1 /*
   2  * Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package sun.awt.image;
  26 
  27 import java.awt.Image;
  28 import java.awt.image.ImageObserver;
  29 import java.awt.image.MultiResolutionImage;
  30 import java.util.Arrays;
  31 import java.util.List;
  32 import sun.misc.SoftCache;
  33 
  34 public class MultiResolutionToolkitImage extends ToolkitImage implements MultiResolutionImage {
  35 
  36     Image resolutionVariant;
  37 
  38     public MultiResolutionToolkitImage(Image lowResolutionImage, Image resolutionVariant) {
  39         super(lowResolutionImage.getSource());
  40         this.resolutionVariant = resolutionVariant;
  41     }
  42 
  43     @Override
  44     public Image getResolutionVariant(double destWidth, double destHeight) {
  45         checkSize(destWidth, destHeight);
  46         return ((destWidth <= getWidth() && destHeight <= getHeight()))
  47                 ? this : resolutionVariant;
  48     }
  49 
  50     private static void checkSize(double width, double height) {
  51         if (width <= 0 || height <= 0) {
  52             throw new IllegalArgumentException(String.format(
  53                     "Width (%s) or height (%s) cannot be <= 0", width, height));
  54         }
  55 
  56         if (!Double.isFinite(width) || !Double.isFinite(height)) {
  57             throw new IllegalArgumentException(String.format(
  58                     "Width (%s) or height (%s) is not finite", width, height));
  59         }
  60     }
  61 
  62     public Image getResolutionVariant() {
  63         return resolutionVariant;
  64     }
  65 
  66     @Override
  67     public List<Image> getResolutionVariants() {
  68         return Arrays.<Image>asList(this, resolutionVariant);
  69     }
  70 
  71     private static final int BITS_INFO = ImageObserver.SOMEBITS
  72             | ImageObserver.FRAMEBITS | ImageObserver.ALLBITS;
  73 
  74     private static class ObserverCache {
  75 
  76         @SuppressWarnings("deprecation")
  77         static final SoftCache INSTANCE = new SoftCache();
  78     }
  79 
  80     public static ImageObserver getResolutionVariantObserver(
  81             final Image image, final ImageObserver observer,
  82             final int imgWidth, final int imgHeight,
  83             final int rvWidth, final int rvHeight) {
  84         return getResolutionVariantObserver(image, observer,
  85                 imgWidth, imgHeight, rvWidth, rvHeight, false);
  86     }
  87 
  88     public static ImageObserver getResolutionVariantObserver(
  89             final Image image, final ImageObserver observer,
  90             final int imgWidth, final int imgHeight,
  91             final int rvWidth, final int rvHeight, boolean concatenateInfo) {
  92 
  93         if (observer == null) {
  94             return null;
  95         }
  96 
  97         synchronized (ObserverCache.INSTANCE) {
  98             ImageObserver o = (ImageObserver) ObserverCache.INSTANCE.get(observer);
  99 
 100             if (o == null) {
 101 
 102                 o = (Image resolutionVariant, int flags,
 103                         int x, int y, int width, int height) -> {
 104 
 105                             if ((flags & (ImageObserver.WIDTH | BITS_INFO)) != 0) {
 106                                 width = (width + 1) / 2;
 107                             }
 108 
 109                             if ((flags & (ImageObserver.HEIGHT | BITS_INFO)) != 0) {
 110                                 height = (height + 1) / 2;
 111                             }
 112 
 113                             if ((flags & BITS_INFO) != 0) {
 114                                 x /= 2;
 115                                 y /= 2;
 116                             }
 117 
 118                             if(concatenateInfo){
 119                                 flags &= ((ToolkitImage) image).
 120                                         getImageRep().check(null);
 121                             }
 122 
 123                             return observer.imageUpdate(
 124                                     image, flags, x, y, width, height);
 125                         };
 126 
 127                 ObserverCache.INSTANCE.put(observer, o);
 128             }
 129             return o;
 130         }
 131     }
 132 }