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      1 /*
      2  * Copyright (C) 2012 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 com.android.gallery3d.ui;
     18 
     19 import com.android.gallery3d.ui.GLRoot.OnGLIdleListener;
     20 
     21 import java.util.ArrayDeque;
     22 
     23 public class TextureUploader implements OnGLIdleListener {
     24     private static final int INIT_CAPACITY = 64;
     25     private static final int QUOTA_PER_FRAME = 1;
     26 
     27     private final ArrayDeque<UploadedTexture> mFgTextures =
     28             new ArrayDeque<UploadedTexture>(INIT_CAPACITY);
     29     private final ArrayDeque<UploadedTexture> mBgTextures =
     30             new ArrayDeque<UploadedTexture>(INIT_CAPACITY);
     31     private final GLRoot mGLRoot;
     32     private transient boolean mIsQueued = false;
     33 
     34     public TextureUploader(GLRoot root) {
     35         mGLRoot = root;
     36     }
     37 
     38     public synchronized void clear() {
     39         while (!mFgTextures.isEmpty()) {
     40             mFgTextures.pop().setIsUploading(false);
     41         }
     42         while (!mBgTextures.isEmpty()) {
     43             mBgTextures.pop().setIsUploading(false);
     44         }
     45     }
     46 
     47     // caller should hold synchronized on "this"
     48     private void queueSelfIfNeed() {
     49         if (mIsQueued) return;
     50         mIsQueued = true;
     51         mGLRoot.addOnGLIdleListener(this);
     52     }
     53 
     54     public synchronized void addBgTexture(UploadedTexture t) {
     55         if (t.isContentValid()) return;
     56         mBgTextures.addLast(t);
     57         t.setIsUploading(true);
     58         queueSelfIfNeed();
     59     }
     60 
     61     public synchronized void addFgTexture(UploadedTexture t) {
     62         if (t.isContentValid()) return;
     63         mFgTextures.addLast(t);
     64         t.setIsUploading(true);
     65         queueSelfIfNeed();
     66     }
     67 
     68     private int upload(GLCanvas canvas, ArrayDeque<UploadedTexture> deque,
     69             int uploadQuota, boolean isBackground) {
     70         while (uploadQuota > 0) {
     71             UploadedTexture t;
     72             synchronized (this) {
     73                 if (deque.isEmpty()) break;
     74                 t = deque.removeFirst();
     75                 t.setIsUploading(false);
     76                 if (t.isContentValid()) continue;
     77 
     78                 // this has to be protected by the synchronized block
     79                 // to prevent the inner bitmap get recycled
     80                 t.updateContent(canvas);
     81             }
     82 
     83             // It will took some more time for a texture to be drawn for
     84             // the first time.
     85             // Thus, when scrolling, if a new column appears on screen,
     86             // it may cause a UI jank even these textures are uploaded.
     87             if (isBackground) t.draw(canvas, 0, 0);
     88             --uploadQuota;
     89         }
     90         return uploadQuota;
     91     }
     92 
     93     @Override
     94     public boolean onGLIdle(GLCanvas canvas, boolean renderRequested) {
     95         int uploadQuota = QUOTA_PER_FRAME;
     96         uploadQuota = upload(canvas, mFgTextures, uploadQuota, false);
     97         if (uploadQuota < QUOTA_PER_FRAME) mGLRoot.requestRender();
     98         upload(canvas, mBgTextures, uploadQuota, true);
     99         synchronized (this) {
    100             mIsQueued = !mFgTextures.isEmpty() || !mBgTextures.isEmpty();
    101             return mIsQueued;
    102         }
    103     }
    104 }
    105