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/dom/BindingDeclarations.h"
  10 #include "mozilla/layers/LayersTypes.h"
  11 #include "nsSize.h"
  12
  13 class nsICanvasRenderingContextInternal;
  14 class nsIGlobalObject;
  15
  16 namespace mozilla {
  17
  18 class ErrorResult;
  19
  20 namespace dom {
  21
  22 class BlobCallback;
  23 class EncodeCompleteCallback;
  24
  25 enum class CanvasContextType : uint8_t {
  26   NoContext,
  27   Canvas2D,
  28   OffscreenCanvas2D,
  29   WebGL1,
  30   WebGL2,
  31   WebGPU,
  32   ImageBitmap
  33 };
  34
  35 /**
  36  * Povides common RenderingContext functionality used by both OffscreenCanvas
  37  * and HTMLCanvasElement.
  38  */
  39 class CanvasRenderingContextHelper {
  40  public:
  41   CanvasRenderingContextHelper();
  42
  43   virtual bool GetOpaqueAttr() = 0;
  44
  45  protected:
  46   virtual nsresult UpdateContext(JSContext* aCx,
  47                                  JS::Handle<JS::Value> aNewContextOptions,
  48                                  ErrorResult& aRvForDictionaryInit);
  49
  50   virtual nsresult ParseParams(JSContext* aCx, const nsAString& aType,
  51                                const JS::Value& aEncoderOptions,
  52                                nsAString& outParams,
  53                                bool* const outCustomParseOptions);
  54
  55   void ToBlob(JSContext* aCx, nsIGlobalObject* global, BlobCallback& aCallback,
  56               const nsAString& aType, JS::Handle<JS::Value> aParams,
  57               bool aUsePlaceholder, ErrorResult& aRv);
  58
  59   void ToBlob(JSContext* aCx, EncodeCompleteCallback* aCallback,
  60               const nsAString& aType, JS::Handle<JS::Value> aParams,
  61               bool aUsePlaceholder, ErrorResult& aRv);
  62
  63   void ToBlob(EncodeCompleteCallback* aCallback, nsAString& aType,
  64               const nsAString& aEncodeOptions, bool aUsingCustomOptions,
  65               bool aUsePlaceholder, ErrorResult& aRv);
  66
  67   already_AddRefed<nsISupports> GetOrCreateContext(
  68       JSContext* aCx, const nsAString& aContextId,
  69       JS::Handle<JS::Value> aContextOptions, ErrorResult& aRv);
  70
  71   already_AddRefed<nsISupports> GetOrCreateContext(
  72       JSContext* aCx, CanvasContextType aContextType,
  73       JS::Handle<JS::Value> aContextOptions, ErrorResult& aRv);
  74
  75   virtual already_AddRefed<nsICanvasRenderingContextInternal> CreateContext(
  76       CanvasContextType aContextType);
  77
  78   already_AddRefed<nsICanvasRenderingContextInternal> CreateContextHelper(
  79       CanvasContextType aContextType, layers::LayersBackend aCompositorBackend);
  80
  81   virtual nsIntSize GetWidthHeight() = 0;
  82
  83   CanvasContextType mCurrentContextType;
  84   nsCOMPtr<nsICanvasRenderingContextInternal> mCurrentContext;
  85 };
  86
  87 }  // namespace dom
  88 namespace CanvasUtils {
  89 bool GetCanvasContextType(const nsAString&, dom::CanvasContextType* const);
  90 }  // namespace CanvasUtils
  91 }  // namespace mozilla
  92
  93 #endif  // MOZILLA_DOM_CANVASRENDERINGCONTEXTHELPER_H_