1 /*
2 * Copyright (C) 2017 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 #include "HWComposerBufferCache.h"
18
19 #include <gui/BufferQueue.h>
20
21 namespace android {
22
HWComposerBufferCache()23 HWComposerBufferCache::HWComposerBufferCache()
24 {
25 mBuffers.reserve(BufferQueue::NUM_BUFFER_SLOTS);
26 }
27
getHwcBuffer(int slot,const sp<GraphicBuffer> & buffer,uint32_t * outSlot,sp<GraphicBuffer> * outBuffer)28 void HWComposerBufferCache::getHwcBuffer(int slot,
29 const sp<GraphicBuffer>& buffer,
30 uint32_t* outSlot, sp<GraphicBuffer>* outBuffer)
31 {
32 if (slot == BufferQueue::INVALID_BUFFER_SLOT || slot < 0) {
33 // default to slot 0
34 slot = 0;
35 }
36
37 if (static_cast<size_t>(slot) >= mBuffers.size()) {
38 mBuffers.resize(slot + 1);
39 }
40
41 *outSlot = slot;
42
43 if (mBuffers[slot] == buffer) {
44 // already cached in HWC, skip sending the buffer
45 *outBuffer = nullptr;
46 } else {
47 *outBuffer = buffer;
48
49 // update cache
50 mBuffers[slot] = buffer;
51 }
52 }
53
54 } // namespace android
55