GEOS  3.13.0dev
SimpleMCSweepLineIntersector.h
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6  * Copyright (C) 2005-2006 Refractions Research Inc.
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15 
16 #pragma once
17 
18 #include <geos/export.h>
19 #include <memory>
20 #include <vector>
21 
22 #include <geos/geomgraph/index/EdgeSetIntersector.h> // for inheritance
23 #include <geos/geomgraph/index/SegmentIntersector.h>
24 #include <geos/geomgraph/index/SweepLineEvent.h>
25 #include <geos/geomgraph/index/MonotoneChain.h>
26 
27 #ifdef _MSC_VER
28 #pragma warning(push)
29 #pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class
30 #endif
31 
32 // Forward declarations
33 namespace geos {
34 namespace geomgraph {
35 class Edge;
36 }
37 }
38 
39 namespace geos {
40 namespace geomgraph { // geos::geomgraph
41 namespace index { // geos::geomgraph::index
42 
53 
54 public:
55 
56  SimpleMCSweepLineIntersector() = default;
57 
58  ~SimpleMCSweepLineIntersector() override = default;
59 
60  void computeIntersections(std::vector<Edge*>* edges,
61  SegmentIntersector* si, bool testAllSegments) override;
62 
63  void computeIntersections(std::vector<Edge*>* edges0,
64  std::vector<Edge*>* edges1,
65  SegmentIntersector* si) override;
66 
67 protected:
68 
69  // SweepLineEvents need to refer to each other, and to MonotoneChains.
70  // To avoid individually heap-allocating all of these, we store them
71  // in deques so that subsequent inserts preserve addresses. However,
72  // we also need to sort the SweepLineEvents after they have all been
73  // inserted, so we keep a pointer to each event in a separate vector,
74  // which can be freely reordered without breaking linkages.
75  std::vector<SweepLineEvent*> events;
76  std::deque<SweepLineEvent> eventStore;
77  std::deque<MonotoneChain> chains;
78 
79  // statistics information
80  int nOverlaps;
81 
82 private:
83  void add(std::vector<Edge*>* edges);
84 
85  void add(std::vector<Edge*>* edges, void* edgeSet);
86 
87  void add(Edge* edge, void* edgeSet);
88 
89  void prepareEvents();
90 
91  void computeIntersections(SegmentIntersector* si);
92 
93  void processOverlaps(std::size_t start, std::size_t end,
94  SweepLineEvent* ev0,
95  SegmentIntersector* si);
96  // Declare type as noncopyable
98  SimpleMCSweepLineIntersector& operator=(const SimpleMCSweepLineIntersector& rhs) = delete;
99 };
100 
101 } // namespace geos.geomgraph.index
102 } // namespace geos.geomgraph
103 } // namespace geos
104 
105 #ifdef _MSC_VER
106 #pragma warning(pop)
107 #endif
108 
Definition: geomgraph/Edge.h:63
An EdgeSetIntersector computes all the intersections between the edges in the set.
Definition: EdgeSetIntersector.h:40
Computes the intersection of line segments, and adds the intersection to the edges containing the seg...
Definition: geomgraph/index/SegmentIntersector.h:46
Finds all intersections in one or two sets of edges, using an x-axis sweepline algorithm in conjuncti...
Definition: SimpleMCSweepLineIntersector.h:52
void computeIntersections(std::vector< Edge * > *edges, SegmentIntersector *si, bool testAllSegments) override
Computes all self-intersections between edges in a set of edges, allowing client to choose whether se...
void computeIntersections(std::vector< Edge * > *edges0, std::vector< Edge * > *edges1, SegmentIntersector *si) override
Computes all mutual intersections between two sets of edges.
Basic namespace for all GEOS functionalities.
Definition: Angle.h:25