AbstractLine2D (java-geom 3.3.1 API)

java.lang.Object
- math.geom2d.curve.AbstractContinuousCurve2D
- - math.geom2d.curve.AbstractSmoothCurve2D
  - - math.geom2d.line.AbstractLine2D

All Implemented Interfaces:

Serializable, Cloneable, CirculinearContinuousCurve2D, CirculinearCurve2D, CirculinearElement2D, CirculinearShape2D, ContinuousCirculinearCurve2D, ContinuousCurve2D, Curve2D, SmoothCurve2D, ContinuousOrientedCurve2D, OrientedCurve2D, SmoothOrientedCurve2D, LinearShape2D, Shape2D

Direct Known Subclasses:

InvertedRay2D, LineArc2D, LineSegment2D, Ray2D, StraightLine2D
```
public abstract class AbstractLine2D
extends AbstractSmoothCurve2D
implements SmoothOrientedCurve2D, LinearShape2D, CirculinearElement2D
```
Base class for straight curves, such as straight lines, rays, or edges.

Internal representation of straight objects is parametric: (x0, y0) is a point in the object, and (dx, dy) is a direction vector of the line.

If the line is defined by two point, we can set (x0,y0) to the first point, and (dx,dy) to the vector (p1, p2).

Then, coordinates for a point (x,y) such as x=x0+t*dx and y=y0+t=dy, t between 0 and 1 give a point inside p1 and p2, t<0 give a point 'before' p1, and t>1 give a point 'after' p2, so it is convenient to easily manage edges, rays and straight lines.

See Also:
Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`protected double`	`dx` Direction vector of the line.
`protected double`	`dy` Direction vector of the line.
`protected double`	`x0` Coordinates of starting point of the line
`protected double`	`y0` Coordinates of starting point of the line

Fields inherited from interface math.geom2d.Shape2D
ACCURACY

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`AbstractLine2D(double x0, double y0, double dx, double dy)`
`protected`	`AbstractLine2D(LinearShape2D line)`
`protected`	`AbstractLine2D(Point2D point, Vector2D vector)`

Method Summary

Methods
Modifier and Type	Method and Description
`CurveSet2D<? extends AbstractLine2D>`	`clip(Box2D box)` When a curve is clipped, the result is a set of curves.
`abstract AbstractLine2D`	`clone()` Ensures public declaration of clone(), and ensures valid return type.
`boolean`	`contains(Point2D p)` Checks if the shape contains the given point.
`CirculinearDomain2D`	`getBuffer(double dist)` Computes the buffer of the shape, formed by the set of points located at a distance from the shape that is lower or equal to d.
`double[]`	`getCartesianEquation()` Returns the coefficient of the Cartesian representation of the line.
`Collection<? extends AbstractLine2D>`	`getContinuousCurves()` Returns the collection of continuous curves which constitute this curve.
`double`	`getCurvature(double t)` returns 0 as every straight object.
`double`	`getDistance(double x, double y)` Gets the distance of the StraightObject2d to the given point.
`double`	`getDistance(Point2D p)` Gets the distance of the StraightObject2d to the given point.
`double`	`getHorizontalAngle()` Gets Angle with axis (O,i), counted counter-clockwise.
`static Point2D`	`getIntersection(AbstractLine2D l1, AbstractLine2D l2)` Returns the unique intersection of two straight objects.
`Point2D`	`getIntersection(LinearShape2D line)` Returns the unique intersection with a linear shape.
`Collection<Point2D>`	`getIntersections(LinearShape2D line)` Returns the intersection points of the curve with the specified line.
`double`	`getLength()`
`double`	`getLength(double pos)`
`Point2D`	`getOrigin()` Returns a point in the linear shape.
`StraightLine2D`	`getParallel(Point2D point)` Create a straight line parallel to this object, and going through the given point.
`double[][]`	`getParametric()` Returns the matrix of parametric representation of the line.
`StraightLine2D`	`getPerpendicular(Point2D point)` Create a straight line perpendicular to this object, and going through the given point.
`double[]`	`getPolarCoefficients()` Returns polar coefficients.
`double`	`getPosition(double length)`
`double`	`getPosition(Point2D point)` Gets the position of the point on the line arc.
`double`	`getPositionOnLine(double x, double y)` Compute position on the line, that is the number t such that if the point belong to the line, it location is given by x=x0+tdx and y=y0+tdy.
`double`	`getPositionOnLine(Point2D point)`
`Point2D`	`getProjectedPoint(double x, double y)` Return the projection of point p on the line.
`Point2D`	`getProjectedPoint(Point2D p)` Return the projection of point p on the line.
`double`	`getSignedDistance(double x, double y)` Get the signed distance of the StraightObject2d to the given point.
`double`	`getSignedDistance(Point2D p)` Get the signed distance of the StraightObject2d to the given point.
`double[]`	`getSignedPolarCoefficients()` Returns the signed polar coefficients.
`Collection<? extends AbstractLine2D>`	`getSmoothPieces()` Return the intersection points of the curve with the specified line.
`AbstractLine2D`	`getSubCurve(double t0, double t1)` Returns a new AbstractLine2D, which is the portion of this AbstractLine2D delimited by parameters t0 and t1.
`StraightLine2D`	`getSupportingLine()`
`Point2D`	`getSymmetric(double x, double y)` Return the symmetric of point with coordinate (x, y) relative to this straight line.
`Point2D`	`getSymmetric(Point2D p)` Return the symmetric of point p relative to this straight line.
`Vector2D`	`getTangent(double t)`
`Vector2D`	`getVector()` Return one direction vector of the linear shape.
`double`	`getWindingAngle(Point2D point)` Return the angle portion that the curve turn around the given point.
`boolean`	`isClosed()` Always returns false, because we can not come back to starting point if we always go straight...
`static boolean`	`isColinear(AbstractLine2D line1, AbstractLine2D line2)` Test if the two linear objects are located on the same straight line.
`boolean`	`isColinear(LinearShape2D linear)`
`boolean`	`isEmpty()` Returns false, unless both dx and dy equal 0.
`boolean`	`isInside(Point2D p)` Returns true if the given point lies to the left of the line when traveling along the line in the direction given by its direction vector.
`static boolean`	`isParallel(AbstractLine2D line1, AbstractLine2D line2)` Test if the two linear objects are parallel.
`boolean`	`isParallel(LinearShape2D line)` Test if the this object is parallel to the given one.
`double`	`project(Point2D point)` Gets the position of the closest point on the line arc.
`protected boolean`	`supportContains(double x, double y)` Returns true if the point (x, y) lies on the line covering the object, with precision given by Shape2D.ACCURACY.
`abstract AbstractLine2D`	`transform(AffineTransform2D transform)` Transforms the curve by an affine transform.
`CirculinearElement2D`	`transform(CircleInversion2D inv)` Transforms the shape by a circle inversion.

Methods inherited from class math.geom2d.curve.AbstractSmoothCurve2D
getLeftTangent, getRightTangent, getSingularPoints, isSingular

Methods inherited from class math.geom2d.curve.AbstractContinuousCurve2D
draw, getAsAWTShape, getAsPolyline, getFirstPoint, getLastPoint, wrapCurve

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface math.geom2d.circulinear.CirculinearElement2D
getParallel, getReverseCurve

Methods inherited from interface math.geom2d.curve.ContinuousCurve2D
appendPath, getAsPolyline, getLeftTangent, getRightTangent

Methods inherited from interface math.geom2d.curve.Curve2D
draw, getAsAWTShape, getFirstPoint, getLastPoint, getPoint, getSingularPoints, getT0, getT1, isSingular

Methods inherited from interface math.geom2d.Shape2D
contains, getBoundingBox, isBounded

- Field Detail
  - x0
```
protected double x0
```
    Coordinates of starting point of the line
  - y0
```
protected double y0
```
    Coordinates of starting point of the line
  - dx
```
protected double dx
```
    Direction vector of the line. dx and dy should not be both zero.
  - dy
```
protected double dy
```
    Direction vector of the line. dx and dy should not be both zero.
- Constructor Detail
  - AbstractLine2D
```
protected AbstractLine2D(double x0,
              double y0,
              double dx,
              double dy)
```
  - AbstractLine2D
```
protected AbstractLine2D(Point2D point,
              Vector2D vector)
```
  - AbstractLine2D
```
protected AbstractLine2D(LinearShape2D line)
```
- Method Detail
  - getIntersection
```
public static final Point2D getIntersection(AbstractLine2D l1,
                      AbstractLine2D l2)
```
    Returns the unique intersection of two straight objects. If intersection doesn't exist (parallel lines), return null.
  - isColinear
```
public static final boolean isColinear(AbstractLine2D line1,
                 AbstractLine2D line2)
```
    Test if the two linear objects are located on the same straight line.
  - isParallel
```
public static final boolean isParallel(AbstractLine2D line1,
                 AbstractLine2D line2)
```
    Test if the two linear objects are parallel.
  - isColinear
```
public boolean isColinear(LinearShape2D linear)
```
  - isParallel
```
public boolean isParallel(LinearShape2D line)
```
    Test if the this object is parallel to the given one.
  - supportContains
```
protected boolean supportContains(double x,
                      double y)
```
    Returns true if the point (x, y) lies on the line covering the object, with precision given by Shape2D.ACCURACY.
  - getParametric
```
public double[][] getParametric()
```
    Returns the matrix of parametric representation of the line. Result has the form:
    [ x0 dx ]
    [ y0 dy ]
    It can be easily extended to higher dimensions and/or higher polynomial forms.
  - getCartesianEquation
```
public double[] getCartesianEquation()
```
    Returns the coefficient of the Cartesian representation of the line. Cartesian equation has the form: ax+by+c=0
    
    Returns:
    the array {a, b, c}.
  - getPolarCoefficients
```
public double[] getPolarCoefficients()
```
    Returns polar coefficients.
    
    Returns:
    an array of 2 elements, the first one is the distance to the origin, the second one is the angle with horizontal, between 0 and 2*PI.
  - getSignedPolarCoefficients
```
public double[] getSignedPolarCoefficients()
```
    Returns the signed polar coefficients. Distance to origin can be negative: this allows representation of directed lines.
    
    Returns:
    an array of 2 elements, the first one is the signed distance to the origin, the second one is the angle with horizontal, between 0 and 2*PI.
  - getPositionOnLine
```
public double getPositionOnLine(Point2D point)
```
  - getPositionOnLine
```
public double getPositionOnLine(double x,
                       double y)
```
    Compute position on the line, that is the number t such that if the point belong to the line, it location is given by x=x0+t*dx and y=y0+t*dy.
    If the point does not belong to the line, the method returns the position of its projection on the line.
  - getProjectedPoint
```
public Point2D getProjectedPoint(Point2D p)
```
    Return the projection of point p on the line. The returned point can be used to compute distance from point to line.
    
    Parameters:
    p - a point outside the line (if point p lies on the line, it is returned)
    
    Returns:
    the projection of the point p on the line
  - getProjectedPoint
```
public Point2D getProjectedPoint(double x,
                        double y)
```
    Return the projection of point p on the line. The returned point can be used to compute distance from point to line.
    
    Parameters:
    x - : coordinate x of point to be projected
    y - : coordinate y of point to be projected
    
    Returns:
    the projection of the point p on the line
  - getSymmetric
```
public Point2D getSymmetric(Point2D p)
```
    Return the symmetric of point p relative to this straight line.
    
    Parameters:
    p - a point outside the line (if point p lies on the line, it is returned)
    
    Returns:
    the projection of the point p on the line
  - getSymmetric
```
public Point2D getSymmetric(double x,
                   double y)
```
    Return the symmetric of point with coordinate (x, y) relative to this straight line.
    
    Parameters:
    x - : coordinate x of point to be projected
    y - : coordinate y of point to be projected
    
    Returns:
    the projection of the point (x,y) on the line
  - getParallel
```
public StraightLine2D getParallel(Point2D point)
```
    Create a straight line parallel to this object, and going through the given point.
    
    Parameters:
    point - the point to go through
    
    Returns:
    the parallel through the point
  - getPerpendicular
```
public StraightLine2D getPerpendicular(Point2D point)
```
    Create a straight line perpendicular to this object, and going through the given point.
    
    Parameters:
    point - the point to go through
    
    Returns:
    the perpendicular through the point
  - getOrigin
```
public Point2D getOrigin()
```
    Description copied from interface: LinearShape2D
    
    Returns a point in the linear shape.
    
    Specified by:
    
    getOrigin in interface LinearShape2D
    
    Returns:
    a point in the linear shape.
  - getVector
```
public Vector2D getVector()
```
    Description copied from interface: LinearShape2D
    
    Return one direction vector of the linear shape.
    
    Specified by:
    
    getVector in interface LinearShape2D
    
    Returns:
    a direction vector
  - getHorizontalAngle
```
public double getHorizontalAngle()
```
    Gets Angle with axis (O,i), counted counter-clockwise. Result is given between 0 and 2*pi.
    
    Specified by:
    
    getHorizontalAngle in interface LinearShape2D
  - getIntersection
```
public Point2D getIntersection(LinearShape2D line)
```
    Returns the unique intersection with a linear shape. If the intersection doesn't exist (parallel lines), returns null.
    
    Specified by:
    
    getIntersection in interface LinearShape2D
  - getSupportingLine
```
public StraightLine2D getSupportingLine()
```
    Specified by:
    
    getSupportingLine in interface LinearShape2D
  - getBuffer
```
public CirculinearDomain2D getBuffer(double dist)
```
    Description copied from interface: CirculinearShape2D
    
    Computes the buffer of the shape, formed by the set of points located at a distance from the shape that is lower or equal to d.
    
    Specified by:
    
    getBuffer in interface CirculinearShape2D
    
    Parameters:
    dist - the maximal distance between a point of the buffer and the shape
    
    Returns:
    the buffer of the shape
  - getLength
```
public double getLength()
```
    Specified by:
    
    getLength in interface CirculinearCurve2D
    
    Returns:
    the length of the curve
  - getLength
```
public double getLength(double pos)
```
    Specified by:
    
    getLength in interface CirculinearCurve2D
    
    Returns:
    the length from the beginning to the position given by pos
  - getPosition
```
public double getPosition(double length)
```
    Specified by:
    
    getPosition in interface CirculinearCurve2D
    
    Returns:
    the position located at distance 'length' from the origin
  - transform
```
public CirculinearElement2D 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 CirculinearElement2D
    
    Specified by:
    
    transform in interface CirculinearShape2D
    
    Specified by:
    
    transform in interface ContinuousCirculinearCurve2D
    
    Parameters:
    inv - the circle inversion
    
    Returns:
    the transformed shape
  - getWindingAngle
```
public double getWindingAngle(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:
    
    getWindingAngle in interface OrientedCurve2D
    
    Parameters:
    point - a point of the plane
    
    Returns:
    a signed angle
  - getSignedDistance
```
public double getSignedDistance(Point2D p)
```
    Get the signed distance of the StraightObject2d to the given point. The signed distance is positive if point lies 'to the right' of the line, when moving in the direction given by direction vector. This method is not designed to be used directly, because AbstractLine2D is an abstract class, but it can be used by subclasses to help computations.
    
    Specified by:
    
    getSignedDistance in interface OrientedCurve2D
    
    Parameters:
    p - a point of the plane
    
    Returns:
    the signed distance to the curve
  - getSignedDistance
```
public double getSignedDistance(double x,
                       double y)
```
    Get the signed distance of the StraightObject2d to the given point. The signed distance is positive if point lies 'to the right' of the line, when moving in the direction given by direction vector. This method is not designed to be used directly, because AbstractLine2D is an abstract class, but it can be used by subclasses to help computations.
    
    Specified by:
    
    getSignedDistance in interface OrientedCurve2D
    
    Parameters:
    x - x-coord of a point
    y - y-coord of a point
    
    Returns:
    the signed distance of the point (x,y) to the curve
  - isInside
```
public boolean isInside(Point2D p)
```
    Returns true if the given point lies to the left of the line when traveling along the line in the direction given by its direction vector.
    
    Specified by:
    
    isInside in interface OrientedCurve2D
    
    Parameters:
    p - the point to test
    
    Returns:
    true if point p lies on the 'left' of the line.
  - getTangent
```
public Vector2D getTangent(double t)
```
    Specified by:
    
    getTangent in interface SmoothCurve2D
  - getCurvature
```
public double getCurvature(double t)
```
    returns 0 as every straight object.
    
    Specified by:
    
    getCurvature in interface SmoothCurve2D
  - isClosed
```
public boolean isClosed()
```
    Always returns false, because we can not come back to starting point if we always go straight...
    
    Specified by:
    
    isClosed in interface ContinuousCurve2D
  - getSmoothPieces
```
public Collection<? extends AbstractLine2D> getSmoothPieces()
```
    Return the intersection points of the curve with the specified line. The length of the result array is the number of intersection points.
    
    Specified by:
    
    getSmoothPieces in interface CirculinearContinuousCurve2D
    
    Specified by:
    
    getSmoothPieces in interface ContinuousCirculinearCurve2D
    
    Specified by:
    
    getSmoothPieces in interface ContinuousCurve2D
    
    Overrides:
    
    getSmoothPieces in class AbstractSmoothCurve2D
  - getIntersections
```
public Collection<Point2D> getIntersections(LinearShape2D line)
```
    Description copied from interface: Curve2D
    
    Returns the intersection points of the curve with the specified line. The length of the result array is the number of intersection points.
    
    Specified by:
    
    getIntersections in interface Curve2D
  - getPosition
```
public double getPosition(Point2D point)
```
    Gets the position of the point on the line arc. If point belongs to the line, this position is defined by the ratio:
    t = (xp - x0)/dx <\code>, or equivalently:
    t = (yp - y0)/dy <\code>.
    If point does not belong to edge, returns Double.NaN.
    Specified by: getPosition in interface Curve2D Parameters: point - a point belonging to the curve Returns: the position of the point on the curve
  project public double project(Point2D point) Gets the position of the closest point on the line arc. If point belongs to the line, this position is defined by the ratio: t = (xp - x0)/dx <\code>, or equivalently: t = (yp - y0)/dy <\code>. If point does not belong to edge, returns t0, or t1, depending on which one is the closest. Specified by: project in interface Curve2D Parameters: point - a point to project Returns: the position of the closest orthogonal projection getSubCurve public AbstractLine2D getSubCurve(double t0, double t1) Returns a new AbstractLine2D, which is the portion of this AbstractLine2D delimited by parameters t0 and t1. Casts the result to StraightLine2D, Ray2D or LineSegment2D when appropriate. Specified by: getSubCurve in interface CirculinearContinuousCurve2D Specified by: getSubCurve in interface CirculinearCurve2D Specified by: getSubCurve in interface CirculinearElement2D Specified by: getSubCurve in interface ContinuousCirculinearCurve2D Specified by: getSubCurve in interface ContinuousCurve2D Specified by: getSubCurve in interface Curve2D Specified by: getSubCurve in interface SmoothCurve2D Specified by: getSubCurve in interface ContinuousOrientedCurve2D Specified by: getSubCurve in interface SmoothOrientedCurve2D 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. getContinuousCurves public Collection<? extends AbstractLine2D> getContinuousCurves() Description copied from interface: Curve2D Returns the collection of continuous curves which constitute this curve. Specified by: getContinuousCurves in interface CirculinearCurve2D Specified by: getContinuousCurves in interface Curve2D Overrides: getContinuousCurves in class AbstractContinuousCurve2D Returns: a collection of continuous curves. getDistance public double getDistance(Point2D p) Gets the distance of the StraightObject2d to the given point. This method is not designed to be used directly, because AbstractLine2D is an abstract class, but it can be called by subclasses to help computations. Specified by: getDistance in interface Shape2D getDistance public double getDistance(double x, double y) Gets the distance of the StraightObject2d to the given point. This method is not designed to be used directly, because AbstractLine2D is an abstract class, but it can be used by subclasses to help computations. Specified by: getDistance in interface Shape2D Parameters: x - x-coordinate of the point y - y-coordinate of the point Returns: distance between this object and the point (x,y) contains public boolean contains(Point2D p) Description copied from interface: Shape2D Checks if the shape contains the given point. Specified by: contains in interface Shape2D isEmpty public boolean isEmpty() Returns false, unless both dx and dy equal 0. Specified by: isEmpty in interface Shape2D Returns: true if the shape does not contain any point. transform public abstract AbstractLine2D transform(AffineTransform2D transform) Description copied from interface: Curve2D Transforms the curve by an affine transform. The result is an instance of Curve2D. Specified by: transform in interface ContinuousCurve2D Specified by: transform in interface Curve2D Specified by: transform in interface SmoothCurve2D Specified by: transform in interface ContinuousOrientedCurve2D Specified by: transform in interface OrientedCurve2D Specified by: transform in interface SmoothOrientedCurve2D Specified by: transform in interface LinearShape2D Specified by: transform in interface Shape2D Parameters: transform - an affine transform Returns: the transformed shape clip public CurveSet2D<? extends AbstractLine2D> clip(Box2D box) Description copied from interface: Curve2D When a curve is clipped, the result is a set of curves. Specified by: clip in interface CirculinearContinuousCurve2D Specified by: clip in interface CirculinearCurve2D Specified by: clip in interface CirculinearElement2D Specified by: clip in interface ContinuousCirculinearCurve2D Specified by: clip in interface ContinuousCurve2D Specified by: clip in interface Curve2D Specified by: clip in interface SmoothCurve2D Specified by: clip in interface ContinuousOrientedCurve2D Specified by: clip in interface OrientedCurve2D Specified by: clip in interface SmoothOrientedCurve2D Specified by: clip in interface Shape2D Parameters: box - the clipping box Returns: the clipped shape clone public abstract AbstractLine2D clone() Ensures public declaration of clone(), and ensures valid return type. Specified by: clone in interface Curve2D Specified by: clone in class AbstractSmoothCurve2D Returns: the cloned curve

Class AbstractLine2D

Field Summary

Fields inherited from interface math.geom2d.Shape2D

Constructor Summary

Method Summary

Methods inherited from class math.geom2d.curve.AbstractSmoothCurve2D

Methods inherited from class math.geom2d.curve.AbstractContinuousCurve2D

Methods inherited from class java.lang.Object

Methods inherited from interface math.geom2d.circulinear.CirculinearElement2D

Methods inherited from interface math.geom2d.curve.ContinuousCurve2D

Methods inherited from interface math.geom2d.curve.Curve2D

Methods inherited from interface math.geom2d.Shape2D

Field Detail

x0

y0

dx

dy

Constructor Detail

AbstractLine2D

AbstractLine2D

AbstractLine2D

Method Detail

getIntersection

isColinear

isParallel

isColinear

isParallel

supportContains

getParametric

getCartesianEquation

getPolarCoefficients

getSignedPolarCoefficients

getPositionOnLine

getPositionOnLine

getProjectedPoint

getProjectedPoint

getSymmetric

getSymmetric

getParallel

getPerpendicular

getOrigin

getVector

getHorizontalAngle

getIntersection

getSupportingLine

getBuffer

getLength

getLength

getPosition

transform

getWindingAngle

getSignedDistance

getSignedDistance

isInside

getTangent

getCurvature

isClosed

getSmoothPieces

getIntersections

getPosition

project

getSubCurve

getContinuousCurves

getDistance

getDistance

contains

isEmpty

transform

clip

clone