Package org.locationtech.jts.algorithm

Class ConvexHull.RadialComparator

java.lang.Object

org.locationtech.jts.algorithm.ConvexHull.RadialComparator

All Implemented Interfaces:

Comparator

Enclosing class:

ConvexHull

private static class ConvexHull.RadialComparator
extends Object
implements Comparator

Compares Coordinates for their angle and distance relative to an origin.

Version:

1.7

Field Summary

Fields

Modifier and Type	Field	Description
private Coordinate	origin

Constructor Summary

Constructors

Constructor	Description
RadialComparator(Coordinate origin)

Method Summary

Modifier and Type	Method	Description
int	compare(Object o1, Object o2)
private static int	polarCompare(Coordinate o, Coordinate p, Coordinate q)	Given two points p and q compare them with respect to their radial ordering about point o.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Field Details

origin

private Coordinate origin

Constructor Details

RadialComparator

public RadialComparator(Coordinate origin)

Method Details

compare

public int compare(Object o1,
 Object o2)

Specified by:

compare in interface Comparator

polarCompare

private static int polarCompare(Coordinate o,
 Coordinate p,
 Coordinate q)

Given two points p and q compare them with respect to their radial ordering about point o. First checks radial ordering. If points are collinear, the comparison is based on their distance to the origin.

p invalid input: '<' q iff

• ang(o-p) invalid input: '<' ang(o-q) (e.g. o-p-q is CCW)
• or ang(o-p) == ang(o-q) invalid input: '&'invalid input: '&' dist(o,p) invalid input: '<' dist(o,q)

Parameters:

o - the origin

p - a point

q - another point

Returns:

-1, 0 or 1 depending on whether p is less than, equal to or greater than q