FlatteningPathIterator (Java SE 25 & JDK 25)
Description: declaration: module: java.desktop, package: java.awt.geom, class: FlatteningPathIterator
Keywords: java.awt.geom.FlatteningPathIterator class

# Class FlatteningPathIterator

java.lang.Object
java.awt.geom.FlatteningPathIterator

All Implemented Interfaces:
  `PathIterator`

public class FlatteningPathIterator extends Object implements PathIterator
The `FlatteningPathIterator` class returns a flattened view of another `PathIterator` object. Other `Shape` classes can use this class to provide flattening behavior for their paths without having to perform the interpolation calculations themselves.

- ## Field Summary

  ### Fields declared in interface PathIterator

  `SEG_CLOSE, SEG_CUBICTO, SEG_LINETO, SEG_MOVETO, SEG_QUADTO, WIND_EVEN_ODD, WIND_NON_ZERO`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `FlatteningPathIterator(PathIterator src, double flatness)`
  Constructs a new `FlatteningPathIterator` object that flattens a path as it iterates over it.
  `FlatteningPathIterator(PathIterator src, double flatness, int limit)`
  Constructs a new `FlatteningPathIterator` object that flattens a path as it iterates over it.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `int`
  `currentSegment(double[] coords)`
  Returns the coordinates and type of the current path segment in the iteration.
  `int`
  `currentSegment(float[] coords)`
  Returns the coordinates and type of the current path segment in the iteration.
  `double`
  `getFlatness()`
  Returns the flatness of this iterator.
  `int`
  `getRecursionLimit()`
  Returns the recursion limit of this iterator.
  `int`
  `getWindingRule()`
  Returns the winding rule for determining the interior of the path.
  `boolean`
  `isDone()`
  Tests if the iteration is complete.
  `void`
  `next()`
  Moves the iterator to the next segment of the path forwards along the primary direction of traversal as long as there are more points in that direction.

  ### Methods declared in class Object

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

- ## Constructor Details

  - ### FlatteningPathIterator

    public FlatteningPathIterator(PathIterator src, double flatness)
    Constructs a new `FlatteningPathIterator` object that flattens a path as it iterates over it. The iterator does not subdivide any curve read from the source iterator to more than 10 levels of subdivision which yields a maximum of 1024 line segments per curve.
    Parameters:
      `src` - the original unflattened path being iterated over
      `flatness` - the maximum allowable distance between the control points and the flattened curve

  - ### FlatteningPathIterator

    public FlatteningPathIterator(PathIterator src, double flatness, int limit)
    Constructs a new `FlatteningPathIterator` object that flattens a path as it iterates over it. The `limit` parameter allows you to control the maximum number of recursive subdivisions that the iterator can make before it assumes that the curve is flat enough without measuring against the `flatness` parameter. The flattened iteration therefore never generates more than a maximum of `(2^limit)` line segments per curve.
    Parameters:
      `src` - the original unflattened path being iterated over
      `flatness` - the maximum allowable distance between the control points and the flattened curve
      `limit` - the maximum number of recursive subdivisions allowed for any curved segment
    Throws:
      `IllegalArgumentException` - if `flatness` or `limit` is less than zero

- ## Method Details

  - ### getFlatness

    public double getFlatness()
    Returns the flatness of this iterator.
    Returns:
      the flatness of this `FlatteningPathIterator`.

  - ### getRecursionLimit

    public int getRecursionLimit()
    Returns the recursion limit of this iterator.
    Returns:
      the recursion limit of this `FlatteningPathIterator`.

  - ### getWindingRule

    public int getWindingRule()
    Returns the winding rule for determining the interior of the path.
    Specified by:
      `getWindingRule` in interface `PathIterator`
    Returns:
      the winding rule of the original unflattened path being iterated over.
    See Also:
      - `PathIterator.WIND_EVEN_ODD`
      - `PathIterator.WIND_NON_ZERO`

  - ### isDone

    public boolean isDone()
    Tests if the iteration is complete.
    Specified by:
      `isDone` in interface `PathIterator`
    Returns:
      `true` if all the segments have been read; `false` otherwise.

  - ### next

    public void next()
    Moves the iterator to the next segment of the path forwards along the primary direction of traversal as long as there are more points in that direction.
    Specified by:
      `next` in interface `PathIterator`

  - ### currentSegment

    public int currentSegment(float[] coords)
    Returns the coordinates and type of the current path segment in the iteration. The return value is the path segment type: SEG_MOVETO, SEG_LINETO, or SEG_CLOSE. A float array of length 6 must be passed in and can be used to store the coordinates of the point(s). Each point is stored as a pair of float x,y coordinates. SEG_MOVETO and SEG_LINETO types return one point, and SEG_CLOSE does not return any points.
    Specified by:
      `currentSegment` in interface `PathIterator`
    Parameters:
      `coords` - an array that holds the data returned from this method
    Returns:
      the path segment type of the current path segment.
    Throws:
      `NoSuchElementException` - if there are no more elements in the flattening path to be returned.
    See Also:
      - `PathIterator.SEG_MOVETO`
      - `PathIterator.SEG_LINETO`
      - `PathIterator.SEG_CLOSE`

  - ### currentSegment

    public int currentSegment(double[] coords)
    Returns the coordinates and type of the current path segment in the iteration. The return value is the path segment type: SEG_MOVETO, SEG_LINETO, or SEG_CLOSE. A double array of length 6 must be passed in and can be used to store the coordinates of the point(s). Each point is stored as a pair of double x,y coordinates. SEG_MOVETO and SEG_LINETO types return one point, and SEG_CLOSE does not return any points.
    Specified by:
      `currentSegment` in interface `PathIterator`
    Parameters:
      `coords` - an array that holds the data returned from this method
    Returns:
      the path segment type of the current path segment.
    Throws:
      `NoSuchElementException` - if there are no more elements in the flattening path to be returned.
    See Also:
      - `PathIterator.SEG_MOVETO`
      - `PathIterator.SEG_LINETO`
      - `PathIterator.SEG_CLOSE`