math.geom2d.polygon
Class Polyline2D

java.lang.Object
  math.geom2d.curve.AbstractContinuousCurve2D
      math.geom2d.polygon.LinearCurve2D
          math.geom2d.polygon.Polyline2D

All Implemented Interfaces:

java.lang.Cloneable, CirculinearContinuousCurve2D, CirculinearCurve2D, CirculinearShape2D, ContinuousCurve2D, Curve2D, ContinuousOrientedCurve2D, OrientedCurve2D, GeometricObject2D, Shape2D

public class Polyline2D
extends LinearCurve2D
implements CirculinearContinuousCurve2D, java.lang.Cloneable

A polyline is a continuous curve where each piece of the curve is a LineSegment2D.

Author:

dlegland

Field Summary

Fields inherited from interface math.geom2d.Shape2D

ACCURACY

Constructor Summary

Polyline2D()

Polyline2D(java.util.Collection<? extends Point2D> vertices)

Polyline2D(double[] xcoords, double[] ycoords)

Polyline2D(int nVertices)
Creates a new polyline by allocating enough memory for the specified number of vertices.

Polyline2D(Point2D... vertices)

Polyline2D(Point2D initialPoint)

Method Summary

boolean	almostEquals(GeometricObject2D obj, double eps) Checks if the two objects are similar up to a given threshold value.
java.awt.geom.GeneralPath	appendPath(java.awt.geom.GeneralPath path) Append the path of the curve to the given path.
java.awt.geom.GeneralPath	asGeneralPath() Returns a general path iterator.
Polyline2D	clone() Overrides Object declaration to ensure Curve2D implementation are cloned as Curve2D.
java.util.Collection<? extends Polyline2D>	continuousCurves() Returns the collection of continuous curves which constitute this curve.
static Polyline2D	create(java.util.Collection<? extends Point2D> points) Static factory for creating a new Polyline2D from a collection of points.
static Polyline2D	create(Point2D... points) Static factory for creating a new Polyline2D from an array of points.
LineSegment2D	edge(int index) Returns the i-th edge of this linear curve.
int	edgeNumber() Returns the number of edges of this linear curve.
java.util.Collection<LineSegment2D>	edges() Returns an array of LineSegment2D.
boolean	equals(java.lang.Object object)
double	getT1() Deprecated. replaced by t1() (since 0.11.1).
boolean	isClosed() Returns false, as Polyline2D is open by definition.
boolean	isInside(Point2D pt) Returns true if the point is 'inside' the domain bounded by the curve.
LineSegment2D	lastEdge()
Point2D	lastPoint() Returns the last point of this polyline, or null if the polyline does not contain any point.
Point2D	point(double t) Returns the point located at the given position on the curve.
Polyline2D	reverse() Returns the polyline with same points considered in reverse order.
Polyline2D	subCurve(double t0, double t1) Return an instance of Polyline2D.
double	t1() Returns the number of points in the polyline, minus one.
Polyline2D	transform(AffineTransform2D trans) Transforms the shape by an affine transform.
CirculinearContinuousCurve2D	transform(CircleInversion2D inv) Transforms the shape by a circle inversion.
double	windingAngle(Point2D point) Return the angle portion that the curve turn around the given point.

Methods inherited from class math.geom2d.polygon.LinearCurve2D

addVertex, boundingBox, buffer, clearVertices, clip, closestVertexIndex, contains, contains, curvature, distance, distance, draw, firstEdge, firstPoint, getT0, insertVertex, intersections, isBounded, isEmpty, isSingular, leftTangent, length, length, parallel, position, position, project, removeVertex, removeVertex, rightTangent, setVertex, signedDistance, signedDistance, singularPoints, smoothPieces, t0, vertex, vertexArray, vertexIterator, vertexNumber, vertices

Methods inherited from class math.geom2d.curve.AbstractContinuousCurve2D

asAwtShape, asPolyline

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface math.geom2d.circulinear.CirculinearContinuousCurve2D

clip, parallel, smoothPieces

Methods inherited from interface math.geom2d.circulinear.CirculinearCurve2D

length, length, position

Methods inherited from interface math.geom2d.circulinear.CirculinearShape2D

buffer

Methods inherited from interface math.geom2d.curve.ContinuousCurve2D

asPolyline, curvature, leftTangent, rightTangent

Methods inherited from interface math.geom2d.domain.OrientedCurve2D

signedDistance, signedDistance

Methods inherited from interface math.geom2d.curve.Curve2D

asAwtShape, draw, firstPoint, getT0, intersections, isSingular, position, project, singularPoints, t0, vertices

Methods inherited from interface math.geom2d.Shape2D

boundingBox, contains, contains, distance, distance, isBounded, isEmpty

Constructor Detail

Polyline2D

public Polyline2D()

Polyline2D

public Polyline2D(int nVertices)

Creates a new polyline by allocating enough memory for the specified number of vertices.

Parameters:

nVertices -

Polyline2D

public Polyline2D(Point2D initialPoint)

Polyline2D

public Polyline2D(Point2D... vertices)

Polyline2D

public Polyline2D(java.util.Collection<? extends Point2D> vertices)

Polyline2D

public Polyline2D(double[] xcoords,
                  double[] ycoords)

Method Detail

create

public static Polyline2D create(java.util.Collection<? extends Point2D> points)

Static factory for creating a new Polyline2D from a collection of points.

Since:

0.8.1

create

public static Polyline2D create(Point2D... points)

Static factory for creating a new Polyline2D from an array of points.

Since:

0.8.1

edges

public java.util.Collection<LineSegment2D> edges()

Returns an array of LineSegment2D. The number of edges is the number of vertices minus one.

Specified by:

edges in class LinearCurve2D

Returns:

the edges of the polyline

edgeNumber

public int edgeNumber()

Description copied from class: LinearCurve2D

Returns the number of edges of this linear curve.

Specified by:

edgeNumber in class LinearCurve2D

edge

public LineSegment2D edge(int index)

Description copied from class: LinearCurve2D

Returns the i-th edge of this linear curve.

Specified by:

edge in class LinearCurve2D

lastEdge

public LineSegment2D lastEdge()

Specified by:

lastEdge in class LinearCurve2D

transform

public CirculinearContinuousCurve2D transform(CircleInversion2D inv)

Description copied from interface: CirculinearShape2D

Transforms the shape by a circle inversion. The result is still an instance a CirculinearShape2D.

Specified by:

transform in interface CirculinearContinuousCurve2D

Specified by:

transform in interface CirculinearCurve2D

Specified by:

transform in interface CirculinearShape2D

Parameters:

inv - the circle inversion

Returns:

the transformed shape

windingAngle

public double windingAngle(Point2D point)

Description copied from interface: OrientedCurve2D

Return the angle portion that the curve turn around the given point. Result is a signed angle.

Specified by:

windingAngle in interface OrientedCurve2D

Parameters:

point - a point of the plane

Returns:

a signed angle

isInside

public boolean isInside(Point2D pt)

Description copied from interface: OrientedCurve2D

Returns true if the point is 'inside' the domain bounded by the curve.

Specified by:

isInside in interface OrientedCurve2D

Parameters:

pt - a point in the plane

Returns:

true if the point is on the left side of the curve.

isClosed

public boolean isClosed()

Returns false, as Polyline2D is open by definition.

Specified by:

isClosed in interface ContinuousCurve2D

point

public Point2D point(double t)

Description copied from interface: Curve2D

Returns the point located at the given position on the curve. If the parameter lies outside the definition range, the parameter corresponding to the closest bound is used instead. This method can be used to draw an approximated outline of a curve, by selecting multiple values for t and drawing lines between them.

Specified by:

point in interface Curve2D

t1

public double t1()

Returns the number of points in the polyline, minus one.

Specified by:

t1 in interface Curve2D

getT1

@Deprecated
public double getT1()

Deprecated. replaced by t1() (since 0.11.1).

Specified by:

getT1 in interface Curve2D

lastPoint

public Point2D lastPoint()

Returns the last point of this polyline, or null if the polyline does not contain any point.

Specified by:

lastPoint in interface Curve2D

Overrides:

lastPoint in class AbstractContinuousCurve2D

Returns:

the last point of the curve.

See Also:

Curve2D.t1(), Curve2D.point(double)

reverse

public Polyline2D reverse()

Returns the polyline with same points considered in reverse order. Reversed polyline keep same references as original polyline.

Specified by:

reverse in interface CirculinearContinuousCurve2D

Specified by:

reverse in interface CirculinearCurve2D

Specified by:

reverse in interface ContinuousCurve2D

Specified by:

reverse in interface Curve2D

Specified by:

reverse in interface ContinuousOrientedCurve2D

Specified by:

reverse in interface OrientedCurve2D

continuousCurves

public java.util.Collection<? extends Polyline2D> continuousCurves()

Description copied from interface: Curve2D

Returns the collection of continuous curves which constitute this curve.

Specified by:

continuousCurves in interface CirculinearCurve2D

Specified by:

continuousCurves in interface Curve2D

Overrides:

continuousCurves in class LinearCurve2D

Returns:

a collection of continuous curves.

subCurve

public Polyline2D subCurve(double t0,
                           double t1)

Return an instance of Polyline2D. If t1 is lower than t0, return an instance of Polyline2D with zero points.

Specified by:

subCurve in interface CirculinearContinuousCurve2D

Specified by:

subCurve in interface CirculinearCurve2D

Specified by:

subCurve in interface ContinuousCurve2D

Specified by:

subCurve in interface Curve2D

Specified by:

subCurve in interface ContinuousOrientedCurve2D

Parameters:

t0 - position of the start of the sub-curve

t1 - position of the end of the sub-curve

Returns:

the portion of original curve comprised between t0 and t1.

transform

public Polyline2D transform(AffineTransform2D trans)

Description copied from interface: Shape2D

Transforms the shape by an affine transform. Subclasses may override the type of returned shape.

Specified by:

transform in interface ContinuousCurve2D

Specified by:

transform in interface Curve2D

Specified by:

transform in interface ContinuousOrientedCurve2D

Specified by:

transform in interface OrientedCurve2D

Specified by:

transform in interface Shape2D

Parameters:

trans - an affine transform

Returns:

the transformed shape

appendPath

public java.awt.geom.GeneralPath appendPath(java.awt.geom.GeneralPath path)

Description copied from interface: ContinuousCurve2D

Append the path of the curve to the given path.

Specified by:

appendPath in interface ContinuousCurve2D

Parameters:

path - a path to modify

Returns:

the modified path

asGeneralPath

public java.awt.geom.GeneralPath asGeneralPath()

Returns a general path iterator.

Overrides:

asGeneralPath in class LinearCurve2D

almostEquals

public boolean almostEquals(GeometricObject2D obj,
                            double eps)

Description copied from interface: GeometricObject2D

Checks if the two objects are similar up to a given threshold value. This method can be used to compare the results of geometric computations, that introduce errors due to numerical computations.

Specified by:

almostEquals in interface GeometricObject2D

Parameters:

obj - the object to compare

eps - a threshold value, for example the minimal coordinate difference

Returns:

true if both object have the same value up to the threshold

equals

public boolean equals(java.lang.Object object)

Overrides:

equals in class java.lang.Object

clone

public Polyline2D clone()

Description copied from interface: Curve2D

Overrides Object declaration to ensure Curve2D implementation are cloned as Curve2D.

Specified by:

clone in interface Curve2D

Specified by:

clone in class AbstractContinuousCurve2D

Returns:

the cloned curve