1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.util.imagepool; 18 19 import com.android.tools.layoutlib.annotations.NotNull; 20 21 import java.awt.Graphics2D; 22 import java.awt.Image; 23 import java.awt.image.BufferedImage; 24 import java.awt.image.ImageObserver; 25 import java.util.function.Consumer; 26 27 /** 28 * Simplified version of image pool that exists in Studio. 29 * 30 * Lacks: 31 * - PhantomReference and FinalizableReference to recognize the death of references automatically. 32 * (Meaning devs need to be more deligent in dispose.) 33 * Has: 34 * + Debugger that allows us to better trace where image is being leaked in stack. 35 */ 36 public interface ImagePool { 37 38 /** 39 * Returns a new image of width w and height h. 40 */ 41 @NotNull acquire(final int w, final int h, final int type)42 Image acquire(final int w, final int h, final int type); 43 44 /** 45 * Disposes the image pool, releasing all the references to the buffered images. 46 */ dispose()47 void dispose(); 48 49 /** 50 * Interface that represents a buffered image. Using this wrapper allows us ot better track 51 * memory usages around BufferedImage. When all of it's references are removed, it will 52 * automatically be pooled back into the image pool for re-use. 53 */ 54 interface Image { 55 56 /** 57 * Same as {@link BufferedImage#setRGB(int, int, int, int, int[], int, int)} 58 */ setRGB(int x, int y, int width, int height, int[] colors, int offset, int stride)59 void setRGB(int x, int y, int width, int height, int[] colors, int offset, int stride); 60 61 /** 62 * Same as {@link Graphics2D#drawImage(java.awt.Image, int, int, ImageObserver)} 63 */ drawImage(Graphics2D graphics, int x, int y, ImageObserver o)64 void drawImage(Graphics2D graphics, int x, int y, ImageObserver o); 65 66 /** 67 * Image orientation. It's not used at the moment. To be used later. 68 */ 69 enum Orientation { 70 NONE, 71 CW_90 72 } 73 getWidth()74 int getWidth(); getHeight()75 int getHeight(); 76 } 77 78 /** 79 * Policy for how to set up the memory pool. 80 */ 81 class ImagePoolPolicy { 82 83 public final int[] mBucketSizes; 84 public final int[] mNumberOfCopies; 85 public final long mBucketMaxCacheSize; 86 87 /** 88 * @param bucketPixelSizes - list of pixel sizes to bucket (categorize) images. The list 89 * must be sorted (low to high). 90 * @param numberOfCopies - Allows users to create multiple copies of the bucket. It is 91 * recommended to create more copies for smaller images to avoid fragmentation in memory. 92 * It must match the size of bucketPixelSizes. 93 * @param bucketMaxCacheByteSize - Maximum cache byte sizes image pool is allowed to hold onto 94 * in memory. 95 */ ImagePoolPolicy( int[] bucketPixelSizes, int[] numberOfCopies, long bucketMaxCacheByteSize)96 public ImagePoolPolicy( 97 int[] bucketPixelSizes, int[] numberOfCopies, long bucketMaxCacheByteSize) { 98 assert bucketPixelSizes.length == numberOfCopies.length; 99 mBucketSizes = bucketPixelSizes; 100 mNumberOfCopies = numberOfCopies; 101 mBucketMaxCacheSize = bucketMaxCacheByteSize; 102 } 103 } 104 } 105