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/******************************************************************************* * Copyright (c) 2006, 2008 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.egit.ui.internal; import java.util.Arrays; import org.eclipse.egit.ui.UIUtils; import org.eclipse.jface.resource.CompositeImageDescriptor; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.jface.viewers.DecorationOverlayIcon; import org.eclipse.jface.viewers.IDecoration; import org.eclipse.swt.graphics.ImageData; import org.eclipse.swt.graphics.Point; /** * A <code>DecorationOverlayIcon</code> is an image descriptor that can be used * to overlay decoration images on to the 4 corner quadrants of a base image * descriptor. The four quadrants are {@link IDecoration#TOP_LEFT}, * {@link IDecoration#TOP_RIGHT}, {@link IDecoration#BOTTOM_LEFT} and * {@link IDecoration#BOTTOM_RIGHT}. Additionally, the overlay can be used to * provide an underlay corresponding to {@link IDecoration#UNDERLAY}. * * This class is modeled after {@link DecorationOverlayIcon} but supports using * a base image descriptor instead of a base image. */ public class DecorationOverlayDescriptor extends CompositeImageDescriptor { // the base image private ImageDescriptor base; // the overlay images private ImageDescriptor[] overlays; // the size private Point size; /** * Create the decoration overlay for the base image descriptor using the * array of provided overlays. The indices of the array correspond to the * values of the 5 overlay constants defined on {@link IDecoration} ( * {@link IDecoration#TOP_LEFT}, {@link IDecoration#TOP_RIGHT}, * {@link IDecoration#BOTTOM_LEFT}, {@link IDecoration#BOTTOM_RIGHT} and * {@link IDecoration#UNDERLAY}). * * @param baseImage * the base image * @param overlaysArray * the overlay images * @param sizeValue * the size of the resulting image */ public DecorationOverlayDescriptor(ImageDescriptor baseImage, ImageDescriptor[] overlaysArray, Point sizeValue) { this.base = baseImage; this.overlays = overlaysArray; this.size = sizeValue; } /** * Create the decoration overlay for the base image descriptor using the * array of provided overlays. The indices of the array correspond to the * values of the 5 overlay constants defined on {@link IDecoration} ( * {@link IDecoration#TOP_LEFT}, {@link IDecoration#TOP_RIGHT}, * {@link IDecoration#BOTTOM_LEFT}, {@link IDecoration#BOTTOM_RIGHT} and * {@link IDecoration#UNDERLAY}). * * @param baseImage * the base image * @param overlaysArray * the overlay images */ public DecorationOverlayDescriptor(ImageDescriptor baseImage, ImageDescriptor[] overlaysArray) { this(baseImage, overlaysArray, UIUtils.getSize(baseImage)); } /** * Create a decoration overlay icon that will place the given overlay icon * in the given quadrant of the base image descriptor. * * @param baseImage * the base image * @param overlayImage * the overlay image * @param quadrant * the quadrant (one of {@link IDecoration} ( * {@link IDecoration#TOP_LEFT}, {@link IDecoration#TOP_RIGHT}, * {@link IDecoration#BOTTOM_LEFT}, * {@link IDecoration#BOTTOM_RIGHT} or * {@link IDecoration#UNDERLAY}) */ public DecorationOverlayDescriptor(ImageDescriptor baseImage, ImageDescriptor overlayImage, int quadrant) { this(baseImage, createArrayFrom(overlayImage, quadrant)); } /** * Convert the given image and quadrant into the proper input array. * * @param overlayImage * the overlay image * @param quadrant * the quadrant * @return an array with the given image in the proper quadrant */ private static ImageDescriptor[] createArrayFrom(ImageDescriptor overlayImage, int quadrant) { ImageDescriptor[] descs = new ImageDescriptor[] { null, null, null, null, null }; descs[quadrant] = overlayImage; return descs; } /** * Draw the overlays for the receiver. * * @param overlaysArray */ private void drawOverlays(ImageDescriptor[] overlaysArray) { for (int i = 0; i < overlays.length; i++) { ImageDescriptor overlay = overlaysArray[i]; if (overlay == null) continue; ImageData overlayData = overlay.getImageData(); // Use the missing descriptor if it is not there. if (overlayData == null) overlayData = ImageDescriptor.getMissingImageDescriptor().getImageData(); switch (i) { case IDecoration.TOP_LEFT: drawImage(overlayData, 0, 0); break; case IDecoration.TOP_RIGHT: drawImage(overlayData, size.x - overlayData.width, 0); break; case IDecoration.BOTTOM_LEFT: drawImage(overlayData, 0, size.y - overlayData.height); break; case IDecoration.BOTTOM_RIGHT: drawImage(overlayData, size.x - overlayData.width, size.y - overlayData.height); break; } } } public boolean equals(Object o) { if (!(o instanceof DecorationOverlayDescriptor)) return false; DecorationOverlayDescriptor other = (DecorationOverlayDescriptor) o; return base.equals(other.base) && Arrays.equals(overlays, other.overlays); } public int hashCode() { int code = base.hashCode(); for (int i = 0; i < overlays.length; i++) if (overlays[i] != null) code ^= overlays[i].hashCode(); return code; } protected void drawCompositeImage(int width, int height) { if (overlays.length > IDecoration.UNDERLAY) { ImageDescriptor underlay = overlays[IDecoration.UNDERLAY]; if (underlay != null) drawImage(underlay.getImageData(), 0, 0); } if (overlays.length > IDecoration.REPLACE && overlays[IDecoration.REPLACE] != null) drawImage(overlays[IDecoration.REPLACE].getImageData(), 0, 0); else drawImage(getBaseImageData(), 0, 0); drawOverlays(overlays); } private ImageData getBaseImageData() { final ImageData data = base.getImageData(); return data != null ? data : DEFAULT_IMAGE_DATA; } protected Point getSize() { return size; } protected int getTransparentPixel() { return getBaseImageData().transparentPixel; } }