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 java.util.function.Function;
  33 import sun.awt.SoftCache;
  34 
  35 public class MultiResolutionToolkitImage extends ToolkitImage implements MultiResolutionImage {
  36 
  37     Image resolutionVariant;
  38 
  39     public MultiResolutionToolkitImage(Image lowResolutionImage, Image resolutionVariant) {
  40         super(lowResolutionImage.getSource());
  41         this.resolutionVariant = resolutionVariant;
  42     }
  43 
  44     @Override
  45     public Image getResolutionVariant(double destWidth, double destHeight) {
  46         checkSize(destWidth, destHeight);
  47         return ((destWidth <= getWidth() && destHeight <= getHeight()))
  48                 ? this : resolutionVariant;
  49     }
  50 
  51     public static Image map(MultiResolutionToolkitImage mrImage,
  52                             Function<Image, Image> mapper) {
  53         Image baseImage = mapper.apply(mrImage);
  54         Image rvImage = mapper.apply(mrImage.resolutionVariant);
  55         return new MultiResolutionToolkitImage(baseImage, rvImage);
  56     }
  57 
  58     private static void checkSize(double width, double height) {
  59         if (width <= 0 || height <= 0) {
  60             throw new IllegalArgumentException(String.format(
  61                     "Width (%s) or height (%s) cannot be <= 0", width, height));
  62         }
  63 
  64         if (!Double.isFinite(width) || !Double.isFinite(height)) {
  65             throw new IllegalArgumentException(String.format(
  66                     "Width (%s) or height (%s) is not finite", width, height));
  67         }
  68     }
  69 
  70     public Image getResolutionVariant() {
  71         return resolutionVariant;
  72     }
  73 
  74     @Override
  75     public List<Image> getResolutionVariants() {
  76         return Arrays.<Image>asList(this, resolutionVariant);
  77     }
  78 
  79     private static final int BITS_INFO = ImageObserver.SOMEBITS
  80             | ImageObserver.FRAMEBITS | ImageObserver.ALLBITS;
  81 
  82     private static class ObserverCache {
  83 
  84         @SuppressWarnings("deprecation")
  85         static final SoftCache INSTANCE = new SoftCache();
  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) {
  92         return getResolutionVariantObserver(image, observer,
  93                 imgWidth, imgHeight, rvWidth, rvHeight, false);
  94     }
  95 
  96     public static ImageObserver getResolutionVariantObserver(
  97             final Image image, final ImageObserver observer,
  98             final int imgWidth, final int imgHeight,
  99             final int rvWidth, final int rvHeight, boolean concatenateInfo) {
 100 
 101         if (observer == null) {
 102             return null;
 103         }
 104 
 105         synchronized (ObserverCache.INSTANCE) {
 106             ImageObserver o = (ImageObserver) ObserverCache.INSTANCE.get(observer);
 107 
 108             if (o == null) {
 109 
 110                 o = (Image resolutionVariant, int flags,
 111                         int x, int y, int width, int height) -> {
 112 
 113                             if ((flags & (ImageObserver.WIDTH | BITS_INFO)) != 0) {
 114                                 width = (width + 1) / 2;
 115                             }
 116 
 117                             if ((flags & (ImageObserver.HEIGHT | BITS_INFO)) != 0) {
 118                                 height = (height + 1) / 2;
 119                             }
 120 
 121                             if ((flags & BITS_INFO) != 0) {
 122                                 x /= 2;
 123                                 y /= 2;
 124                             }
 125 
 126                             if(concatenateInfo){
 127                                 flags &= ((ToolkitImage) image).
 128                                         getImageRep().check(null);
 129                             }
 130 
 131                             return observer.imageUpdate(
 132                                     image, flags, x, y, width, height);
 133                         };
 134 
 135                 ObserverCache.INSTANCE.put(observer, o);
 136             }
 137             return o;
 138         }
 139     }
 140 }