dom/canvas/OffscreenCanvasDisplayHelper.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef MOZILLA_DOM_OFFSCREENCANVASDISPLAYHELPER_H_
   8 #define MOZILLA_DOM_OFFSCREENCANVASDISPLAYHELPER_H_
   9
  10 #include "ImageContainer.h"
  11 #include "GLContextTypes.h"
  12 #include "mozilla/dom/CanvasRenderingContextHelper.h"
  13 #include "mozilla/gfx/Point.h"
  14 #include "mozilla/layers/LayersTypes.h"
  15 #include "mozilla/Maybe.h"
  16 #include "mozilla/Mutex.h"
  17 #include "mozilla/RefPtr.h"
  18 #include "mozilla/UniquePtr.h"
  19 #include "nsISupportsImpl.h"
  20 #include "nsThreadUtils.h"
  21
  22 namespace mozilla::dom {
  23 class HTMLCanvasElement;
  24 class OffscreenCanvas;
  25 class ThreadSafeWorkerRef;
  26
  27 struct OffscreenCanvasDisplayData final {
  28   mozilla::gfx::IntSize mSize = {0, 0};
  29   bool mDoPaintCallbacks = false;
  30   bool mIsOpaque = true;
  31   bool mIsAlphaPremult = true;
  32   mozilla::gl::OriginPos mOriginPos = gl::OriginPos::TopLeft;
  33   Maybe<layers::RemoteTextureOwnerId> mOwnerId;
  34 };
  35
  36 class OffscreenCanvasDisplayHelper final {
  37   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(OffscreenCanvasDisplayHelper)
  38
  39  public:
  40   explicit OffscreenCanvasDisplayHelper(HTMLCanvasElement* aCanvasElement,
  41                                         uint32_t aWidth, uint32_t aHeight);
  42
  43   CanvasContextType GetContextType() const;
  44
  45   RefPtr<layers::ImageContainer> GetImageContainer() const;
  46
  47   void UpdateContext(OffscreenCanvas* aOffscreenCanvas,
  48                      RefPtr<ThreadSafeWorkerRef>&& aWorkerRef,
  49                      CanvasContextType aType, const Maybe<int32_t>& aChildId);
  50
  51   void FlushForDisplay();
  52
  53   bool CommitFrameToCompositor(nsICanvasRenderingContextInternal* aContext,
  54                                layers::TextureType aTextureType,
  55                                const Maybe<OffscreenCanvasDisplayData>& aData);
  56
  57   void DestroyCanvas();
  58   void DestroyElement();
  59
  60   already_AddRefed<mozilla::gfx::SourceSurface> GetSurfaceSnapshot();
  61   already_AddRefed<mozilla::layers::Image> GetAsImage();
  62   UniquePtr<uint8_t[]> GetImageBuffer(int32_t* aOutFormat,
  63                                       gfx::IntSize* aOutImageSize);
  64
  65  private:
  66   ~OffscreenCanvasDisplayHelper();
  67   void MaybeQueueInvalidateElement() MOZ_REQUIRES(mMutex);
  68   void InvalidateElement();
  69
  70   already_AddRefed<gfx::SourceSurface> TransformSurface(
  71       gfx::SourceSurface* aSurface, bool aHasAlpha, bool aIsAlphaPremult,
  72       gl::OriginPos aOriginPos) const;
  73
  74   mutable Mutex mMutex;
  75   HTMLCanvasElement* MOZ_NON_OWNING_REF mCanvasElement MOZ_GUARDED_BY(mMutex);
  76   OffscreenCanvas* MOZ_NON_OWNING_REF mOffscreenCanvas MOZ_GUARDED_BY(mMutex) =
  77       nullptr;
  78   RefPtr<layers::ImageContainer> mImageContainer MOZ_GUARDED_BY(mMutex);
  79   RefPtr<gfx::SourceSurface> mFrontBufferSurface MOZ_GUARDED_BY(mMutex);
  80   RefPtr<ThreadSafeWorkerRef> mWorkerRef MOZ_GUARDED_BY(mMutex);
  81
  82   OffscreenCanvasDisplayData mData MOZ_GUARDED_BY(mMutex);
  83   CanvasContextType mType MOZ_GUARDED_BY(mMutex) = CanvasContextType::NoContext;
  84   Maybe<uint32_t> mContextManagerId MOZ_GUARDED_BY(mMutex);
  85   Maybe<int32_t> mContextChildId MOZ_GUARDED_BY(mMutex);
  86   const mozilla::layers::ImageContainer::ProducerID mImageProducerID;
  87   mozilla::layers::ImageContainer::FrameID mLastFrameID MOZ_GUARDED_BY(mMutex) =
  88       0;
  89   bool mPendingInvalidate MOZ_GUARDED_BY(mMutex) = false;
  90 };
  91
  92 }  // namespace mozilla::dom
  93
  94 #endif  // MOZILLA_DOM_OFFSCREENCANVASDISPLAYHELPER_H_