bundles/org.eclipse.draw2d/src/org/eclipse/draw2d/geometry/PrecisionPoint.java

/*******************************************************************************
 * Copyright (c) 2000, 2010 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.draw2d.geometry;

/**
 * @author danlee
 */
public class PrecisionPoint extends Point {

	private static final long serialVersionUID = 1L;

	/**
	 * Double value for X
	 * 
	 * @noreference
	 * @deprecated Use {@link #setPreciseX(double)} and {@link #preciseX()}
	 *             instead. This field will become private in future versions.
	 */
	public double preciseX;

	/**
	 * Double value for Y
	 * 
	 * @noreference
	 * @deprecated Use {@link #setPreciseY(double)} and {@link #preciseY()}
	 *             instead. This field will become private in future versions.
	 */
	public double preciseY;

	/**
	 * Constructor for PrecisionPoint.
	 */
	public PrecisionPoint() {
		super();
	}

	/**
	 * Constructor for PrecisionPoint.
	 * 
	 * @param x
	 *            X value
	 * @param y
	 *            Y value
	 */
	public PrecisionPoint(double x, double y) {
		setPreciseLocation(x, y);
	}

	/**
	 * Constructor for PrecisionPoint.
	 * 
	 * @param x
	 *            X value
	 * @param y
	 *            Y value
	 */
	public PrecisionPoint(int x, int y) {
		this((double) x, (double) y);
	}

	/**
	 * Constructor for PrecisionPoint.
	 * 
	 * @param p
	 *            Point from which the initial values are taken
	 */
	public PrecisionPoint(Point p) {
		this(p.preciseX(), p.preciseY());
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#equals(java.lang.Object)
	 */
	public boolean equals(Object o) {
		if (o instanceof PrecisionPoint) {
			PrecisionPoint p = (PrecisionPoint) o;
			return p.preciseX() == preciseX() && p.preciseY() == preciseY();
		}
		return super.equals(o);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#getCopy()
	 */
	public Point getCopy() {
		return getPreciseCopy();
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#getDifference(org.eclipse.draw2d.geometry.Point)
	 */
	public Dimension getDifference(Point p) {
		return new PrecisionDimension(this.preciseX() - p.preciseX(),
				this.preciseY() - p.preciseY());
	}

	/**
	 * Returns a precise copy of this.
	 * 
	 * @return a precise copy
	 * @since 3.7
	 */
	public PrecisionPoint getPreciseCopy() {
		return new PrecisionPoint(preciseX(), preciseY());
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#performScale(double)
	 */
	public void performScale(double factor) {
		setPreciseX(preciseX() * factor);
		setPreciseY(preciseY() * factor);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#performTranslate(int, int)
	 */
	public void performTranslate(int dx, int dy) {
		setPreciseX(preciseX() + dx);
		setPreciseY(preciseY() + dy);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#preciseX()
	 */
	public double preciseX() {
		updatePreciseXDouble();
		return preciseX;
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#preciseY()
	 */
	public double preciseY() {
		updatePreciseYDouble();
		return preciseY;
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#scale(double, double)
	 */
	public Point scale(double xFactor, double yFactor) {
		setPreciseX(preciseX() * xFactor);
		setPreciseY(preciseY() * yFactor);
		return this;
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#setLocation(int, int)
	 */
	public Point setLocation(int x, int y) {
		return setPreciseLocation(x, y);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#setLocation(Point)
	 */
	public Point setLocation(Point pt) {
		return setPreciseLocation(pt.preciseX(), pt.preciseY());
	}

	/**
	 * Sets the precise location of this PrecisionPoint to the given x and y
	 * values.
	 * 
	 * @param x
	 *            The new x value
	 * @param y
	 *            The new y value
	 * @return this for convenience
	 * @since 3.7
	 */
	public PrecisionPoint setPreciseLocation(double x, double y) {
		setPreciseX(x);
		setPreciseY(y);
		return this;
	}

	/**
	 * Sets the precise location of this PrecisionPoint to the x and y values of
	 * the given one.
	 * 
	 * @param p
	 *            The PrecisionPoint specifying the new x and y values.
	 * @return this for convenience
	 * @since 3.7
	 */
	public PrecisionPoint setPreciseLocation(PrecisionPoint p) {
		return setPreciseLocation(p.preciseX(), p.preciseY());
	}

	/**
	 * Sets the precise x value of this PrecisionPoint to the given value.
	 * 
	 * @param x
	 *            The new x value
	 * @return this for convenience
	 * @since 3.7
	 */
	public PrecisionPoint setPreciseX(double x) {
		preciseX = x;
		updateXInt();
		return this;
	}

	/**
	 * Sets the precise y value of this PrecisionPoint to the given value.
	 * 
	 * @param y
	 *            The new y value
	 * @return this for convenience
	 * @since 3.7
	 */
	public PrecisionPoint setPreciseY(double y) {
		preciseY = y;
		updateYInt();
		return this;
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#setX(int)
	 */
	public Point setX(int x) {
		return setPreciseX(x);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#setY(int)
	 */
	public Point setY(int y) {
		return setPreciseY(y);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#translate(org.eclipse.draw2d.geometry.Dimension)
	 */
	public Point translate(Dimension d) {
		return translatePrecise(d.preciseWidth(), d.preciseHeight());
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#translate(int, int)
	 */
	public Point translate(int dx, int dy) {
		return translatePrecise(dx, dy);
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#translate(org.eclipse.draw2d.geometry.Point)
	 */
	public Point translate(Point p) {
		return translatePrecise(p.preciseX(), p.preciseY());
	}

	/**
	 * Shifts this Point by the values supplied along each axes, and returns
	 * this for convenience.
	 * 
	 * @param dx
	 *            Amount by which point is shifted along X axis.
	 * @param dy
	 *            Amount by which point is shifted along Y axis.
	 * @return <code>this</code> for convenience
	 * @since 3.7
	 */
	private PrecisionPoint translatePrecise(double dx, double dy) {
		setPreciseX(preciseX() + dx);
		setPreciseY(preciseY() + dy);
		return this;
	}

	/**
	 * @see org.eclipse.draw2d.geometry.Point#transpose()
	 */
	public Point transpose() {
		double temp = preciseX();
		setPreciseX(preciseY());
		setPreciseY(temp);
		return this;
	}

	/**
	 * Updates the integer fields using the precise versions.
	 * 
	 * @deprecated This method should not be accessed by clients any more (it
	 *             will be made private in future releases). The update of
	 *             integer and precision fields is performed automatically if
	 *             {@link #preciseX} and {@link #preciseY} field values are not
	 *             manipulated directly, but only via respective methods offered
	 *             by this class.
	 */
	public final void updateInts() {
		updateXInt();
		updateYInt();
	}

	/**
	 * Updates the x integer field using the value of preciseX.
	 */
	private final void updateXInt() {
		x = PrecisionGeometry.doubleToInteger(preciseX);
	}

	/**
	 * Updates the y integer field using the value of preciseY.
	 */
	private final void updateYInt() {
		y = PrecisionGeometry.doubleToInteger(preciseY);
	}

	/**
	 * Updates the preciseX double field using the value of x.
	 */
	private final void updatePreciseXDouble() {
		if (x != PrecisionGeometry.doubleToInteger(preciseX)) {
			preciseX = x;
		}
	}

	/**
	 * Updates the preciseY double field using the value of y.
	 */
	private final void updatePreciseYDouble() {
		if (y != PrecisionGeometry.doubleToInteger(preciseY)) {
			preciseY = y;
		}
	}

}