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 #pragma once 17 18 namespace gfxstream { 19 20 class ColorBuffer; 21 22 // This class implements async readback of ColorBuffers on both the FrameBuffer 23 // posting thread and a separate worker thread. 24 class ReadbackWorker { 25 public: 26 virtual ~ReadbackWorker() = default; 27 28 virtual void init() = 0; 29 30 // Enables readback of the given display. 31 virtual void initReadbackForDisplay(uint32_t displayId, uint32_t w, uint32_t h) = 0; 32 33 // Enables readback of the given display. 34 virtual void deinitReadbackForDisplay(uint32_t displayId) = 0; 35 36 enum class DoNextReadbackResult { 37 OK_NOT_READY_FOR_READ, 38 39 OK_READY_FOR_READ, 40 }; 41 42 // doNextReadback(): Call this from the emugl FrameBuffer::post thread 43 // or similar rendering thread. 44 // This will trigger an async glReadPixels of the current framebuffer. 45 // The post callback of Framebuffer will also be triggered, but 46 // in async mode it should do minimal work that involves |fbImage|. 47 // |repaint|: flag to prime async readback with multiple iterations 48 // so that the consumer of readback doesn't lag behind. 49 // |readbackBgra|: Whether to force the readback format as GL_BGRA_EXT, 50 // so that we get (depending on driver quality, heh) a gpu conversion of the 51 // readback image that is suitable for webrtc, which expects formats like that. 52 virtual DoNextReadbackResult doNextReadback(uint32_t displayId, 53 ColorBuffer* cb, 54 void* fbImage, 55 bool repaint, 56 bool readbackBgra) = 0; 57 58 // Retrieves the latest framebuffer that has been posted and read with 59 // doNextReadback. This is meant for apps like video encoding to use as 60 // input; they will need to do synchronized communication with the thread 61 // ReadbackWorker is running on. 62 virtual void getPixels(uint32_t displayId, void* out, uint32_t bytes) = 0; 63 64 // Duplicates the last frame and generates a post events if 65 // there are no read events active. 66 // This is usually called when there was no doNextReadback activity 67 // for a few ms, to guarantee that end users see the final frame. 68 enum class FlushResult { 69 FAIL, 70 71 OK_NOT_READY_FOR_READ, 72 73 OK_READY_FOR_READ, 74 }; 75 76 virtual FlushResult flushPipeline(uint32_t displayId) = 0; 77 }; 78 79 } // namespace gfxstream 80