VertexClusterReduction (dyn4j 5.0.2 API)

Object
- AbstractSimplifier
- - VertexClusterReduction

All Implemented Interfaces:

Simplifier

Direct Known Subclasses:

DouglasPeucker, Visvalingam
```
public class VertexClusterReduction
extends AbstractSimplifier
implements Simplifier
```
Simple polygon (without holes) simplifier that reduces the number of vertices by inspecting the distance between adjacent vertices. If the distance between two adjacent vertices is less than the given tolerance, it's removed.
This algorithm is typically used to pre-process a simple polygon before another simplification algorithm is used. Both the Visvalingam and DouglasPeucker implementations run this step before running their algorithm.
This algorithm has O(n log n) complexity where n is the number of vertices in the source polygon (due to self-intersection prevention). This algorithm prevents self-intersections arising from the simplification process by skipping the simplification.
This method does not require the polygon to have any defined winding, but does assume that it does not have holes and is not self-intersecting.
This method handles null/empty lists, null elements, and all null elements. In these cases it's possible the returned list will be empty or have less than 3 vertices.
NOTE: This algorithm's result is highly dependent on the given cluster tolerance and the input polygon. There's no guarantee that the result will have 3 or more vertices.

Since:

4.2.0

Version:

5.0.0

Author:

William Bittle

See Also:

Vertex Cluster Reduction

Constructor Summary

Constructors
Constructor Description

VertexClusterReduction(double clusterTolerance)
Minimal constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected List<SimplePolygonVertex>`	`buildVertexList(List<Vector2> polygon)`	Builds a list of vertices without nulls.
`List<Vector2>`	`simplify(List<Vector2> vertices)`	Simplifies the given simple polygon and returns a new simplified simple polygon.

Methods inherited from class AbstractSimplifier
buildResult, buildSegmentTree, intersects, isSelfIntersectionProduced, isSelfIntersectionProduced, simplify

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

Methods inherited from interface Simplifier
simplify

- Constructor Detail
  - VertexClusterReduction
```
public VertexClusterReduction(double clusterTolerance)
```
    Minimal constructor.
    
    Parameters:
    
    clusterTolerance - the minimal distance allowed between adjacent vertices; must be zero or greater
    
    Throws:
    
    IllegalArgumentException - if clusterTolerance is less than zero
- Method Detail
  - simplify
```
public List<Vector2> simplify(List<Vector2> vertices)
```
    Description copied from interface: Simplifier
    
    Simplifies the given simple polygon and returns a new simplified simple polygon.
    
    Specified by:
    
    simplify in interface Simplifier
    
    Parameters:
    
    vertices - the simple polygon's vertices
    
    Returns:
    
    List<Vector2>
  - buildVertexList
```
protected final List<SimplePolygonVertex> buildVertexList(List<Vector2> polygon)
```
    Builds a list of vertices without nulls.
    
    Parameters:
    
    polygon - the polygon vertices
    
    Returns:
    
    List<SimplePolygonVertex>