/******************************************************************************* * Copyright (c) 2000, 2004 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Common Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/cpl-v10.html *  * Contributors: *     IBM Corporation - initial API and implementation *******************************************************************************/package org.eclipse.swt.graphics;import org.eclipse.swt.internal.win32.*;import org.eclipse.swt.*;/** * Instances of this class represent areas of an x-y coordinate * system that are aggregates of the areas covered by a number * of rectangles. * <p> * Application code must explicitly invoke the <code>Region.dispose()</code>  * method to release the operating system resources managed by each instance * when those instances are no longer required. * </p> */public final class Region {		/**	 * the OS resource for the region	 * (Warning: This field is platform dependent)	 */	public int handle;		/**	 * the device where this region was created	 */	Device device;/** * Constructs a new empty region. *  * @exception SWTError <ul> *    <li>ERROR_NO_HANDLES if a handle could not be obtained for region creation</li> * </ul> */public Region () {	this(null);}/** * Constructs a new empty region. * <p> * You must dispose the region when it is no longer required.  * </p> * * @param device the device on which to allocate the region ** @exception SWTError <ul> *    <li>ERROR_NO_HANDLES if a handle could not be obtained for region creation</li> * </ul> * @exception IllegalArgumentException <ul> *    <li>ERROR_NULL_ARGUMENT - if device is null and there is no current device</li> * </ul> * * @see #dispose *  * @since 3.0 */public Region (Device device) {	if (device == null) device = Device.getDevice();	if (device == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);	this.device = device;	handle = OS.CreateRectRgn (0, 0, 0, 0);	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);	if (device.tracking) device.new_Object(this);}/** * Constructs a new region given a handle to the operating * system resources that it should represent. *  * @param handle the handle for the result */Region(Device device, int handle) {	this.device = device;	this.handle = handle;}/** * Adds the given polygon to the collection of rectangles * the receiver maintains to describe its area. * * @param pointArray points that describe the polygon to merge with the receiver * * @exception IllegalArgumentException <ul> *    <li>ERROR_NULL_ARGUMENT - if the argument is null</li> * </ul> * @exception SWTException <ul> *    <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> * </ul> * * @since 3.0* */public void add (int[] pointArray) {	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);	if (pointArray == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);	if (OS.IsWinCE) SWT.error(SWT.ERROR_NOT_IMPLEMENTED);	int polyRgn = OS.CreatePolygonRgn(pointArray, pointArray.length / 2, OS.ALTERNATE);	OS.CombineRgn (handle, handle, polyRgn, OS.RGN_OR);	OS.DeleteObject (polyRgn);}/** * Adds the given rectangle to the collection of rectangles * the receiver maintains to describe its area. * * @param rect the rectangle to merge with the receiver * * @exception IllegalArgumentException <ul> *    <li>ERROR_NULL_ARGUMENT - if the argument is null</li> *    <li>ERROR_INVALID_ARGUMENT - if the rectangle's width or height is negative</li> * </ul> * @exception SWTException <ul> *    <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> * </ul> */public void add (Rectangle rect) {	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);	if (rect == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);	if (rect.width < 0 || rect.height < 0) SWT.error(SWT.ERROR_INVALID_ARGUMENT);		int rectRgn = OS.CreateRectRgn (rect.x, rect.y, rect.x + rect.width, rect.y + rect.height);	OS.CombineRgn (handle, handle, rectRgn, OS.RGN_OR);	OS.DeleteObject (rectRgn);}/** * Adds all of the rectangles which make up the area covered * by the argument to the collection of rectangles the receiver * maintains to describe its area. * * @param region the region to merge * * @exception IllegalArgumentException <ul> *    <li>ERROR_NULL_ARGUMENT - if the argument is null</li> *    <li>ERROR_INVALID_ARGUMENT - if the argument has been disposed</li> * </ul> * @exception SWTException <ul> *    <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> * </ul> */public void add (Region region) {	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);	if (region == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);	if (region.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);	OS.CombineRgn (handle, handle, region.handle, OS.RGN_OR);}/** * Returns <code>true</code> if the point specified by the * arguments is inside the area specified by the receiver, * and <code>false</code> otherwise. * * @param x the x coordinate of the point to test for containment * @param y the y coordinate of the point to test for containment * @return <code>true</code> if the region contains the point and <code>false</code> otherwise * * @exception SWTException <ul> *    <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> * </ul> */public boolean contains (int x, int y) {	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);	return OS.PtInRegion (handle, x, y);}/** * Returns <code>true</code> if the given point is inside the * area specified by the receiver, and <code>false</code> * otherwise. * * @param pt the point to test for containment * @return <code>true</code> if the region contains the point and <code>false</code> otherwise * * @exception IllegalArgumentException <ul> *    <li>ERROR_NULL_ARGUMENT - if the argument is null</li> * </ul> * @exception SWTException <ul> *    <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> * </ul> */public boolean contains (Point pt) {	if (pt == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);	return contains(pt.x, pt.y);}/** * Disposes of the operating system resources associated with * the region. Applications must dispose of all regions which * they allocate. */public void dispose () {	if (handle == 0) return;	if (device.isDisposed()) return;	OS.DeleteObject(handle);	handle = 0;	if (device.tracking) device.dispose_Object(this);	device = null;}/** * Compares the argument to the receiver, and returns true * if they represent the <em>same</em> object using a class * specific comparison. * * @param object the object to compare with this object * @return <code>true</code> if the object is the same as this object and <code>false</code> otherwise * * @see #hashCode */public boolean equals (Object object) {	if (this == object) return true;	if (!(object instanceof Region)) return false;	Region rgn = (Region)object;	return handle == rgn.handle;}/** * Returns a rectangle which represents the rectangular * union of the collection of rectangles the receiver * maintains to describe its area. * * @return a bounding rectangle for the region * * @exception SWTException <ul> *    <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> * </ul> * * @see Rectangle#union */public Rectangle getBounds() {	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);	RECT rect = new RECT();	OS.GetRgnBox(handle, rect);	return new Rectangle(rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top);}