Package org.djutils.draw.point

Class Point2d

java.lang.Object
org.djutils.draw.point.Point2d
All Implemented Interfaces:
Serializable, Drawable<Point2d>, Drawable2d, Point<Point2d>
Direct Known Subclasses:
DirectedPoint2d
public class Point2d extends Object implements Drawable2d, Point<Point2d>
A Point2d is an immutable Point with an x and y coordinate, stored with double precision. It differs from many Point implementations by being immutable.

Copyright (c) 2020-2024 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See DJUTILS License.

Author:
Alexander Verbraeck, Peter Knoppers
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    final double
    x
    The x-coordinate.
    final double
    y
    The y-coordinate.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Point2d(double[] xy)
    Create a new Point2d from a x and y coordinates provided as values in a double array.
    Point2d(double x, double y)
    Create a new Point2d from x and y coordinates provided as double arguments.
    Point2d(Point2D point)
    Create an new Point2d from x and y obtained from a java.awt.geom.Point2D.

  • Method Summary

    Modifier and Type
    Method
    Description
    Point2d
    abs()
    Return a new Point with absolute coordinate values.
    static final List<Point2d>
    circleIntersections(Point2d center1, double radius1, Point2d center2, double radius2)
    Return the zero, one or two intersections between two circles.
    final Point2d
    closestPointOnLine(double p1X, double p1Y, double p2X, double p2Y)
    Project a point on a line.
    Point2d
    closestPointOnLine(double p1X, double p1Y, double p2X, double p2Y, Boolean lowLimitHandling, Boolean highLimitHandling)
    Compute the closest point on a line with optional limiting of the result on either end.
    Point2d
    closestPointOnLine(Point2d linePoint1, Point2d linePoint2)
    Project a point on a line.
    final Point2d
    closestPointOnSegment(double p1X, double p1Y, double p2X, double p2Y)
    Project a point on a line segment.
    Point2d
    closestPointOnSegment(Point2d segmentPoint1, Point2d segmentPoint2)
    Project a point on a line segment.
    double
    directionTo(Point2d otherPoint)
    Return the direction to another Point2d.
    double
    distance(Point2d otherPoint)
    Return the distance to another point.
    double
    distanceSquared(Point2d otherPoint)
    Return the squared distance between this point and the provided point.
    boolean
    epsilonEquals(Point2d otherPoint, double epsilon)
    A comparison with another point that returns true of each of the coordinates is less than epsilon apart.
    boolean
    equals(Object obj)
     
    double
    fractionalPositionOnLine(double p1X, double p1Y, double p2X, double p2Y, Boolean lowLimitHandling, Boolean highLimitHandling)
    Compute the fractional position of the closest point on a line with optional limiting of the result on either end.
    Bounds2d
    getBounds()
    Retrieve the bounding rectangle of the object.
    Iterator<? extends Point2d>
    getPoints()
    Retrieve, or generate all points that make up the object.
    final double
    getX()
    Return the x-coordinate.
    final double
    getY()
    Return the y-coordinate.
    int
    hashCode()
     
    Point2d
    interpolate(Point2d otherPoint, double fraction)
    Interpolate towards another Point with a fraction.
    static Point2d
    intersectionOfLines(double line1P1X, double line1P1Y, double line1P2X, double line1P2Y, boolean lowLimitLine1, boolean highLimitLine1, double line2P1X, double line2P1Y, double line2P2X, double line2P2Y, boolean lowLimitLine2, boolean highLimitLine2)
    Compute the 2D intersection of two lines.
    static Point2d
    intersectionOfLines(double l1P1X, double l1P1Y, double l1P2X, double l1P2Y, double l2P1X, double l2P1Y, double l2P2X, double l2P2Y)
    Compute the 2D intersection of two lines.
    static Point2d
    intersectionOfLines(Point2d line1P1, Point2d line1P2, Point2d line2P1, Point2d line2P2)
    Compute the 2D intersection of two lines.
    static Point2d
    intersectionOfLineSegments(double line1P1X, double line1P1Y, double line1P2X, double line1P2Y, double line2P1X, double line2P1Y, double line2P2X, double line2P2Y)
    Compute the 2D intersection of two line segments.
    static Point2d
    intersectionOfLineSegments(LineSegment2d segment1, LineSegment2d segment2)
    Compute the 2D intersection of two line segments.
    static Point2d
    intersectionOfLineSegments(Point2d line1P1, Point2d line1P2, Point2d line2P1, Point2d line2P2)
    Compute the 2D intersection of two line segments.
    Point2d
    neg()
    Return a new Point with negated coordinate values.
    Point2d
    normalize()
    Return a new Point with a distance of 1 to the origin.
    Point2d
    scale(double factor)
    Return a new Point with the coordinates of this point scaled by the provided factor.
    int
    size()
    Retrieve the number of points that make up the object.
    Point2D
    toPoint2D()
    Return the coordinates as a java.awt.geom.Point2D.Double object.
    String
    toString()
    Produce a string describing the Drawable using default conversion for the (double) coordinate values.
    String
    toString(String doubleFormat, boolean doNotIncludeClassName)
    Produce a String describing the Drawable.
    Point2d
    translate(double dx, double dy)
    Return a new Point2d with a translation by the provided dx and dy.
    Point3d
    translate(double dx, double dy, double dz)
    Return a new Point3d with a translation by the provided dx, dy and dz.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

    Methods inherited from interface org.djutils.draw.Drawable

    getPointList, toString, toString

    Methods inherited from interface org.djutils.draw.Drawable2d

    getDimensions

  • Field Details

    • x

      public final double x
      The x-coordinate.

    • y

      public final double y
      The y-coordinate.

  • Constructor Details

  • Method Details

    • getX

      public final double getX()
      Description copied from interface: Point
      Return the x-coordinate. When the point is not in Cartesian space, a calculation to Cartesian space has to be made.
      Specified by:
      getX in interface Point<Point2d>
      Returns:
      double; the x-coordinate

    • getY

      public final double getY()
      Description copied from interface: Point
      Return the y-coordinate. When the point is not in Cartesian space, a calculation to Cartesian space has to be made.
      Specified by:
      getY in interface Point<Point2d>
      Returns:
      double; the y-coordinate

    • distance

      public double distance(Point2d otherPoint)
      Description copied from interface: Point
      Return the distance to another point.
      Specified by:
      distance in interface Point<Point2d>
      Parameters:
      otherPoint - P; P the other point
      Returns:
      double; the distance (2d or 3d as applicable) to the other point

    • distanceSquared

      public double distanceSquared(Point2d otherPoint) throws NullPointerException
      Description copied from interface: Point
      Return the squared distance between this point and the provided point.
      Specified by:
      distanceSquared in interface Point<Point2d>
      Parameters:
      otherPoint - P; the other point
      Returns:
      double; the squared distance between this point and the other point
      Throws:
      NullPointerException - when otherPoint is null

    • size

      public int size()
      Description copied from interface: Drawable
      Retrieve the number of points that make up the object.
      Specified by:
      size in interface Drawable<Point2d>
      Returns:
      int; the number of points that make up the object

    • getPoints

      public Iterator<? extends Point2d> getPoints()
      Description copied from interface: Drawable
      Retrieve, or generate all points that make up the object.
      Specified by:
      getPoints in interface Drawable<Point2d>
      Returns:
      Iterable<Point2d>; an iterator that generates all points that make up the object

    • translate

      public Point2d translate(double dx, double dy)
      Return a new Point2d with a translation by the provided dx and dy.
      Parameters:
      dx - double; the x translation
      dy - double; the y translation
      Returns:
      P; a new point with the translated coordinates
      Throws:
      IllegalArgumentException - when dx, or dy is NaN

    • translate

      public Point3d translate(double dx, double dy, double dz)
      Return a new Point3d with a translation by the provided dx, dy and dz. If this is an OrientedPoint2d, then the result is an OrientedPoint3d with rotX copied from this and rotY and rotZ are set to 0.0.
      Parameters:
      dx - double; the x translation
      dy - double; the y translation
      dz - double; the z translation
      Returns:
      Point2d; a new point with the translated coordinates
      Throws:
      IllegalArgumentException - when dx, dy, or dz is NaN

    • scale

      public Point2d scale(double factor)
      Description copied from interface: Point
      Return a new Point with the coordinates of this point scaled by the provided factor.
      Specified by:
      scale in interface Point<Point2d>
      Parameters:
      factor - double; the scale factor
      Returns:
      Point; a new point with the coordinates of this point scaled by the provided factor

    • neg

      public Point2d neg()
      Description copied from interface: Point
      Return a new Point with negated coordinate values. If this is a DirectedPoint, dirY and dirZ are negated.
      Specified by:
      neg in interface Point<Point2d>
      Returns:
      Point; a new point with negated coordinate values

    • abs

      public Point2d abs()
      Description copied from interface: Point
      Return a new Point with absolute coordinate values. If this is a DirectedPoint, dirY and dirZ are copied unchanged.
      Specified by:
      abs in interface Point<Point2d>
      Returns:
      Point; a new point with absolute coordinate values

    • normalize

      public Point2d normalize() throws DrawRuntimeException
      Description copied from interface: Point
      Return a new Point with a distance of 1 to the origin.
      Specified by:
      normalize in interface Point<Point2d>
      Returns:
      Point; the normalized point
      Throws:
      DrawRuntimeException - when point is the origin, and no length can be established for scaling

    • interpolate

      public Point2d interpolate(Point2d otherPoint, double fraction)
      Description copied from interface: Point
      Interpolate towards another Point with a fraction. It is allowed for fraction to be less than zero or larger than 1. In that case the interpolation turns into an extrapolation.
      Specified by:
      interpolate in interface Point<Point2d>
      Parameters:
      otherPoint - P; the other point
      fraction - double; the factor for interpolation towards the other point. When <code>fraction</code> is between 0 and 1, it is an interpolation, otherwise an extrapolation. If fraction is 0; this Point is returned; if fraction is 1, the other point is returned
      Returns:
      P; the point that is fraction away on the line between this point and the other point

    • epsilonEquals

      public boolean epsilonEquals(Point2d otherPoint, double epsilon)
      Description copied from interface: Point
      A comparison with another point that returns true of each of the coordinates is less than epsilon apart.
      Specified by:
      epsilonEquals in interface Point<Point2d>
      Parameters:
      otherPoint - P; the point to compare with
      epsilon - double; the upper bound of difference for one of the coordinates
      Returns:
      boolean; true if both x, y and z (if a Point3d) are less than epsilon apart, otherwise false

    • getBounds

      public Bounds2d getBounds()
      Description copied from interface: Drawable2d
      Retrieve the bounding rectangle of the object.
      Specified by:
      getBounds in interface Drawable2d
      Returns:
      Bounds2d; the bounding box of the object

    • intersectionOfLines

      public static Point2d intersectionOfLines(double line1P1X, double line1P1Y, double line1P2X, double line1P2Y, boolean lowLimitLine1, boolean highLimitLine1, double line2P1X, double line2P1Y, double line2P2X, double line2P2Y, boolean lowLimitLine2, boolean highLimitLine2) throws DrawRuntimeException
      Compute the 2D intersection of two lines. Both lines are defined by two points (that should be distinct).
      Parameters:
      line1P1X - double; x-coordinate of start point of line 1
      line1P1Y - double; y-coordinate of start point of line 1
      line1P2X - double; x-coordinate of end point of line 1
      line1P2Y - double; y-coordinate of end point of line 1
      lowLimitLine1 - boolean; if true; the intersection may not lie before the start point of line 1
      highLimitLine1 - boolean; if true; the intersection may not lie beyond the end point of line 1
      line2P1X - double; x-coordinate of start point of line 2
      line2P1Y - double; y-coordinate of start point of line 2
      line2P2X - double; x-coordinate of end point of line 2
      line2P2Y - double; y-coordinate of end point of line 2
      lowLimitLine2 - boolean; if true; the intersection may not lie before the start point of line 2
      highLimitLine2 - boolean; if true; the intersection may not lie beyond the end point of line 2
      Returns:
      Point2d; the intersection of the two lines, or null if the lines are (almost) parallel, or the intersection point lies outside the permitted range
      Throws:
      DrawRuntimeException - when any of the parameters is NaN

    • intersectionOfLines

      public static Point2d intersectionOfLines(double l1P1X, double l1P1Y, double l1P2X, double l1P2Y, double l2P1X, double l2P1Y, double l2P2X, double l2P2Y) throws DrawRuntimeException
      Compute the 2D intersection of two lines. Both lines are defined by two points (that should be distinct). The lines are considered to be infinitely long; so unless the lines are parallel; there is an intersection.
      Parameters:
      l1P1X - double; x-coordinate of start point of line segment 1
      l1P1Y - double; y-coordinate of start point of line segment 1
      l1P2X - double; x-coordinate of end point of line segment 1
      l1P2Y - double; y-coordinate of end point of line segment 1
      l2P1X - double; x-coordinate of start point of line segment 2
      l2P1Y - double; y-coordinate of start point of line segment 2
      l2P2X - double; x-coordinate of end point of line segment 2
      l2P2Y - double; y-coordinate of end point of line segment 2
      Returns:
      Point2d; the intersection of the two lines, or null if the lines are (almost) parallel
      Throws:
      DrawRuntimeException - when any of the parameters is NaN

    • intersectionOfLines

      public static Point2d intersectionOfLines(Point2d line1P1, Point2d line1P2, Point2d line2P1, Point2d line2P2) throws NullPointerException
      Compute the 2D intersection of two lines. Both lines are defined by two points (that should be distinct). The lines are considered to be infinitely long; so unless the lines are parallel; there is an intersection.
      Parameters:
      line1P1 - Point2d; first point of line 1
      line1P2 - Point2d; second point of line 1
      line2P1 - Point2d; first point of line 2
      line2P2 - Point2d; second point of line 2
      Returns:
      Point2d; the intersection of the two lines, or null if the lines are (almost) parallel
      Throws:
      NullPointerException - when any of the points is null

    • intersectionOfLineSegments

      public static Point2d intersectionOfLineSegments(Point2d line1P1, Point2d line1P2, Point2d line2P1, Point2d line2P2) throws NullPointerException, DrawRuntimeException
      Compute the 2D intersection of two line segments. Both line segments are defined by two points (that should be distinct).
      Parameters:
      line1P1 - Point2d; first point of line segment 1
      line1P2 - Point2d; second point of line segment 1
      line2P1 - Point2d; first point of line segment 2
      line2P2 - Point2d; second point of line segment 2
      Returns:
      Point2d; the intersection of the two line segments, or null if the lines are parallel (within rounding error), or do not intersect
      Throws:
      NullPointerException - when any of the points is null
      DrawRuntimeException - when any of the line segments is ill-defined (begin point equals end point), or the two line segments are parallel or overlapping

    • intersectionOfLineSegments

      public static Point2d intersectionOfLineSegments(double line1P1X, double line1P1Y, double line1P2X, double line1P2Y, double line2P1X, double line2P1Y, double line2P2X, double line2P2Y) throws DrawRuntimeException
      Compute the 2D intersection of two line segments. Both line segments are defined by two points (that should be distinct).
      Parameters:
      line1P1X - double; x coordinate of start point of first line segment
      line1P1Y - double; y coordinate of start point of first line segment
      line1P2X - double; x coordinate of end point of first line segment
      line1P2Y - double; y coordinate of end point of first line segment
      line2P1X - double; x coordinate of start point of second line segment
      line2P1Y - double; y coordinate of start point of second line segment
      line2P2X - double; x coordinate of end point of second line segment
      line2P2Y - double; y coordinate of end point of second line segment
      Returns:
      Point2d; the intersection of the two line segments, or null if the lines are parallel (within rounding error), or do not intersect
      Throws:
      DrawRuntimeException - when any of the values is NaN

    • intersectionOfLineSegments

      public static Point2d intersectionOfLineSegments(LineSegment2d segment1, LineSegment2d segment2)
      Compute the 2D intersection of two line segments.
      Parameters:
      segment1 - LineSegment; the first line segment
      segment2 - LineSegment; the other line segment
      Returns:
      Point2d; the intersection of the line segments, or null if the line segments do not intersect

    • closestPointOnSegment

      public Point2d closestPointOnSegment(Point2d segmentPoint1, Point2d segmentPoint2)
      Description copied from interface: Point
      Project a point on a line segment. If the the projected points lies outside the line segment, the nearest end point of the line segment is returned. Otherwise the returned point lies between the end points of the line segment.
      Adapted from example code provided by Paul Bourke.
      Specified by:
      closestPointOnSegment in interface Point<Point2d>
      Parameters:
      segmentPoint1 - P; start of line segment
      segmentPoint2 - P; end of line segment
      Returns:
      P; either segmentPoint1, or segmentPoint2 or a new Point2d that lies somewhere in between those two.

    • closestPointOnLine

      public Point2d closestPointOnLine(double p1X, double p1Y, double p2X, double p2Y, Boolean lowLimitHandling, Boolean highLimitHandling) throws DrawRuntimeException
      Compute the closest point on a line with optional limiting of the result on either end.
      Parameters:
      p1X - double; the x coordinate of the first point on the line
      p1Y - double; the y coordinate of the first point on the line
      p2X - double; the x coordinate of the second point on the line
      p2Y - double; the y coordinate of the second point on the line
      lowLimitHandling - Boolean; controls handling of results that lie before the first point of the line. If null; this method returns null; else if true; this method returns (p1X,p1Y); else (lowLimitHandling is false); this method will return the closest point on the line
      highLimitHandling - Boolean; controls the handling of results that lie beyond the second point of the line. If null; this method returns null; else if true; this method returns (p2X,p2Y); else (highLimitHandling is false); this method will return the closest point on the line
      Returns:
      Point2d; the closest point on the line after applying the indicated limit handling; so the result can be null
      Throws:
      DrawRuntimeException - when any of the arguments is NaN

    • fractionalPositionOnLine

      public double fractionalPositionOnLine(double p1X, double p1Y, double p2X, double p2Y, Boolean lowLimitHandling, Boolean highLimitHandling) throws DrawRuntimeException
      Compute the fractional position of the closest point on a line with optional limiting of the result on either end. If the line has length 0; this method returns 0.0.
      Parameters:
      p1X - double; the x coordinate of the first point on the line
      p1Y - double; the y coordinate of the first point on the line
      p2X - double; the x coordinate of the second point on the line
      p2Y - double; the y coordinate of the second point on the line
      lowLimitHandling - Boolean; controls handling of results that lie before the first point of the line. If null; this method returns NaN; else if true; this method returns 0.0; else (lowLimitHandling is false); this results < 0.0 are returned
      highLimitHandling - Boolean; controls the handling of results that lie beyond the second point of the line. If null; this method returns NaN; else if true; this method returns 1.0; else (highLimitHandling is false); results > 1.0 are returned
      Returns:
      double; the fractional position of the closest point on the line. Results within the range 0.0 .. 1.0 are always returned as is.. A result < 0.0 is subject to lowLimitHandling. A result > 1.0 is subject to highLimitHandling
      Throws:
      DrawRuntimeException - when any of the arguments is NaN

    • closestPointOnSegment

      public final Point2d closestPointOnSegment(double p1X, double p1Y, double p2X, double p2Y)
      Project a point on a line segment. If the the projected points lies outside the line segment, the nearest end point of the line segment is returned. Otherwise the returned point lies between the end points of the line segment.
      Adapted from example code provided by Paul Bourke.
      Parameters:
      p1X - double; the x coordinate of the start point of the line segment
      p1Y - double; the y coordinate of the start point of the line segment
      p2X - double; the x coordinate of the end point of the line segment
      p2Y - double; the y coordinate of the end point of the line segment
      Returns:
      P; either segmentPoint1, or segmentPoint2 or a new Point2d that lies somewhere in between those two.

    • closestPointOnLine

      public Point2d closestPointOnLine(Point2d linePoint1, Point2d linePoint2) throws NullPointerException, DrawRuntimeException
      Description copied from interface: Point
      Project a point on a line.
      Adapted from example code provided by Paul Bourke.
      Specified by:
      closestPointOnLine in interface Point<Point2d>
      Parameters:
      linePoint1 - P; point on the line
      linePoint2 - P; another point on the line
      Returns:
      Point2d; a point on the line that goes through linePoint1 and linePoint2
      Throws:
      NullPointerException - when linePoint1 is null, or linePoint2 is null
      DrawRuntimeException - when linePoint1 is at the same location as linePoint2

    • closestPointOnLine

      public final Point2d closestPointOnLine(double p1X, double p1Y, double p2X, double p2Y) throws DrawRuntimeException
      Project a point on a line.
      Adapted from example code provided by Paul Bourke.
      Parameters:
      p1X - double; the x coordinate of a point of the line segment
      p1Y - double; the y coordinate of a point of the line segment
      p2X - double; the x coordinate of another point of the line segment
      p2Y - double; the y coordinate of another point of the line segment
      Returns:
      Point2d; a point on the line that goes through the points
      Throws:
      DrawRuntimeException - when the points on the line are identical

    • circleIntersections

      public static final List<Point2d> circleIntersections(Point2d center1, double radius1, Point2d center2, double radius2) throws NullPointerException, DrawRuntimeException
      Return the zero, one or two intersections between two circles. The circles must be different. Derived from pseudo code by Paul Bourke and C implementation by Tim Voght .
      Parameters:
      center1 - Point2d; the center of circle 1
      radius1 - double; the radius of circle 1
      center2 - Point2d; the center of circle 2
      radius2 - double; the radius of circle 2
      Returns:
      List<Point2d> a list of zero, one or two points
      Throws:
      NullPointerException - when center1 or center2 is null
      DrawRuntimeException - when the two circles are identical, or radius1 < 0 or radius2 < 0

    • directionTo

      public double directionTo(Point2d otherPoint)
      Return the direction to another Point2d.
      Parameters:
      otherPoint - Point2d; the other point
      Returns:
      double; the direction to the other point in Radians (towards infinite X is 0; towards infinite Y is π / 2; etc.). If the points are identical; this method returns NaN.

    • toPoint2D

      public Point2D toPoint2D()
      Return the coordinates as a java.awt.geom.Point2D.Double object.
      Returns:
      Point2D; the coordinates as a java.awt.geom.Point2D.Double object

    • toString

      public String toString()
      Description copied from interface: Drawable
      Produce a string describing the Drawable using default conversion for the (double) coordinate values. Regrettably, it is not allowed to provide a default implementation here.
      Specified by:
      toString in interface Drawable<Point2d>
      Overrides:
      toString in class Object
      Returns:
      String; a string describing the Drawable

    • toString

      public String toString(String doubleFormat, boolean doNotIncludeClassName)
      Description copied from interface: Drawable
      Produce a String describing the Drawable.
      Specified by:
      toString in interface Drawable<Point2d>
      Parameters:
      doubleFormat - String; a format string (something like "%6.3f") which will be used to render every coordinate value)
      doNotIncludeClassName - boolean; if true; the output of toString is not prefixed by the class name. This is useful for concatenating the textual representation of lots of Drawables (e.g. an array, or a List).
      Returns:
      String; textual representation of the Drawable

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object