Package com.luciad.geometries.observable

Class ObservablePolylineRingUtil

java.lang.Object

com.luciad.geometries.observable.ObservablePolylineRingUtil

public final class ObservablePolylineRingUtil
extends Object

This class provides utility methods for Observable instance for PolylineRing.

Method Summary

Modifier and Type	Method	Description
static Observable<@Nullable Point>	derivePointAtIndex(Observable<@Nullable PolylineRing> observablePolylineRing, long index)	Derives an Observable Point from the given observable polyline ring that represents the point at the given index.
static Observable<@Nullable Point>	derivePointOnSegment(Observable<@Nullable PolylineRing> observablePolylineRing, long segmentIndex, double parameter)	Derives an Observable Point from the given observable polyline ring that represents a point on a segment of the polyline ring.

Methods inherited from class java.lang.Object

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

Method Details

derivePointAtIndex

@NotNull
public static Observable<@Nullable Point> derivePointAtIndex(@NotNull
 Observable<@Nullable PolylineRing> observablePolylineRing,
 long index)

Derives an Observable Point from the given observable polyline ring that represents the point at the given index.

This observable point will be updated when the given observable polyline ring changes.

Notes:

• When the observable polyline ring contains a null value, the observable point instance will contain a null value too.
• When the given index >= point count, the observable point instance will contain a null value.
• Observable#setValue will throw an exception for derived instances.

Parameters:

observablePolylineRing - an observable polyline ring from which to derive the point

index - the point index

Returns:

a derived Observable

derivePointOnSegment

@NotNull
public static Observable<@Nullable Point> derivePointOnSegment(@NotNull
 Observable<@Nullable PolylineRing> observablePolylineRing,
 long segmentIndex,
 double parameter)

Derives an Observable Point from the given observable polyline ring that represents a point on a segment of the polyline ring.

This observable point will be updated when the given observable polyline ring changes.

Notes:

• When the observable polyline ring contains a null value, the observable point instance will contain a null value too.
• When the given segmentIndex >= point count, the observable point instance will contain a null value.
• Observable#setValue will throw an exception for derived instances.

Parameters:

observablePolylineRing - an observable polyline ring from which to derive the point

segmentIndex - a segment index: a value between [0, pointCount - 2]. For example: segment index 0 corresponds with the segment between the points with index 0 and 1.

parameter - a parameter value between [0, 1] that determines which point of the segment is chosen. This can for example be 0.5, to get the middle of the segment

Returns:

a derived Observable