package rtree;/** * A HyperCube in the n-dimensional space. It is represented by two points of n dimensions each. * <p> * Implements basic calculation functions, like <B>getArea()</B> and <B>getUnionMbb()</B>. * <p> * Created: Tue May 18 14:33:37 1999 * <p> * @author Hadjieleftheriou Marios * @version 1.1 */public class HyperCube implements Cloneable {    private Point p1;    private Point p2;    public HyperCube(Point p1, Point p2) {	if (p1 == null || p2 == null) throw new	    IllegalArgumentException("Points cannot be null.");	if (p1.getDimension() != p2.getDimension()) throw new	    IllegalArgumentException("Points must be of the same dimension.");	for (int i = 0; i < p1.getDimension(); i++) {	    if (p1.getFloatCoordinate(i) > p2.getFloatCoordinate(i)) throw new		IllegalArgumentException("Give lower left corner first and upper right corner afterwards.");	}	this.p1 = (Point) p1.clone();	this.p2 = (Point) p2.clone();    }    public int getDimension() {	return p1.getDimension();    }    public Point getP1() {	return (Point) p1.clone();    }    public Point getP2() {	return (Point) p2.clone();    }    public boolean equals(HyperCube h) {	if (p1.equals(h.getP1()) && p2.equals(h.getP2())) {	    return true;	} else {	    return false;	}    }    /**     * Tests to see whether <B>h</B> has any common points with this HyperCube. If <B>h</B> is inside this     * object (or vice versa), it returns true.     *     * @return True if <B>h</B> and this HyperCube intersect, false otherwise.     */    public boolean intersection(HyperCube h) {	if (h == null) throw new	    IllegalArgumentException("HyperCube cannot be null.");	if (h.getDimension() != getDimension()) throw new	    IllegalArgumentException("HyperCube dimension is different from current dimension.");	boolean intersect = true;	for (int i = 0; i < getDimension(); i++) {	    if (p1.getFloatCoordinate(i) > h.p2.getFloatCoordinate(i) ||		p2.getFloatCoordinate(i) < h.p1.getFloatCoordinate(i)) {		intersect = false;		break;	    }	}	return intersect;    }    /**     * Tests to see whether <B>h</B> is inside this HyperCube. If <B>h</B> is exactly the same shape     * as this object, it is considered to be inside.     *     * @return True if <B>h</B> is inside, false otherwise.     */    public boolean enclosure(HyperCube h) {	if (h == null) throw new	    IllegalArgumentException("HyperCube cannot be null.");	if (h.getDimension() != getDimension()) throw new	    IllegalArgumentException("HyperCube dimension is different from current dimension.");	boolean inside = true;	for (int i = 0; i < getDimension(); i++) {	    if (p1.getFloatCoordinate(i) > h.p1.getFloatCoordinate(i) ||		p2.getFloatCoordinate(i) < h.p2.getFloatCoordinate(i)) {		inside = false;		break;	    }	}	return inside;    }    /**     * Tests to see whether <B>p</B> is inside this HyperCube. If <B>p</B> lies on the boundary     * of the HyperCube, it is considered to be inside the object.     *     * @return True if <B>p</B> is inside, false otherwise.     */    public boolean enclosure(Point p) {	if (p == null) throw new	    IllegalArgumentException("Point cannot be null.");	if (p.getDimension() != getDimension()) throw new	    IllegalArgumentException("Point dimension is different from HyperCube dimension.");	return enclosure(new HyperCube(p, p));    }    /**     * Returns the area of the intersecting region between this HyperCube and the argument.     *      * Below, all possible situations are depicted.     *     *     -------   -------      ---------   ---------      ------         ------     *    |2      | |2      |    |2        | |1        |    |2     |       |1     |     *  --|--     | |     --|--  | ------  | | ------  |  --|------|--   --|------|--     * |1 |  |    | |    |1 |  | ||1     | | ||2     | | |1 |      |  | |2 |      |  |     *  --|--     | |     --|--  | ------  | | ------  |  --|------|--   --|------|--     *     -------   -------      ---------   ---------      ------         ------     *     * @param h Given HyperCube.     * @return Area of intersecting region.     */    public float intersectingArea(HyperCube h) {	if (!intersection(h)) {	    return 0;	} else {	    float ret = 1;	    for (int i = 0; i < getDimension(); i++) {		float l1 = p1.getFloatCoordinate(i);		float h1 = p2.getFloatCoordinate(i);		float l2 = h.p1.getFloatCoordinate(i);		float h2 = h.p2.getFloatCoordinate(i);		if (l1 <= l2 && h1 <= h2) {		    // cube1 left of cube2.		    ret *= (h1 - l1) - (l2 - l1);		} else if (l2 <= l1 && h2 <= h1) {		    // cube1 right of cube2.		    ret *= (h2 - l2) - (l1 - l2);		} else if (l2 <= l1 && h1 <= h2) {		    // cube1 inside cube2.		    ret *= h1 - l1;		} else if (l1 <= l2 && h2 <= h1) {		    // cube1 contains cube2.		    ret *= h2 - l2;		} else if (l1 <= l2 && h2 <= h1) {		    // cube1 crosses cube2.		    ret *= h2 - l2;		} else if (l2 <= l1 && h1 <= h2) {		    // cube1 crossed by cube2.		    ret *= h1 - l1;		}	    }	    if (ret <= 0) throw new		ArithmeticException("Intersecting area cannot be negative!");	    return ret;	}    }    /**      * Static impementation. Takes an array of HyperCubes and calculates the mbb of their     * union.     *     * @param  a The array of HyperCubes.     * @return The mbb of their union.     */    public static HyperCube getUnionMbb(HyperCube[] a) {	if (a == null || a.length == 0) throw new	    IllegalArgumentException("HyperCube array is empty.");	HyperCube h = (HyperCube) a[0].clone();	for (int i = 1; i < a.length; i++) {	    h = h.getUnionMbb(a[i]);	}	return h;    }    /**     * Return a new HyperCube representing the mbb of the union of this HyperCube and <B>h</B>     *     * @param  h The HyperCube that we want to union with this HyperCube.     * @return  A HyperCube representing the mbb of their union.     */    public HyperCube getUnionMbb(HyperCube h) {	if (h == null) throw new	    IllegalArgumentException("HyperCube cannot be null.");	if (h.getDimension() != getDimension()) throw new	    IllegalArgumentException("HyperCubes must be of the same dimension.");	float[] min = new float[getDimension()];	float[] max = new float[getDimension()];	for (int i = 0; i < getDimension(); i++) {	    min[i] = Math.min(p1.getFloatCoordinate(i), h.p1.getFloatCoordinate(i));	    max[i] = Math.max(p2.getFloatCoordinate(i), h.p2.getFloatCoordinate(i));	}	return new HyperCube(new Point(min), new Point(max));    }    /**      * Returns the area of this HyperCube.      *     * @return The area as a float.     */    public float getArea() {	float area = 1;	for (int i = 0; i < getDimension(); i++) {	    area *= p2.getFloatCoordinate(i) - p1.getFloatCoordinate(i);	}	return area;    }    /* The MINDIST criterion as described by Roussopoulos.       FIXME: better description here...     */    public float getMinDist(Point p) {	if (p == null) throw new	    IllegalArgumentException("Point cannot be null.");	if (p.getDimension() != getDimension()) throw new	    IllegalArgumentException("Point dimension is different from HyperCube dimension.");	float ret = 0;	for (int i = 0; i < getDimension(); i++) {	    float q = p.getFloatCoordinate(i);	    float s = p1.getFloatCoordinate(i);	    float t = p2.getFloatCoordinate(i);	    float r;	    if (q < s) r = s;	    else if (q > t) r = t;	    else r = q;	    ret += Math.pow(Math.abs(q - r), 2);	}	return ret;    }    public Object clone() {	return new HyperCube((Point) p1.clone(), (Point) p2.clone());    }    public String toString() {	return "P1" + p1.toString() + ":P2" + p2.toString();    }} // HyperCube