org.locationtech.jts.noding.snapround

Class SnapRoundingIntersectionAdder

java.lang.Object

org.locationtech.jts.noding.snapround.SnapRoundingIntersectionAdder

All Implemented Interfaces:

SegmentIntersector

public class SnapRoundingIntersectionAdder
extends Object
implements SegmentIntersector

Finds intersections between line segments which will be snap-rounded, and adds them as nodes to the segments.

Intersections are detected and computed using full precision. Snapping takes place in a subsequent phase.

The intersection points are recorded, so that HotPixels can be created for them.

To avoid robustness issues with vertices which lie very close to line segments a heuristic is used: nodes are created if a vertex lies within a tolerance distance of the interior of a segment. The tolerance distance is chosen to be significantly below the snap-rounding grid size. This has empirically proven to eliminate noding failures.

Version:

1.17

Constructor Summary

Constructors

Constructor and Description
SnapRoundingIntersectionAdder(PrecisionModel pm) Creates an intersector which finds all snapped interior intersections, and adds them as nodes.

Method Summary

Modifier and Type	Method and Description
List<Coordinate>	getIntersections() Gets the created intersection nodes, so they can be processed as hot pixels.
boolean	isDone() Always process all intersections
void	processIntersections(SegmentString e0, int segIndex0, SegmentString e1, int segIndex1) This method is called by clients of the SegmentIntersector class to process intersections for two segments of the SegmentStrings being intersected.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SnapRoundingIntersectionAdder

public SnapRoundingIntersectionAdder(PrecisionModel pm)

Creates an intersector which finds all snapped interior intersections, and adds them as nodes.

Parameters:

pm - the precision mode to use

Method Detail

getIntersections

public List<Coordinate> getIntersections()

Gets the created intersection nodes, so they can be processed as hot pixels.

Returns:

a list of the intersection points

processIntersections

public void processIntersections(SegmentString e0,
                                 int segIndex0,
                                 SegmentString e1,
                                 int segIndex1)

This method is called by clients of the SegmentIntersector class to process intersections for two segments of the SegmentStrings being intersected. Note that some clients (such as MonotoneChains) may optimize away this call for segment pairs which they have determined do not intersect (e.g. by an disjoint envelope test).

Specified by:

processIntersections in interface SegmentIntersector

isDone

public boolean isDone()

Always process all intersections

Specified by:

isDone in interface SegmentIntersector

Returns:

false always