org.openjfx/javafx-graphics/13 : com/sun/javafx/geom/Line2D.java

Line2D
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package com.sun.javafx.geom;

import com.sun.javafx.geom.transform.BaseTransform;

This Line2D represents a line segment in (x,y) coordinate space. This class, like all of the Java 2D API, uses a default coordinate system called user space in which the y-axis
values increase downward and x-axis values increase to the right.  For
more information on the user space coordinate system, see the

Coordinate Systems section of the Java 2D Programmer's Guide.
Version:     1.37, 05/05/07/**
 * This <code>Line2D</code> represents a line segment in {@code (x,y)}
 * coordinate space.  This class, like all of the Java 2D API, uses a
 * default coordinate system called <i>user space</i> in which the y-axis
 * values increase downward and x-axis values increase to the right.  For
 * more information on the user space coordinate system, see the
 * <a href="http://java.sun.com/j2se/1.3/docs/guide/2d/spec/j2d-intro.fm2.html#61857">
 * Coordinate Systems</a> section of the Java 2D Programmer's Guide.
 *
 * @version     1.37, 05/05/07
 */
public class Line2D extends Shape {
    The X coordinate of the start point of the line segment.
/**
     * The X coordinate of the start point of the line segment.
     */
    public float x1;

    The Y coordinate of the start point of the line segment.
/**
     * The Y coordinate of the start point of the line segment.
     */
    public float y1;

    The X coordinate of the end point of the line segment.
/**
     * The X coordinate of the end point of the line segment.
     */
    public float x2;

    The Y coordinate of the end point of the line segment.
/**
     * The Y coordinate of the end point of the line segment.
     */
    public float y2;

    Constructs and initializes a Line with coordinates (0, 0) -> (0, 0).
/**
     * Constructs and initializes a Line with coordinates (0, 0) -> (0, 0).
     */
    public Line2D() { }

    Constructs and initializes a Line from the specified coordinates.
Params: x1 – the X coordinate of the start point
y1 – the Y coordinate of the start point
x2 – the X coordinate of the end point
y2 – the Y coordinate of the end point/**
     * Constructs and initializes a Line from the specified coordinates.
     * @param x1 the X coordinate of the start point
     * @param y1 the Y coordinate of the start point
     * @param x2 the X coordinate of the end point
     * @param y2 the Y coordinate of the end point
     */
    public Line2D(float x1, float y1, float x2, float y2) {
        setLine(x1, y1, x2, y2);
    }

    Constructs and initializes a Line2D from the
specified Point2D objects.
Params: p1 – the start Point2D of this line segment
p2 – the end Point2D of this line segment/**
     * Constructs and initializes a <code>Line2D</code> from the
     * specified <code>Point2D</code> objects.
     * @param p1 the start <code>Point2D</code> of this line segment
     * @param p2 the end <code>Point2D</code> of this line segment
     */
    public Line2D(Point2D p1, Point2D p2) {
        setLine(p1, p2);
    }

    Sets the location of the end points of this Line2D
to the specified float coordinates.
Params: x1 – the X coordinate of the start point
y1 – the Y coordinate of the start point
x2 – the X coordinate of the end point
y2 – the Y coordinate of the end point/**
     * Sets the location of the end points of this <code>Line2D</code>
     * to the specified float coordinates.
     * @param x1 the X coordinate of the start point
     * @param y1 the Y coordinate of the start point
     * @param x2 the X coordinate of the end point
     * @param y2 the Y coordinate of the end point
     */
    public void setLine(float x1, float y1, float x2, float y2) {
        this.x1 = x1;
        this.y1 = y1;
        this.x2 = x2;
        this.y2 = y2;
    }

    Sets the location of the end points of this Line2D to
the specified Point2D coordinates.
Params: p1 – the start Point2D of the line segment
p2 – the end Point2D of the line segment/**
     * Sets the location of the end points of this <code>Line2D</code> to
     * the specified <code>Point2D</code> coordinates.
     * @param p1 the start <code>Point2D</code> of the line segment
     * @param p2 the end <code>Point2D</code> of the line segment
     */
    public void setLine(Point2D p1, Point2D p2) {
        setLine(p1.x, p1.y, p2.x, p2.y);
    }

    Sets the location of the end points of this Line2D to
the same as those end points of the specified Line2D.
Params: l – the specified Line2D/**
     * Sets the location of the end points of this <code>Line2D</code> to
     * the same as those end points of the specified <code>Line2D</code>.
     * @param l the specified <code>Line2D</code>
     */
    public void setLine(Line2D l) {
        setLine(l.x1, l.y1, l.x2, l.y2);
    }

    {@inheritDoc}
/**
     * {@inheritDoc}
     */
    public RectBounds getBounds() {
        RectBounds b = new RectBounds();
        b.setBoundsAndSort(x1, y1, x2, y2);
        return b;
    }

    @inheritDoc /**
     * @inheritDoc
     */
    @Override
    public boolean contains(float x, float y) { return false; }

    @inheritDoc /**
     * @inheritDoc
     */
    @Override
    public boolean contains(float x, float y, float w, float h) { return false; }

    @inheritDoc /**
     * @inheritDoc
     */
    @Override
    public boolean contains(Point2D p) { return false; }

    @inheritDoc /**
     * @inheritDoc
     */
    @Override
    public boolean intersects(float x, float y, float w, float h) {
        int out1, out2;
        if ((out2 = outcode(x, y, w, h, x2, y2)) == 0) {
            return true;
        }
        float px = x1;
        float py = y1;
        while ((out1 = outcode(x, y, w, h, px, py)) != 0) {
            if ((out1 & out2) != 0) {
                return false;
            }
            if ((out1 & (OUT_LEFT | OUT_RIGHT)) != 0) {
                px = x;
                if ((out1 & OUT_RIGHT) != 0) {
                    px += w;
                }
                py = y1 + (px - x1) * (y2 - y1) / (x2 - x1);
            } else {
                py = y;
                if ((out1 & OUT_BOTTOM) != 0) {
                    py += h;
                }
                px = x1 + (py - y1) * (x2 - x1) / (y2 - y1);
            }
        }
        return true;
    }

    Returns an indicator of where the specified point (px,py) lies with respect to the line segment from (x1,y1) to (x2,y2). The return value can be either 1, -1, or 0 and indicates in which direction the specified line must pivot around its first end point, (x1,y1), in order to point at the specified point (px,py). A return value of 1 indicates that the line segment must
turn in the direction that takes the positive X axis towards
the negative Y axis.  In the default coordinate system used by
Java 2D, this direction is counterclockwise.
A return value of -1 indicates that the line segment must
turn in the direction that takes the positive X axis towards
the positive Y axis.  In the default coordinate system, this
direction is clockwise.
A return value of 0 indicates that the point lies
exactly on the line segment.  Note that an indicator value
of 0 is rare and not useful for determining colinearity
because of floating point rounding issues.
If the point is colinear with the line segment, but not between the end points, then the value will be -1 if the point lies "beyond (x1,y1)" or 1 if the point lies "beyond (x2,y2)". 
Params: x1 – the X coordinate of the start point of the
          specified line segment
y1 – the Y coordinate of the start point of the
          specified line segment
x2 – the X coordinate of the end point of the
          specified line segment
y2 – the Y coordinate of the end point of the
          specified line segment
px – the X coordinate of the specified point to be
          compared with the specified line segment
py – the Y coordinate of the specified point to be
          compared with the specified line segment
Returns: an integer that indicates the position of the third specified
         coordinates with respect to the line segment formed
         by the first two specified coordinates./**
     * Returns an indicator of where the specified point
     * {@code (px,py)} lies with respect to the line segment from
     * {@code (x1,y1)} to {@code (x2,y2)}.
     * The return value can be either 1, -1, or 0 and indicates
     * in which direction the specified line must pivot around its
     * first end point, {@code (x1,y1)}, in order to point at the
     * specified point {@code (px,py)}.
     * <p>A return value of 1 indicates that the line segment must
     * turn in the direction that takes the positive X axis towards
     * the negative Y axis.  In the default coordinate system used by
     * Java 2D, this direction is counterclockwise.
     * <p>A return value of -1 indicates that the line segment must
     * turn in the direction that takes the positive X axis towards
     * the positive Y axis.  In the default coordinate system, this
     * direction is clockwise.
     * <p>A return value of 0 indicates that the point lies
     * exactly on the line segment.  Note that an indicator value
     * of 0 is rare and not useful for determining colinearity
     * because of floating point rounding issues.
     * <p>If the point is colinear with the line segment, but
     * not between the end points, then the value will be -1 if the point
     * lies "beyond {@code (x1,y1)}" or 1 if the point lies
     * "beyond {@code (x2,y2)}".
     *
     * @param x1 the X coordinate of the start point of the
     *           specified line segment
     * @param y1 the Y coordinate of the start point of the
     *           specified line segment
     * @param x2 the X coordinate of the end point of the
     *           specified line segment
     * @param y2 the Y coordinate of the end point of the
     *           specified line segment
     * @param px the X coordinate of the specified point to be
     *           compared with the specified line segment
     * @param py the Y coordinate of the specified point to be
     *           compared with the specified line segment
     * @return an integer that indicates the position of the third specified
     *          coordinates with respect to the line segment formed
     *          by the first two specified coordinates.
     */
    public static int relativeCCW(float x1, float y1,
                  float x2, float y2,
                  float px, float py)
    {
        x2 -= x1;
        y2 -= y1;
        px -= x1;
        py -= y1;
        float ccw = px * y2 - py * x2;
        if (ccw == 0.0f) {
            // The point is colinear, classify based on which side of
            // the segment the point falls on.  We can calculate a
            // relative value using the projection of px,py onto the
            // segment - a negative value indicates the point projects
            // outside of the segment in the direction of the particular
            // endpoint used as the origin for the projection.
            ccw = px * x2 + py * y2;
            if (ccw > 0.0f) {
            // Reverse the projection to be relative to the original x2,y2
            // x2 and y2 are simply negated.
            // px and py need to have (x2 - x1) or (y2 - y1) subtracted
            //    from them (based on the original values)
            // Since we really want to get a positive answer when the
            //    point is "beyond (x2,y2)", then we want to calculate
            //    the inverse anyway - thus we leave x2 & y2 negated.
            px -= x2;
            py -= y2;
            ccw = px * x2 + py * y2;
            if (ccw < 0.0f) {
                ccw = 0.0f;
            }
            }
        }
        return (ccw < 0.0f) ? -1 : ((ccw > 0.0f) ? 1 : 0);
    }

    Returns an indicator of where the specified point (px,py) lies with respect to this line segment. See the method comments of relativeCCW(float, float, float, float, float, float) to interpret the return value. 
Params: px – the X coordinate of the specified point
          to be compared with this Line2D
py – the Y coordinate of the specified point
          to be compared with this Line2D
See Also: relativeCCW(float, float, float, float, float, float)
Returns: an integer that indicates the position of the specified
        coordinates with respect to this Line2D/**
     * Returns an indicator of where the specified point
     * {@code (px,py)} lies with respect to this line segment.
     * See the method comments of
     * {@link #relativeCCW(double, double, double, double, double, double)}
     * to interpret the return value.
     * @param px the X coordinate of the specified point
     *           to be compared with this <code>Line2D</code>
     * @param py the Y coordinate of the specified point
     *           to be compared with this <code>Line2D</code>
     * @return an integer that indicates the position of the specified
     *         coordinates with respect to this <code>Line2D</code>
     * @see #relativeCCW(double, double, double, double, double, double)
     */
    public int relativeCCW(float px, float py) {
        return relativeCCW(x1, y1, x2, y2, px, py);
    }

    Returns an indicator of where the specified Point2D lies with respect to this line segment. See the method comments of relativeCCW(float, float, float, float, float, float) to interpret the return value. 
Params: p – the specified Point2D to be compared
         with this Line2D
See Also: relativeCCW(float, float, float, float, float, float)
Returns: an integer that indicates the position of the specified
        Point2D with respect to this Line2D/**
     * Returns an indicator of where the specified <code>Point2D</code>
     * lies with respect to this line segment.
     * See the method comments of
     * {@link #relativeCCW(double, double, double, double, double, double)}
     * to interpret the return value.
     * @param p the specified <code>Point2D</code> to be compared
     *          with this <code>Line2D</code>
     * @return an integer that indicates the position of the specified
     *         <code>Point2D</code> with respect to this <code>Line2D</code>
     * @see #relativeCCW(double, double, double, double, double, double)
     */
    public int relativeCCW(Point2D p) {
        return relativeCCW(x1, y1, x2, y2, p.x, p.y);
    }

    Tests if the line segment from (x1,y1) to (x2,y2) intersects the line segment from (x3,y3) to (x4,y4). 
Params: x1 – the X coordinate of the start point of the first
          specified line segment
y1 – the Y coordinate of the start point of the first
          specified line segment
x2 – the X coordinate of the end point of the first
          specified line segment
y2 – the Y coordinate of the end point of the first
          specified line segment
x3 – the X coordinate of the start point of the second
          specified line segment
y3 – the Y coordinate of the start point of the second
          specified line segment
x4 – the X coordinate of the end point of the second
          specified line segment
y4 – the Y coordinate of the end point of the second
          specified line segment
Returns: true if the first specified line segment
         and the second specified line segment intersect
         each other; false otherwise./**
     * Tests if the line segment from {@code (x1,y1)} to
     * {@code (x2,y2)} intersects the line segment from {@code (x3,y3)}
     * to {@code (x4,y4)}.
     *
     * @param x1 the X coordinate of the start point of the first
     *           specified line segment
     * @param y1 the Y coordinate of the start point of the first
     *           specified line segment
     * @param x2 the X coordinate of the end point of the first
     *           specified line segment
     * @param y2 the Y coordinate of the end point of the first
     *           specified line segment
     * @param x3 the X coordinate of the start point of the second
     *           specified line segment
     * @param y3 the Y coordinate of the start point of the second
     *           specified line segment
     * @param x4 the X coordinate of the end point of the second
     *           specified line segment
     * @param y4 the Y coordinate of the end point of the second
     *           specified line segment
     * @return <code>true</code> if the first specified line segment
     *          and the second specified line segment intersect
     *          each other; <code>false</code> otherwise.
     */
    public static boolean linesIntersect(float x1, float y1,
                     float x2, float y2,
                     float x3, float y3,
                     float x4, float y4)
    {
    return ((relativeCCW(x1, y1, x2, y2, x3, y3) *
         relativeCCW(x1, y1, x2, y2, x4, y4) <= 0)
        && (relativeCCW(x3, y3, x4, y4, x1, y1) *
            relativeCCW(x3, y3, x4, y4, x2, y2) <= 0));
    }

    Tests if the line segment from (x1,y1) to (x2,y2) intersects this line segment. 
Params: x1 – the X coordinate of the start point of the
          specified line segment
y1 – the Y coordinate of the start point of the
          specified line segment
x2 – the X coordinate of the end point of the
          specified line segment
y2 – the Y coordinate of the end point of the
          specified line segment
Returns:  if this line segment and the specified line segment
         intersect each other; false otherwise./**
     * Tests if the line segment from {@code (x1,y1)} to
     * {@code (x2,y2)} intersects this line segment.
     *
     * @param x1 the X coordinate of the start point of the
     *           specified line segment
     * @param y1 the Y coordinate of the start point of the
     *           specified line segment
     * @param x2 the X coordinate of the end point of the
     *           specified line segment
     * @param y2 the Y coordinate of the end point of the
     *           specified line segment
     * @return <true> if this line segment and the specified line segment
     *          intersect each other; <code>false</code> otherwise.
     */
    public boolean intersectsLine(float x1, float y1, float x2, float y2) {
        return linesIntersect(x1, y1, x2, y2, this.x1, this.y1, this.x2, this.y2);
    }

    Tests if the specified line segment intersects this line segment.
Params: l – the specified Line2D
Returns: true if this line segment and the specified line
         segment intersect each other;
         false otherwise./**
     * Tests if the specified line segment intersects this line segment.
     * @param l the specified <code>Line2D</code>
     * @return <code>true</code> if this line segment and the specified line
     *          segment intersect each other;
     *          <code>false</code> otherwise.
     */
    public boolean intersectsLine(Line2D l) {
        return linesIntersect(l.x1, l.y1, l.x2, l.y2, this.x1, this.y1, this.x2, this.y2);
    }

    Returns the square of the distance from a point to a line segment.
The distance measured is the distance between the specified
point and the closest point between the specified end points.
If the specified point intersects the line segment in between the
end points, this method returns 0.0.
Params: x1 – the X coordinate of the start point of the
          specified line segment
y1 – the Y coordinate of the start point of the
          specified line segment
x2 – the X coordinate of the end point of the
          specified line segment
y2 – the Y coordinate of the end point of the
          specified line segment
px – the X coordinate of the specified point being
          measured against the specified line segment
py – the Y coordinate of the specified point being
          measured against the specified line segment
See Also: ptLineDistSq(float, float, float, float, float, float)
Returns: a double value that is the square of the distance from the
         specified point to the specified line segment./**
     * Returns the square of the distance from a point to a line segment.
     * The distance measured is the distance between the specified
     * point and the closest point between the specified end points.
     * If the specified point intersects the line segment in between the
     * end points, this method returns 0.0.
     *
     * @param x1 the X coordinate of the start point of the
     *           specified line segment
     * @param y1 the Y coordinate of the start point of the
     *           specified line segment
     * @param x2 the X coordinate of the end point of the
     *           specified line segment
     * @param y2 the Y coordinate of the end point of the
     *           specified line segment
     * @param px the X coordinate of the specified point being
     *           measured against the specified line segment
     * @param py the Y coordinate of the specified point being
     *           measured against the specified line segment
     * @return a double value that is the square of the distance from the
     *          specified point to the specified line segment.
     * @see #ptLineDistSq(double, double, double, double, double, double)
     */
    public static float ptSegDistSq(float x1, float y1,
                     float x2, float y2,
                     float px, float py)
    {
        // Adjust vectors relative to x1,y1
        // x2,y2 becomes relative vector from x1,y1 to end of segment
        x2 -= x1;
        y2 -= y1;
        // px,py becomes relative vector from x1,y1 to test point
        px -= x1;
        py -= y1;
        float dotprod = px * x2 + py * y2;
        float projlenSq;
        if (dotprod <= 0f) {
            // px,py is on the side of x1,y1 away from x2,y2
            // distance to segment is length of px,py vector
            // "length of its (clipped) projection" is now 0.0
            projlenSq = 0f;
        } else {
            // switch to backwards vectors relative to x2,y2
            // x2,y2 are already the negative of x1,y1=>x2,y2
            // to get px,py to be the negative of px,py=>x2,y2
            // the dot product of two negated vectors is the same
            // as the dot product of the two normal vectors
            px = x2 - px;
            py = y2 - py;
            dotprod = px * x2 + py * y2;
            if (dotprod <= 0f) {
                // px,py is on the side of x2,y2 away from x1,y1
                // distance to segment is length of (backwards) px,py vector
                // "length of its (clipped) projection" is now 0.0
                projlenSq = 0f;
            } else {
                // px,py is between x1,y1 and x2,y2
                // dotprod is the length of the px,py vector
                // projected on the x2,y2=>x1,y1 vector times the
                // length of the x2,y2=>x1,y1 vector
                projlenSq = dotprod * dotprod / (x2 * x2 + y2 * y2);
            }
        }
        // Distance to line is now the length of the relative point
        // vector minus the length of its projection onto the line
        // (which is zero if the projection falls outside the range
        //  of the line segment).
        float lenSq = px * px + py * py - projlenSq;
        if (lenSq < 0f) {
            lenSq = 0f;
        }
        return lenSq;
    }

    Returns the distance from a point to a line segment.
The distance measured is the distance between the specified
point and the closest point between the specified end points.
If the specified point intersects the line segment in between the
end points, this method returns 0.0.
Params: x1 – the X coordinate of the start point of the
          specified line segment
y1 – the Y coordinate of the start point of the
          specified line segment
x2 – the X coordinate of the end point of the
          specified line segment
y2 – the Y coordinate of the end point of the
          specified line segment
px – the X coordinate of the specified point being
          measured against the specified line segment
py – the Y coordinate of the specified point being
          measured against the specified line segment
See Also: ptLineDist(float, float, float, float, float, float)
Returns: a double value that is the distance from the specified point
             to the specified line segment./**
     * Returns the distance from a point to a line segment.
     * The distance measured is the distance between the specified
     * point and the closest point between the specified end points.
     * If the specified point intersects the line segment in between the
     * end points, this method returns 0.0.
     *
     * @param x1 the X coordinate of the start point of the
     *           specified line segment
     * @param y1 the Y coordinate of the start point of the
     *           specified line segment
     * @param x2 the X coordinate of the end point of the
     *           specified line segment
     * @param y2 the Y coordinate of the end point of the
     *           specified line segment
     * @param px the X coordinate of the specified point being
     *           measured against the specified line segment
     * @param py the Y coordinate of the specified point being
     *           measured against the specified line segment
     * @return a double value that is the distance from the specified point
     *              to the specified line segment.
     * @see #ptLineDist(double, double, double, double, double, double)
     */
    public static float ptSegDist(float x1, float y1,
                   float x2, float y2,
                   float px, float py)
    {
        return (float) Math.sqrt(ptSegDistSq(x1, y1, x2, y2, px, py));
    }

    Returns the square of the distance from a point to this line segment.
The distance measured is the distance between the specified
point and the closest point between the current line's end points.
If the specified point intersects the line segment in between the
end points, this method returns 0.0.
Params: px – the X coordinate of the specified point being
          measured against this line segment
py – the Y coordinate of the specified point being
          measured against this line segment
See Also: ptLineDistSq(float, float)
Returns: a double value that is the square of the distance from the
         specified point to the current line segment./**
     * Returns the square of the distance from a point to this line segment.
     * The distance measured is the distance between the specified
     * point and the closest point between the current line's end points.
     * If the specified point intersects the line segment in between the
     * end points, this method returns 0.0.
     *
     * @param px the X coordinate of the specified point being
     *           measured against this line segment
     * @param py the Y coordinate of the specified point being
     *           measured against this line segment
     * @return a double value that is the square of the distance from the
     *          specified point to the current line segment.
     * @see #ptLineDistSq(double, double)
     */
    public float ptSegDistSq(float px, float py) {
        return ptSegDistSq(x1, y1, x2, y2, px, py);
    }

    Returns the square of the distance from a Point2D to
this line segment.
The distance measured is the distance between the specified
point and the closest point between the current line's end points.
If the specified point intersects the line segment in between the
end points, this method returns 0.0.
Params: pt – the specified Point2D being measured against
          this line segment.
See Also: ptLineDistSq(Point2D)
Returns: a double value that is the square of the distance from the
         specified Point2D to the current
         line segment./**
     * Returns the square of the distance from a <code>Point2D</code> to
     * this line segment.
     * The distance measured is the distance between the specified
     * point and the closest point between the current line's end points.
     * If the specified point intersects the line segment in between the
     * end points, this method returns 0.0.
     * @param pt the specified <code>Point2D</code> being measured against
     *           this line segment.
     * @return a double value that is the square of the distance from the
     *          specified <code>Point2D</code> to the current
     *          line segment.
     * @see #ptLineDistSq(Point2D)
     */
    public float ptSegDistSq(Point2D pt) {
        return ptSegDistSq(x1, y1, x2, y2, pt.x, pt.y);
    }

    Returns the distance from a point to this line segment.
The distance measured is the distance between the specified
point and the closest point between the current line's end points.
If the specified point intersects the line segment in between the
end points, this method returns 0.0.
Params: px – the X coordinate of the specified point being
          measured against this line segment
py – the Y coordinate of the specified point being
          measured against this line segment
See Also: ptLineDist(float, float)
Returns: a double value that is the distance from the specified
         point to the current line segment./**
     * Returns the distance from a point to this line segment.
     * The distance measured is the distance between the specified
     * point and the closest point between the current line's end points.
     * If the specified point intersects the line segment in between the
     * end points, this method returns 0.0.
     *
     * @param px the X coordinate of the specified point being
     *           measured against this line segment
     * @param py the Y coordinate of the specified point being
     *           measured against this line segment
     * @return a double value that is the distance from the specified
     *          point to the current line segment.
     * @see #ptLineDist(double, double)
     */
    public double ptSegDist(float px, float py) {
        return ptSegDist(x1, y1, x2, y2, px, py);
    }

    Returns the distance from a Point2D to this line
segment.
The distance measured is the distance between the specified
point and the closest point between the current line's end points.
If the specified point intersects the line segment in between the
end points, this method returns 0.0.
Params: pt – the specified Point2D being measured
     against this line segment
See Also: ptLineDist(Point2D)
Returns: a double value that is the distance from the specified
             Point2D to the current line
             segment./**
     * Returns the distance from a <code>Point2D</code> to this line
     * segment.
     * The distance measured is the distance between the specified
     * point and the closest point between the current line's end points.
     * If the specified point intersects the line segment in between the
     * end points, this method returns 0.0.
     * @param pt the specified <code>Point2D</code> being measured
     *      against this line segment
     * @return a double value that is the distance from the specified
     *              <code>Point2D</code> to the current line
     *              segment.
     * @see #ptLineDist(Point2D)
     */
    public float ptSegDist(Point2D pt) {
        return ptSegDist(x1, y1, x2, y2, pt.x, pt.y);
    }

    Returns the square of the distance from a point to a line.
The distance measured is the distance between the specified
point and the closest point on the infinitely-extended line
defined by the specified coordinates.  If the specified point
intersects the line, this method returns 0.0.
Params: x1 – the X coordinate of the start point of the specified line
y1 – the Y coordinate of the start point of the specified line
x2 – the X coordinate of the end point of the specified line
y2 – the Y coordinate of the end point of the specified line
px – the X coordinate of the specified point being
          measured against the specified line
py – the Y coordinate of the specified point being
          measured against the specified line
See Also: ptSegDistSq(float, float, float, float, float, float)
Returns: a double value that is the square of the distance from the
         specified point to the specified line./**
     * Returns the square of the distance from a point to a line.
     * The distance measured is the distance between the specified
     * point and the closest point on the infinitely-extended line
     * defined by the specified coordinates.  If the specified point
     * intersects the line, this method returns 0.0.
     *
     * @param x1 the X coordinate of the start point of the specified line
     * @param y1 the Y coordinate of the start point of the specified line
     * @param x2 the X coordinate of the end point of the specified line
     * @param y2 the Y coordinate of the end point of the specified line
     * @param px the X coordinate of the specified point being
     *           measured against the specified line
     * @param py the Y coordinate of the specified point being
     *           measured against the specified line
     * @return a double value that is the square of the distance from the
     *          specified point to the specified line.
     * @see #ptSegDistSq(double, double, double, double, double, double)
     */
    public static float ptLineDistSq(float x1, float y1,
                      float x2, float y2,
                      float px, float py)
    {
        // Adjust vectors relative to x1,y1
        // x2,y2 becomes relative vector from x1,y1 to end of segment
        x2 -= x1;
        y2 -= y1;
        // px,py becomes relative vector from x1,y1 to test point
        px -= x1;
        py -= y1;
        float dotprod = px * x2 + py * y2;
        // dotprod is the length of the px,py vector
        // projected on the x1,y1=>x2,y2 vector times the
        // length of the x1,y1=>x2,y2 vector
        float projlenSq = dotprod * dotprod / (x2 * x2 + y2 * y2);
        // Distance to line is now the length of the relative point
        // vector minus the length of its projection onto the line
        float lenSq = px * px + py * py - projlenSq;
        if (lenSq < 0f) {
            lenSq = 0f;
        }
        return lenSq;
    }

    Returns the distance from a point to a line.
The distance measured is the distance between the specified
point and the closest point on the infinitely-extended line
defined by the specified coordinates.  If the specified point
intersects the line, this method returns 0.0.
Params: x1 – the X coordinate of the start point of the specified line
y1 – the Y coordinate of the start point of the specified line
x2 – the X coordinate of the end point of the specified line
y2 – the Y coordinate of the end point of the specified line
px – the X coordinate of the specified point being
          measured against the specified line
py – the Y coordinate of the specified point being
          measured against the specified line
See Also: ptSegDist(float, float, float, float, float, float)
Returns: a double value that is the distance from the specified
          point to the specified line./**
     * Returns the distance from a point to a line.
     * The distance measured is the distance between the specified
     * point and the closest point on the infinitely-extended line
     * defined by the specified coordinates.  If the specified point
     * intersects the line, this method returns 0.0.
     *
     * @param x1 the X coordinate of the start point of the specified line
     * @param y1 the Y coordinate of the start point of the specified line
     * @param x2 the X coordinate of the end point of the specified line
     * @param y2 the Y coordinate of the end point of the specified line
     * @param px the X coordinate of the specified point being
     *           measured against the specified line
     * @param py the Y coordinate of the specified point being
     *           measured against the specified line
     * @return a double value that is the distance from the specified
     *           point to the specified line.
     * @see #ptSegDist(double, double, double, double, double, double)
     */
    public static float ptLineDist(float x1, float y1,
                    float x2, float y2,
                    float px, float py)
    {
        return (float) Math.sqrt(ptLineDistSq(x1, y1, x2, y2, px, py));
    }

    Returns the square of the distance from a point to this line.
The distance measured is the distance between the specified
point and the closest point on the infinitely-extended line
defined by this Line2D.  If the specified point
intersects the line, this method returns 0.0.
Params: px – the X coordinate of the specified point being
          measured against this line
py – the Y coordinate of the specified point being
          measured against this line
See Also: ptSegDistSq(float, float)
Returns: a double value that is the square of the distance from a
         specified point to the current line./**
     * Returns the square of the distance from a point to this line.
     * The distance measured is the distance between the specified
     * point and the closest point on the infinitely-extended line
     * defined by this <code>Line2D</code>.  If the specified point
     * intersects the line, this method returns 0.0.
     *
     * @param px the X coordinate of the specified point being
     *           measured against this line
     * @param py the Y coordinate of the specified point being
     *           measured against this line
     * @return a double value that is the square of the distance from a
     *          specified point to the current line.
     * @see #ptSegDistSq(double, double)
     */
    public float ptLineDistSq(float px, float py) {
        return ptLineDistSq(x1, y1, x2, y2, px, py);
    }

    Returns the square of the distance from a specified
Point2D to this line.
The distance measured is the distance between the specified
point and the closest point on the infinitely-extended line
defined by this Line2D.  If the specified point
intersects the line, this method returns 0.0.
Params: pt – the specified Point2D being measured
          against this line
See Also: ptSegDistSq(Point2D)
Returns: a double value that is the square of the distance from a
         specified Point2D to the current
         line./**
     * Returns the square of the distance from a specified
     * <code>Point2D</code> to this line.
     * The distance measured is the distance between the specified
     * point and the closest point on the infinitely-extended line
     * defined by this <code>Line2D</code>.  If the specified point
     * intersects the line, this method returns 0.0.
     * @param pt the specified <code>Point2D</code> being measured
     *           against this line
     * @return a double value that is the square of the distance from a
     *          specified <code>Point2D</code> to the current
     *          line.
     * @see #ptSegDistSq(Point2D)
     */
    public float ptLineDistSq(Point2D pt) {
        return ptLineDistSq(x1, y1, x2, y2, pt.x, pt.y);
    }

    Returns the distance from a point to this line.
The distance measured is the distance between the specified
point and the closest point on the infinitely-extended line
defined by this Line2D.  If the specified point
intersects the line, this method returns 0.0.
Params: px – the X coordinate of the specified point being
          measured against this line
py – the Y coordinate of the specified point being
          measured against this line
See Also: ptSegDist(float, float)
Returns: a double value that is the distance from a specified point
         to the current line./**
     * Returns the distance from a point to this line.
     * The distance measured is the distance between the specified
     * point and the closest point on the infinitely-extended line
     * defined by this <code>Line2D</code>.  If the specified point
     * intersects the line, this method returns 0.0.
     *
     * @param px the X coordinate of the specified point being
     *           measured against this line
     * @param py the Y coordinate of the specified point being
     *           measured against this line
     * @return a double value that is the distance from a specified point
     *          to the current line.
     * @see #ptSegDist(double, double)
     */
    public float ptLineDist(float px, float py) {
        return ptLineDist(x1, y1, x2, y2, px, py);
    }

    Returns the distance from a Point2D to this line.
The distance measured is the distance between the specified
point and the closest point on the infinitely-extended line
defined by this Line2D.  If the specified point
intersects the line, this method returns 0.0.
Params: pt – the specified Point2D being measured
See Also: ptSegDist(Point2D)
Returns: a double value that is the distance from a specified
         Point2D to the current line./**
     * Returns the distance from a <code>Point2D</code> to this line.
     * The distance measured is the distance between the specified
     * point and the closest point on the infinitely-extended line
     * defined by this <code>Line2D</code>.  If the specified point
     * intersects the line, this method returns 0.0.
     * @param pt the specified <code>Point2D</code> being measured
     * @return a double value that is the distance from a specified
     *          <code>Point2D</code> to the current line.
     * @see #ptSegDist(Point2D)
     */
    public float ptLineDist(Point2D pt) {
        return ptLineDist(x1, y1, x2, y2, pt.x, pt.y);
    }

    Returns an iteration object that defines the boundary of this
Line2D.
The iterator for this class is not multi-threaded safe,
which means that this Line2D class does not
guarantee that modifications to the geometry of this
Line2D object do not affect any iterations of that
geometry that are already in process.
Params: tx – the specified BaseTransform
Returns: a PathIterator that defines the boundary of this Line2D./**
     * Returns an iteration object that defines the boundary of this
     * <code>Line2D</code>.
     * The iterator for this class is not multi-threaded safe,
     * which means that this <code>Line2D</code> class does not
     * guarantee that modifications to the geometry of this
     * <code>Line2D</code> object do not affect any iterations of that
     * geometry that are already in process.
     * @param tx the specified {@link BaseTransform}
     * @return a {@link PathIterator} that defines the boundary of this
     *      <code>Line2D</code>.
     */
    public PathIterator getPathIterator(BaseTransform tx) {
        return new LineIterator(this, tx);
    }

    Returns an iteration object that defines the boundary of this
flattened Line2D.
The iterator for this class is not multi-threaded safe,
which means that this Line2D class does not
guarantee that modifications to the geometry of this
Line2D object do not affect any iterations of that
geometry that are already in process.
Params: tx – the specified BaseTransform
flatness – the maximum amount that the control points for a
     given curve can vary from colinear before a subdivided
     curve is replaced by a straight line connecting the
     end points.  Since a Line2D object is
         always flat, this parameter is ignored.
Returns: a PathIterator that defines the boundary of the
         flattened Line2D/**
     * Returns an iteration object that defines the boundary of this
     * flattened <code>Line2D</code>.
     * The iterator for this class is not multi-threaded safe,
     * which means that this <code>Line2D</code> class does not
     * guarantee that modifications to the geometry of this
     * <code>Line2D</code> object do not affect any iterations of that
     * geometry that are already in process.
     * @param tx the specified <code>BaseTransform</code>
     * @param flatness the maximum amount that the control points for a
     *      given curve can vary from colinear before a subdivided
     *      curve is replaced by a straight line connecting the
     *      end points.  Since a <code>Line2D</code> object is
     *          always flat, this parameter is ignored.
     * @return a <code>PathIterator</code> that defines the boundary of the
     *          flattened <code>Line2D</code>
     */
    public PathIterator getPathIterator(BaseTransform tx, float flatness) {
        return new LineIterator(this, tx);
    }

    @Override
    public Line2D copy() {
        return new Line2D(x1, y1, x2, y2);
    }

    @Override
    public int hashCode() {
        int bits = java.lang.Float.floatToIntBits(x1);
        bits += java.lang.Float.floatToIntBits(y1) * 37;
        bits += java.lang.Float.floatToIntBits(x2) * 43;
        bits += java.lang.Float.floatToIntBits(y2) * 47;
        return bits;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (obj instanceof Line2D) {
            Line2D line = (Line2D) obj;
            return ((x1 == line.x1) && (y1 == line.y1) &&
                    (x2 == line.x2) && (y2 == line.y2));
        }
        return false;
    }
}
Params:	px – the X coordinate of the specified point to be compared with this `Line2D` py – the Y coordinate of the specified point to be compared with this `Line2D`
See Also:	relativeCCW(float, float, float, float, float, float)
Returns:	an integer that indicates the position of the specified coordinates with respect to this `Line2D`
Params:	p – the specified `Point2D` to be compared with this `Line2D`
See Also:	relativeCCW(float, float, float, float, float, float)
Returns:	an integer that indicates the position of the specified `Point2D` with respect to this `Line2D`
Params:	x1 – the X coordinate of the start point of the specified line segment y1 – the Y coordinate of the start point of the specified line segment x2 – the X coordinate of the end point of the specified line segment y2 – the Y coordinate of the end point of the specified line segment
Returns:	if this line segment and the specified line segment intersect each other; `false` otherwise.
Params:	l – the specified `Line2D`
Returns:	`true` if this line segment and the specified line segment intersect each other; `false` otherwise.
Params:	pt – the specified `Point2D` being measured against this line segment.
See Also:	ptLineDistSq(Point2D)
Returns:	a double value that is the square of the distance from the specified `Point2D` to the current line segment.
Params:	tx – the specified `BaseTransform`
Returns:	a `PathIterator` that defines the boundary of this `Line2D`.
Params:	tx – the specified `BaseTransform` flatness – the maximum amount that the control points for a given curve can vary from colinear before a subdivided curve is replaced by a straight line connecting the end points. Since a `Line2D` object is always flat, this parameter is ignored.
Returns:	a `PathIterator` that defines the boundary of the flattened `Line2D`
/

org.openjfx/ javafx-graphics/ 13/ com/sun/javafx/geom/Line2D.java
