org.geotools.geometry.jts

Class PolygonIterator

Object

AbstractLiteIterator

PolygonIterator

All Implemented Interfaces:

PathIterator

public final class PolygonIterator
extends AbstractLiteIterator

A path iterator for the LiteShape class, specialized to iterate over Polygon objects.

Author:

Andrea Aime, simone giannecchini

Field Summary

Fields inherited from class AbstractLiteIterator

dcoords

Fields inherited from interface PathIterator

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

Constructor Summary

Constructors

Constructor and Description
PolygonIterator(Polygon p, AffineTransform at) Creates a new PolygonIterator object.
PolygonIterator(Polygon p, AffineTransform at, boolean generalize) Creates a new PolygonIterator object.
PolygonIterator(Polygon p, AffineTransform at, boolean generalize, double maxDistance) Creates a new PolygonIterator object.

Method Summary

Modifier and Type	Method and Description
int	currentSegment(double[] coords) Returns the coordinates and type of the current path segment in the iteration.
double	getMaxDistance() Returns the distance limit for point skipping during distance based generalization
int	getWindingRule() Return 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.
void	setMaxDistance(double distance) Sets the distance limit for point skipping during distance based generalization
protected void	transform(double[] src, int index, double[] dest, int destIndex, int numPoints)

Methods inherited from class AbstractLiteIterator

currentSegment

Methods inherited from class Object

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

Constructor Detail

PolygonIterator

public PolygonIterator(Polygon p,
                       AffineTransform at)

Creates a new PolygonIterator object.

Parameters:

p - The polygon

at - The affine transform applied to coordinates during iteration

PolygonIterator

public PolygonIterator(Polygon p,
                       AffineTransform at,
                       boolean generalize)

Creates a new PolygonIterator object.

Parameters:

p - The polygon

at - The affine transform applied to coordinates during iteration

generalize - if true apply simple distance based generalization

PolygonIterator

public PolygonIterator(Polygon p,
                       AffineTransform at,
                       boolean generalize,
                       double maxDistance)

Creates a new PolygonIterator object.

Parameters:

p - The polygon

at - The affine transform applied to coordinates during iteration

generalize - if true apply simple distance based generalization

maxDistance - during iteration, a point will be skipped if it's distance from the previous is less than maxDistance

Method Detail

setMaxDistance

public void setMaxDistance(double distance)

Sets the distance limit for point skipping during distance based generalization

Parameters:

distance - the maximum distance for point skipping

getMaxDistance

public double getMaxDistance()

Returns the distance limit for point skipping during distance based generalization

Returns:

the maximum distance for distance based generalization

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, SEG_QUADTO, SEG_CUBICTO, 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 returns one point, SEG_QUADTO returns two points, SEG_CUBICTO returns 3 points and SEG_CLOSE does not return any points.

Parameters:

coords - an array that holds the data returned from this method

Returns:

the path-segment type of the current path segment.

See Also:

PathIterator.SEG_MOVETO, PathIterator.SEG_LINETO, PathIterator.SEG_QUADTO, PathIterator.SEG_CUBICTO, PathIterator.SEG_CLOSE

transform

protected void transform(double[] src,
                         int index,
                         double[] dest,
                         int destIndex,
                         int numPoints)

getWindingRule

public int getWindingRule()

Return the winding rule for determining the interior of the path.

Returns:

WIND_EVEN_ODD by default.

isDone

public boolean isDone()

Tests if the iteration is complete.

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.