java.awt.geom
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.

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