GEOS  3.9.1
SimpleMCSweepLineIntersector.h
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15 
16 #ifndef GEOS_GEOMGRAPH_INDEX_SIMPLEMCSWEEPLINEINTERSECTOR_H
17 #define GEOS_GEOMGRAPH_INDEX_SIMPLEMCSWEEPLINEINTERSECTOR_H
18 
19 #include <geos/export.h>
20 #include <memory>
21 #include <vector>
22 
23 #include <geos/geomgraph/index/EdgeSetIntersector.h> // for inheritance
24 #include <geos/geomgraph/index/SegmentIntersector.h>
25 #include <geos/geomgraph/index/SweepLineEvent.h>
26 #include <geos/geomgraph/index/MonotoneChain.h>
27 
28 #ifdef _MSC_VER
29 #pragma warning(push)
30 #pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class
31 #endif
32 
33 // Forward declarations
34 namespace geos {
35 namespace geomgraph {
36 class Edge;
37 }
38 }
39 
40 namespace geos {
41 namespace geomgraph { // geos::geomgraph
42 namespace index { // geos::geomgraph::index
43 
54 
55 public:
56 
57  SimpleMCSweepLineIntersector() = default;
58 
59  ~SimpleMCSweepLineIntersector() override = default;
60 
61  void computeIntersections(std::vector<Edge*>* edges,
62  SegmentIntersector* si, bool testAllSegments) override;
63 
64  void computeIntersections(std::vector<Edge*>* edges0,
65  std::vector<Edge*>* edges1,
66  SegmentIntersector* si) override;
67 
68 protected:
69 
70  // SweepLineEvents need to refer to each other, and to MonotoneChains.
71  // To avoid individually heap-allocating all of these, we store them
72  // in deques so that subsequent inserts preserve addresses. However,
73  // we also need to sort the SweepLineEvents after they have all been
74  // inserted, so we keep a pointer to each event in a separate vector,
75  // which can be freely reordered without breaking linkages.
76  std::vector<SweepLineEvent*> events;
77  std::deque<SweepLineEvent> eventStore;
78  std::deque<MonotoneChain> chains;
79 
80  // statistics information
81  int nOverlaps;
82 
83 private:
84  void add(std::vector<Edge*>* edges);
85 
86  void add(std::vector<Edge*>* edges, void* edgeSet);
87 
88  void add(Edge* edge, void* edgeSet);
89 
90  void prepareEvents();
91 
92  void computeIntersections(SegmentIntersector* si);
93 
94  void processOverlaps(size_t start, size_t end,
95  SweepLineEvent* ev0,
96  SegmentIntersector* si);
97  // Declare type as noncopyable
99  SimpleMCSweepLineIntersector& operator=(const SimpleMCSweepLineIntersector& rhs) = delete;
100 };
101 
102 } // namespace geos.geomgraph.index
103 } // namespace geos.geomgraph
104 } // namespace geos
105 
106 #ifdef _MSC_VER
107 #pragma warning(pop)
108 #endif
109 
110 #endif // GEOS_GEOMGRAPH_INDEX_SIMPLEMCSWEEPLINEINTERSECTOR_H
111 
Definition: geomgraph/Edge.h:66
An EdgeSetIntersector computes all the intersections between the edges in the set.
Definition: EdgeSetIntersector.h:41
Computes the intersection of line segments, and adds the intersection to the edges containing the seg...
Definition: geomgraph/index/SegmentIntersector.h:47
Finds all intersections in one or two sets of edges, using an x-axis sweepline algorithm in conjuncti...
Definition: SimpleMCSweepLineIntersector.h:53
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: IndexedNestedRingTester.h:26