Jump to Content

Class PolylineSimplifier

PolylineSimplifier (API Reference)

java.lang.Object
- com.here.NativeBase
- - com.here.sdk.core.PolylineSimplifier

```
public final class PolylineSimplifier
extends NativeBase
```
PolylineSimplifier helps to reduce the number of points in the polyline by removing redundant elements using Douglas–Peucker algorithm, so that result stays within PolylineSimplifier.Options.
Typical use case is to perform input preparation step before invoking computationally heavy API. Such API have an upper limit on the input collection size and is subject to reduced performance when collection is huge. Examples of such API are:
- TrafficEngine methods which accept a GeoCorridor;
- RoutePrefetcher.prefetchGeoCorridor.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`PolylineSimplifier.Options`	Controls the strategy of `simplify(java.util.List<com.here.sdk.core.GeoCoordinates>, com.here.sdk.core.PolylineSimplifier.Options, com.here.sdk.core.PolylineSimplificationCallback)` when reducing a size of polyline.

Constructor Summary

Constructors
Constructor Description

PolylineSimplifier()
Creates a new instance of PolylineSimplifier.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`TaskHandle`	`simplify(java.util.List<GeoCoordinates> polyline, PolylineSimplifier.Options simplificationParameters, PolylineSimplificationCallback callback)`	Reduces the number of points in the input polyline.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - PolylineSimplifier
```
public PolylineSimplifier()
                   throws InstantiationErrorException
```
    Creates a new instance of PolylineSimplifier.
    
    Throws:
    
    InstantiationErrorException -
    Indicates what went wrong when the instantiation was attempted.
- Method Detail
  - simplify
```
@NonNull
public TaskHandle simplify(@NonNull
                           java.util.List<GeoCoordinates> polyline,
                           @NonNull
                           PolylineSimplifier.Options simplificationParameters,
                           @NonNull
                           PolylineSimplificationCallback callback)
```
    Reduces the number of points in the input polyline. Does this by removing points which are not significant according to the passed PolylineSimplifier.Options. Simplification process is performed on the device without connecting to the network and is computationally intensive.
    
    Parameters:
    
    polyline -
    Input polyline that should be reduced in size.
    
    simplificationParameters -
    Strategy, that controls the behavior of the underlying algorithm.
    
    callback -
    Callback, which will be invoked on the main thread, when operation is finished.
    
    Returns:
    
    Controls an asynchronous operation.