482 lines · 21.9 KB · Java
RawDownload
/* * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package sun.java2d.pipe; import java.awt.Shape;import java.awt.BasicStroke;import java.awt.geom.PathIterator;import java.awt.geom.AffineTransform; import java.security.PrivilegedAction;import java.security.AccessController;import java.util.ServiceLoader;import sun.security.action.GetPropertyAction; import sun.awt.geom.PathConsumer2D; /** * This class abstracts a number of features for which the Java 2D * implementation relies on proprietary licensed software libraries. * Access to those features is now achieved by retrieving the singleton * instance of this class and calling the appropriate methods on it. * The 3 primary features abstracted here include: * <dl> * <dt>Shape createStrokedShape(Shape, [BasicStroke attributes]); * <dd>This method implements the functionality of the method of the * same name on the {@link BasicStroke} class. * <dt>void strokeTo(Shape, [rendering parameters], PathConsumer2D); * <dd>This method performs widening of the source path on the fly * and sends the results to the given {@link PathConsumer2D} object. * This procedure avoids having to create an intermediate Shape * object to hold the results of the {@code createStrokedShape} method. * The main user of this method is the Java 2D non-antialiasing renderer. * <dt>AATileGenerator getAATileGenerator(Shape, [rendering parameters]); * <dd>This method returns an object which can iterate over the * specified bounding box and produce tiles of coverage values for * antialiased rendering.  The details of the operation of the * {@link AATileGenerator} object are explained in its class comments. * </dl> * Additionally, the following informational method supplies important * data about the implementation. * <dl> * <dt>float getMinimumAAPenSize() * <dd>This method provides information on how small the BasicStroke * line width can get before dropouts occur.  Rendering with a BasicStroke * is defined to never allow the line to have breaks, gaps, or dropouts * even if the width is set to 0.0f, so this information allows the * {@link SunGraphics2D} class to detect the "thin line" case and set * the rendering attributes accordingly. * </dl> * At startup the runtime will load a single instance of this class. * It searches the classpath for a registered provider of this API * and returns either the last one it finds, or the instance whose * class name matches the value supplied in the System property * {@code sun.java2d.renderer}. * Additionally, a runtime System property flag can be set to trace * all calls to methods on the {@code RenderingEngine} in use by * setting the sun.java2d.renderer.trace property to any non-null value. * <p> * Parts of the system that need to use any of the above features should * call {@code RenderingEngine.getInstance()} to obtain the properly * registered (and possibly trace-enabled) version of the RenderingEngine. */public abstract class RenderingEngine {    private static RenderingEngine reImpl;     /**     * Returns an instance of {@code RenderingEngine} as determined     * by the installation environment and runtime flags.     * <p>     * A specific instance of the {@code RenderingEngine} can be     * chosen by specifying the runtime flag:     * <pre>     *     java -Dsun.java2d.renderer=&lt;classname&gt;     * </pre>     *     * If no specific {@code RenderingEngine} is specified on the command     * or Ductus renderer is specified, it will attempt loading the     * sun.dc.DuctusRenderingEngine class using Class.forName as a fastpath;     * if not found, use the ServiceLoader.     * If no specific {@code RenderingEngine} is specified on the command     * line then the last one returned by enumerating all subclasses of     * {@code RenderingEngine} known to the ServiceLoader is used.     * <p>     * Runtime tracing of the actions of the {@code RenderingEngine}     * can be enabled by specifying the runtime flag:     * <pre>     *     java -Dsun.java2d.renderer.trace=&lt;any string&gt;     * </pre>     * @return an instance of {@code RenderingEngine}     * @since 1.7     */    public static synchronized RenderingEngine getInstance() {        if (reImpl != null) {            return reImpl;        }         reImpl = (RenderingEngine)            AccessController.doPrivileged(new PrivilegedAction() {                public Object run() {                    final String ductusREClass = "sun.dc.DuctusRenderingEngine";                    String reClass =                        System.getProperty("sun.java2d.renderer", ductusREClass);                    if (reClass.equals(ductusREClass)) {                        try {                            Class cls = Class.forName(ductusREClass);                            return cls.newInstance();                        } catch (ClassNotFoundException x) {                            // not found                        } catch (IllegalAccessException x) {                            // should not reach here                        } catch (InstantiationException x) {                            // should not reach here                        }                    }                     ServiceLoader<RenderingEngine> reLoader =                        ServiceLoader.loadInstalled(RenderingEngine.class);                     RenderingEngine service = null;                     for (RenderingEngine re : reLoader) {                        service = re;                        if (re.getClass().getName().equals(reClass)) {                            break;                        }                    }                    return service;                }            });         if (reImpl == null) {            throw new InternalError("No RenderingEngine module found");        }         GetPropertyAction gpa =            new GetPropertyAction("sun.java2d.renderer.trace");        String reTrace = (String) AccessController.doPrivileged(gpa);        if (reTrace != null) {            reImpl = new Tracer(reImpl);        }         return reImpl;    }     /**     * Create a widened path as specified by the parameters.     * <p>     * The specified {@code src} {@link Shape} is widened according     * to the specified attribute parameters as per the     * {@link BasicStroke} specification.     *     * @param src the source path to be widened     * @param width the width of the widened path as per {@code BasicStroke}     * @param caps the end cap decorations as per {@code BasicStroke}     * @param join the segment join decorations as per {@code BasicStroke}     * @param miterlimit the miter limit as per {@code BasicStroke}     * @param dashes the dash length array as per {@code BasicStroke}     * @param dashphase the initial dash phase as per {@code BasicStroke}     * @return the widened path stored in a new {@code Shape} object     * @since 1.7     */    public abstract Shape createStrokedShape(Shape src,                                             float width,                                             int caps,                                             int join,                                             float miterlimit,                                             float dashes[],                                             float dashphase);     /**     * Sends the geometry for a widened path as specified by the parameters     * to the specified consumer.     * <p>     * The specified {@code src} {@link Shape} is widened according     * to the parameters specified by the {@link BasicStroke} object.     * Adjustments are made to the path as appropriate for the     * {@link VALUE_STROKE_NORMALIZE} hint if the {@code normalize}     * boolean parameter is true.     * Adjustments are made to the path as appropriate for the     * {@link VALUE_ANTIALIAS_ON} hint if the {@code antialias}     * boolean parameter is true.     * <p>     * The geometry of the widened path is forwarded to the indicated     * {@link PathConsumer2D} object as it is calculated.     *     * @param src the source path to be widened     * @param bs the {@code BasicSroke} object specifying the     *           decorations to be applied to the widened path     * @param normalize indicates whether stroke normalization should     *                  be applied     * @param antialias indicates whether or not adjustments appropriate     *                  to antialiased rendering should be applied     * @param consumer the {@code PathConsumer2D} instance to forward     *                 the widened geometry to     * @since 1.7     */    public abstract void strokeTo(Shape src,                                  AffineTransform at,                                  BasicStroke bs,                                  boolean thin,                                  boolean normalize,                                  boolean antialias,                                  PathConsumer2D consumer);     /**     * Construct an antialiased tile generator for the given shape with     * the given rendering attributes and store the bounds of the tile     * iteration in the bbox parameter.     * The {@code at} parameter specifies a transform that should affect     * both the shape and the {@code BasicStroke} attributes.     * The {@code clip} parameter specifies the current clip in effect     * in device coordinates and can be used to prune the data for the     * operation, but the renderer is not required to perform any     * clipping.     * If the {@code BasicStroke} parameter is null then the shape     * should be filled as is, otherwise the attributes of the     * {@code BasicStroke} should be used to specify a draw operation.     * The {@code thin} parameter indicates whether or not the     * transformed {@code BasicStroke} represents coordinates smaller     * than the minimum resolution of the antialiasing rasterizer as     * specified by the {@code getMinimumAAPenWidth()} method.     * <p>     * Upon returning, this method will fill the {@code bbox} parameter     * with 4 values indicating the bounds of the iteration of the     * tile generator.     * The iteration order of the tiles will be as specified by the     * pseudo-code:     * <pre>     *     for (y = bbox[1]; y < bbox[3]; y += tileheight) {     *         for (x = bbox[0]; x < bbox[2]; x += tilewidth) {     *         }     *     }     * </pre>     * If there is no output to be rendered, this method may return     * null.     *     * @param s the shape to be rendered (fill or draw)     * @param at the transform to be applied to the shape and the     *           stroke attributes     * @param clip the current clip in effect in device coordinates     * @param bs if non-null, a {@code BasicStroke} whose attributes     *           should be applied to this operation     * @param thin true if the transformed stroke attributes are smaller     *             than the minimum dropout pen width     * @param normalize true if the {@code VALUE_STROKE_NORMALIZE}     *                  {@code RenderingHint} is in effect     * @param bbox returns the bounds of the iteration     * @return the {@code AATileGenerator} instance to be consulted     *         for tile coverages, or null if there is no output to render     * @since 1.7     */    public abstract AATileGenerator getAATileGenerator(Shape s,                                                       AffineTransform at,                                                       Region clip,                                                       BasicStroke bs,                                                       boolean thin,                                                       boolean normalize,                                                       int bbox[]);     /**     * Construct an antialiased tile generator for the given parallelogram     * store the bounds of the tile iteration in the bbox parameter.     * The parallelogram is specified as a starting point and 2 delta     * vectors that indicate the slopes of the 2 pairs of sides of the     * parallelogram.     * The 4 corners of the parallelogram are defined by the 4 points:     * <ul>     * <li> {@code x}, {@code y}     * <li> {@code x+dx1}, {@code y+dy1}     * <li> {@code x+dx1+dx2}, {@code y+dy1+dy2}     * <li> {@code x+dx2}, {@code y+dy2}     * </ul>     * The {@code lw1} and {@code lw2} parameters provide a specification     * for an optionally stroked parallelogram if they are positive numbers.     * The {@code lw1} parameter is the ratio of the length of the {@code dx1},     * {@code dx2} delta vector to half of the line width in that same     * direction.     * The {@code lw2} parameter provides the same ratio for the other delta     * vector.     * If {@code lw1} and {@code lw2} are both greater than zero, then     * the parallelogram figure is doubled by both expanding and contracting     * each delta vector by its corresponding {@code lw} value.     * If either (@code lw1) or {@code lw2} are also greater than 1, then     * the inner (contracted) parallelogram disappears and the figure is     * simply a single expanded parallelogram.     * The {@code clip} parameter specifies the current clip in effect     * in device coordinates and can be used to prune the data for the     * operation, but the renderer is not required to perform any     * clipping.     * <p>     * Upon returning, this method will fill the {@code bbox} parameter     * with 4 values indicating the bounds of the iteration of the     * tile generator.     * The iteration order of the tiles will be as specified by the     * pseudo-code:     * <pre>     *     for (y = bbox[1]; y < bbox[3]; y += tileheight) {     *         for (x = bbox[0]; x < bbox[2]; x += tilewidth) {     *         }     *     }     * </pre>     * If there is no output to be rendered, this method may return     * null.     *     * @param x the X coordinate of the first corner of the parallelogram     * @param y the Y coordinate of the first corner of the parallelogram     * @param dx1 the X coordinate delta of the first leg of the parallelogram     * @param dy1 the Y coordinate delta of the first leg of the parallelogram     * @param dx2 the X coordinate delta of the second leg of the parallelogram     * @param dy2 the Y coordinate delta of the second leg of the parallelogram     * @param lw1 the line width ratio for the first leg of the parallelogram     * @param lw2 the line width ratio for the second leg of the parallelogram     * @param clip the current clip in effect in device coordinates     * @param bbox returns the bounds of the iteration     * @return the {@code AATileGenerator} instance to be consulted     *         for tile coverages, or null if there is no output to render     * @since 1.7     */    public abstract AATileGenerator getAATileGenerator(double x, double y,                                                       double dx1, double dy1,                                                       double dx2, double dy2,                                                       double lw1, double lw2,                                                       Region clip,                                                       int bbox[]);     /**     * Returns the minimum pen width that the antialiasing rasterizer     * can represent without dropouts occuring.     * @since 1.7     */    public abstract float getMinimumAAPenSize();     /**     * Utility method to feed a {@link PathConsumer2D} object from a     * given {@link PathIterator}.     * This method deals with the details of running the iterator and     * feeding the consumer a segment at a time.     */    public static void feedConsumer(PathIterator pi, PathConsumer2D consumer) {        float coords[] = new float[6];        while (!pi.isDone()) {            switch (pi.currentSegment(coords)) {            case PathIterator.SEG_MOVETO:                consumer.moveTo(coords[0], coords[1]);                break;            case PathIterator.SEG_LINETO:                consumer.lineTo(coords[0], coords[1]);                break;            case PathIterator.SEG_QUADTO:                consumer.quadTo(coords[0], coords[1],                                coords[2], coords[3]);                break;            case PathIterator.SEG_CUBICTO:                consumer.curveTo(coords[0], coords[1],                                 coords[2], coords[3],                                 coords[4], coords[5]);                break;            case PathIterator.SEG_CLOSE:                consumer.closePath();                break;            }            pi.next();        }    }     static class Tracer extends RenderingEngine {        RenderingEngine target;        String name;         public Tracer(RenderingEngine target) {            this.target = target;            name = target.getClass().getName();        }         public Shape createStrokedShape(Shape src,                                        float width,                                        int caps,                                        int join,                                        float miterlimit,                                        float dashes[],                                        float dashphase)        {            System.out.println(name+".createStrokedShape("+                               src.getClass().getName()+", "+                               "width = "+width+", "+                               "caps = "+caps+", "+                               "join = "+join+", "+                               "miter = "+miterlimit+", "+                               "dashes = "+dashes+", "+                               "dashphase = "+dashphase+")");            return target.createStrokedShape(src,                                             width, caps, join, miterlimit,                                             dashes, dashphase);        }         public void strokeTo(Shape src,                             AffineTransform at,                             BasicStroke bs,                             boolean thin,                             boolean normalize,                             boolean antialias,                             PathConsumer2D consumer)        {            System.out.println(name+".strokeTo("+                               src.getClass().getName()+", "+                               at+", "+                               bs+", "+                               (thin ? "thin" : "wide")+", "+                               (normalize ? "normalized" : "pure")+", "+                               (antialias ? "AA" : "non-AA")+", "+                               consumer.getClass().getName()+")");            target.strokeTo(src, at, bs, thin, normalize, antialias, consumer);        }         public float getMinimumAAPenSize() {            System.out.println(name+".getMinimumAAPenSize()");            return target.getMinimumAAPenSize();        }         public AATileGenerator getAATileGenerator(Shape s,                                                  AffineTransform at,                                                  Region clip,                                                  BasicStroke bs,                                                  boolean thin,                                                  boolean normalize,                                                  int bbox[])        {            System.out.println(name+".getAATileGenerator("+                               s.getClass().getName()+", "+                               at+", "+                               clip+", "+                               bs+", "+                               (thin ? "thin" : "wide")+", "+                               (normalize ? "normalized" : "pure")+")");            return target.getAATileGenerator(s, at, clip,                                             bs, thin, normalize,                                             bbox);        }        public AATileGenerator getAATileGenerator(double x, double y,                                                  double dx1, double dy1,                                                  double dx2, double dy2,                                                  double lw1, double lw2,                                                  Region clip,                                                  int bbox[])        {            System.out.println(name+".getAATileGenerator("+                               x+", "+y+", "+                               dx1+", "+dy1+", "+                               dx2+", "+dy2+", "+                               lw1+", "+lw2+", "+                               clip+")");            return target.getAATileGenerator(x, y,                                             dx1, dy1,                                             dx2, dy2,                                             lw1, lw2,                                             clip, bbox);        }    }}