rectangle2d.java

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/*
 * @(#)Rectangle2D.java	1.28 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.awt.geom;

/**
 * The <code>Rectangle2D</code> class describes a rectangle
 * defined by a location (x,&nbsp;y) and dimension 
 * (w&nbsp;x&nbsp;h).
 * <p>
 * This class is only the abstract superclass for all objects that
 * store a 2D rectangle.
 * The actual storage representation of the coordinates is left to
 * the subclass.
 *
 * @version 	1.28, 01/23/03
 * @author	Jim Graham
 */
public abstract class Rectangle2D extends RectangularShape {
    /**
     * The bitmask that indicates that a point lies to the left of
     * this <code>Rectangle2D</code>.
     * @since 1.2
     */
    public static final int OUT_LEFT = 1;

    /**
     * The bitmask that indicates that a point lies above
     * this <code>Rectangle2D</code>.
     * @since 1.2
     */
    public static final int OUT_TOP = 2;

    /**
     * The bitmask that indicates that a point lies to the right of
     * this <code>Rectangle2D</code>.
     * @since 1.2
     */
    public static final int OUT_RIGHT = 4;

    /**
     * The bitmask that indicates that a point lies below
     * this <code>Rectangle2D</code>.
     * @since 1.2
     */
    public static final int OUT_BOTTOM = 8;

    /**
     * The <code>Float</code> class defines a rectangle specified in float
     * coordinates.
     * @since 1.2
     */
    public static class Float extends Rectangle2D {
	/**
	 * The x coordinate of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public float x;

	/**
	 * The y coordinate of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public float y;

	/**
	 * The width of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public float width;

	/**
	 * The height of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public float height;

	/**
	 * Constructs a new <code>Rectangle2D</code>, initialized to
         * location (0.0,&nbsp;0.0) and size (0.0,&nbsp;0.0).
	 * @since 1.2
	 */
	public Float() {
	}

	/**
	 * Constructs and initializes a <code>Rectangle2D</code> 
         * from the specified float coordinates.
	 * @param x,&nbsp;y the coordinates of the
         * upper left corner of the newly constructed
         * <code>Rectangle2D</code>
	 * @param w the width of the newly constructed
         * <code>Rectangle2D</code>
	 * @param h the height of the newly constructed
         * <code>Rectangle2D</code>
	 * @since 1.2
	*/
	public Float(float x, float y, float w, float h) {
	    setRect(x, y, w, h);
	}

	/**
	 * Returns the X coordinate of this <code>Rectangle2D</code>
         * in double precision.
         * @return the X coordinate of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public double getX() {
	    return (double) x;
	}

	/**
	 * Returns the Y coordinate of this <code>Rectangle2D</code>
         * in double precision.
         * @return the Y coordinate of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public double getY() {
	    return (double) y;
	}

	/**
	 * Returns the width of this <code>Rectangle2D</code>
         * in double precision.
         * @return the width of this <code>Rectangle2D</code>.	 
         * @since 1.2
	 */
	public double getWidth() {
	    return (double) width;
	}

	/**
         * Returns the height of this <code>Rectangle2D</code>
         * in double precision.
         * @return the height of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public double getHeight() {
	    return (double) height;
	}

	/**
	 * Determines whether or not this <code>Rectangle2D</code> 
         * is empty.
         * @return <code>true</code> if this <code>Rectangle2D</code>
         * is empty; <code>false</code> otherwise.
	 * @since 1.2
	 */
	public boolean isEmpty() {
	    return (width <= 0.0f) || (height <= 0.0f);
	}

	/**
	 * Sets the location and size of this <code>Rectangle2D</code>
         * to the specified float values.
         * @param x,&nbsp;y the coordinates to which to set the 
         * location of the upper left corner of this
         * <code>Rectangle2D</code>
         * @param w the value to use to set the width of this
         * <code>Rectangle2D</code>
         * @param h the value to use to set the height of this
         * <code>Rectangle2D</code>
	 * @since 1.2
	 */
	public void setRect(float x, float y, float w, float h) {
	    this.x = x;
	    this.y = y;
	    this.width = w;
	    this.height = h;
	}

	/**
	 * Sets the location and size of this <code>Rectangle2D</code>
         * to the specified double values.
         * @param x,&nbsp;y the coordinates to which to set the
         * location of the upper left corner of this
         * <code>Rectangle2D</code>
         * @param w the value to use to set the width of this
         * <code>Rectangle2D</code>
         * @param h the value to use to set the height of this
         * <code>Rectangle2D</code>
	 * @since 1.2
	 */
	public void setRect(double x, double y, double w, double h) {
	    this.x = (float) x;
	    this.y = (float) y;
	    this.width = (float) w;
	    this.height = (float) h;
	}

	/**
	 * Sets this <code>Rectangle2D</code> to be the same as the
         * specified <code>Rectangle2D</code>.
         * @param r the specified <code>Rectangle2D</code>
	 * @since 1.2
	 */
	public void setRect(Rectangle2D r) {
	    this.x = (float) r.getX();
	    this.y = (float) r.getY();
	    this.width = (float) r.getWidth();
	    this.height = (float) r.getHeight();
	}

	/**
	 * Determines where the specified float coordinates lie with respect
	 * to this <code>Rectangle2D</code>.
	 * This method computes a binary OR of the appropriate mask values
	 * indicating, for each side of this <code>Rectangle2D</code>, 
         * whether or not the specified coordinates are on the same side
         * of the edge as the rest of this <code>Rectangle2D</code>.
         * @param x,&nbsp;y the specified coordinates
         * @return the logical OR of all appropriate out codes.
	 * @see Rectangle2D#OUT_LEFT
	 * @see Rectangle2D#OUT_TOP
	 * @see Rectangle2D#OUT_RIGHT
	 * @see Rectangle2D#OUT_BOTTOM
	 * @since 1.2
	 */
	public int outcode(double x, double y) {
	    /*
	     * Note on casts to double below.  If the arithmetic of
	     * x+w or y+h is done in float, then some bits may be
	     * lost if the binary exponents of x/y and w/h are not
	     * similar.  By converting to double before the addition
	     * we force the addition to be carried out in double to
	     * avoid rounding error in the comparison.
	     *
	     * See bug 4320890 for problems that this inaccuracy causes.
	     */
	    int out = 0;
	    if (this.width <= 0) {
		out |= OUT_LEFT | OUT_RIGHT;
	    } else if (x < this.x) {
		out |= OUT_LEFT;
	    } else if (x > this.x + (double) this.width) {
		out |= OUT_RIGHT;
	    }
	    if (this.height <= 0) {
		out |= OUT_TOP | OUT_BOTTOM;
	    } else if (y < this.y) {
		out |= OUT_TOP;
	    } else if (y > this.y + (double) this.height) {
		out |= OUT_BOTTOM;
	    }
	    return out;
	}

	/**
	 * Returns the high precision bounding box of this
         * <code>Rectangle2D</code>.
         * @return the bounding box of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public Rectangle2D getBounds2D() {
	    return new Float(x, y, width, height);
	}

	/**
	 * Returns a new <code>Rectangle2D</code> object 
         * representing the intersection of 
	 * this <code>Rectangle2D</code> with the specified
         * <code>Rectangle2D</code>.
	 * @param r the <code>Rectangle2D</code> that is
         * intersected with this <code>Rectangle2D</code>
	 * @return the largest <code>Rectangle2D</code> 
         * contained in both the specified 
         * <code>Rectangle2D</code> and in this 
         * <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public Rectangle2D createIntersection(Rectangle2D r) {
	    Rectangle2D dest;
	    if (r instanceof Float) {
		dest = new Rectangle2D.Float();
	    } else {
		dest = new Rectangle2D.Double();
	    }
	    Rectangle2D.intersect(this, r, dest);
	    return dest;
	}

	/**
	 * Returns a new <code>Rectangle2D</code> object 
         * representing the union of this <code>Rectangle2D</code>
         * with the specified <code>Rectangle2D</code>.
	 * @param r the <code>Rectangle2D</code> to be combined with
         * this <code>Rectangle2D</code>
	 * @return the smallest <code>Rectangle2D</code> containing 
         * both the specified <code>Rectangle2D</code> and this 
         * <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public Rectangle2D createUnion(Rectangle2D r) {
	    Rectangle2D dest;
	    if (r instanceof Float) {
		dest = new Rectangle2D.Float();
	    } else {
		dest = new Rectangle2D.Double();
	    }
	    Rectangle2D.union(this, r, dest);
	    return dest;
	}

	/**
	 * Returns the <code>String</code> representation of this
         * <code>Rectangle2D</code>.
         * @return a <code>String</code> representing this
         * <code>Rectangle2D</code>. 
	 * @since 1.2
	 */
	public String toString() {
	    return getClass().getName()
		+ "[x=" + x +
		",y=" + y +
		",w=" + width +
		",h=" + height + "]";
	}
    }

    /**
     * The <code>Double</code> class defines a rectangle specified in
     * double coordinates.
     * @since 1.2
     */
    public static class Double extends Rectangle2D {
	/**
	 * The x coordinate of this <code>Rectangle2D</code>.
	 * @since 1.2
	 */
	public double x;