Package org.apache.commons.geometry.spherical.twod

Class GreatArc

java.lang.Object

org.apache.commons.geometry.spherical.twod.GreatCircleSubset

org.apache.commons.geometry.spherical.twod.GreatArc

All Implemented Interfaces:

Embedding<Point2S,Point1S>, HyperplaneConvexSubset<Point2S>, HyperplaneSubset<Point2S>, Splittable<Point2S,HyperplaneSubset<Point2S>>, RegionEmbedding<Point2S,Point1S>, Sized

public final class GreatArc
extends GreatCircleSubset
implements HyperplaneConvexSubset<Point2S>

Class representing a single, convex angular interval in a GreatCircle. Convex angular intervals are those where the shortest path between all pairs of points in the interval are completely contained in the interval. In the case of paths that tie for the shortest length, it is sufficient that one of the paths is completely contained in the interval. In spherical 2D space, convex arcs either fill the entire great circle or have an angular size of less than or equal to pi radians.

Instances of this class are guaranteed to be immutable.

See Also:

GreatCircles

Field Summary

Fields

Modifier and Type	Field	Description
private AngularInterval.Convex	interval	The interval representing the region of the great circle contained in the arc.

Constructor Summary

Constructors

Constructor	Description
GreatArc(GreatCircle circle, AngularInterval.Convex interval)	Create a new instance from a great circle and the interval embedded in it.

Method Summary

Modifier and Type	Method	Description
Point2S	getEndPoint()	Return the end point of the arc, or null if the arc represents the full space.
AngularInterval.Convex	getInterval()	Get the angular interval for the arc.
Point2S	getMidPoint()	Return the midpoint of the arc, or null if the arc represents the full space.
Point2S	getStartPoint()	Return the start point of the arc, or null if the arc represents the full space.
AngularInterval.Convex	getSubspaceRegion()	Get the embedded subspace region.
GreatArc	reverse()	Reverse the orientation of the hyperplane for this instance, returning the result as a new instance.
Split<GreatArc>	split(Hyperplane<Point2S> splitter)	Split this instance with the given hyperplane.
java.util.List<GreatArc>	toConvex()	Convert this instance into a list of convex child subsets representing the same region.
java.lang.String	toString()	Return a string representation of this great arc.
GreatArc	transform(Transform<Point2S> transform)	Return a new hyperplane subset resulting from the application of the given transform.

Methods inherited from class org.apache.commons.geometry.spherical.twod.GreatCircleSubset

classify, closest, getCentroid, getCircle, getHyperplane, getPrecision, getSize, isEmpty, isFull, toSpace, toSubspace

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.geometry.core.Embedding

toSpace, toSubspace

Methods inherited from interface org.apache.commons.geometry.core.partitioning.HyperplaneSubset

classify, closest, contains, getCentroid, getHyperplane, isEmpty, isFull

Methods inherited from interface org.apache.commons.geometry.core.Sized

getSize, isFinite, isInfinite

Field Detail

interval

private final AngularInterval.Convex interval

The interval representing the region of the great circle contained in the arc.

Constructor Detail

GreatArc

GreatArc(GreatCircle circle,
         AngularInterval.Convex interval)

Create a new instance from a great circle and the interval embedded in it.

Parameters:

circle - defining great circle instance

interval - convex angular interval embedded in the great circle

Method Detail

getStartPoint

public Point2S getStartPoint()

Return the start point of the arc, or null if the arc represents the full space.

Returns:

the start point of the arc, or null if the arc represents the full space.

getEndPoint

public Point2S getEndPoint()

Return the end point of the arc, or null if the arc represents the full space.

Returns:

the end point of the arc, or null if the arc represents the full space.

getMidPoint

public Point2S getMidPoint()

Return the midpoint of the arc, or null if the arc represents the full space.

Returns:

the midpoint of the arc, or null if the arc represents the full space.

getInterval

public AngularInterval.Convex getInterval()

Get the angular interval for the arc.

Returns:

the angular interval for the arc

See Also:

getSubspaceRegion()

getSubspaceRegion

public AngularInterval.Convex getSubspaceRegion()

Get the embedded subspace region.

Specified by:

getSubspaceRegion in interface RegionEmbedding<Point2S,Point1S>

Specified by:

getSubspaceRegion in class GreatCircleSubset

Returns:

the embedded subspace region

toConvex

public java.util.List<GreatArc> toConvex()

Convert this instance into a list of convex child subsets representing the same region. Implementations are not required to return an optimal convex subdivision of the current instance. They are free to return whatever subdivision is readily available.

Specified by:

toConvex in interface HyperplaneSubset<Point2S>

Specified by:

toConvex in class GreatCircleSubset

Returns:

a list of hyperplane convex subsets representing the same subspace region as this instance

split

public Split<GreatArc> split(Hyperplane<Point2S> splitter)

Split this instance with the given hyperplane.

The parts resulting from a split operation with a convex subset are guaranteed to also be convex.

Specified by:

split in interface HyperplaneConvexSubset<Point2S>

Specified by:

split in interface Splittable<Point2S,HyperplaneSubset<Point2S>>

Parameters:

splitter - the hyperplane to split this object with.

Returns:

result of the split operation

transform

public GreatArc transform(Transform<Point2S> transform)

Return a new hyperplane subset resulting from the application of the given transform. The current instance is not modified.

Hyperplane convex subsets subjected to affine transformations remain convex.

Specified by:

transform in interface HyperplaneConvexSubset<Point2S>

Specified by:

transform in interface HyperplaneSubset<Point2S>

Parameters:

transform - the transform instance to apply

Returns:

new transformed hyperplane subset

reverse

public GreatArc reverse()

Reverse the orientation of the hyperplane for this instance, returning the result as a new instance. The returned subset contains the same points but has a reversed orientation.

Specified by:

reverse in interface HyperplaneConvexSubset<Point2S>

Returns:

a hyperplane convex subset representing the same region but with the opposite orientation.

toString

public java.lang.String toString()

Return a string representation of this great arc.

In order to keep the string representation short but useful, the exact format of the return value depends on the properties of the arc. See below for examples.

• Full arc
  • GreatArc[full= true, circle= GreatCircle[pole= (0.0, 0.0, 1.0), x= (1.0, 0.0, 0.0), y= (0.0, 1.0, 0.0)]
• Non-full arc
  • GreatArc[start= (1.0, 1.5707963267948966), end= (2.0, 1.5707963267948966)

Overrides:

toString in class java.lang.Object