    001/* ===================================================
    002 * JFreeSVG : an SVG library for the Java(tm) platform
    003 * ===================================================
    004 *
    005 * (C)opyright 2013, 2014, by Object Refinery Limited.  All rights reserved.
    006 *
    007 * Project Info:  http://www.jfree.org/jfreesvg/index.html
    008 *
    009 * This program is free software: you can redistribute it and/or modify
    010 * it under the terms of the GNU General Public License as published by
    011 * the Free Software Foundation, either version 3 of the License, or
    012 * (at your option) any later version.
    013 *
    014 * This program is distributed in the hope that it will be useful,
    015 * but WITHOUT ANY WARRANTY; without even the implied warranty of
    016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    017 * GNU General Public License for more details.
    018 *
    019 * You should have received a copy of the GNU General Public License
    020 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    021 *
    022 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    023 * Other names may be trademarks of their respective owners.]
    024 *
    025 * If you do not wish to be bound by the terms of the GPL, an alternative
    026 * commercial license can be purchased.  For details, please see visit the
    027 * JFreeSVG home page:
    028 *
    029 * http://www.jfree.org/jfreesvg
    030 *
    031 */
    032
    033package org.jfree.graphics2d;
    034
    035import java.awt.Polygon;
    036import java.awt.Shape;
    037import java.awt.geom.Arc2D;
    038import java.awt.geom.Ellipse2D;
    039import java.awt.geom.GeneralPath;
    040import java.awt.geom.Line2D;
    041import java.awt.geom.Path2D;
    042import java.awt.geom.Rectangle2D;
    043import java.awt.geom.RoundRectangle2D;
    044import java.awt.image.BufferedImage;
    045import java.awt.image.ColorModel;
    046import java.awt.image.RenderedImage;
    047import java.awt.image.WritableRaster;
    048import java.util.Hashtable;
    049
    050/**
    051 * A collection of static utility methods for shapes and images.
    052 */
    053public final class GraphicsUtils {
    054
    055    private GraphicsUtils() {
    056        // no need to instantiate this
    057    }
    058
    059    /**
    060     * Returns a shape that is (more or less) equivalent to the supplied shape.
    061     * For some known shape implementations (<code>Line2D</code>,
    062     * <code>Rectangle2D</code>, <code>RoundRectangle2D</code>,
    063     * <code>Arc2D</code>, <code>Ellipse2D</code>, and <code>Polygon</code>)
    064     * the copy will be an instance of that class.  For other shapes, a
    065     * <code>Path2D</code> containing the outline of the shape is returned.
    066     *
    067     * @param shape  the shape (<code>null</code> not permitted).
    068     *
    069     * @return A copy of the shape or shape outline (never <code>null</code>).
    070     */
    071    public static Shape copyOf(Shape shape) {
    072       Args.nullNotPermitted(shape, "shape");
    073       if (shape instanceof Line2D) {
    074           Line2D l = (Line2D) shape;
    075           return new Line2D.Double(l.getX1(), l.getY1(), l.getX2(), l.getY2());
    076       }
    077       if (shape instanceof Rectangle2D) {
    078           Rectangle2D r = (Rectangle2D) shape;
    079           return new Rectangle2D.Double(r.getX(), r.getY(), r.getWidth(),
    080                   r.getHeight());
    081       }
    082       if (shape instanceof RoundRectangle2D) {
    083           RoundRectangle2D rr = (RoundRectangle2D) shape;
    084           return new RoundRectangle2D.Double(rr.getX(), rr.getY(),
    085                   rr.getWidth(), rr.getHeight(), rr.getArcWidth(),
    086                   rr.getArcHeight());
    087       }
    088       if (shape instanceof Arc2D) {
    089           Arc2D arc = (Arc2D) shape;
    090           return new Arc2D.Double(arc.getX(), arc.getY(), arc.getWidth(),
    091                   arc.getHeight(), arc.getAngleStart(), arc.getAngleExtent(),
    092                   arc.getArcType());
    093       }
    094       if (shape instanceof Ellipse2D) {
    095           Ellipse2D ell = (Ellipse2D) shape;
    096           return new Ellipse2D.Double(ell.getX(), ell.getY(), ell.getWidth(),
    097                   ell.getHeight());
    098       }
    099       if (shape instanceof Polygon) {
    100           Polygon p = (Polygon) shape;
    101           return new Polygon(p.xpoints, p.ypoints, p.npoints);
    102       }
    103       return new Path2D.Double(shape);
    104    }
    105
    106    /**
    107     * Creates a polygon from the specified <code>x</code> and
    108     * <code>y</code> coordinate arrays.
    109     *
    110     * @param xPoints  the x-points.
    111     * @param yPoints  the y-points.
    112     * @param nPoints  the number of points to use for the polyline.
    113     * @param close  closed?
    114     *
    115     * @return A polygon.
    116     */
    117    public static GeneralPath createPolygon(int[] xPoints, int[] yPoints,
    118            int nPoints, boolean close) {
    119        GeneralPath p = new GeneralPath();
    120        p.moveTo(xPoints[0], yPoints[0]);
    121        for (int i = 1; i < nPoints; i++) {
    122            p.lineTo(xPoints[i], yPoints[i]);
    123        }
    124        if (close) {
    125            p.closePath();
    126        }
    127        return p;
    128    }
    129
    130    /**
    131     * Converts a rendered image to a <code>BufferedImage</code>.  This utility
    132     * method has come from a forum post by Jim Moore at:
    133     * <p>
    134     * <a href="http://www.jguru.com/faq/view.jsp?EID=114602">
    135     * http://www.jguru.com/faq/view.jsp?EID=114602</a>
    136     *
    137     * @param img  the rendered image.
    138     *
    139     * @return A buffered image.
    140     */
    141    public static BufferedImage convertRenderedImage(RenderedImage img) {
    142        if (img instanceof BufferedImage) {
    143            return (BufferedImage) img;
    144        }
    145        ColorModel cm = img.getColorModel();
    146        int width = img.getWidth();
    147        int height = img.getHeight();
    148        WritableRaster raster = cm.createCompatibleWritableRaster(width, height);
    149        boolean isAlphaPremultiplied = cm.isAlphaPremultiplied();
    150        Hashtable properties = new Hashtable();
    151        String[] keys = img.getPropertyNames();
    152        if (keys != null) {
    153            for (int i = 0; i < keys.length; i++) {
    154                properties.put(keys[i], img.getProperty(keys[i]));
    155            }
    156        }
    157        BufferedImage result = new BufferedImage(cm, raster,
    158                isAlphaPremultiplied, properties);
    159        img.copyData(raster);
    160        return result;
    161    }
    162}