1 /* 2 * Copyright 2022 Google LLC. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef skgpu_MutableTextureState_DEFINED 9 #define skgpu_MutableTextureState_DEFINED 10 11 #include "include/core/SkRefCnt.h" 12 #include "include/core/SkTypes.h" 13 #include "include/private/base/SkAnySubclass.h" 14 15 #include <cstddef> 16 17 namespace skgpu { 18 enum class BackendApi : unsigned int; 19 class MutableTextureStateData; 20 21 /** 22 * Since Skia and clients can both modify gpu textures and their connected state, Skia needs a way 23 * for clients to inform us if they have modifiend any of this state. In order to not need setters 24 * for every single API and state, we use this class to be a generic wrapper around all the mutable 25 * state. This class is used for calls that inform Skia of these texture/image state changes by the 26 * client as well as for requesting state changes to be done by Skia. The backend specific state 27 * that is wrapped by this class are located in files like: 28 * - include/gpu/vk/VulkanMutableTextureState.h 29 */ 30 class SK_API MutableTextureState : public SkRefCnt { 31 public: 32 MutableTextureState(); 33 ~MutableTextureState() override; 34 35 MutableTextureState(const MutableTextureState& that); 36 37 MutableTextureState& operator=(const MutableTextureState& that); 38 39 void set(const MutableTextureState& that); 40 backend()41 BackendApi backend() const { return fBackend; } 42 43 // Returns true if the backend mutable state has been initialized. isValid()44 bool isValid() const { return fIsValid; } 45 46 private: 47 friend class MutableTextureStateData; 48 friend class MutableTextureStatePriv; 49 // Size determined by looking at the MutableTextureStateData subclasses, then 50 // guessing-and-checking. Compiler will complain if this is too small - in that case, 51 // just increase the number. 52 inline constexpr static size_t kMaxSubclassSize = 16; 53 using AnyStateData = SkAnySubclass<MutableTextureStateData, kMaxSubclassSize>; 54 55 template <typename StateData> MutableTextureState(BackendApi api,const StateData & data)56 MutableTextureState(BackendApi api, const StateData& data) : fBackend(api), fIsValid(true) { 57 fStateData.emplace<StateData>(data); 58 } 59 60 AnyStateData fStateData; 61 62 BackendApi fBackend; 63 bool fIsValid; 64 }; 65 66 } // namespace skgpu 67 68 #endif // skgpu_MutableTextureState_DEFINED 69