dom/canvas/CanvasRenderingContextHelper.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   4  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef MOZILLA_DOM_CANVASRENDERINGCONTEXTHELPER_H_
   7 #define MOZILLA_DOM_CANVASRENDERINGCONTEXTHELPER_H_
   8
   9 #include "mozilla/UniquePtr.h"
  10 #include "mozilla/dom/BindingDeclarations.h"
  11 #include "mozilla/gfx/Point.h"
  12 #include "mozilla/layers/LayersTypes.h"
  13 #include "nsSize.h"
  14
  15 class nsICanvasRenderingContextInternal;
  16 class nsIGlobalObject;
  17
  18 namespace mozilla {
  19
  20 class ErrorResult;
  21
  22 namespace dom {
  23
  24 class BlobCallback;
  25 class EncodeCompleteCallback;
  26
  27 enum class CanvasContextType : uint8_t {
  28   NoContext,
  29   Canvas2D,
  30   OffscreenCanvas2D,
  31   WebGL1,
  32   WebGL2,
  33   WebGPU,
  34   ImageBitmap
  35 };
  36
  37 /**
  38  * Povides common RenderingContext functionality used by both OffscreenCanvas
  39  * and HTMLCanvasElement.
  40  */
  41 class CanvasRenderingContextHelper {
  42  public:
  43   CanvasRenderingContextHelper();
  44
  45   virtual bool GetOpaqueAttr() = 0;
  46
  47  protected:
  48   virtual nsresult UpdateContext(JSContext* aCx,
  49                                  JS::Handle<JS::Value> aNewContextOptions,
  50                                  ErrorResult& aRvForDictionaryInit);
  51
  52   virtual nsresult ParseParams(JSContext* aCx, const nsAString& aType,
  53                                const JS::Value& aEncoderOptions,
  54                                nsAString& outParams,
  55                                bool* const outCustomParseOptions);
  56
  57   void ToBlob(JSContext* aCx, nsIGlobalObject* global, BlobCallback& aCallback,
  58               const nsAString& aType, JS::Handle<JS::Value> aParams,
  59               bool aUsePlaceholder, ErrorResult& aRv);
  60
  61   void ToBlob(JSContext* aCx, EncodeCompleteCallback* aCallback,
  62               const nsAString& aType, JS::Handle<JS::Value> aParams,
  63               bool aUsePlaceholder, ErrorResult& aRv);
  64
  65   void ToBlob(EncodeCompleteCallback* aCallback, nsAString& aType,
  66               const nsAString& aEncodeOptions, bool aUsingCustomOptions,
  67               bool aUsePlaceholder, ErrorResult& aRv);
  68
  69   virtual UniquePtr<uint8_t[]> GetImageBuffer(int32_t* aOutFormat,
  70                                               gfx::IntSize* aOutImageSize);
  71
  72   already_AddRefed<nsISupports> GetOrCreateContext(
  73       JSContext* aCx, const nsAString& aContextId,
  74       JS::Handle<JS::Value> aContextOptions, ErrorResult& aRv);
  75
  76   already_AddRefed<nsISupports> GetOrCreateContext(
  77       JSContext* aCx, CanvasContextType aContextType,
  78       JS::Handle<JS::Value> aContextOptions, ErrorResult& aRv);
  79
  80   virtual already_AddRefed<nsICanvasRenderingContextInternal> CreateContext(
  81       CanvasContextType aContextType);
  82
  83   already_AddRefed<nsICanvasRenderingContextInternal> CreateContextHelper(
  84       CanvasContextType aContextType, layers::LayersBackend aCompositorBackend);
  85
  86   virtual nsIntSize GetWidthHeight() = 0;
  87
  88   CanvasContextType mCurrentContextType;
  89   nsCOMPtr<nsICanvasRenderingContextInternal> mCurrentContext;
  90 };
  91
  92 }  // namespace dom
  93 namespace CanvasUtils {
  94 bool GetCanvasContextType(const nsAString&, dom::CanvasContextType* const);
  95 }  // namespace CanvasUtils
  96 }  // namespace mozilla
  97
  98 #endif  // MOZILLA_DOM_CANVASRENDERINGCONTEXTHELPER_H_