java.awt.geom
Class FlatteningPathIterator

java.lang.Object
  extended byjava.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.

Author:
Jim Graham

Field Summary
(package private)  double curx
           
(package private)  double cury
           
(package private)  boolean done
           
(package private) static int GROW_SIZE
           
(package private)  double[] hold
           
(package private)  int holdEnd
           
(package private)  int holdIndex
           
(package private)  int holdType
           
(package private)  int levelIndex
           
(package private)  int[] levels
           
(package private)  int limit
           
(package private)  double movx
           
(package private)  double movy
           
(package private)  double squareflat
           
(package private)  PathIterator src
           
 
Fields inherited from interface java.awt.geom.PathIterator
SEG_CLOSE, SEG_CUBICTO, SEG_LINETO, SEG_MOVETO, SEG_QUADTO, WIND_EVEN_ODD, WIND_NON_ZERO
 
Constructor Summary
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
 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.
(package private)  void ensureHoldCapacity(int want)
           
 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.
private  void next(boolean doNext)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

GROW_SIZE

static final int GROW_SIZE
See Also:
Constant Field Values

src

PathIterator src

squareflat

double squareflat

limit

int limit

hold

double[] hold

curx

double curx

cury

double cury

movx

double movx

movy

double movy

holdType

int holdType

holdEnd

int holdEnd

holdIndex

int holdIndex

levels

int[] levels

levelIndex

int levelIndex

done

boolean done
Constructor Detail

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 Detail

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.

ensureHoldCapacity

void ensureHoldCapacity(int want)

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

next

private void next(boolean doNext)

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