blob: c78b0798412a1e0256e08c6fdf01330a3ce37265 [file] [log] [blame]
// 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 ParagraphPainter;
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;
virtual void paint(ParagraphPainter* painter, 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 some of "immutable" paragraph attributes
// but not the text itself
virtual void updateTextAlign(TextAlign textAlign) = 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;
// Editing API
virtual int getLineNumberAt(TextIndex codeUnitIndex) const = 0;
/* Returns line metrics info for the line
*
* @param lineNumber a line number
* @param lineMetrics an address to return the info (in case of null just skipped)
* @return true if the line is found; false if not
*/
virtual bool getLineMetricsAt(int lineNumber, LineMetrics* lineMetrics) const = 0;
/* Returns the visible text on the line (excluding a possible ellipsis)
*
* @param lineNumber a line number
* @param includeSpaces indicates if the whitespaces should be included
* @return the range of the text that is shown in the line
*/
virtual TextRange getActualTextRange(int lineNumber, bool includeSpaces) const = 0;
struct GlyphClusterInfo {
SkRect fBounds;
TextRange fClusterTextRange;
TextDirection fGlyphClusterPosition;
};
/** Finds a glyph cluster for text index
*
* @param codeUnitIndex a text index
* @param glyphInfo a glyph cluster info filled if not null
* @return true if glyph cluster was found; false if not
*/
virtual bool getGlyphClusterAt(TextIndex codeUnitIndex, GlyphClusterInfo* glyphInfo) = 0;
/** Finds the closest glyph cluster for a visual text position
*
* @param dx x coordinate
* @param dy y coordinate
* @param glyphInfo a glyph cluster info filled if not null
* @return
*/
virtual bool getClosestGlyphClusterAt(SkScalar dx,
SkScalar dy,
GlyphClusterInfo* glyphInfo) = 0;
struct FontInfo {
FontInfo(const SkFont font, const TextRange textRange)
: fFont(font), fTextRange(textRange) { }
virtual ~FontInfo() = default;
FontInfo(const FontInfo& ) = default;
SkFont fFont;
TextRange fTextRange;
};
/** Returns the font that is used to shape the text at the position
*
* @param codeUnitIndex text index
* @return font info or an empty font info if the text is not found
*/
virtual SkFont getFontAt(TextIndex codeUnitIndex) const = 0;
/** Returns the information about all the fonts used to shape the paragraph text
*
* @return a list of fonts and text ranges
*/
virtual std::vector<FontInfo> getFonts() const = 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