GEOS  3.8.0dev
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geos::noding::snapround::SimpleSnapRounder Class Reference

Uses Snap Rounding to compute a rounded, fully noded arrangement from a set of SegmentStrings. More...

#include <SimpleSnapRounder.h>

Inheritance diagram for geos::noding::snapround::SimpleSnapRounder:
geos::noding::Noder

Public Member Functions

 SimpleSnapRounder (const geom::PrecisionModel &newPm)
 
std::vector< SegmentString * > * getNodedSubstrings () const override
 Returns a collection of fully noded SegmentStrings. The SegmentStrings have the same context as their parent. More...
 
void computeNodes (std::vector< SegmentString * > *inputSegmentStrings) override
 Computes the noding for a collection of SegmentStrings. More...
 
void add (const SegmentString *segStr)
 
void computeVertexSnaps (const std::vector< SegmentString * > &edges)
 

Detailed Description

Uses Snap Rounding to compute a rounded, fully noded arrangement from a set of SegmentStrings.

Implements the Snap Rounding technique described in Hobby, Guibas & Marimont, and Goodrich et al. Snap Rounding assumes that all vertices lie on a uniform grid (hence the precision model of the input must be fixed precision, and all the input vertices must be rounded to that precision).

This implementation uses simple iteration over the line segments.

This implementation appears to be fully robust using an integer precision model. It will function with non-integer precision models, but the results are not 100% guaranteed to be correctly noded.

Member Function Documentation

void geos::noding::snapround::SimpleSnapRounder::computeNodes ( std::vector< SegmentString * > *  segStrings)
overridevirtual

Computes the noding for a collection of SegmentStrings.

Some Noders may add all these nodes to the input SegmentStrings; others may only add some or none at all.

Parameters
segStringsa collection of SegmentStrings to node

Implements geos::noding::Noder.

void geos::noding::snapround::SimpleSnapRounder::computeVertexSnaps ( const std::vector< SegmentString * > &  edges)

Computes nodes introduced as a result of snapping segments to vertices of other segments

Parameters
edgesthe list of segment strings to snap together. Must be NodedSegmentString or an assertion will fail.
std::vector<SegmentString*>* geos::noding::snapround::SimpleSnapRounder::getNodedSubstrings ( ) const
overridevirtual

Returns a collection of fully noded SegmentStrings. The SegmentStrings have the same context as their parent.

Returns
a newly allocated std::vector of const SegmentStrings. Caller is responsible to delete container and elements.

Implements geos::noding::Noder.


The documentation for this class was generated from the following file: