001/*
002 * This file is part of McIDAS-V
003 *
004 * Copyright 2007-2016
005 * Space Science and Engineering Center (SSEC)
006 * University of Wisconsin - Madison
007 * 1225 W. Dayton Street, Madison, WI 53706, USA
008 * https://www.ssec.wisc.edu/mcidas
009 * 
010 * All Rights Reserved
011 * 
012 * McIDAS-V is built on Unidata's IDV and SSEC's VisAD libraries, and
013 * some McIDAS-V source code is based on IDV and VisAD source code.  
014 * 
015 * McIDAS-V is free software; you can redistribute it and/or modify
016 * it under the terms of the GNU Lesser Public License as published by
017 * the Free Software Foundation; either version 3 of the License, or
018 * (at your option) any later version.
019 * 
020 * McIDAS-V is distributed in the hope that it will be useful,
021 * but WITHOUT ANY WARRANTY; without even the implied warranty of
022 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
023 * GNU Lesser Public License for more details.
024 * 
025 * You should have received a copy of the GNU Lesser Public License
026 * along with this program.  If not, see http://www.gnu.org/licenses.
027 */
028
029package edu.wisc.ssec.mcidasv.ui;
030
031import static java.awt.RenderingHints.KEY_ANTIALIASING;
032import static java.awt.RenderingHints.KEY_INTERPOLATION;
033import static java.awt.RenderingHints.KEY_RENDERING;
034import static java.awt.RenderingHints.VALUE_ANTIALIAS_ON;
035import static java.awt.RenderingHints.VALUE_INTERPOLATION_BICUBIC;
036import static java.awt.RenderingHints.VALUE_RENDER_QUALITY;
037import static java.awt.geom.AffineTransform.getScaleInstance;
038
039import java.awt.Color;
040import java.awt.Graphics;
041import java.awt.Graphics2D;
042import java.awt.Image;
043import java.awt.RenderingHints;
044import java.awt.image.BufferedImage;
045
046import javax.swing.JPanel;
047
048/**
049 * Extend JPanel to draw an optionally anti-aliased image filling the panel.
050 */
051public class JPanelImage extends JPanel {
052
053    /** Image to draw within the {@code JPanel}. May be {@code null}. */
054    private Image theImage;
055
056    /** Whether or not anti-aliasing is being used. */
057    private boolean antiAlias;
058
059    /**
060     * Create a {@code JPanelImage} without specifying an {@link Image}. Note
061     * that this sets {@link #antiAlias} to {@code true}.
062     */
063    public JPanelImage() {
064        antiAlias = true;
065    }
066
067    /**
068     * Create a {@code JPanelImage} that contains the specified {@link Image}.
069     * Note that this sets {@link #antiAlias} to {@code true}.
070     *
071     * @param panelImage {@code Image} to use within the created panel.
072     * {@code null} is allowed.
073     */
074    public JPanelImage(Image panelImage) {
075        antiAlias = true;
076        theImage = panelImage;
077    }
078
079    /**
080     * Determine whether or not this {@code JPanelImage} is using
081     * anti-aliasing.
082     *
083     * @return {@code true} if anti-aliasing is enabled, {@code false}
084     * otherwise. Default value is {@code true}.
085     */
086    public boolean getAntiAlias() {
087        return antiAlias;
088    }
089
090    /**
091     * Set whether or not this {@code JPanelImage} should use anti-aliasing.
092     *
093     * @param setAA {@code true} if anti-aliasing should be enabled,
094     * {@code false} otherwise.
095     */
096    public void setAntiAlias(boolean setAA) {
097        antiAlias = setAA;
098    }
099
100    /**
101     * Return the {@link Image} being used within this {@code JPanelImage}.
102     *
103     * @return {@code Image} being used, or {@code null} if the {@code Image}
104     * has not been provided.
105     */
106    public Image getImage() {
107        return theImage;
108    }
109
110    /**
111     * Set the {@link Image} to use within this {@code JPanelImage}.
112     *
113     * @param panelImage {@code Image} to use. {@code null} is permitted.
114     */
115    public void setImage(Image panelImage) {
116        theImage = panelImage;
117    }
118
119    /**
120     * Update the panel after a change. Note that this is the same as calling
121     * {@link #paint(java.awt.Graphics)}.
122     *
123     * @param g Specified graphics window. Should not be {@code null}.
124     */
125    @Override public void update(Graphics g) {
126        paint(g);
127    }
128
129    /**
130     * Paint the {@code JPanelImage}.
131     *
132     * @param g Specified graphics window. Should not be {@code null}.
133     */
134    @Override public void paint(Graphics g) {
135        int width = getWidth();
136        int height = getHeight();
137        if (antiAlias) {
138            BufferedImage newImage =
139                new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
140            double scaleX = theImage.getWidth(null) / (double)width;
141            double scaleY = theImage.getHeight(null) / (double)height;
142            double scaleXY = 1.0 / Math.max(scaleX, scaleY);
143            Graphics2D g2d = newImage.createGraphics();
144            g2d.setBackground(Color.black);
145            g2d.clearRect(0, 0, width, height);
146            RenderingHints hints = new RenderingHints(null);
147            hints.put(KEY_ANTIALIASING, VALUE_ANTIALIAS_ON);
148            hints.put(KEY_INTERPOLATION, VALUE_INTERPOLATION_BICUBIC);
149            hints.put(KEY_RENDERING, VALUE_RENDER_QUALITY);
150            g2d.setRenderingHints(hints);
151            g2d.drawImage(theImage, getScaleInstance(scaleXY, scaleXY), null);
152            g.drawImage(newImage, 0, 0, null);
153        } else {
154            g.drawImage(theImage, 0, 0, width, height, null);
155        }
156    }
157}