layout/generic/nsCanvasFrame.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
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /* rendering object that goes directly inside the document's scrollbars */
   7
   8 #ifndef nsCanvasFrame_h___
   9 #define nsCanvasFrame_h___
  10
  11 #include "mozilla/Attributes.h"
  12 #include "mozilla/EventForwards.h"
  13 #include "nsContainerFrame.h"
  14 #include "nsIScrollPositionListener.h"
  15 #include "nsDisplayList.h"
  16 #include "nsIAnonymousContentCreator.h"
  17 #include "nsIDOMEventListener.h"
  18
  19 class nsPresContext;
  20 class nsRenderingContext;
  21
  22 /**
  23  * Root frame class.
  24  *
  25  * The root frame is the parent frame for the document element's frame.
  26  * It only supports having a single child frame which must be an area
  27  * frame
  28  */
  29 class nsCanvasFrame MOZ_FINAL : public nsContainerFrame,
  30                                 public nsIScrollPositionListener,
  31                                 public nsIAnonymousContentCreator
  32 {
  33 public:
  34   explicit nsCanvasFrame(nsStyleContext* aContext)
  35   : nsContainerFrame(aContext),
  36     mDoPaintFocus(false),
  37     mAddedScrollPositionListener(false) {}
  38
  39   NS_DECL_QUERYFRAME_TARGET(nsCanvasFrame)
  40   NS_DECL_QUERYFRAME
  41   NS_DECL_FRAMEARENA_HELPERS
  42
  43
  44   virtual void DestroyFrom(nsIFrame* aDestructRoot) MOZ_OVERRIDE;
  45
  46   virtual mozilla::WritingMode GetWritingMode() const MOZ_OVERRIDE
  47   {
  48     nsIContent* rootElem = GetContent();
  49     if (rootElem) {
  50       nsIFrame* rootElemFrame = rootElem->GetPrimaryFrame();
  51       if (rootElemFrame) {
  52         return rootElemFrame->GetWritingMode();
  53       }
  54     }
  55     return nsIFrame::GetWritingMode();
  56   }
  57
  58 #ifdef DEBUG
  59   virtual void SetInitialChildList(ChildListID     aListID,
  60                                    nsFrameList&    aChildList) MOZ_OVERRIDE;
  61   virtual void AppendFrames(ChildListID     aListID,
  62                             nsFrameList&    aFrameList) MOZ_OVERRIDE;
  63   virtual void InsertFrames(ChildListID     aListID,
  64                             nsIFrame*       aPrevFrame,
  65                             nsFrameList&    aFrameList) MOZ_OVERRIDE;
  66   virtual void RemoveFrame(ChildListID     aListID,
  67                            nsIFrame*       aOldFrame) MOZ_OVERRIDE;
  68 #endif
  69
  70   virtual nscoord GetMinISize(nsRenderingContext *aRenderingContext) MOZ_OVERRIDE;
  71   virtual nscoord GetPrefISize(nsRenderingContext *aRenderingContext) MOZ_OVERRIDE;
  72   virtual void Reflow(nsPresContext*           aPresContext,
  73                       nsHTMLReflowMetrics&     aDesiredSize,
  74                       const nsHTMLReflowState& aReflowState,
  75                       nsReflowStatus&          aStatus) MOZ_OVERRIDE;
  76   virtual bool IsFrameOfType(uint32_t aFlags) const MOZ_OVERRIDE
  77   {
  78     return nsContainerFrame::IsFrameOfType(aFlags &
  79              ~(nsIFrame::eCanContainOverflowContainers));
  80   }
  81
  82   // nsIAnonymousContentCreator
  83   virtual nsresult CreateAnonymousContent(nsTArray<ContentInfo>& aElements) MOZ_OVERRIDE;
  84   virtual void AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements, uint32_t aFilter) MOZ_OVERRIDE;
  85
  86   // Touch caret handle function
  87   mozilla::dom::Element* GetTouchCaretElement() const
  88   {
  89      return mTouchCaretElement;
  90   }
  91
  92   // Selection Caret Handle function
  93   mozilla::dom::Element* GetSelectionCaretsStartElement() const
  94   {
  95     return mSelectionCaretsStartElement;
  96   }
  97
  98   mozilla::dom::Element* GetSelectionCaretsEndElement() const
  99   {
 100     return mSelectionCaretsEndElement;
 101   }
 102
 103   mozilla::dom::Element* GetCustomContentContainer() const
 104   {
 105     return mCustomContentContainer;
 106   }
 107
 108   /** SetHasFocus tells the CanvasFrame to draw with focus ring
 109    *  @param aHasFocus true to show focus ring, false to hide it
 110    */
 111   NS_IMETHOD SetHasFocus(bool aHasFocus);
 112
 113   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
 114                                 const nsRect&           aDirtyRect,
 115                                 const nsDisplayListSet& aLists) MOZ_OVERRIDE;
 116
 117   void PaintFocus(nsRenderingContext& aRenderingContext, nsPoint aPt);
 118
 119   // nsIScrollPositionListener
 120   virtual void ScrollPositionWillChange(nscoord aX, nscoord aY) MOZ_OVERRIDE;
 121   virtual void ScrollPositionDidChange(nscoord aX, nscoord aY) MOZ_OVERRIDE {}
 122
 123   /**
 124    * Get the "type" of the frame
 125    *
 126    * @see nsGkAtoms::canvasFrame
 127    */
 128   virtual nsIAtom* GetType() const MOZ_OVERRIDE;
 129
 130   virtual nsresult StealFrame(nsIFrame* aChild, bool aForceNormal) MOZ_OVERRIDE
 131   {
 132     NS_ASSERTION(!aForceNormal, "No-one should be passing this in here");
 133
 134     // nsCanvasFrame keeps overflow container continuations of its child
 135     // frame in main child list
 136     nsresult rv = nsContainerFrame::StealFrame(aChild, true);
 137     if (NS_FAILED(rv)) {
 138       rv = nsContainerFrame::StealFrame(aChild);
 139     }
 140     return rv;
 141   }
 142
 143 #ifdef DEBUG_FRAME_DUMP
 144   virtual nsresult GetFrameName(nsAString& aResult) const MOZ_OVERRIDE;
 145 #endif
 146   virtual nsresult GetContentForEvent(mozilla::WidgetEvent* aEvent,
 147                                       nsIContent** aContent) MOZ_OVERRIDE;
 148
 149   nsRect CanvasArea() const;
 150
 151 protected:
 152   // Data members
 153   bool                      mDoPaintFocus;
 154   bool                      mAddedScrollPositionListener;
 155
 156   nsCOMPtr<mozilla::dom::Element> mTouchCaretElement;
 157   nsCOMPtr<mozilla::dom::Element> mSelectionCaretsStartElement;
 158   nsCOMPtr<mozilla::dom::Element> mSelectionCaretsEndElement;
 159   nsCOMPtr<mozilla::dom::Element> mCustomContentContainer;
 160
 161   class DummyTouchListener MOZ_FINAL : public nsIDOMEventListener
 162   {
 163   public:
 164     NS_DECL_ISUPPORTS
 165
 166     NS_IMETHOD HandleEvent(nsIDOMEvent* aEvent) MOZ_OVERRIDE
 167     {
 168       return NS_OK;
 169     }
 170   private:
 171     ~DummyTouchListener() {}
 172   };
 173
 174   /**
 175    * A no-op touch-listener used for APZ purposes.
 176    */
 177   nsRefPtr<DummyTouchListener> mDummyTouchListener;
 178 };
 179
 180 /**
 181  * Override nsDisplayBackground methods so that we pass aBGClipRect to
 182  * PaintBackground, covering the whole overflow area.
 183  * We can also paint an "extra background color" behind the normal
 184  * background.
 185  */
 186 class nsDisplayCanvasBackgroundColor : public nsDisplayItem {
 187 public:
 188   nsDisplayCanvasBackgroundColor(nsDisplayListBuilder* aBuilder, nsIFrame *aFrame)
 189     : nsDisplayItem(aBuilder, aFrame)
 190     , mColor(NS_RGBA(0,0,0,0))
 191   {
 192   }
 193
 194   virtual bool ComputeVisibility(nsDisplayListBuilder* aBuilder,
 195                                  nsRegion* aVisibleRegion) MOZ_OVERRIDE
 196   {
 197     return NS_GET_A(mColor) > 0;
 198   }
 199   virtual nsRegion GetOpaqueRegion(nsDisplayListBuilder* aBuilder,
 200                                    bool* aSnap) MOZ_OVERRIDE
 201   {
 202     if (NS_GET_A(mColor) == 255) {
 203       return nsRegion(GetBounds(aBuilder, aSnap));
 204     }
 205     return nsRegion();
 206   }
 207   virtual bool IsUniform(nsDisplayListBuilder* aBuilder, nscolor* aColor) MOZ_OVERRIDE
 208   {
 209     *aColor = mColor;
 210     return true;
 211   }
 212   virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder, bool* aSnap) MOZ_OVERRIDE
 213   {
 214     nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
 215     *aSnap = true;
 216     return frame->CanvasArea() + ToReferenceFrame();
 217   }
 218   virtual void HitTest(nsDisplayListBuilder* aBuilder, const nsRect& aRect,
 219                        HitTestState* aState, nsTArray<nsIFrame*> *aOutFrames) MOZ_OVERRIDE
 220   {
 221     // We need to override so we don't consider border-radius.
 222     aOutFrames->AppendElement(mFrame);
 223   }
 224
 225   virtual nsDisplayItemGeometry* AllocateGeometry(nsDisplayListBuilder* aBuilder) MOZ_OVERRIDE
 226   {
 227     return new nsDisplayItemBoundsGeometry(this, aBuilder);
 228   }
 229
 230   virtual void ComputeInvalidationRegion(nsDisplayListBuilder* aBuilder,
 231                                          const nsDisplayItemGeometry* aGeometry,
 232                                          nsRegion* aInvalidRegion) MOZ_OVERRIDE
 233   {
 234     const nsDisplayItemBoundsGeometry* geometry = static_cast<const nsDisplayItemBoundsGeometry*>(aGeometry);
 235     ComputeInvalidationRegionDifference(aBuilder, geometry, aInvalidRegion);
 236   }
 237
 238   virtual void Paint(nsDisplayListBuilder* aBuilder,
 239                      nsRenderingContext* aCtx) MOZ_OVERRIDE;
 240
 241   void SetExtraBackgroundColor(nscolor aColor)
 242   {
 243     mColor = aColor;
 244   }
 245
 246   NS_DISPLAY_DECL_NAME("CanvasBackgroundColor", TYPE_CANVAS_BACKGROUND_COLOR)
 247 #ifdef MOZ_DUMP_PAINTING
 248   virtual void WriteDebugInfo(std::stringstream& aStream) MOZ_OVERRIDE;
 249 #endif
 250
 251 private:
 252   nscolor mColor;
 253 };
 254
 255 class nsDisplayCanvasBackgroundImage : public nsDisplayBackgroundImage {
 256 public:
 257   nsDisplayCanvasBackgroundImage(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
 258                                  uint32_t aLayer, const nsStyleBackground* aBg)
 259     : nsDisplayBackgroundImage(aBuilder, aFrame, aLayer, aBg)
 260   {}
 261
 262   virtual void Paint(nsDisplayListBuilder* aBuilder, nsRenderingContext* aCtx) MOZ_OVERRIDE;
 263
 264   virtual void NotifyRenderingChanged() MOZ_OVERRIDE
 265   {
 266     mFrame->Properties().Delete(nsIFrame::CachedBackgroundImage());
 267     mFrame->Properties().Delete(nsIFrame::CachedBackgroundImageDT());
 268   }
 269
 270   virtual bool ShouldFixToViewport(LayerManager* aManager) MOZ_OVERRIDE
 271   {
 272     // Put background-attachment:fixed canvas background images in their own
 273     // compositing layer. Since we know their background painting area can't
 274     // change (unless the viewport size itself changes), async scrolling
 275     // will work well.
 276     return mBackgroundStyle->mLayers[mLayer].mAttachment == NS_STYLE_BG_ATTACHMENT_FIXED &&
 277            !mBackgroundStyle->mLayers[mLayer].mImage.IsEmpty();
 278   }
 279
 280   // We still need to paint a background color as well as an image for this item,
 281   // so we can't support this yet.
 282   virtual bool SupportsOptimizingToImage() MOZ_OVERRIDE { return false; }
 283
 284
 285   NS_DISPLAY_DECL_NAME("CanvasBackgroundImage", TYPE_CANVAS_BACKGROUND_IMAGE)
 286 };
 287
 288 class nsDisplayCanvasThemedBackground : public nsDisplayThemedBackground {
 289 public:
 290   nsDisplayCanvasThemedBackground(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame)
 291     : nsDisplayThemedBackground(aBuilder, aFrame)
 292   {}
 293
 294   virtual void Paint(nsDisplayListBuilder* aBuilder, nsRenderingContext* aCtx) MOZ_OVERRIDE;
 295
 296   NS_DISPLAY_DECL_NAME("CanvasThemedBackground", TYPE_CANVAS_THEMED_BACKGROUND)
 297 };
 298
 299 #endif /* nsCanvasFrame_h___ */