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// Copyright 2019 Google LLC.
#ifndef Paragraph_DEFINED
#define Paragraph_DEFINED
#include "modules/skparagraph/include/FontCollection.h"
#include "modules/skparagraph/include/Metrics.h"
#include "modules/skparagraph/include/ParagraphStyle.h"
#include "modules/skparagraph/include/TextStyle.h"
class SkCanvas;
namespace skia {
namespace textlayout {
class Paragraph {
public:
Paragraph(ParagraphStyle style, sk_sp<FontCollection> fonts);
virtual ~Paragraph() = default;
SkScalar getMaxWidth() { return fWidth; }
SkScalar getHeight() { return fHeight; }
SkScalar getMinIntrinsicWidth() { return fMinIntrinsicWidth; }
SkScalar getMaxIntrinsicWidth() { return fMaxIntrinsicWidth; }
SkScalar getAlphabeticBaseline() { return fAlphabeticBaseline; }
SkScalar getIdeographicBaseline() { return fIdeographicBaseline; }
SkScalar getLongestLine() { return fLongestLine; }
bool didExceedMaxLines() { return fExceededMaxLines; }
virtual void layout(SkScalar width) = 0;
virtual void paint(SkCanvas* canvas, SkScalar x, SkScalar y) = 0;
// Returns a vector of bounding boxes that enclose all text between
// start and end glyph indexes, including start and excluding end
virtual std::vector<TextBox> getRectsForRange(unsigned start,
unsigned end,
RectHeightStyle rectHeightStyle,
RectWidthStyle rectWidthStyle) = 0;
virtual std::vector<TextBox> getRectsForPlaceholders() = 0;
// Returns the index of the glyph that corresponds to the provided coordinate,
// with the top left corner as the origin, and +y direction as down
virtual PositionWithAffinity getGlyphPositionAtCoordinate(SkScalar dx, SkScalar dy) = 0;
// Finds the first and last glyphs that define a word containing
// the glyph at index offset
virtual SkRange<size_t> getWordBoundary(unsigned offset) = 0;
virtual void getLineMetrics(std::vector<LineMetrics>&) = 0;
virtual size_t lineNumber() = 0;
virtual void markDirty() = 0;
// This function will return the number of unresolved glyphs or
// -1 if not applicable (has not been shaped yet - valid case)
virtual int32_t unresolvedGlyphs() = 0;
// Experimental API that allows fast way to update "immutable" paragraph
virtual void updateTextAlign(TextAlign textAlign) = 0;
virtual void updateText(size_t from, SkString text) = 0;
virtual void updateFontSize(size_t from, size_t to, SkScalar fontSize) = 0;
virtual void updateForegroundPaint(size_t from, size_t to, SkPaint paint) = 0;
virtual void updateBackgroundPaint(size_t from, size_t to, SkPaint paint) = 0;
enum VisitorFlags {
kWhiteSpace_VisitorFlag = 1 << 0,
};
struct VisitorInfo {
const SkFont& font;
SkPoint origin;
SkScalar advanceX;
int count;
const uint16_t* glyphs; // count values
const SkPoint* positions; // count values
const uint32_t* utf8Starts; // count+1 values
unsigned flags;
};
// lineNumber begins at 0. If info is null, this signals the end of that line.
using Visitor = std::function<void(int lineNumber, const VisitorInfo*)>;
virtual void visit(const Visitor&) = 0;
protected:
sk_sp<FontCollection> fFontCollection;
ParagraphStyle fParagraphStyle;
// Things for Flutter
SkScalar fAlphabeticBaseline;
SkScalar fIdeographicBaseline;
SkScalar fHeight;
SkScalar fWidth;
SkScalar fMaxIntrinsicWidth;
SkScalar fMinIntrinsicWidth;
SkScalar fLongestLine;
bool fExceededMaxLines;
};
} // namespace textlayout
} // namespace skia
#endif // Paragraph_DEFINED