001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2021, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * --------------------
028 * ShadowGenerator.java
029 * --------------------
030 * (C) Copyright 2009-2021, by Object Refinery Limited and Contributors.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 */
036
037package org.jfree.chart.util;
038
039import java.awt.image.BufferedImage;
040
041/**
042 * An interface that defines the API for a shadow generator.  Some plot
043 * classes use this to create drop shadows.
044 */
045public interface ShadowGenerator {
046
047    /**
048     * Creates and returns an image containing the drop shadow for the
049     * specified source image.
050     *
051     * @param source  the source image.
052     *
053     * @return A new image containing the shadow.
054     */
055    public BufferedImage createDropShadow(BufferedImage source);
056
057    /**
058     * Calculates the x-offset for drawing the shadow image relative to the
059     * source.
060     *
061     * @return The x-offset.
062     */
063    public int calculateOffsetX();
064
065    /**
066     * Calculates the y-offset for drawing the shadow image relative to the
067     * source.
068     *
069     * @return The y-offset.
070     */
071    public int calculateOffsetY();
072
073}