m_normals[0].X * delta ),
|
|
(cInt) Round( m_srcPoly[0].Y - m_normals[0].Y * delta ) );
|
|
m_destPoly.push_back( pt1 );
|
|
pt1 = IntPoint( (cInt) Round( m_srcPoly[0].X + m_normals[0].X * delta ),
|
|
(cInt) Round( m_srcPoly[0].Y + m_normals[0].Y * delta ) );
|
|
m_destPoly.push_back( pt1 );
|
|
}
|
|
else
|
|
{
|
|
k = 1;
|
|
m_sinA = 0;
|
|
|
|
if( node.m_endtype == etOpenSquare )
|
|
DoSquare( 0, 1 );
|
|
else
|
|
DoRound( 0, 1 );
|
|
}
|
|
|
|
m_destPolys.push_back( m_destPoly );
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::OffsetPoint( int j, int& k, JoinType jointype )
|
|
{
|
|
// cross product ...
|
|
m_sinA = (m_normals[k].X * m_normals[j].Y - m_normals[j].X * m_normals[k].Y);
|
|
|
|
if( std::fabs( m_sinA * m_delta ) < 1.0 )
|
|
{
|
|
// dot product ...
|
|
double cosA = (m_normals[k].X * m_normals[j].X + m_normals[j].Y * m_normals[k].Y );
|
|
|
|
if( cosA > 0 ) // angle => 0 degrees
|
|
{
|
|
m_destPoly.push_back( IntPoint( Round( m_srcPoly[j].X + m_normals[k].X * m_delta ),
|
|
Round( m_srcPoly[j].Y + m_normals[k].Y * m_delta ) ) );
|
|
return;
|
|
}
|
|
|
|
// else angle => 180 degrees
|
|
}
|
|
else if( m_sinA > 1.0 )
|
|
m_sinA = 1.0;
|
|
else if( m_sinA < -1.0 )
|
|
m_sinA = -1.0;
|
|
|
|
if( m_sinA * m_delta < 0 )
|
|
{
|
|
m_destPoly.push_back( IntPoint( Round( m_srcPoly[j].X + m_normals[k].X * m_delta ),
|
|
Round( m_srcPoly[j].Y + m_normals[k].Y * m_delta ) ) );
|
|
m_destPoly.push_back( m_srcPoly[j] );
|
|
m_destPoly.push_back( IntPoint( Round( m_srcPoly[j].X + m_normals[j].X * m_delta ),
|
|
Round( m_srcPoly[j].Y + m_normals[j].Y * m_delta ) ) );
|
|
}
|
|
else
|
|
switch( jointype )
|
|
{
|
|
case jtMiter:
|
|
{
|
|
double r = 1 + (m_normals[j].X * m_normals[k].X +
|
|
m_normals[j].Y * m_normals[k].Y);
|
|
|
|
if( r >= m_miterLim )
|
|
DoMiter( j, k, r );
|
|
else
|
|
DoSquare( j, k );
|
|
|
|
break;
|
|
}
|
|
|
|
case jtSquare:
|
|
DoSquare( j, k ); break;
|
|
|
|
case jtRound:
|
|
DoRound( j, k ); break;
|
|
}
|
|
|
|
|
|
k = j;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::DoSquare( int j, int k )
|
|
{
|
|
double dx = std::tan( std::atan2( m_sinA,
|
|
m_normals[k].X * m_normals[j].X + m_normals[k].Y * m_normals[j].Y ) / 4 );
|
|
|
|
m_destPoly.push_back( IntPoint(
|
|
Round( m_srcPoly[j].X + m_delta * (m_normals[k].X - m_normals[k].Y * dx) ),
|
|
Round( m_srcPoly[j].Y + m_delta * (m_normals[k].Y + m_normals[k].X * dx) ) ) );
|
|
m_destPoly.push_back( IntPoint(
|
|
Round( m_srcPoly[j].X + m_delta * (m_normals[j].X + m_normals[j].Y * dx) ),
|
|
Round( m_srcPoly[j].Y + m_delta * (m_normals[j].Y - m_normals[j].X * dx) ) ) );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::DoMiter( int j, int k, double r )
|
|
{
|
|
double q = m_delta / r;
|
|
|
|
m_destPoly.push_back( IntPoint( Round( m_srcPoly[j].X + (m_normals[k].X + m_normals[j].X) * q ),
|
|
Round( m_srcPoly[j].Y + (m_normals[k].Y + m_normals[j].Y) * q ) ) );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClipperOffset::DoRound( int j, int k )
|
|
{
|
|
double a = std::atan2( m_sinA,
|
|
m_normals[k].X * m_normals[j].X + m_normals[k].Y * m_normals[j].Y );
|
|
int steps = std::max( (int) Round( m_StepsPerRad * std::fabs( a ) ), 1 );
|
|
|
|
double X = m_normals[k].X, Y = m_normals[k].Y, X2;
|
|
|
|
for( int i = 0; i < steps; ++i )
|
|
{
|
|
m_destPoly.push_back( IntPoint(
|
|
Round( m_srcPoly[j].X + X * m_delta ),
|
|
Round( m_srcPoly[j].Y + Y * m_delta ) ) );
|
|
X2 = X;
|
|
X = X * m_cos - m_sin * Y;
|
|
Y = X2 * m_sin + Y * m_cos;
|
|
}
|
|
|
|
m_destPoly.push_back( IntPoint(
|
|
Round( m_srcPoly[j].X + m_normals[j].X * m_delta ),
|
|
Round( m_srcPoly[j].Y + m_normals[j].Y * m_delta ) ) );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
// Miscellaneous public functions
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Clipper::DoSimplePolygons()
|
|
{
|
|
PolyOutList::size_type i = 0;
|
|
|
|
while( i < m_PolyOuts.size() )
|
|
{
|
|
OutRec* outrec = m_PolyOuts[i++];
|
|
OutPt* op = outrec->Pts;
|
|
|
|
if( !op || outrec->IsOpen )
|
|
continue;
|
|
|
|
do // for each Pt in Polygon until duplicate found do ...
|
|
{
|
|
OutPt* op2 = op->Next;
|
|
|
|
while( op2 != outrec->Pts )
|
|
{
|
|
if( (op->Pt == op2->Pt) && op2->Next != op && op2->Prev != op )
|
|
{
|
|
// split the polygon into two ...
|
|
OutPt* op3 = op->Prev;
|
|
OutPt* op4 = op2->Prev;
|
|
op->Prev = op4;
|
|
op4->Next = op;
|
|
op2->Prev = op3;
|
|
op3->Next = op2;
|
|
|
|
outrec->Pts = op;
|
|
OutRec* outrec2 = CreateOutRec();
|
|
outrec2->Pts = op2;
|
|
UpdateOutPtIdxs( *outrec2 );
|
|
|
|
if( Poly2ContainsPoly1( outrec2->Pts, outrec->Pts ) )
|
|
{
|
|
// OutRec2 is contained by OutRec1 ...
|
|
outrec2->IsHole = !outrec->IsHole;
|
|
outrec2->FirstLeft = outrec;
|
|
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts2( outrec2, outrec );
|
|
}
|
|
else
|
|
if( Poly2ContainsPoly1( outrec->Pts, outrec2->Pts ) )
|
|
{
|
|
// OutRec1 is contained by OutRec2 ...
|
|
outrec2->IsHole = outrec->IsHole;
|
|
outrec->IsHole = !outrec2->IsHole;
|
|
outrec2->FirstLeft = outrec->FirstLeft;
|
|
outrec->FirstLeft = outrec2;
|
|
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts2( outrec, outrec2 );
|
|
}
|
|
else
|
|
{
|
|
// the 2 polygons are separate ...
|
|
outrec2->IsHole = outrec->IsHole;
|
|
outrec2->FirstLeft = outrec->FirstLeft;
|
|
|
|
if( m_UsingPolyTree )
|
|
FixupFirstLefts1( outrec, outrec2 );
|
|
}
|
|
|
|
|
|
op2 = op; // ie get ready for the Next iteration
|
|
}
|
|
|
|
op2 = op2->Next;
|
|
}
|
|
|
|
op = op->Next;
|
|
} while( op != outrec->Pts );
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ReversePath( Path& p )
|
|
{
|
|
std::reverse( p.begin(), p.end() );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ReversePaths( Paths& p )
|
|
{
|
|
for( Paths::size_type i = 0; i < p.size(); ++i )
|
|
ReversePath( p[i] );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void SimplifyPolygon( const Path& in_poly, Paths& out_polys, PolyFillType fillType )
|
|
{
|
|
Clipper c;
|
|
|
|
c.StrictlySimple( true );
|
|
c.AddPath( in_poly, ptSubject, true );
|
|
c.Execute( ctUnion, out_polys, fillType, fillType );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void SimplifyPolygons( const Paths& in_polys, Paths& out_polys, PolyFillType fillType )
|
|
{
|
|
Clipper c;
|
|
|
|
c.StrictlySimple( true );
|
|
c.AddPaths( in_polys, ptSubject, true );
|
|
c.Execute( ctUnion, out_polys, fillType, fillType );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void SimplifyPolygons( Paths& polys, PolyFillType fillType )
|
|
{
|
|
SimplifyPolygons( polys, polys, fillType );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
inline double DistanceSqrd( const IntPoint& pt1, const IntPoint& pt2 )
|
|
{
|
|
double Dx = ( (double) pt1.X - pt2.X );
|
|
double dy = ( (double) pt1.Y - pt2.Y );
|
|
|
|
return Dx * Dx + dy * dy;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
double DistanceFromLineSqrd( const IntPoint& pt, const IntPoint& ln1, const IntPoint& ln2 )
|
|
{
|
|
// The equation of a line in general form (Ax + By + C = 0)
|
|
// given 2 points (x¹,y¹) & (x²,y²) is ...
|
|
// (y¹ - y²)x + (x² - x¹)y + (y² - y¹)x¹ - (x² - x¹)y¹ = 0
|
|
// A = (y¹ - y²); B = (x² - x¹); C = (y² - y¹)x¹ - (x² - x¹)y¹
|
|
// perpendicular distance of point (x³,y³) = (Ax³ + By³ + C)/Sqrt(A² + B²)
|
|
// see http://en.wikipedia.org/wiki/Perpendicular_distance
|
|
double A = double(ln1.Y - ln2.Y);
|
|
double B = double(ln2.X - ln1.X);
|
|
double C = A * ln1.X + B * ln1.Y;
|
|
|
|
C = A * pt.X + B * pt.Y - C;
|
|
return (C * C) / (A * A + B * B);
|
|
}
|
|
|
|
|
|
// ---------------------------------------------------------------------------
|
|
|
|
bool SlopesNearCollinear( const IntPoint& pt1,
|
|
const IntPoint& pt2, const IntPoint& pt3, double distSqrd )
|
|
{
|
|
// this function is more accurate when the point that's geometrically
|
|
// between the other 2 points is the one that's tested for distance.
|
|
// ie makes it more likely to pick up 'spikes' ...
|
|
if( Abs( pt1.X - pt2.X ) > Abs( pt1.Y - pt2.Y ) )
|
|
{
|
|
if( (pt1.X > pt2.X) == (pt1.X < pt3.X) )
|
|
return DistanceFromLineSqrd( pt1, pt2, pt3 ) < distSqrd;
|
|
else if( (pt2.X > pt1.X) == (pt2.X < pt3.X) )
|
|
return DistanceFromLineSqrd( pt2, pt1, pt3 ) < distSqrd;
|
|
else
|
|
return DistanceFromLineSqrd( pt3, pt1, pt2 ) < distSqrd;
|
|
}
|
|
else
|
|
{
|
|
if( (pt1.Y > pt2.Y) == (pt1.Y < pt3.Y) )
|
|
return DistanceFromLineSqrd( pt1, pt2, pt3 ) < distSqrd;
|
|
else if( (pt2.Y > pt1.Y) == (pt2.Y < pt3.Y) )
|
|
return DistanceFromLineSqrd( pt2, pt1, pt3 ) < distSqrd;
|
|
else
|
|
return DistanceFromLineSqrd( pt3, pt1, pt2 ) < distSqrd;
|
|
}
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
bool PointsAreClose( IntPoint pt1, IntPoint pt2, double distSqrd )
|
|
{
|
|
double Dx = (double) pt1.X - pt2.X;
|
|
double dy = (double) pt1.Y - pt2.Y;
|
|
|
|
return (Dx * Dx) + (dy * dy) <= distSqrd;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
OutPt* ExcludeOp( OutPt* op )
|
|
{
|
|
OutPt* result = op->Prev;
|
|
|
|
result->Next = op->Next;
|
|
op->Next->Prev = result;
|
|
result->Idx = 0;
|
|
return result;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void CleanPolygon( const Path& in_poly, Path& out_poly, double distance )
|
|
{
|
|
// distance = proximity in units/pixels below which vertices
|
|
// will be stripped. Default ~= sqrt(2).
|
|
|
|
size_t size = in_poly.size();
|
|
|
|
if( size == 0 )
|
|
{
|
|
out_poly.clear();
|
|
return;
|
|
}
|
|
|
|
OutPt* outPts = new OutPt[size];
|
|
|
|
for( size_t i = 0; i < size; ++i )
|
|
{
|
|
outPts[i].Pt = in_poly[i];
|
|
outPts[i].Next = &outPts[(i + 1) % size];
|
|
outPts[i].Next->Prev = &outPts[i];
|
|
outPts[i].Idx = 0;
|
|
}
|
|
|
|
double distSqrd = distance * distance;
|
|
OutPt* op = &outPts[0];
|
|
|
|
while( op->Idx == 0 && op->Next != op->Prev )
|
|
{
|
|
if( PointsAreClose( op->Pt, op->Prev->Pt, distSqrd ) )
|
|
{
|
|
op = ExcludeOp( op );
|
|
size--;
|
|
}
|
|
else if( PointsAreClose( op->Prev->Pt, op->Next->Pt, distSqrd ) )
|
|
{
|
|
ExcludeOp( op->Next );
|
|
op = ExcludeOp( op );
|
|
size -= 2;
|
|
}
|
|
else if( SlopesNearCollinear( op->Prev->Pt, op->Pt, op->Next->Pt, distSqrd ) )
|
|
{
|
|
op = ExcludeOp( op );
|
|
size--;
|
|
}
|
|
else
|
|
{
|
|
op->Idx = 1;
|
|
op = op->Next;
|
|
}
|
|
}
|
|
|
|
if( size < 3 )
|
|
size = 0;
|
|
|
|
out_poly.resize( size );
|
|
|
|
for( size_t i = 0; i < size; ++i )
|
|
{
|
|
out_poly[i] = op->Pt;
|
|
op = op->Next;
|
|
}
|
|
|
|
delete [] outPts;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void CleanPolygon( Path& poly, double distance )
|
|
{
|
|
CleanPolygon( poly, poly, distance );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void CleanPolygons( const Paths& in_polys, Paths& out_polys, double distance )
|
|
{
|
|
out_polys.resize( in_polys.size() );
|
|
|
|
for( Paths::size_type i = 0; i < in_polys.size(); ++i )
|
|
CleanPolygon( in_polys[i], out_polys[i], distance );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void CleanPolygons( Paths& polys, double distance )
|
|
{
|
|
CleanPolygons( polys, polys, distance );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void Minkowski( const Path& poly, const Path& path,
|
|
Paths& solution, bool isSum, bool isClosed )
|
|
{
|
|
int delta = (isClosed ? 1 : 0);
|
|
size_t polyCnt = poly.size();
|
|
size_t pathCnt = path.size();
|
|
Paths pp;
|
|
|
|
pp.reserve( pathCnt );
|
|
|
|
if( isSum )
|
|
for( size_t i = 0; i < pathCnt; ++i )
|
|
{
|
|
Path p;
|
|
p.reserve( polyCnt );
|
|
|
|
for( size_t j = 0; j < poly.size(); ++j )
|
|
p.push_back( IntPoint( path[i].X + poly[j].X, path[i].Y + poly[j].Y ) );
|
|
|
|
pp.push_back( p );
|
|
}
|
|
|
|
|
|
else
|
|
for( size_t i = 0; i < pathCnt; ++i )
|
|
{
|
|
Path p;
|
|
p.reserve( polyCnt );
|
|
|
|
for( size_t j = 0; j < poly.size(); ++j )
|
|
p.push_back( IntPoint( path[i].X - poly[j].X, path[i].Y - poly[j].Y ) );
|
|
|
|
pp.push_back( p );
|
|
}
|
|
|
|
|
|
|
|
solution.clear();
|
|
solution.reserve( (pathCnt + delta) * (polyCnt + 1) );
|
|
|
|
for( size_t i = 0; i < pathCnt - 1 + delta; ++i )
|
|
for( size_t j = 0; j < polyCnt; ++j )
|
|
{
|
|
Path quad;
|
|
quad.reserve( 4 );
|
|
quad.push_back( pp[i % pathCnt][j % polyCnt] );
|
|
quad.push_back( pp[(i + 1) % pathCnt][j % polyCnt] );
|
|
quad.push_back( pp[(i + 1) % pathCnt][(j + 1) % polyCnt] );
|
|
quad.push_back( pp[i % pathCnt][(j + 1) % polyCnt] );
|
|
|
|
if( !Orientation( quad ) )
|
|
ReversePath( quad );
|
|
|
|
solution.push_back( quad );
|
|
}
|
|
|
|
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void MinkowskiSum( const Path& pattern, const Path& path, Paths& solution, bool pathIsClosed )
|
|
{
|
|
Minkowski( pattern, path, solution, true, pathIsClosed );
|
|
Clipper c;
|
|
c.AddPaths( solution, ptSubject, true );
|
|
c.Execute( ctUnion, solution, pftNonZero, pftNonZero );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void TranslatePath( const Path& input, Path& output, const IntPoint delta )
|
|
{
|
|
// precondition: input != output
|
|
output.resize( input.size() );
|
|
|
|
for( size_t i = 0; i < input.size(); ++i )
|
|
output[i] = IntPoint( input[i].X + delta.X, input[i].Y + delta.Y );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void MinkowskiSum( const Path& pattern, const Paths& paths, Paths& solution, bool pathIsClosed )
|
|
{
|
|
Clipper c;
|
|
|
|
for( size_t i = 0; i < paths.size(); ++i )
|
|
{
|
|
Paths tmp;
|
|
Minkowski( pattern, paths[i], tmp, true, pathIsClosed );
|
|
c.AddPaths( tmp, ptSubject, true );
|
|
|
|
if( pathIsClosed )
|
|
{
|
|
Path tmp2;
|
|
TranslatePath( paths[i], tmp2, pattern[0] );
|
|
c.AddPath( tmp2, ptClip, true );
|
|
}
|
|
}
|
|
|
|
c.Execute( ctUnion, solution, pftNonZero, pftNonZero );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void MinkowskiDiff( const Path& poly1, const Path& poly2, Paths& solution )
|
|
{
|
|
Minkowski( poly1, poly2, solution, false, true );
|
|
Clipper c;
|
|
c.AddPaths( solution, ptSubject, true );
|
|
c.Execute( ctUnion, solution, pftNonZero, pftNonZero );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
enum NodeType
|
|
{
|
|
ntAny, ntOpen, ntClosed
|
|
};
|
|
|
|
void AddPolyNodeToPaths( const PolyNode& polynode, NodeType nodetype, Paths& paths )
|
|
{
|
|
bool match = true;
|
|
|
|
if( nodetype == ntClosed )
|
|
match = !polynode.IsOpen();
|
|
else if( nodetype == ntOpen )
|
|
return;
|
|
|
|
if( !polynode.Contour.empty() && match )
|
|
paths.push_back( polynode.Contour );
|
|
|
|
for( int i = 0; i < polynode.ChildCount(); ++i )
|
|
AddPolyNodeToPaths( *polynode.Childs[i], nodetype, paths );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void PolyTreeToPaths( const PolyTree& polytree, Paths& paths )
|
|
{
|
|
paths.resize( 0 );
|
|
paths.reserve( polytree.Total() );
|
|
AddPolyNodeToPaths( polytree, ntAny, paths );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void ClosedPathsFromPolyTree( const PolyTree& polytree, Paths& paths )
|
|
{
|
|
paths.resize( 0 );
|
|
paths.reserve( polytree.Total() );
|
|
AddPolyNodeToPaths( polytree, ntClosed, paths );
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
void OpenPathsFromPolyTree( PolyTree& polytree, Paths& paths )
|
|
{
|
|
paths.resize( 0 );
|
|
paths.reserve( polytree.Total() );
|
|
|
|
// Open paths are top level only, so ...
|
|
for( int i = 0; i < polytree.ChildCount(); ++i )
|
|
if( polytree.Childs[i]->IsOpen() )
|
|
paths.push_back( polytree.Childs[i]->Contour );
|
|
|
|
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
std::ostream& operator <<( std::ostream& s, const IntPoint& p )
|
|
{
|
|
s << "(" << p.X << "," << p.Y << ")";
|
|
return s;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
std::ostream& operator <<( std::ostream& s, const Path& p )
|
|
{
|
|
if( p.empty() )
|
|
return s;
|
|
|
|
Path::size_type last = p.size() - 1;
|
|
|
|
for( Path::size_type i = 0; i < last; i++ )
|
|
s << "(" << p[i].X << "," << p[i].Y << "), ";
|
|
|
|
s << "(" << p[last].X << "," << p[last].Y << ")\n";
|
|
return s;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
|
|
std::ostream& operator <<( std::ostream& s, const Paths& p )
|
|
{
|
|
for( Paths::size_type i = 0; i < p.size(); i++ )
|
|
s << p[i];
|
|
|
|
s << "\n";
|
|
return s;
|
|
}
|
|
|
|
|
|
// ------------------------------------------------------------------------------
|
|
} // ClipperLib namespace
|