Class SimpleMCSweepLineIntersector
java.lang.Object
org.locationtech.jts.geomgraph.index.EdgeSetIntersector
org.locationtech.jts.geomgraph.index.SimpleMCSweepLineIntersector
Finds all intersections in one or two sets of edges,
using an x-axis sweepline algorithm in conjunction with Monotone Chains.
While still O(n^2) in the worst case, this algorithm
drastically improves the average-case time.
The use of MonotoneChains as the items in the index
seems to offer an improvement in performance over a sweep-line alone.
- Version:
- 1.7
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Field Summary
Fields -
Constructor Summary
ConstructorsConstructorDescriptionA SimpleMCSweepLineIntersector creates monotone chains from the edges and compares them using a simple sweep-line along the x-axis. -
Method Summary
Modifier and TypeMethodDescriptionprivate void
private void
private void
void
computeIntersections
(List edges0, List edges1, SegmentIntersector si) Computes all mutual intersections between two sets of edges.void
computeIntersections
(List edges, SegmentIntersector si, boolean testAllSegments) Computes all self-intersections between edges in a set of edges, allowing client to choose whether self-intersections are computed.private void
private void
Because Delete Events have a link to their corresponding Insert event, it is possible to compute exactly the range of events which must be compared to a given Insert event object.private void
processOverlaps
(int start, int end, SweepLineEvent ev0, SegmentIntersector si)
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Field Details
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events
List events -
nOverlaps
int nOverlaps
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Constructor Details
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SimpleMCSweepLineIntersector
public SimpleMCSweepLineIntersector()A SimpleMCSweepLineIntersector creates monotone chains from the edges and compares them using a simple sweep-line along the x-axis.
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Method Details
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computeIntersections
Description copied from class:EdgeSetIntersector
Computes all self-intersections between edges in a set of edges, allowing client to choose whether self-intersections are computed.- Specified by:
computeIntersections
in classEdgeSetIntersector
- Parameters:
edges
- a list of edges to test for intersectionssi
- the SegmentIntersector to usetestAllSegments
- true if self-intersections are to be tested as well
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computeIntersections
Description copied from class:EdgeSetIntersector
Computes all mutual intersections between two sets of edges.- Specified by:
computeIntersections
in classEdgeSetIntersector
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addEdges
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addEdges
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addEdge
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prepareEvents
private void prepareEvents()Because Delete Events have a link to their corresponding Insert event, it is possible to compute exactly the range of events which must be compared to a given Insert event object. -
computeIntersections
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processOverlaps
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