org.janusgraph.diskstorage.mixed.utils

Class CircleUtils

java.lang.Object

org.janusgraph.diskstorage.mixed.utils.CircleUtils

public class CircleUtils
extends Object

Utility class for storing different helpful re-usable spatial functions.
The implementation of this class is mostly taken from CircleUtils.java class available in `elasticsearch-geo 8.6.0` library.
The main different is that this util class doesn't use ElasticSearch internal Geometry data structures. Another difference is that this class reuses `SloppyMath.haversinMeters` from Lucene instead of relying on slowHaversin implementation.

Method Summary

Modifier and Type	Method and Description
static int	circleToPolygonNumSides(double radiusMeters, double errorDistanceMeters)
static double[][]	createRegularGeoShapePolygon(double centerCenterLat, double circleCenterLon, double circleRadiusMeters, int gons) Makes an n-gon, centered at the provided circle's center, and each vertex approximately `circleRadius` away from the center.
static double[][]	createRegularShapePolygon(double circleCenterX, double circleCenterY, double circleRadius, int gons) Makes an n-gon, centered at the provided circle's center.

Methods inherited from class java.lang.Object

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

Method Detail

createRegularGeoShapePolygon

public static double[][] createRegularGeoShapePolygon(double centerCenterLat,
                                                      double circleCenterLon,
                                                      double circleRadiusMeters,
                                                      int gons)

Makes an n-gon, centered at the provided circle's center, and each vertex approximately `circleRadius` away from the center. It throws an IllegalArgumentException if the circle contains a pole. This does not split the polygon across the date-line. Adapted from from org.apache.lucene.tests.geo.GeoTestUtil

Returns:

matrix containing 2 arrays. Array with index 0 are Longitude coordinates and array with index 1 are Latitude coordinates.

createRegularShapePolygon

public static double[][] createRegularShapePolygon(double circleCenterX,
                                                   double circleCenterY,
                                                   double circleRadius,
                                                   int gons)

Makes an n-gon, centered at the provided circle's center. This assumes distance measured in cartesian geometry.

Returns:

matrix containing 2 arrays. Array with index 0 are X coordinates and array with index 1 are Y coordinates.

circleToPolygonNumSides

public static int circleToPolygonNumSides(double radiusMeters,
                                          double errorDistanceMeters)