diff options
Diffstat (limited to 'include/minikin/MeasuredText.h')
| -rw-r--r-- | include/minikin/MeasuredText.h | 114 |
1 files changed, 100 insertions, 14 deletions
diff --git a/include/minikin/MeasuredText.h b/include/minikin/MeasuredText.h index fa37eb6..a3b8bf1 100644 --- a/include/minikin/MeasuredText.h +++ b/include/minikin/MeasuredText.h @@ -31,6 +31,27 @@ namespace minikin { +// Structs that of line metrics information. +struct LineMetrics { + LineMetrics() : advance(0) {} + LineMetrics(const MinikinExtent& extent, const MinikinRect& bounds, float advance) + : extent(extent), bounds(bounds), advance(advance) {} + + void append(const LineMetrics& metrics) { + append(metrics.extent, metrics.bounds, metrics.advance); + } + + void append(const MinikinExtent& nextExtent, const MinikinRect& nextBounds, float nextAdvance) { + extent.extendBy(nextExtent); + bounds.join(nextBounds, advance, 0); + advance += nextAdvance; + } + + MinikinExtent extent; + MinikinRect bounds; + float advance; +}; + class Run { public: Run(const Range& range) : mRange(range) {} @@ -42,6 +63,9 @@ public: // Returns true if this run can be broken into multiple pieces for line breaking. virtual bool canBreak() const = 0; + // Returns true if this run can be hyphenated. + virtual bool canHyphenate() const = 0; + // Return the line break style(lb) for this run. virtual LineBreakStyle lineBreakStyle() const = 0; @@ -53,13 +77,17 @@ public: // Fills the each character's advances, extents and overhangs. virtual void getMetrics(const U16StringPiece& text, std::vector<float>* advances, - LayoutPieces* precomputed, LayoutPieces* outPieces) const = 0; + std::vector<uint8_t>* flags, LayoutPieces* precomputed, + bool boundsCalculation, LayoutPieces* outPieces) const = 0; virtual std::pair<float, MinikinRect> getBounds(const U16StringPiece& text, const Range& range, const LayoutPieces& pieces) const = 0; virtual MinikinExtent getExtent(const U16StringPiece& text, const Range& range, const LayoutPieces& pieces) const = 0; + virtual LineMetrics getLineMetrics(const U16StringPiece& text, const Range& range, + const LayoutPieces& pieces) const = 0; + virtual void appendLayout(const U16StringPiece& text, const Range& range, const Range& contextRange, const LayoutPieces& pieces, const MinikinPaint& paint, uint32_t outOrigin, @@ -93,11 +121,12 @@ protected: class StyleRun : public Run { public: StyleRun(const Range& range, MinikinPaint&& paint, int lineBreakStyle, int lineBreakWordStyle, - bool isRtl) + bool hyphenation, bool isRtl) : Run(range), mPaint(std::move(paint)), mLineBreakStyle(lineBreakStyle), mLineBreakWordStyle(lineBreakWordStyle), + mHyphenation(hyphenation), mIsRtl(isRtl) {} bool canBreak() const override { return true; } @@ -107,11 +136,13 @@ public: LineBreakWordStyle lineBreakWordStyle() const override { return static_cast<LineBreakWordStyle>(mLineBreakWordStyle); } + bool canHyphenate() const override { return mHyphenation; } uint32_t getLocaleListId() const override { return mPaint.localeListId; } bool isRtl() const override { return mIsRtl; } void getMetrics(const U16StringPiece& text, std::vector<float>* advances, - LayoutPieces* precomputed, LayoutPieces* outPieces) const override; + std::vector<uint8_t>* flags, LayoutPieces* precomputed, bool boundsCalculation, + LayoutPieces* outPieces) const override; std::pair<float, MinikinRect> getBounds(const U16StringPiece& text, const Range& range, const LayoutPieces& pieces) const override; @@ -119,6 +150,9 @@ public: MinikinExtent getExtent(const U16StringPiece& text, const Range& range, const LayoutPieces& pieces) const override; + LineMetrics getLineMetrics(const U16StringPiece& text, const Range& range, + const LayoutPieces& pieces) const override; + void appendLayout(const U16StringPiece& text, const Range& range, const Range& contextRange, const LayoutPieces& pieces, const MinikinPaint& paint, uint32_t outOrigin, StartHyphenEdit startHyphen, EndHyphenEdit endHyphen, @@ -135,6 +169,7 @@ private: MinikinPaint mPaint; int mLineBreakStyle; int mLineBreakWordStyle; + const bool mHyphenation; const bool mIsRtl; }; @@ -145,12 +180,14 @@ public: bool isRtl() const { return false; } bool canBreak() const { return false; } + bool canHyphenate() const { return false; } LineBreakStyle lineBreakStyle() const override { return LineBreakStyle::None; } LineBreakWordStyle lineBreakWordStyle() const override { return LineBreakWordStyle::None; } uint32_t getLocaleListId() const { return mLocaleListId; } void getMetrics(const U16StringPiece& /* text */, std::vector<float>* advances, - LayoutPieces* /* precomputed */, LayoutPieces* /* outPieces */) const override { + std::vector<uint8_t>* /*flags*/, LayoutPieces* /* precomputed */, bool, + LayoutPieces* /* outPieces */) const override { (*advances)[mRange.getStart()] = mWidth; // TODO: Get the extents information from the caller. } @@ -167,6 +204,11 @@ public: return MinikinExtent(); } + LineMetrics getLineMetrics(const U16StringPiece& /*text*/, const Range& /*range*/, + const LayoutPieces& /*pieces*/) const override { + return LineMetrics(); + } + void appendLayout(const U16StringPiece& /* text */, const Range& /* range */, const Range& /* contextRange */, const LayoutPieces& /* pieces */, const MinikinPaint& /* paint */, uint32_t /* outOrigin */, @@ -209,10 +251,45 @@ public: // The style information. std::vector<std::unique_ptr<Run>> runs; + // Per character flags. + // The loweset bit represents that that character *may* have overhang. If this bit is not set, + // the character doesn't have overhang. If this bit is set, the character *may* have overhang. + // This information is used for determining using the bounding box based line breaking. + static constexpr uint8_t MAY_OVERHANG_BIT = 0b0000'0001; + std::vector<uint8_t> flags; + // The copied layout pieces for construcing final layouts. // TODO: Stop assigning width/extents if layout pieces are available for reducing memory impact. LayoutPieces layoutPieces; + bool hasOverhang(const Range& range) const { + // Heuristics: Check first 5 and last 5 characters and treat there is overhang if at least + // one character has overhang. + constexpr uint32_t CHARS_TO_DUMPER = 5; + + if (range.getLength() < CHARS_TO_DUMPER * 2) { + for (uint32_t i : range) { + if ((flags[i] & MAY_OVERHANG_BIT) == MAY_OVERHANG_BIT) { + return true; + } + } + } else { + Range first = Range(range.getStart(), range.getStart() + CHARS_TO_DUMPER); + Range last = Range(range.getEnd() - CHARS_TO_DUMPER, range.getEnd()); + for (uint32_t i : first) { + if ((flags[i] & MAY_OVERHANG_BIT) == MAY_OVERHANG_BIT) { + return true; + } + } + for (uint32_t i : last) { + if ((flags[i] & MAY_OVERHANG_BIT) == MAY_OVERHANG_BIT) { + return true; + } + } + } + return false; + } + uint32_t getMemoryUsage() const { return sizeof(float) * widths.size() + sizeof(HyphenBreak) * hyphenBreaks.size() + layoutPieces.getMemoryUsage(); @@ -223,6 +300,7 @@ public: EndHyphenEdit endHyphen); MinikinRect getBounds(const U16StringPiece& textBuf, const Range& range) const; MinikinExtent getExtent(const U16StringPiece& textBuf, const Range& range) const; + LineMetrics getLineMetrics(const U16StringPiece& textBuf, const Range& range) const; MeasuredText(MeasuredText&&) = default; MeasuredText& operator=(MeasuredText&&) = default; @@ -233,14 +311,15 @@ private: friend class MeasuredTextBuilder; void measure(const U16StringPiece& textBuf, bool computeHyphenation, bool computeLayout, - bool ignoreHyphenKerning, MeasuredText* hint); + bool computeBounds, bool ignoreHyphenKerning, MeasuredText* hint); // Use MeasuredTextBuilder instead. MeasuredText(const U16StringPiece& textBuf, std::vector<std::unique_ptr<Run>>&& runs, - bool computeHyphenation, bool computeLayout, bool ignoreHyphenKerning, - MeasuredText* hint) - : widths(textBuf.size()), runs(std::move(runs)) { - measure(textBuf, computeHyphenation, computeLayout, ignoreHyphenKerning, hint); + bool computeHyphenation, bool computeLayout, bool computeBounds, + bool ignoreHyphenKerning, MeasuredText* hint) + : widths(textBuf.size()), runs(std::move(runs)), flags(textBuf.size(), 0) { + measure(textBuf, computeHyphenation, computeLayout, computeBounds, ignoreHyphenKerning, + hint); } }; @@ -249,9 +328,10 @@ public: MeasuredTextBuilder() {} void addStyleRun(int32_t start, int32_t end, MinikinPaint&& paint, int lineBreakStyle, - int lineBreakWordStyle, bool isRtl) { + int lineBreakWordStyle, bool hyphenation, bool isRtl) { mRuns.emplace_back(std::make_unique<StyleRun>(Range(start, end), std::move(paint), - lineBreakStyle, lineBreakWordStyle, isRtl)); + lineBreakStyle, lineBreakWordStyle, + hyphenation, isRtl)); } void addReplacementRun(int32_t start, int32_t end, float width, uint32_t localeListId) { @@ -267,10 +347,16 @@ public: std::unique_ptr<MeasuredText> build(const U16StringPiece& textBuf, bool computeHyphenation, bool computeLayout, bool ignoreHyphenKerning, MeasuredText* hint) { + return build(textBuf, computeHyphenation, computeLayout, false, ignoreHyphenKerning, hint); + } + + std::unique_ptr<MeasuredText> build(const U16StringPiece& textBuf, bool computeHyphenation, + bool computeLayout, bool computeBounds, + bool ignoreHyphenKerning, MeasuredText* hint) { // Unable to use make_unique here since make_unique is not a friend of MeasuredText. - return std::unique_ptr<MeasuredText>(new MeasuredText(textBuf, std::move(mRuns), - computeHyphenation, computeLayout, - ignoreHyphenKerning, hint)); + return std::unique_ptr<MeasuredText>( + new MeasuredText(textBuf, std::move(mRuns), computeHyphenation, computeLayout, + computeBounds, ignoreHyphenKerning, hint)); } MINIKIN_PREVENT_COPY_ASSIGN_AND_MOVE(MeasuredTextBuilder); |