org.eclipse.swt.graphics.ImageDataProvider Maven / Gradle / Ivy

/*******************************************************************************
 * Copyright (c) 2015 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.swt.graphics;

/**
 * Interface to provide a callback mechanism to get information about images
 * when the application is moved from a low DPI monitor to a high DPI monitor.
 * This provides API which will be called by SWT during the image rendering.
 *
 * This interface needs to be implemented by client code to provide the
 * image information on demand.
 *
 * @since 3.104
 */
public interface ImageDataProvider {


	/**
	 * Returns the image data for the given zoom level.
	 * 
	 * If no image is available for a particular zoom level, this method should
	 * return null. For zoom == 100, returning
	 * null in not allowed, and SWT will throw an exception.
	 *
	 * @param zoom
	 *            The zoom level in % of the standard resolution (which is 1
	 *            physical monitor pixel == 1 SWT logical pixel). Typically 100,
	 *            150, or 200.
	 * @return the image data, or null if zoom != 100
	 *         and no image is available for the given zoom level.
	 * @since 3.104
	 */
	public ImageData getImageData (int zoom);

}