1 /*
   2  * Copyright (c) 2013, 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.util.Arrays;
  30 import java.util.List;
  31 import sun.misc.SoftCache;
  32 
  33 public class MultiResolutionToolkitImage extends ToolkitImage implements MultiResolutionImage {
  34 
  35     Image resolutionVariant;
  36 
  37     public MultiResolutionToolkitImage(Image lowResolutionImage, Image resolutionVariant) {
  38         super(lowResolutionImage.getSource());
  39         this.resolutionVariant = resolutionVariant;
  40     }
  41 
  42     @Override
  43     public Image getResolutionVariant(int width, int height) {
  44         return ((width <= getWidth() && height <= getHeight()))
  45                 ? this : resolutionVariant;
  46     }
  47 
  48     public Image getResolutionVariant() {
  49         return resolutionVariant;
  50     }
  51 
  52     @Override
  53     public List<Image> getResolutionVariants() {
  54         return Arrays.<Image>asList(this, resolutionVariant);
  55     }
  56 
  57     private static final int BITS_INFO = ImageObserver.SOMEBITS
  58             | ImageObserver.FRAMEBITS | ImageObserver.ALLBITS;
  59 
  60     private static class ObserverCache {
  61 
  62         static final SoftCache INSTANCE = new SoftCache();
  63     }
  64 
  65     public static ImageObserver getResolutionVariantObserver(
  66             final Image image, final ImageObserver observer,
  67             final int imgWidth, final int imgHeight,
  68             final int rvWidth, final int rvHeight) {
  69         return getResolutionVariantObserver(image, observer,
  70                 imgWidth, imgHeight, rvWidth, rvHeight, false);
  71     }
  72 
  73     public static ImageObserver getResolutionVariantObserver(
  74             final Image image, final ImageObserver observer,
  75             final int imgWidth, final int imgHeight,
  76             final int rvWidth, final int rvHeight, boolean concatenateInfo) {
  77 
  78         if (observer == null) {
  79             return null;
  80         }
  81 
  82         synchronized (ObserverCache.INSTANCE) {
  83             ImageObserver o = (ImageObserver) ObserverCache.INSTANCE.get(image);
  84 
  85             if (o == null) {
  86 
  87                 o = (Image resolutionVariant, int flags,
  88                         int x, int y, int width, int height) -> {
  89 
  90                             if ((flags & (ImageObserver.WIDTH | BITS_INFO)) != 0) {
  91                                 width = (width + 1) / 2;
  92                             }
  93 
  94                             if ((flags & (ImageObserver.HEIGHT | BITS_INFO)) != 0) {
  95                                 height = (height + 1) / 2;
  96                             }
  97 
  98                             if ((flags & BITS_INFO) != 0) {
  99                                 x /= 2;
 100                                 y /= 2;
 101                             }
 102 
 103                             if(concatenateInfo){
 104                                 flags &= ((ToolkitImage) image).
 105                                         getImageRep().check(null);
 106                             }
 107 
 108                             return observer.imageUpdate(
 109                                     image, flags, x, y, width, height);
 110                         };
 111 
 112                 ObserverCache.INSTANCE.put(image, o);
 113             }
 114             return o;
 115         }
 116     }
 117 }