1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/generic/nsFontInflationData.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,75 @@
1.4 +/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +/* Per-block-formatting-context manager of font size inflation for pan and zoom UI. */
1.10 +
1.11 +#ifndef nsFontInflationData_h_
1.12 +#define nsFontInflationData_h_
1.13 +
1.14 +#include "nsIFrame.h"
1.15 +
1.16 +struct nsHTMLReflowState;
1.17 +
1.18 +class nsFontInflationData
1.19 +{
1.20 +public:
1.21 +
1.22 + static nsFontInflationData* FindFontInflationDataFor(const nsIFrame *aFrame);
1.23 +
1.24 + // Returns whether the effective width changed (which requires the
1.25 + // caller to mark its descendants dirty
1.26 + static bool
1.27 + UpdateFontInflationDataWidthFor(const nsHTMLReflowState& aReflowState);
1.28 +
1.29 + static void MarkFontInflationDataTextDirty(nsIFrame *aFrame);
1.30 +
1.31 + bool InflationEnabled() {
1.32 + if (mTextDirty) {
1.33 + ScanText();
1.34 + }
1.35 + return mInflationEnabled;
1.36 + }
1.37 +
1.38 + nscoord EffectiveWidth() const {
1.39 + return mNCAWidth;
1.40 + }
1.41 +
1.42 +private:
1.43 +
1.44 + nsFontInflationData(nsIFrame* aBFCFrame);
1.45 +
1.46 + nsFontInflationData(const nsFontInflationData&) MOZ_DELETE;
1.47 + void operator=(const nsFontInflationData&) MOZ_DELETE;
1.48 +
1.49 + void UpdateWidth(const nsHTMLReflowState &aReflowState);
1.50 + enum SearchDirection { eFromStart, eFromEnd };
1.51 + static nsIFrame* FindEdgeInflatableFrameIn(nsIFrame *aFrame,
1.52 + SearchDirection aDirection);
1.53 +
1.54 + void MarkTextDirty() { mTextDirty = true; }
1.55 + void ScanText();
1.56 + // Scan text in the subtree rooted at aFrame. Increment mTextAmount
1.57 + // by multiplying the number of characters found by the font size
1.58 + // (yielding the width that would be occupied by the characters if
1.59 + // they were all em squares). But stop scanning if mTextAmount
1.60 + // crosses mTextThreshold.
1.61 + void ScanTextIn(nsIFrame *aFrame);
1.62 +
1.63 + static const nsIFrame* FlowRootFor(const nsIFrame *aFrame)
1.64 + {
1.65 + while (!(aFrame->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT)) {
1.66 + aFrame = aFrame->GetParent();
1.67 + }
1.68 + return aFrame;
1.69 + }
1.70 +
1.71 + nsIFrame *mBFCFrame;
1.72 + nscoord mNCAWidth;
1.73 + nscoord mTextAmount, mTextThreshold;
1.74 + bool mInflationEnabled; // for this BFC
1.75 + bool mTextDirty;
1.76 +};
1.77 +
1.78 +#endif /* !defined(nsFontInflationData_h_) */
