1/* 2 * Copyright (C) 2010 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 17package android.view; 18 19import android.annotation.NonNull; 20import android.annotation.Nullable; 21import android.util.Pools.SynchronizedPool; 22 23/** 24 * An implementation of a GL canvas that records drawing operations. 25 * This is intended for use with a DisplayList. This class keeps a list of all the Paint and 26 * Bitmap objects that it draws, preventing the backing memory of Bitmaps from being freed while 27 * the DisplayList is still holding a native reference to the memory. 28 */ 29class GLES20RecordingCanvas extends GLES20Canvas { 30 // The recording canvas pool should be large enough to handle a deeply nested 31 // view hierarchy because display lists are generated recursively. 32 private static final int POOL_LIMIT = 25; 33 34 private static final SynchronizedPool<GLES20RecordingCanvas> sPool = 35 new SynchronizedPool<GLES20RecordingCanvas>(POOL_LIMIT); 36 37 RenderNode mNode; 38 39 private GLES20RecordingCanvas() { 40 super(); 41 } 42 43 static GLES20RecordingCanvas obtain(@NonNull RenderNode node) { 44 if (node == null) throw new IllegalArgumentException("node cannot be null"); 45 GLES20RecordingCanvas canvas = sPool.acquire(); 46 if (canvas == null) { 47 canvas = new GLES20RecordingCanvas(); 48 } 49 canvas.mNode = node; 50 return canvas; 51 } 52 53 void recycle() { 54 mNode = null; 55 sPool.release(this); 56 } 57 58 long finishRecording() { 59 return nFinishRecording(mRenderer); 60 } 61 62 @Override 63 public boolean isRecordingFor(Object o) { 64 return o == mNode; 65 } 66} 67