The Tor Browser: layout/generic/nsFontInflationData.h@b8a032363ba2

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

     1 /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */

     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/. */

     6 /* Per-block-formatting-context manager of font size inflation for pan and zoom UI. */

     8 #ifndef nsFontInflationData_h_

     9 #define nsFontInflationData_h_

    11 #include "nsIFrame.h"

    13 struct nsHTMLReflowState;

    15 class nsFontInflationData

    16 {

    17 public:

    19   static nsFontInflationData* FindFontInflationDataFor(const nsIFrame *aFrame);

    21   // Returns whether the effective width changed (which requires the

    22   // caller to mark its descendants dirty

    23   static bool

    24     UpdateFontInflationDataWidthFor(const nsHTMLReflowState& aReflowState);

    26   static void MarkFontInflationDataTextDirty(nsIFrame *aFrame);

    28   bool InflationEnabled() {

    29     if (mTextDirty) {

    30       ScanText();

    31     }

    32     return mInflationEnabled;

    33   }

    35   nscoord EffectiveWidth() const {

    36     return mNCAWidth;

    37   }

    39 private:

    41   nsFontInflationData(nsIFrame* aBFCFrame);

    43   nsFontInflationData(const nsFontInflationData&) MOZ_DELETE;

    44   void operator=(const nsFontInflationData&) MOZ_DELETE;

    46   void UpdateWidth(const nsHTMLReflowState &aReflowState);

    47   enum SearchDirection { eFromStart, eFromEnd };

    48   static nsIFrame* FindEdgeInflatableFrameIn(nsIFrame *aFrame,

    49                                              SearchDirection aDirection);

    51   void MarkTextDirty() { mTextDirty = true; }

    52   void ScanText();

    53   // Scan text in the subtree rooted at aFrame.  Increment mTextAmount

    54   // by multiplying the number of characters found by the font size

    55   // (yielding the width that would be occupied by the characters if

    56   // they were all em squares).  But stop scanning if mTextAmount

    57   // crosses mTextThreshold.

    58   void ScanTextIn(nsIFrame *aFrame);

    60   static const nsIFrame* FlowRootFor(const nsIFrame *aFrame)

    61   {

    62     while (!(aFrame->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT)) {

    63       aFrame = aFrame->GetParent();

    64     }

    65     return aFrame;

    66   }

    68   nsIFrame *mBFCFrame;

    69   nscoord mNCAWidth;

    70   nscoord mTextAmount, mTextThreshold;

    71   bool mInflationEnabled; // for this BFC

    72   bool mTextDirty;

    73 };

    75 #endif /* !defined(nsFontInflationData_h_) */

The Tor Browser / file revision