/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim:set ts=2 sw=2 sts=2 et cindent: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #ifndef MOZILLA_DOM_OFFSCREENCANVAS_H_ #define MOZILLA_DOM_OFFSCREENCANVAS_H_ #include "mozilla/DOMEventTargetHelper.h" #include "mozilla/layers/LayersTypes.h" #include "mozilla/RefPtr.h" #include "CanvasRenderingContextHelper.h" #include "nsCycleCollectionParticipant.h" struct JSContext; namespace mozilla { class ErrorResult; namespace layers { class AsyncCanvasRenderer; class CanvasClient; } // namespace layers namespace dom { class Blob; class ImageBitmap; // This is helper class for transferring OffscreenCanvas to worker thread. // Because OffscreenCanvas is not thread-safe. So we cannot pass Offscreen- // Canvas to worker thread directly. Thus, we create this helper class and // store necessary data in it then pass it to worker thread. struct OffscreenCanvasCloneData final { OffscreenCanvasCloneData(layers::AsyncCanvasRenderer* aRenderer, uint32_t aWidth, uint32_t aHeight, layers::LayersBackend aCompositorBackend, bool aNeutered, bool aIsWriteOnly); ~OffscreenCanvasCloneData(); RefPtr<layers::AsyncCanvasRenderer> mRenderer; uint32_t mWidth; uint32_t mHeight; layers::LayersBackend mCompositorBackendType; bool mNeutered; bool mIsWriteOnly; }; class OffscreenCanvas final : public DOMEventTargetHelper , public CanvasRenderingContextHelper { public: NS_DECL_ISUPPORTS_INHERITED NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(OffscreenCanvas, DOMEventTargetHelper) OffscreenCanvas(nsIGlobalObject* aGlobal, uint32_t aWidth, uint32_t aHeight, layers::LayersBackend aCompositorBackend, layers::AsyncCanvasRenderer* aRenderer); nsCOMPtr<nsIGlobalObject> GetParentObject() const { return GetOwnerGlobal(); } virtual JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override; static already_AddRefed<OffscreenCanvas> Constructor(const GlobalObject& aGlobal, uint32_t aWidth, uint32_t aHeight, ErrorResult& aRv); void ClearResources(); uint32_t Width() const { return mWidth; } uint32_t Height() const { return mHeight; } void SetWidth(uint32_t aWidth, ErrorResult& aRv) { if (mNeutered) { aRv.Throw(NS_ERROR_FAILURE); return; } if (mWidth != aWidth) { mWidth = aWidth; CanvasAttrChanged(); } } void SetHeight(uint32_t aHeight, ErrorResult& aRv) { if (mNeutered) { aRv.Throw(NS_ERROR_FAILURE); return; } if (mHeight != aHeight) { mHeight = aHeight; CanvasAttrChanged(); } } already_AddRefed<ImageBitmap> TransferToImageBitmap(); already_AddRefed<Promise> ToBlob(JSContext* aCx, const nsAString& aType, JS::Handle<JS::Value> aParams, ErrorResult& aRv); nsICanvasRenderingContextInternal* GetContext() const { return mCurrentContext; } already_AddRefed<gfx::SourceSurface> GetSurfaceSnapshot(bool* aPremultAlpha = nullptr); static already_AddRefed<OffscreenCanvas> CreateFromCloneData(nsIGlobalObject* aGlobal, OffscreenCanvasCloneData* aData); static bool PrefEnabled(JSContext* aCx, JSObject* aObj); // Return true on main-thread, and return gfx.offscreencanvas.enabled // on worker thread. static bool PrefEnabledOnWorkerThread(JSContext* aCx, JSObject* aObj); OffscreenCanvasCloneData* ToCloneData(); void CommitFrameToCompositor(); virtual bool GetOpaqueAttr() override { return false; } virtual nsIntSize GetWidthHeight() override { return nsIntSize(mWidth, mHeight); } virtual already_AddRefed<nsICanvasRenderingContextInternal> CreateContext(CanvasContextType aContextType) override; virtual already_AddRefed<nsISupports> GetContext(JSContext* aCx, const nsAString& aContextId, JS::Handle<JS::Value> aContextOptions, ErrorResult& aRv) override; void SetNeutered() { mNeutered = true; } bool IsNeutered() const { return mNeutered; } void SetWriteOnly() { mIsWriteOnly = true; } bool IsWriteOnly() const { return mIsWriteOnly; } layers::LayersBackend GetCompositorBackendType() const { return mCompositorBackendType; } private: ~OffscreenCanvas(); nsCOMPtr<nsIGlobalObject> GetGlobalObject(); void CanvasAttrChanged() { mAttrDirty = true; ErrorResult dummy; UpdateContext(nullptr, JS::NullHandleValue, dummy); } bool mAttrDirty; bool mNeutered; bool mIsWriteOnly; uint32_t mWidth; uint32_t mHeight; layers::LayersBackend mCompositorBackendType; RefPtr<layers::CanvasClient> mCanvasClient; RefPtr<layers::AsyncCanvasRenderer> mCanvasRenderer; }; } // namespace dom } // namespace mozilla #endif // MOZILLA_DOM_OFFSCREENCANVAS_H_