https://openjdk.java.net/ 
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package java.awt.geom;

import java.awt.Shape;
import java.awt.Rectangle;
import java.io.Serializable;
import sun.awt.geom.Curve;


The QuadCurve2D class defines a quadratic parametric curve segment in (x,y) coordinate space. 

This class is only the abstract superclass for all objects that
store a 2D quadratic curve segment.
The actual storage representation of the coordinates is left to
the subclass.

Author:     Jim Graham
Since:1.2
/**
 * The {@code QuadCurve2D} class defines a quadratic parametric curve
 * segment in {@code (x,y)} coordinate space.
 * <p>
 * This class is only the abstract superclass for all objects that
 * store a 2D quadratic curve segment.
 * The actual storage representation of the coordinates is left to
 * the subclass.
 *
 * @author      Jim Graham
 * @since 1.2
 */
public abstract class QuadCurve2D implements Shape, Cloneable {

    
A quadratic parametric curve segment specified with float coordinates. 
Since:1.2
/**
     * A quadratic parametric curve segment specified with
     * {@code float} coordinates.
     *
     * @since 1.2
     */
    public static class Float extends QuadCurve2D implements Serializable {
        
The X coordinate of the start point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The X coordinate of the start point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public float x1;

        
The Y coordinate of the start point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The Y coordinate of the start point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public float y1;

        
The X coordinate of the control point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The X coordinate of the control point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public float ctrlx;

        
The Y coordinate of the control point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The Y coordinate of the control point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public float ctrly;

        
The X coordinate of the end point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The X coordinate of the end point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public float x2;

        
The Y coordinate of the end point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The Y coordinate of the end point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public float y2;

        
Constructs and initializes a QuadCurve2D with coordinates (0, 0, 0, 0, 0, 0). 
Since:1.2
/**
         * Constructs and initializes a {@code QuadCurve2D} with
         * coordinates (0, 0, 0, 0, 0, 0).
         * @since 1.2
         */
        public Float() {
        }

        
Constructs and initializes a QuadCurve2D from the specified float coordinates. 
Params:
  • x1 – the X coordinate of the start point
  • y1 – the Y coordinate of the start point
  • ctrlx – the X coordinate of the control point
  • ctrly – the Y coordinate of the control point
  • x2 – the X coordinate of the end point
  • y2 – the Y coordinate of the end point
Since:1.2
/**
         * Constructs and initializes a {@code QuadCurve2D} from the
         * specified {@code float} coordinates.
         *
         * @param x1 the X coordinate of the start point
         * @param y1 the Y coordinate of the start point
         * @param ctrlx the X coordinate of the control point
         * @param ctrly the Y coordinate of the control point
         * @param x2 the X coordinate of the end point
         * @param y2 the Y coordinate of the end point
         * @since 1.2
         */
        public Float(float x1, float y1,
                     float ctrlx, float ctrly,
                     float x2, float y2)
        {
            setCurve(x1, y1, ctrlx, ctrly, x2, y2);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getX1() {
            return (double) x1;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getY1() {
            return (double) y1;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Point2D getP1() {
            return new Point2D.Float(x1, y1);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getCtrlX() {
            return (double) ctrlx;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getCtrlY() {
            return (double) ctrly;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Point2D getCtrlPt() {
            return new Point2D.Float(ctrlx, ctrly);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getX2() {
            return (double) x2;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getY2() {
            return (double) y2;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Point2D getP2() {
            return new Point2D.Float(x2, y2);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public void setCurve(double x1, double y1,
                             double ctrlx, double ctrly,
                             double x2, double y2)
        {
            this.x1    = (float) x1;
            this.y1    = (float) y1;
            this.ctrlx = (float) ctrlx;
            this.ctrly = (float) ctrly;
            this.x2    = (float) x2;
            this.y2    = (float) y2;
        }

        
Sets the location of the end points and control point of this curve to the specified float coordinates. 
Params:
  • x1 – the X coordinate of the start point
  • y1 – the Y coordinate of the start point
  • ctrlx – the X coordinate of the control point
  • ctrly – the Y coordinate of the control point
  • x2 – the X coordinate of the end point
  • y2 – the Y coordinate of the end point
Since:1.2
/**
         * Sets the location of the end points and control point of this curve
         * to the specified {@code float} coordinates.
         *
         * @param x1 the X coordinate of the start point
         * @param y1 the Y coordinate of the start point
         * @param ctrlx the X coordinate of the control point
         * @param ctrly the Y coordinate of the control point
         * @param x2 the X coordinate of the end point
         * @param y2 the Y coordinate of the end point
         * @since 1.2
         */
        public void setCurve(float x1, float y1,
                             float ctrlx, float ctrly,
                             float x2, float y2)
        {
            this.x1    = x1;
            this.y1    = y1;
            this.ctrlx = ctrlx;
            this.ctrly = ctrly;
            this.x2    = x2;
            this.y2    = y2;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Rectangle2D getBounds2D() {
            float left   = Math.min(Math.min(x1, x2), ctrlx);
            float top    = Math.min(Math.min(y1, y2), ctrly);
            float right  = Math.max(Math.max(x1, x2), ctrlx);
            float bottom = Math.max(Math.max(y1, y2), ctrly);
            return new Rectangle2D.Float(left, top,
                                         right - left, bottom - top);
        }

        /*
         * JDK 1.6 serialVersionUID
         */
        private static final long serialVersionUID = -8511188402130719609L;
    }

    
A quadratic parametric curve segment specified with double coordinates. 
Since:1.2
/**
     * A quadratic parametric curve segment specified with
     * {@code double} coordinates.
     *
     * @since 1.2
     */
    public static class Double extends QuadCurve2D implements Serializable {
        
The X coordinate of the start point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The X coordinate of the start point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public double x1;

        
The Y coordinate of the start point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The Y coordinate of the start point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public double y1;

        
The X coordinate of the control point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The X coordinate of the control point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public double ctrlx;

        
The Y coordinate of the control point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The Y coordinate of the control point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public double ctrly;

        
The X coordinate of the end point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The X coordinate of the end point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public double x2;

        
The Y coordinate of the end point of the quadratic curve
segment.

Since:1.2
@serial
/**
         * The Y coordinate of the end point of the quadratic curve
         * segment.
         * @since 1.2
         * @serial
         */
        public double y2;

        
Constructs and initializes a QuadCurve2D with coordinates (0, 0, 0, 0, 0, 0). 
Since:1.2
/**
         * Constructs and initializes a {@code QuadCurve2D} with
         * coordinates (0, 0, 0, 0, 0, 0).
         * @since 1.2
         */
        public Double() {
        }

        
Constructs and initializes a QuadCurve2D from the specified double coordinates. 
Params:
  • x1 – the X coordinate of the start point
  • y1 – the Y coordinate of the start point
  • ctrlx – the X coordinate of the control point
  • ctrly – the Y coordinate of the control point
  • x2 – the X coordinate of the end point
  • y2 – the Y coordinate of the end point
Since:1.2
/**
         * Constructs and initializes a {@code QuadCurve2D} from the
         * specified {@code double} coordinates.
         *
         * @param x1 the X coordinate of the start point
         * @param y1 the Y coordinate of the start point
         * @param ctrlx the X coordinate of the control point
         * @param ctrly the Y coordinate of the control point
         * @param x2 the X coordinate of the end point
         * @param y2 the Y coordinate of the end point
         * @since 1.2
         */
        public Double(double x1, double y1,
                      double ctrlx, double ctrly,
                      double x2, double y2)
        {
            setCurve(x1, y1, ctrlx, ctrly, x2, y2);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getX1() {
            return x1;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getY1() {
            return y1;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Point2D getP1() {
            return new Point2D.Double(x1, y1);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getCtrlX() {
            return ctrlx;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getCtrlY() {
            return ctrly;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Point2D getCtrlPt() {
            return new Point2D.Double(ctrlx, ctrly);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getX2() {
            return x2;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getY2() {
            return y2;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Point2D getP2() {
            return new Point2D.Double(x2, y2);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public void setCurve(double x1, double y1,
                             double ctrlx, double ctrly,
                             double x2, double y2)
        {
            this.x1    = x1;
            this.y1    = y1;
            this.ctrlx = ctrlx;
            this.ctrly = ctrly;
            this.x2    = x2;
            this.y2    = y2;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Rectangle2D getBounds2D() {
            double left   = Math.min(Math.min(x1, x2), ctrlx);
            double top    = Math.min(Math.min(y1, y2), ctrly);
            double right  = Math.max(Math.max(x1, x2), ctrlx);
            double bottom = Math.max(Math.max(y1, y2), ctrly);
            return new Rectangle2D.Double(left, top,
                                          right - left, bottom - top);
        }

        /*
         * JDK 1.6 serialVersionUID
         */
        private static final long serialVersionUID = 4217149928428559721L;
    }

    
This is an abstract class that cannot be instantiated directly.
Type-specific implementation subclasses are available for
instantiation and provide a number of formats for storing
the information necessary to satisfy the various accessor
methods below.

See Also:
Since:1.2
/**
     * This is an abstract class that cannot be instantiated directly.
     * Type-specific implementation subclasses are available for
     * instantiation and provide a number of formats for storing
     * the information necessary to satisfy the various accessor
     * methods below.
     *
     * @see java.awt.geom.QuadCurve2D.Float
     * @see java.awt.geom.QuadCurve2D.Double
     * @since 1.2
     */
    protected QuadCurve2D() {
    }

    
Returns the X coordinate of the start point in double in precision. 
Returns:the X coordinate of the start point.
Since:1.2
/**
     * Returns the X coordinate of the start point in
     * {@code double} in precision.
     * @return the X coordinate of the start point.
     * @since 1.2
     */
    public abstract double getX1();

    
Returns the Y coordinate of the start point in double precision. 
Returns:the Y coordinate of the start point.
Since:1.2
/**
     * Returns the Y coordinate of the start point in
     * {@code double} precision.
     * @return the Y coordinate of the start point.
     * @since 1.2
     */
    public abstract double getY1();

    
Returns the start point.

Returns:a Point2D that is the start point of this QuadCurve2D.
Since:1.2
/**
     * Returns the start point.
     * @return a {@code Point2D} that is the start point of this
     *          {@code QuadCurve2D}.
     * @since 1.2
     */
    public abstract Point2D getP1();

    
Returns the X coordinate of the control point in double precision. 
Returns:X coordinate the control point
Since:1.2
/**
     * Returns the X coordinate of the control point in
     * {@code double} precision.
     * @return X coordinate the control point
     * @since 1.2
     */
    public abstract double getCtrlX();

    
Returns the Y coordinate of the control point in double precision. 
Returns:the Y coordinate of the control point.
Since:1.2
/**
     * Returns the Y coordinate of the control point in
     * {@code double} precision.
     * @return the Y coordinate of the control point.
     * @since 1.2
     */
    public abstract double getCtrlY();

    
Returns the control point.

Returns:a Point2D that is the control point of this Point2D.
Since:1.2
/**
     * Returns the control point.
     * @return a {@code Point2D} that is the control point of this
     *          {@code Point2D}.
     * @since 1.2
     */
    public abstract Point2D getCtrlPt();

    
Returns the X coordinate of the end point in double precision. 
Returns:the x coordinate of the end point.
Since:1.2
/**
     * Returns the X coordinate of the end point in
     * {@code double} precision.
     * @return the x coordinate of the end point.
     * @since 1.2
     */
    public abstract double getX2();

    
Returns the Y coordinate of the end point in double precision. 
Returns:the Y coordinate of the end point.
Since:1.2
/**
     * Returns the Y coordinate of the end point in
     * {@code double} precision.
     * @return the Y coordinate of the end point.
     * @since 1.2
     */
    public abstract double getY2();

    
Returns the end point.

Returns:a Point object that is the end point of this Point2D.
Since:1.2
/**
     * Returns the end point.
     * @return a {@code Point} object that is the end point
     *          of this {@code Point2D}.
     * @since 1.2
     */
    public abstract Point2D getP2();

    
Sets the location of the end points and control point of this curve to the specified double coordinates. 
Params:
  • x1 – the X coordinate of the start point
  • y1 – the Y coordinate of the start point
  • ctrlx – the X coordinate of the control point
  • ctrly – the Y coordinate of the control point
  • x2 – the X coordinate of the end point
  • y2 – the Y coordinate of the end point
Since:1.2
/**
     * Sets the location of the end points and control point of this curve
     * to the specified {@code double} coordinates.
     *
     * @param x1 the X coordinate of the start point
     * @param y1 the Y coordinate of the start point
     * @param ctrlx the X coordinate of the control point
     * @param ctrly the Y coordinate of the control point
     * @param x2 the X coordinate of the end point
     * @param y2 the Y coordinate of the end point
     * @since 1.2
     */
    public abstract void setCurve(double x1, double y1,
                                  double ctrlx, double ctrly,
                                  double x2, double y2);

    
Sets the location of the end points and control points of this QuadCurve2D to the double coordinates at the specified offset in the specified array. 
Params:
  • coords – the array containing coordinate values
  • offset – the index into the array from which to start getting the coordinate values and assigning them to this QuadCurve2D
Since:1.2
/**
     * Sets the location of the end points and control points of this
     * {@code QuadCurve2D} to the {@code double} coordinates at
     * the specified offset in the specified array.
     * @param coords the array containing coordinate values
     * @param offset the index into the array from which to start
     *          getting the coordinate values and assigning them to this
     *          {@code QuadCurve2D}
     * @since 1.2
     */
    public void setCurve(double[] coords, int offset) {
        setCurve(coords[offset + 0], coords[offset + 1],
                 coords[offset + 2], coords[offset + 3],
                 coords[offset + 4], coords[offset + 5]);
    }

    
Sets the location of the end points and control point of this QuadCurve2D to the specified Point2D coordinates. 
Params:
  • p1 – the start point
  • cp – the control point
  • p2 – the end point
Since:1.2
/**
     * Sets the location of the end points and control point of this
     * {@code QuadCurve2D} to the specified {@code Point2D}
     * coordinates.
     * @param p1 the start point
     * @param cp the control point
     * @param p2 the end point
     * @since 1.2
     */
    public void setCurve(Point2D p1, Point2D cp, Point2D p2) {
        setCurve(p1.getX(), p1.getY(),
                 cp.getX(), cp.getY(),
                 p2.getX(), p2.getY());
    }

    
Sets the location of the end points and control points of this QuadCurve2D to the coordinates of the Point2D objects at the specified offset in the specified array. 
Params:
  • pts – an array containing Point2D that define coordinate values
  • offset – the index into pts from which to start getting the coordinate values and assigning them to this QuadCurve2D
Since:1.2
/**
     * Sets the location of the end points and control points of this
     * {@code QuadCurve2D} to the coordinates of the
     * {@code Point2D} objects at the specified offset in
     * the specified array.
     * @param pts an array containing {@code Point2D} that define
     *          coordinate values
     * @param offset the index into {@code pts} from which to start
     *          getting the coordinate values and assigning them to this
     *          {@code QuadCurve2D}
     * @since 1.2
     */
    public void setCurve(Point2D[] pts, int offset) {
        setCurve(pts[offset + 0].getX(), pts[offset + 0].getY(),
                 pts[offset + 1].getX(), pts[offset + 1].getY(),
                 pts[offset + 2].getX(), pts[offset + 2].getY());
    }

    
Sets the location of the end points and control point of this QuadCurve2D to the same as those in the specified QuadCurve2D. 
Params:
  • c – the specified QuadCurve2D
Since:1.2
/**
     * Sets the location of the end points and control point of this
     * {@code QuadCurve2D} to the same as those in the specified
     * {@code QuadCurve2D}.
     * @param c the specified {@code QuadCurve2D}
     * @since 1.2
     */
    public void setCurve(QuadCurve2D c) {
        setCurve(c.getX1(), c.getY1(),
                 c.getCtrlX(), c.getCtrlY(),
                 c.getX2(), c.getY2());
    }

    
Returns the square of the flatness, or maximum distance of a
control point from the line connecting the end points, of the
quadratic curve specified by the indicated control points.

Params:
  • x1 – the X coordinate of the start point
  • y1 – the Y coordinate of the start point
  • ctrlx – the X coordinate of the control point
  • ctrly – the Y coordinate of the control point
  • x2 – the X coordinate of the end point
  • y2 – the Y coordinate of the end point
Returns:the square of the flatness of the quadratic curve
         defined by the specified coordinates.
Since:1.2
/**
     * Returns the square of the flatness, or maximum distance of a
     * control point from the line connecting the end points, of the
     * quadratic curve specified by the indicated control points.
     *
     * @param x1 the X coordinate of the start point
     * @param y1 the Y coordinate of the start point
     * @param ctrlx the X coordinate of the control point
     * @param ctrly the Y coordinate of the control point
     * @param x2 the X coordinate of the end point
     * @param y2 the Y coordinate of the end point
     * @return the square of the flatness of the quadratic curve
     *          defined by the specified coordinates.
     * @since 1.2
     */
    public static double getFlatnessSq(double x1, double y1,
                                       double ctrlx, double ctrly,
                                       double x2, double y2) {
        return Line2D.ptSegDistSq(x1, y1, x2, y2, ctrlx, ctrly);
    }

    
Returns the flatness, or maximum distance of a
control point from the line connecting the end points, of the
quadratic curve specified by the indicated control points.

Params:
  • x1 – the X coordinate of the start point
  • y1 – the Y coordinate of the start point
  • ctrlx – the X coordinate of the control point
  • ctrly – the Y coordinate of the control point
  • x2 – the X coordinate of the end point
  • y2 – the Y coordinate of the end point
Returns:the flatness of the quadratic curve defined by the
         specified coordinates.
Since:1.2
/**
     * Returns the flatness, or maximum distance of a
     * control point from the line connecting the end points, of the
     * quadratic curve specified by the indicated control points.
     *
     * @param x1 the X coordinate of the start point
     * @param y1 the Y coordinate of the start point
     * @param ctrlx the X coordinate of the control point
     * @param ctrly the Y coordinate of the control point
     * @param x2 the X coordinate of the end point
     * @param y2 the Y coordinate of the end point
     * @return the flatness of the quadratic curve defined by the
     *          specified coordinates.
     * @since 1.2
     */
    public static double getFlatness(double x1, double y1,
                                     double ctrlx, double ctrly,
                                     double x2, double y2) {
        return Line2D.ptSegDist(x1, y1, x2, y2, ctrlx, ctrly);
    }

    
Returns the square of the flatness, or maximum distance of a
control point from the line connecting the end points, of the
quadratic curve specified by the control points stored in the
indicated array at the indicated index.

Params:
  • coords – an array containing coordinate values
  • offset – the index into coords from which to to start getting the values from the array
Returns:the flatness of the quadratic curve that is defined by the
         values in the specified array at the specified index.
Since:1.2
/**
     * Returns the square of the flatness, or maximum distance of a
     * control point from the line connecting the end points, of the
     * quadratic curve specified by the control points stored in the
     * indicated array at the indicated index.
     * @param coords an array containing coordinate values
     * @param offset the index into {@code coords} from which to
     *          to start getting the values from the array
     * @return the flatness of the quadratic curve that is defined by the
     *          values in the specified array at the specified index.
     * @since 1.2
     */
    public static double getFlatnessSq(double coords[], int offset) {
        return Line2D.ptSegDistSq(coords[offset + 0], coords[offset + 1],
                                  coords[offset + 4], coords[offset + 5],
                                  coords[offset + 2], coords[offset + 3]);
    }

    
Returns the flatness, or maximum distance of a
control point from the line connecting the end points, of the
quadratic curve specified by the control points stored in the
indicated array at the indicated index.

Params:
  • coords – an array containing coordinate values
  • offset – the index into coords from which to start getting the coordinate values
Returns:the flatness of a quadratic curve defined by the
         specified array at the specified offset.
Since:1.2
/**
     * Returns the flatness, or maximum distance of a
     * control point from the line connecting the end points, of the
     * quadratic curve specified by the control points stored in the
     * indicated array at the indicated index.
     * @param coords an array containing coordinate values
     * @param offset the index into {@code coords} from which to
     *          start getting the coordinate values
     * @return the flatness of a quadratic curve defined by the
     *          specified array at the specified offset.
     * @since 1.2
     */
    public static double getFlatness(double coords[], int offset) {
        return Line2D.ptSegDist(coords[offset + 0], coords[offset + 1],
                                coords[offset + 4], coords[offset + 5],
                                coords[offset + 2], coords[offset + 3]);
    }

    
Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of this QuadCurve2D. 
Returns:the square of the flatness of this QuadCurve2D.
Since:1.2
/**
     * Returns the square of the flatness, or maximum distance of a
     * control point from the line connecting the end points, of this
     * {@code QuadCurve2D}.
     * @return the square of the flatness of this
     *          {@code QuadCurve2D}.
     * @since 1.2
     */
    public double getFlatnessSq() {
        return Line2D.ptSegDistSq(getX1(), getY1(),
                                  getX2(), getY2(),
                                  getCtrlX(), getCtrlY());
    }

    
Returns the flatness, or maximum distance of a control point from the line connecting the end points, of this QuadCurve2D. 
Returns:the flatness of this QuadCurve2D.
Since:1.2
/**
     * Returns the flatness, or maximum distance of a
     * control point from the line connecting the end points, of this
     * {@code QuadCurve2D}.
     * @return the flatness of this {@code QuadCurve2D}.
     * @since 1.2
     */
    public double getFlatness() {
        return Line2D.ptSegDist(getX1(), getY1(),
                                getX2(), getY2(),
                                getCtrlX(), getCtrlY());
    }

    
Subdivides this QuadCurve2D and stores the resulting two subdivided curves into the left and right curve parameters. Either or both of the left and right objects can be the same as this QuadCurve2D or null. 
Params:
  • left – the QuadCurve2D object for storing the left or first half of the subdivided curve
  • right – the QuadCurve2D object for storing the right or second half of the subdivided curve
Since:1.2
/**
     * Subdivides this {@code QuadCurve2D} and stores the resulting
     * two subdivided curves into the {@code left} and
     * {@code right} curve parameters.
     * Either or both of the {@code left} and {@code right}
     * objects can be the same as this {@code QuadCurve2D} or
     * {@code null}.
     * @param left the {@code QuadCurve2D} object for storing the
     * left or first half of the subdivided curve
     * @param right the {@code QuadCurve2D} object for storing the
     * right or second half of the subdivided curve
     * @since 1.2
     */
    public void subdivide(QuadCurve2D left, QuadCurve2D right) {
        subdivide(this, left, right);
    }

    
Subdivides the quadratic curve specified by the src parameter and stores the resulting two subdivided curves into the left and right curve parameters. Either or both of the left and right objects can be the same as the src object or null. 
Params:
  • src – the quadratic curve to be subdivided
  • left – the QuadCurve2D object for storing the left or first half of the subdivided curve
  • right – the QuadCurve2D object for storing the right or second half of the subdivided curve
Since:1.2
/**
     * Subdivides the quadratic curve specified by the {@code src}
     * parameter and stores the resulting two subdivided curves into the
     * {@code left} and {@code right} curve parameters.
     * Either or both of the {@code left} and {@code right}
     * objects can be the same as the {@code src} object or
     * {@code null}.
     * @param src the quadratic curve to be subdivided
     * @param left the {@code QuadCurve2D} object for storing the
     *          left or first half of the subdivided curve
     * @param right the {@code QuadCurve2D} object for storing the
     *          right or second half of the subdivided curve
     * @since 1.2
     */
    public static void subdivide(QuadCurve2D src,
                                 QuadCurve2D left,
                                 QuadCurve2D right) {
        double x1 = src.getX1();
        double y1 = src.getY1();
        double ctrlx = src.getCtrlX();
        double ctrly = src.getCtrlY();
        double x2 = src.getX2();
        double y2 = src.getY2();
        double ctrlx1 = (x1 + ctrlx) / 2.0;
        double ctrly1 = (y1 + ctrly) / 2.0;
        double ctrlx2 = (x2 + ctrlx) / 2.0;
        double ctrly2 = (y2 + ctrly) / 2.0;
        ctrlx = (ctrlx1 + ctrlx2) / 2.0;
        ctrly = (ctrly1 + ctrly2) / 2.0;
        if (left != null) {
            left.setCurve(x1, y1, ctrlx1, ctrly1, ctrlx, ctrly);
        }
        if (right != null) {
            right.setCurve(ctrlx, ctrly, ctrlx2, ctrly2, x2, y2);
        }
    }

    
Subdivides the quadratic curve specified by the coordinates stored in the src array at indices srcoff through srcoff + 5 and stores the resulting two subdivided curves into the two result arrays at the corresponding indices. Either or both of the left and right arrays can be null or a reference to the same array and offset as the src array. Note that the last point in the first subdivided curve is the same as the first point in the second subdivided curve. Thus, it is possible to pass the same array for left and right and to use offsets such that rightoff equals leftoff + 4 in order to avoid allocating extra storage for this common point. 
Params:
  • src – the array holding the coordinates for the source curve
  • srcoff – the offset into the array of the beginning of the
the 6 source coordinates
  • left – the array for storing the coordinates for the first
half of the subdivided curve
  • leftoff – the offset into the array of the beginning of the
the 6 left coordinates
  • right – the array for storing the coordinates for the second
half of the subdivided curve
  • rightoff – the offset into the array of the beginning of the
the 6 right coordinates
Since:1.2
/**
     * Subdivides the quadratic curve specified by the coordinates
     * stored in the {@code src} array at indices
     * {@code srcoff} through {@code srcoff}&nbsp;+&nbsp;5
     * and stores the resulting two subdivided curves into the two
     * result arrays at the corresponding indices.
     * Either or both of the {@code left} and {@code right}
     * arrays can be {@code null} or a reference to the same array
     * and offset as the {@code src} array.
     * Note that the last point in the first subdivided curve is the
     * same as the first point in the second subdivided curve.  Thus,
     * it is possible to pass the same array for {@code left} and
     * {@code right} and to use offsets such that
     * {@code rightoff} equals {@code leftoff} + 4 in order
     * to avoid allocating extra storage for this common point.
     * @param src the array holding the coordinates for the source curve
     * @param srcoff the offset into the array of the beginning of the
     * the 6 source coordinates
     * @param left the array for storing the coordinates for the first
     * half of the subdivided curve
     * @param leftoff the offset into the array of the beginning of the
     * the 6 left coordinates
     * @param right the array for storing the coordinates for the second
     * half of the subdivided curve
     * @param rightoff the offset into the array of the beginning of the
     * the 6 right coordinates
     * @since 1.2
     */
    public static void subdivide(double src[], int srcoff,
                                 double left[], int leftoff,
                                 double right[], int rightoff) {
        double x1 = src[srcoff + 0];
        double y1 = src[srcoff + 1];
        double ctrlx = src[srcoff + 2];
        double ctrly = src[srcoff + 3];
        double x2 = src[srcoff + 4];
        double y2 = src[srcoff + 5];
        if (left != null) {
            left[leftoff + 0] = x1;
            left[leftoff + 1] = y1;
        }
        if (right != null) {
            right[rightoff + 4] = x2;
            right[rightoff + 5] = y2;
        }
        x1 = (x1 + ctrlx) / 2.0;
        y1 = (y1 + ctrly) / 2.0;
        x2 = (x2 + ctrlx) / 2.0;
        y2 = (y2 + ctrly) / 2.0;
        ctrlx = (x1 + x2) / 2.0;
        ctrly = (y1 + y2) / 2.0;
        if (left != null) {
            left[leftoff + 2] = x1;
            left[leftoff + 3] = y1;
            left[leftoff + 4] = ctrlx;
            left[leftoff + 5] = ctrly;
        }
        if (right != null) {
            right[rightoff + 0] = ctrlx;
            right[rightoff + 1] = ctrly;
            right[rightoff + 2] = x2;
            right[rightoff + 3] = y2;
        }
    }

    
Solves the quadratic whose coefficients are in the eqn array and places the non-complex roots back into the same array, returning the number of roots. The quadratic solved is represented by the equation: 
    eqn = {C, B, A};
    ax^2 + bx + c = 0

 A return value of -1 is used to distinguish a constant equation, which might be always 0 or never 0, from an equation that has no zeroes. 
Params:
  • eqn – the array that contains the quadratic coefficients
Returns:the number of roots, or -1 if the equation is a constant
Since:1.2
/**
     * Solves the quadratic whose coefficients are in the {@code eqn}
     * array and places the non-complex roots back into the same array,
     * returning the number of roots.  The quadratic solved is represented
     * by the equation:
     * <pre>
     *     eqn = {C, B, A};
     *     ax^2 + bx + c = 0
     * </pre>
     * A return value of {@code -1} is used to distinguish a constant
     * equation, which might be always 0 or never 0, from an equation that
     * has no zeroes.
     * @param eqn the array that contains the quadratic coefficients
     * @return the number of roots, or {@code -1} if the equation is
     *          a constant
     * @since 1.2
     */
    public static int solveQuadratic(double eqn[]) {
        return solveQuadratic(eqn, eqn);
    }

    
Solves the quadratic whose coefficients are in the eqn array and places the non-complex roots into the res array, returning the number of roots. The quadratic solved is represented by the equation: 
    eqn = {C, B, A};
    ax^2 + bx + c = 0

 A return value of -1 is used to distinguish a constant equation, which might be always 0 or never 0, from an equation that has no zeroes. 
Params:
  • eqn – the specified array of coefficients to use to solve
       the quadratic equation
  • res – the array that contains the non-complex roots
       resulting from the solution of the quadratic equation
Returns:the number of roots, or -1 if the equation is a constant.
Since:1.3
/**
     * Solves the quadratic whose coefficients are in the {@code eqn}
     * array and places the non-complex roots into the {@code res}
     * array, returning the number of roots.
     * The quadratic solved is represented by the equation:
     * <pre>
     *     eqn = {C, B, A};
     *     ax^2 + bx + c = 0
     * </pre>
     * A return value of {@code -1} is used to distinguish a constant
     * equation, which might be always 0 or never 0, from an equation that
     * has no zeroes.
     * @param eqn the specified array of coefficients to use to solve
     *        the quadratic equation
     * @param res the array that contains the non-complex roots
     *        resulting from the solution of the quadratic equation
     * @return the number of roots, or {@code -1} if the equation is
     *  a constant.
     * @since 1.3
     */
    public static int solveQuadratic(double eqn[], double res[]) {
        double a = eqn[2];
        double b = eqn[1];
        double c = eqn[0];
        int roots = 0;
        if (a == 0.0) {
            // The quadratic parabola has degenerated to a line.
            if (b == 0.0) {
                // The line has degenerated to a constant.
                return -1;
            }
            res[roots++] = -c / b;
        } else {
            // From Numerical Recipes, 5.6, Quadratic and Cubic Equations
            double d = b * b - 4.0 * a * c;
            if (d < 0.0) {
                // If d < 0.0, then there are no roots
                return 0;
            }
            d = Math.sqrt(d);
            // For accuracy, calculate one root using:
            //     (-b +/- d) / 2a
            // and the other using:
            //     2c / (-b +/- d)
            // Choose the sign of the +/- so that b+d gets larger in magnitude
            if (b < 0.0) {
                d = -d;
            }
            double q = (b + d) / -2.0;
            // We already tested a for being 0 above
            res[roots++] = q / a;
            if (q != 0.0) {
                res[roots++] = c / q;
            }
        }
        return roots;
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean contains(double x, double y) {

        double x1 = getX1();
        double y1 = getY1();
        double xc = getCtrlX();
        double yc = getCtrlY();
        double x2 = getX2();
        double y2 = getY2();

        /*
         * We have a convex shape bounded by quad curve Pc(t)
         * and ine Pl(t).
         *
         *     P1 = (x1, y1) - start point of curve
         *     P2 = (x2, y2) - end point of curve
         *     Pc = (xc, yc) - control point
         *
         *     Pq(t) = P1*(1 - t)^2 + 2*Pc*t*(1 - t) + P2*t^2 =
         *           = (P1 - 2*Pc + P2)*t^2 + 2*(Pc - P1)*t + P1
         *     Pl(t) = P1*(1 - t) + P2*t
         *     t = [0:1]
         *
         *     P = (x, y) - point of interest
         *
         * Let's look at second derivative of quad curve equation:
         *
         *     Pq''(t) = 2 * (P1 - 2 * Pc + P2) = Pq''
         *     It's constant vector.
         *
         * Let's draw a line through P to be parallel to this
         * vector and find the intersection of the quad curve
         * and the line.
         *
         * Pq(t) is point of intersection if system of equations
         * below has the solution.
         *
         *     L(s) = P + Pq''*s == Pq(t)
         *     Pq''*s + (P - Pq(t)) == 0
         *
         *     | xq''*s + (x - xq(t)) == 0
         *     | yq''*s + (y - yq(t)) == 0
         *
         * This system has the solution if rank of its matrix equals to 1.
         * That is, determinant of the matrix should be zero.
         *
         *     (y - yq(t))*xq'' == (x - xq(t))*yq''
         *
         * Let's solve this equation with 't' variable.
         * Also let kx = x1 - 2*xc + x2
         *          ky = y1 - 2*yc + y2
         *
         *     t0q = (1/2)*((x - x1)*ky - (y - y1)*kx) /
         *                 ((xc - x1)*ky - (yc - y1)*kx)
         *
         * Let's do the same for our line Pl(t):
         *
         *     t0l = ((x - x1)*ky - (y - y1)*kx) /
         *           ((x2 - x1)*ky - (y2 - y1)*kx)
         *
         * It's easy to check that t0q == t0l. This fact means
         * we can compute t0 only one time.
         *
         * In case t0 < 0 or t0 > 1, we have an intersections outside
         * of shape bounds. So, P is definitely out of shape.
         *
         * In case t0 is inside [0:1], we should calculate Pq(t0)
         * and Pl(t0). We have three points for now, and all of them
         * lie on one line. So, we just need to detect, is our point
         * of interest between points of intersections or not.
         *
         * If the denominator in the t0q and t0l equations is
         * zero, then the points must be collinear and so the
         * curve is degenerate and encloses no area.  Thus the
         * result is false.
         */
        double kx = x1 - 2 * xc + x2;
        double ky = y1 - 2 * yc + y2;
        double dx = x - x1;
        double dy = y - y1;
        double dxl = x2 - x1;
        double dyl = y2 - y1;

        double t0 = (dx * ky - dy * kx) / (dxl * ky - dyl * kx);
        if (t0 < 0 || t0 > 1 || t0 != t0) {
            return false;
        }

        double xb = kx * t0 * t0 + 2 * (xc - x1) * t0 + x1;
        double yb = ky * t0 * t0 + 2 * (yc - y1) * t0 + y1;
        double xl = dxl * t0 + x1;
        double yl = dyl * t0 + y1;

        return (x >= xb && x < xl) ||
               (x >= xl && x < xb) ||
               (y >= yb && y < yl) ||
               (y >= yl && y < yb);
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean contains(Point2D p) {
        return contains(p.getX(), p.getY());
    }

    
Fill an array with the coefficients of the parametric equation
in t, ready for solving against val with solveQuadratic.
We currently have:
    val = Py(t) = C1*(1-t)^2 + 2*CP*t*(1-t) + C2*t^2
                = C1 - 2*C1*t + C1*t^2 + 2*CP*t - 2*CP*t^2 + C2*t^2
                = C1 + (2*CP - 2*C1)*t + (C1 - 2*CP + C2)*t^2
              0 = (C1 - val) + (2*CP - 2*C1)*t + (C1 - 2*CP + C2)*t^2
              0 = C + Bt + At^2
    C = C1 - val
    B = 2*CP - 2*C1
    A = C1 - 2*CP + C2

/**
     * Fill an array with the coefficients of the parametric equation
     * in t, ready for solving against val with solveQuadratic.
     * We currently have:
     *     val = Py(t) = C1*(1-t)^2 + 2*CP*t*(1-t) + C2*t^2
     *                 = C1 - 2*C1*t + C1*t^2 + 2*CP*t - 2*CP*t^2 + C2*t^2
     *                 = C1 + (2*CP - 2*C1)*t + (C1 - 2*CP + C2)*t^2
     *               0 = (C1 - val) + (2*CP - 2*C1)*t + (C1 - 2*CP + C2)*t^2
     *               0 = C + Bt + At^2
     *     C = C1 - val
     *     B = 2*CP - 2*C1
     *     A = C1 - 2*CP + C2
     */
    private static void fillEqn(double eqn[], double val,
                                double c1, double cp, double c2) {
        eqn[0] = c1 - val;
        eqn[1] = cp + cp - c1 - c1;
        eqn[2] = c1 - cp - cp + c2;
        return;
    }

    
Evaluate the t values in the first num slots of the vals[] array
and place the evaluated values back into the same array.  Only
evaluate t values that are within the range <0, 1>, including
the 0 and 1 ends of the range iff the include0 or include1
booleans are true.  If an "inflection" equation is handed in,
then any points which represent a point of inflection for that
quadratic equation are also ignored.

/**
     * Evaluate the t values in the first num slots of the vals[] array
     * and place the evaluated values back into the same array.  Only
     * evaluate t values that are within the range &lt;0, 1&gt;, including
     * the 0 and 1 ends of the range iff the include0 or include1
     * booleans are true.  If an "inflection" equation is handed in,
     * then any points which represent a point of inflection for that
     * quadratic equation are also ignored.
     */
    private static int evalQuadratic(double vals[], int num,
                                     boolean include0,
                                     boolean include1,
                                     double inflect[],
                                     double c1, double ctrl, double c2) {
        int j = 0;
        for (int i = 0; i < num; i++) {
            double t = vals[i];
            if ((include0 ? t >= 0 : t > 0) &&
                (include1 ? t <= 1 : t < 1) &&
                (inflect == null ||
                 inflect[1] + 2*inflect[2]*t != 0))
            {
                double u = 1 - t;
                vals[j++] = c1*u*u + 2*ctrl*t*u + c2*t*t;
            }
        }
        return j;
    }

    private static final int BELOW = -2;
    private static final int LOWEDGE = -1;
    private static final int INSIDE = 0;
    private static final int HIGHEDGE = 1;
    private static final int ABOVE = 2;

    
Determine where coord lies with respect to the range from
low to high.  It is assumed that low <= high.  The return
value is one of the 5 values BELOW, LOWEDGE, INSIDE, HIGHEDGE,
or ABOVE.

/**
     * Determine where coord lies with respect to the range from
     * low to high.  It is assumed that low &lt;= high.  The return
     * value is one of the 5 values BELOW, LOWEDGE, INSIDE, HIGHEDGE,
     * or ABOVE.
     */
    private static int getTag(double coord, double low, double high) {
        if (coord <= low) {
            return (coord < low ? BELOW : LOWEDGE);
        }
        if (coord >= high) {
            return (coord > high ? ABOVE : HIGHEDGE);
        }
        return INSIDE;
    }

    
Determine if the pttag represents a coordinate that is already
in its test range, or is on the border with either of the two
opttags representing another coordinate that is "towards the
inside" of that test range.  In other words, are either of the
two "opt" points "drawing the pt inward"?

/**
     * Determine if the pttag represents a coordinate that is already
     * in its test range, or is on the border with either of the two
     * opttags representing another coordinate that is "towards the
     * inside" of that test range.  In other words, are either of the
     * two "opt" points "drawing the pt inward"?
     */
    private static boolean inwards(int pttag, int opt1tag, int opt2tag) {
        switch (pttag) {
        case BELOW:
        case ABOVE:
        default:
            return false;
        case LOWEDGE:
            return (opt1tag >= INSIDE || opt2tag >= INSIDE);
        case INSIDE:
            return true;
        case HIGHEDGE:
            return (opt1tag <= INSIDE || opt2tag <= INSIDE);
        }
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean intersects(double x, double y, double w, double h) {
        // Trivially reject non-existant rectangles
        if (w <= 0 || h <= 0) {
            return false;
        }

        // Trivially accept if either endpoint is inside the rectangle
        // (not on its border since it may end there and not go inside)
        // Record where they lie with respect to the rectangle.
        //     -1 => left, 0 => inside, 1 => right
        double x1 = getX1();
        double y1 = getY1();
        int x1tag = getTag(x1, x, x+w);
        int y1tag = getTag(y1, y, y+h);
        if (x1tag == INSIDE && y1tag == INSIDE) {
            return true;
        }
        double x2 = getX2();
        double y2 = getY2();
        int x2tag = getTag(x2, x, x+w);
        int y2tag = getTag(y2, y, y+h);
        if (x2tag == INSIDE && y2tag == INSIDE) {
            return true;
        }
        double ctrlx = getCtrlX();
        double ctrly = getCtrlY();
        int ctrlxtag = getTag(ctrlx, x, x+w);
        int ctrlytag = getTag(ctrly, y, y+h);

        // Trivially reject if all points are entirely to one side of
        // the rectangle.
        if (x1tag < INSIDE && x2tag < INSIDE && ctrlxtag < INSIDE) {
            return false;       // All points left
        }
        if (y1tag < INSIDE && y2tag < INSIDE && ctrlytag < INSIDE) {
            return false;       // All points above
        }
        if (x1tag > INSIDE && x2tag > INSIDE && ctrlxtag > INSIDE) {
            return false;       // All points right
        }
        if (y1tag > INSIDE && y2tag > INSIDE && ctrlytag > INSIDE) {
            return false;       // All points below
        }

        // Test for endpoints on the edge where either the segment
        // or the curve is headed "inwards" from them
        // Note: These tests are a superset of the fast endpoint tests
        //       above and thus repeat those tests, but take more time
        //       and cover more cases
        if (inwards(x1tag, x2tag, ctrlxtag) &&
            inwards(y1tag, y2tag, ctrlytag))
        {
            // First endpoint on border with either edge moving inside
            return true;
        }
        if (inwards(x2tag, x1tag, ctrlxtag) &&
            inwards(y2tag, y1tag, ctrlytag))
        {
            // Second endpoint on border with either edge moving inside
            return true;
        }

        // Trivially accept if endpoints span directly across the rectangle
        boolean xoverlap = (x1tag * x2tag <= 0);
        boolean yoverlap = (y1tag * y2tag <= 0);
        if (x1tag == INSIDE && x2tag == INSIDE && yoverlap) {
            return true;
        }
        if (y1tag == INSIDE && y2tag == INSIDE && xoverlap) {
            return true;
        }

        // We now know that both endpoints are outside the rectangle
        // but the 3 points are not all on one side of the rectangle.
        // Therefore the curve cannot be contained inside the rectangle,
        // but the rectangle might be contained inside the curve, or
        // the curve might intersect the boundary of the rectangle.

        double[] eqn = new double[3];
        double[] res = new double[3];
        if (!yoverlap) {
            // Both Y coordinates for the closing segment are above or
            // below the rectangle which means that we can only intersect
            // if the curve crosses the top (or bottom) of the rectangle
            // in more than one place and if those crossing locations
            // span the horizontal range of the rectangle.
            fillEqn(eqn, (y1tag < INSIDE ? y : y+h), y1, ctrly, y2);
            return (solveQuadratic(eqn, res) == 2 &&
                    evalQuadratic(res, 2, true, true, null,
                                  x1, ctrlx, x2) == 2 &&
                    getTag(res[0], x, x+w) * getTag(res[1], x, x+w) <= 0);
        }

        // Y ranges overlap.  Now we examine the X ranges
        if (!xoverlap) {
            // Both X coordinates for the closing segment are left of
            // or right of the rectangle which means that we can only
            // intersect if the curve crosses the left (or right) edge
            // of the rectangle in more than one place and if those
            // crossing locations span the vertical range of the rectangle.
            fillEqn(eqn, (x1tag < INSIDE ? x : x+w), x1, ctrlx, x2);
            return (solveQuadratic(eqn, res) == 2 &&
                    evalQuadratic(res, 2, true, true, null,
                                  y1, ctrly, y2) == 2 &&
                    getTag(res[0], y, y+h) * getTag(res[1], y, y+h) <= 0);
        }

        // The X and Y ranges of the endpoints overlap the X and Y
        // ranges of the rectangle, now find out how the endpoint
        // line segment intersects the Y range of the rectangle
        double dx = x2 - x1;
        double dy = y2 - y1;
        double k = y2 * x1 - x2 * y1;
        int c1tag, c2tag;
        if (y1tag == INSIDE) {
            c1tag = x1tag;
        } else {
            c1tag = getTag((k + dx * (y1tag < INSIDE ? y : y+h)) / dy, x, x+w);
        }
        if (y2tag == INSIDE) {
            c2tag = x2tag;
        } else {
            c2tag = getTag((k + dx * (y2tag < INSIDE ? y : y+h)) / dy, x, x+w);
        }
        // If the part of the line segment that intersects the Y range
        // of the rectangle crosses it horizontally - trivially accept
        if (c1tag * c2tag <= 0) {
            return true;
        }

        // Now we know that both the X and Y ranges intersect and that
        // the endpoint line segment does not directly cross the rectangle.
        //
        // We can almost treat this case like one of the cases above
        // where both endpoints are to one side, except that we will
        // only get one intersection of the curve with the vertical
        // side of the rectangle.  This is because the endpoint segment
        // accounts for the other intersection.
        //
        // (Remember there is overlap in both the X and Y ranges which
        //  means that the segment must cross at least one vertical edge
        //  of the rectangle - in particular, the "near vertical side" -
        //  leaving only one intersection for the curve.)
        //
        // Now we calculate the y tags of the two intersections on the
        // "near vertical side" of the rectangle.  We will have one with
        // the endpoint segment, and one with the curve.  If those two
        // vertical intersections overlap the Y range of the rectangle,
        // we have an intersection.  Otherwise, we don't.

        // c1tag = vertical intersection class of the endpoint segment
        //
        // Choose the y tag of the endpoint that was not on the same
        // side of the rectangle as the subsegment calculated above.
        // Note that we can "steal" the existing Y tag of that endpoint
        // since it will be provably the same as the vertical intersection.
        c1tag = ((c1tag * x1tag <= 0) ? y1tag : y2tag);

        // c2tag = vertical intersection class of the curve
        //
        // We have to calculate this one the straightforward way.
        // Note that the c2tag can still tell us which vertical edge
        // to test against.
        fillEqn(eqn, (c2tag < INSIDE ? x : x+w), x1, ctrlx, x2);
        int num = solveQuadratic(eqn, res);

        // Note: We should be able to assert(num == 2); since the
        // X range "crosses" (not touches) the vertical boundary,
        // but we pass num to evalQuadratic for completeness.
        evalQuadratic(res, num, true, true, null, y1, ctrly, y2);

        // Note: We can assert(num evals == 1); since one of the
        // 2 crossings will be out of the [0,1] range.
        c2tag = getTag(res[0], y, y+h);

        // Finally, we have an intersection if the two crossings
        // overlap the Y range of the rectangle.
        return (c1tag * c2tag <= 0);
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean intersects(Rectangle2D r) {
        return intersects(r.getX(), r.getY(), r.getWidth(), r.getHeight());
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean contains(double x, double y, double w, double h) {
        if (w <= 0 || h <= 0) {
            return false;
        }
        // Assertion: Quadratic curves closed by connecting their
        // endpoints are always convex.
        return (contains(x, y) &&
                contains(x + w, y) &&
                contains(x + w, y + h) &&
                contains(x, y + h));
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean contains(Rectangle2D r) {
        return contains(r.getX(), r.getY(), r.getWidth(), r.getHeight());
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public Rectangle getBounds() {
        return getBounds2D().getBounds();
    }

    
Returns an iteration object that defines the boundary of the shape of this QuadCurve2D. The iterator for this class is not multi-threaded safe, which means that this QuadCurve2D class does not guarantee that modifications to the geometry of this QuadCurve2D object do not affect any iterations of that geometry that are already in process. 
Params:
Returns:a PathIterator object that defines the boundary of the shape.
Since:1.2
/**
     * Returns an iteration object that defines the boundary of the
     * shape of this {@code QuadCurve2D}.
     * The iterator for this class is not multi-threaded safe,
     * which means that this {@code QuadCurve2D} class does not
     * guarantee that modifications to the geometry of this
     * {@code QuadCurve2D} object do not affect any iterations of
     * that geometry that are already in process.
     * @param at an optional {@link AffineTransform} to apply to the
     *          shape boundary
     * @return a {@link PathIterator} object that defines the boundary
     *          of the shape.
     * @since 1.2
     */
    public PathIterator getPathIterator(AffineTransform at) {
        return new QuadIterator(this, at);
    }

    
Returns an iteration object that defines the boundary of the flattened shape of this QuadCurve2D. The iterator for this class is not multi-threaded safe, which means that this QuadCurve2D class does not guarantee that modifications to the geometry of this QuadCurve2D object do not affect any iterations of that geometry that are already in process. 
Params:
  • at – an optional AffineTransform to apply to the boundary of the shape
  • flatness – the maximum distance that the control points for a
         subdivided curve can be with respect to a line connecting
         the end points of this curve before this curve is
         replaced by a straight line connecting the end points.
Returns:a PathIterator object that defines the flattened boundary of the shape.
Since:1.2
/**
     * Returns an iteration object that defines the boundary of the
     * flattened shape of this {@code QuadCurve2D}.
     * The iterator for this class is not multi-threaded safe,
     * which means that this {@code QuadCurve2D} class does not
     * guarantee that modifications to the geometry of this
     * {@code QuadCurve2D} object do not affect any iterations of
     * that geometry that are already in process.
     * @param at an optional {@code AffineTransform} to apply
     *          to the boundary of the shape
     * @param flatness the maximum distance that the control points for a
     *          subdivided curve can be with respect to a line connecting
     *          the end points of this curve before this curve is
     *          replaced by a straight line connecting the end points.
     * @return a {@code PathIterator} object that defines the
     *          flattened boundary of the shape.
     * @since 1.2
     */
    public PathIterator getPathIterator(AffineTransform at, double flatness) {
        return new FlatteningPathIterator(getPathIterator(at), flatness);
    }

    
Creates a new object of the same class and with the same contents
as this object.

Throws:
See Also:
Returns:    a clone of this instance.
Since:     1.2
/**
     * Creates a new object of the same class and with the same contents
     * as this object.
     *
     * @return     a clone of this instance.
     * @exception  OutOfMemoryError            if there is not enough memory.
     * @see        java.lang.Cloneable
     * @since      1.2
     */
    public Object clone() {
        try {
            return super.clone();
        } catch (CloneNotSupportedException e) {
            // this shouldn't happen, since we are Cloneable
            throw new InternalError(e);
        }
    }
}