1 // Copyright 2013 The Flutter Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef FLUTTER_SHELL_GPU_GPU_SURFACE_SOFTWARE_DELEGATE_H_ 6 #define FLUTTER_SHELL_GPU_GPU_SURFACE_SOFTWARE_DELEGATE_H_ 7 8 #include "flutter/flow/embedded_views.h" 9 #include "flutter/fml/macros.h" 10 #include "third_party/skia/include/core/SkSurface.h" 11 12 namespace flutter { 13 14 //------------------------------------------------------------------------------ 15 /// @brief Interface implemented by all platform surfaces that can present 16 /// a software backing store to the "screen". The GPU surface 17 /// abstraction (which abstracts the client rendering API) uses this 18 /// delegation pattern to tell the platform surface (which abstracts 19 /// how backing stores fulfilled by the selected client rendering 20 /// API end up on the "screen" on a particular platform) when the 21 /// rasterizer needs to allocate and present the software backing 22 /// store. 23 /// 24 /// @see |IOSurfaceSoftware|, |AndroidSurfaceSoftware|, 25 /// |EmbedderSurfaceSoftware|. 26 /// 27 class GPUSurfaceSoftwareDelegate { 28 public: 29 //---------------------------------------------------------------------------- 30 /// @brief Called when the GPU surface needs a new buffer to render a new 31 /// frame into. 32 /// 33 /// @param[in] size The size of the frame. 34 /// 35 /// @return A raster surface returned by the platform. 36 /// 37 virtual sk_sp<SkSurface> AcquireBackingStore(const SkISize& size) = 0; 38 39 //---------------------------------------------------------------------------- 40 /// @brief Called by the platform when a frame has been rendered into the 41 /// backing store and the platform must display it on-screen. 42 /// 43 /// @param[in] backing_store The software backing store to present. 44 /// 45 /// @return Returns if the platform could present the backing store onto 46 /// the screen. 47 /// 48 virtual bool PresentBackingStore(sk_sp<SkSurface> backing_store) = 0; 49 50 //---------------------------------------------------------------------------- 51 /// @brief Gets the view embedder that controls how the Flutter layer 52 /// hierarchy split into multiple chunks should be composited back 53 /// on-screen. This field is optional and the Flutter rasterizer 54 /// will render into a single on-screen surface if this call 55 /// returns a null external view embedder. 56 /// 57 /// @return The external view embedder, or, null if Flutter is rendering 58 /// into a single on-screen surface. 59 /// 60 virtual ExternalViewEmbedder* GetExternalViewEmbedder() = 0; 61 }; 62 63 } // namespace flutter 64 65 #endif // FLUTTER_SHELL_GPU_GPU_SURFACE_SOFTWARE_DELEGATE_H_ 66