quadcurve2d.java

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/*
 * @(#)QuadCurve2D.java	1.27 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.awt.geom;

import java.awt.Shape;
import java.awt.Rectangle;

/**
 * The <code>QuadCurve2D</code> class defines a quadratic parametric curve
 * segment in (x,&nbsp;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.
 *
 * @version 	1.27, 01/23/03
 * @author	Jim Graham
 */
public abstract class QuadCurve2D implements Shape, Cloneable {
    /**
     * A quadratic parametric curve segment specified with 
     * <code>float</code> coordinates.
     */

    public static class Float extends QuadCurve2D {

	/**
	 * The x coordinate of the start point of the quadratic curve
         * segment.
	 */
	public float x1;

	/**
	 * The y coordinate of the start point of the quadratic curve
         * segment.
	 */
	public float y1;

	/**
	 * The x coordinate of the control point of the quadratic curve
         * segment.
	 */
	public float ctrlx;

	/**
	 * The y coordinate of the control point of the quadratic curve
         * segment.
	 */
	public float ctrly;

	/**
	 * The x coordinate of the end point of the quadratic curve
         * segment.
	 */
	public float x2;

	/**
	 * The y coordinate of the end point of the quadratic curve
         * segment.
	 */
	public float y2;

	/**
	 * Constructs and initializes a <code>QuadCurve2D</code> with
         * coordinates (0, 0, 0, 0, 0, 0).
	 */
	public Float() {
	}

	/**
	 * Constructs and initializes a <code>QuadCurve2D</code> from the
         * specified coordinates.
         * @param x1,&nbsp;y1 the starting point coordinates
         * @param ctrlx,&nbsp;ctrly the coordinates of the control point
         * @param x2,&nbsp;y2 the ending point coordinates
	 */
	public Float(float x1, float y1,
		     float ctrlx, float ctrly,
		     float x2, float y2) {
	    setCurve(x1, y1, ctrlx, ctrly, x2, y2);
	}

	/**
	 * Returns the x coordinate of the start point in 
         * <code>double</code> precision.
         * @return the x coordinate of the starting point.
	 */
	public double getX1() {
	    return (double) x1;
	}

	/**
	 * Returns the y coordinate of the start point in 
         * <code>double</code> precision.
         * @return the y coordinate of the starting point.
	 */
	public double getY1() {
	    return (double) y1;
	}

	/**
	 * Returns the start point.
         * @return a {@link Point2D} object that is the starting point
         *		of this <code>QuadCurve2D</code>.
	 */
	public Point2D getP1() {
	    return new Point2D.Float(x1, y1);
	}

	/**
	 * Returns the x coordinate of the control point in 
         * <code>double</code> precision.
         * @return the x coordinate of the control point.
	 */
	public double getCtrlX() {
	    return (double) ctrlx;
	}

	/**
	 * Returns the y coordinate of the control point in 
         * <code>double</code> precision.
         * @return the y coordiante of the control point.
	 */
	public double getCtrlY() {
	    return (double) ctrly;
	}

	/**
	 * Returns the control point.
         * @return a <code>Point2D</code> that is the control point of
         *	this <code>QuadCurve2D</code>.
	 */
	public Point2D getCtrlPt() {
	    return new Point2D.Float(ctrlx, ctrly);
	}

	/**
	 * Returns the x coordinate of the end point in 
         * <code>double</code> precision.
         * @return the x coordinate of the end point.
	 */
	public double getX2() {
	    return (double) x2;
	}

	/**
	 * Returns the y coordinate of the end point in 
         * <code>double</code> precision.
         * @return the y coordiante of the end point.
	 */
	public double getY2() {
	    return (double) y2;
	}

	/**
	 * Returns the end point.
         * @return a <code>Point2D</code> that is the end point of this
         * 		<code>QuadCurve2D</code>.
	 */
	public Point2D getP2() {
	    return new Point2D.Float(x2, y2);
	}

	/**
	 * Sets the location of the endpoints and controlpoint of this 
         * <code>QuadCurve2D</code> to the specified <code>double</code>
         * coordinates.
         * @param x1,&nbsp;y1 the coordinates of the starting point
         * @param ctrlx,&nbsp;ctrly the coordinates of the control point
         * @param x2,&nbsp;y2 the coordinates of the ending point
	 */
	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 endpoints and controlpoint of this curve
	 * to the specified <code>float</code> coordinates.
         * @param x1,&nbsp;y1 the coordinates of the starting point
         * @param ctrlx,&nbsp;ctrly the coordinates of the control point
         * @param x2,&nbsp;y2 the coordinates of the ending point
	 */
	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;
	}

	/**
	 * Returns the bounding box of this <code>QuadCurve2D</code>.
         * @return a {@link Rectangle2D} that is the bounding box
         *		of the shape of this <code>QuadCurve2D</code>.
	 */
	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);
	}
    }

    /**
     * A quadratic parametric curve segment specified with 
     * <code>double</code> coordinates.
     */
    public static class Double extends QuadCurve2D {
	/**
	 * The x coordinate of the start point of the quadratic curve
         * segment.
	 */
	public double x1;

	/**
	 * The x coordinate of the start point of the quadratic curve
         * segment.
	 */
	public double y1;

	/**
	 * The x coordinate of the control point of the quadratic curve
         * segment.
	 */
	public double ctrlx;

	/**
	 * The y coordinate of the control point of the quadratic curve
         * segment.
	 */
	public double ctrly;

	/**
	 * The x coordinate of the end point of the quadratic curve
         * segment.
	 */
	public double x2;

	/**
	 * The y coordinate of the end point of the quadratic curve
         * segment.
	 */
	public double y2;

	/**
	 * Constructs and initializes a <code>QuadCurve2D</code> with
         * coordinates (0, 0, 0, 0, 0, 0).
	 */
	public Double() {
	}

	/**
	 * Constructs and initializes a <code>QuadCurve2D</code> from the
         * specified coordinates.
         * @param x1,&nbsp;y1 the coordinates of the starting point
         * @param ctrlx,&nbsp;ctrly the coordinates of the control point
         * @param x2,&nbsp;y2 the coordinates of the ending point
	 */
	public Double(double x1, double y1,
		      double ctrlx, double ctrly,
		      double x2, double y2) {
	    setCurve(x1, y1, ctrlx, ctrly, x2, y2);
	}

	/**
	 * Returns the x coordinate of the start point in 
         * <code>double</code> precision.
         * @return the x coordinate of the starting point.
	 */
	public double getX1() {
	    return x1;
	}

	/**
	 * Returns the y coordinate of the start point in 
         * <code>double</code> precision.
         * @return the y coordiante of the starting point.
	 */
	public double getY1() {
	    return y1;
	}

	/**
	 * Returns the start point.
         * @return a <code>Point2D</code> that is the starting point
         *		of this <code>QuadCurve2D</code>.
	 */
	public Point2D getP1() {
	    return new Point2D.Double(x1, y1);
	}

	/**
	 * Returns the x coordinate of the control point in 
         * <code>double</code> precision.
         * @return the x coordinate of the control point.
	 */
	public double getCtrlX() {
	    return ctrlx;
	}

	/**
	 * Returns the y coordinate of the control point in 
         * <code>double</code> precision.
         * @return the y coordiante of the control point.
	 */
	public double getCtrlY() {
	    return ctrly;
	}

	/**
	 * Returns the control point.
         * @return a <code>Point2D</code> object that is the control
         * point of this <code>QuadCurve2D</code>. 
	 */
	public Point2D getCtrlPt() {
	    return new Point2D.Double(ctrlx, ctrly);
	}

	/**
	 * Returns the x coordinate of the end point in 
         * <code>double</code> precision.
         * @return the x coordiante of the end point.
	 */
	public double getX2() {
	    return x2;
	}

	/**
	 * Returns the y coordinate of the end point in 
         * <code>double</code> precision.
         * @return the y coordiante of the end point.
	 */
	public double getY2() {
	    return y2;
	}

	/**
	 * Returns the end point.
         * @return a <code>Point2D</code> that is the end point
         *	of this <code>QuadCurve2D</code>.
	 */
	public Point2D getP2() {
	    return new Point2D.Double(x2, y2);
	}

	/**
	 * Sets the location of the endpoints and controlpoint of this curve
	 * to the specified <code>double</code> coordinates.
         * @param x1,&nbsp;y1 the coordinates of the starting point
         * @param ctrlx,&nbsp;ctrly the coordinates of the control point
         * @param x2,&nbsp;y2 the coordinates of the ending point
	 */
	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;
	}

	/**
	 * Returns the bounding box of this <code>QuadCurve2D</code>.
         * @return a <code>Rectangle2D</code> that is the bounding
         * 	box of the shape of this <code>QuadCurve2D</code>.
	 */
	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);
	}
    }

    /**
     * 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
     */
    protected QuadCurve2D() {
    }

    /**
     * Returns the x coordinate of the start point in 
     * <code>double</code> in precision.
     * @return the x coordinate of the start point.
     */
    public abstract double getX1();

    /**
     * Returns the y coordinate of the start point in 
     * <code>double</code> precision.
     * @return the y coordinate of the start point.
     */
    public abstract double getY1();

    /**
     * Returns the start point.
     * @return a <code>Point2D</code> that is the start point of this
     * 		<code>QuadCurve2D</code>.
     */