#include <SkTextBlob.h>

Inheritance diagram for SkTextBlob:

Classes
class	Iter

Public Types
enum	GlyphPositioning : uint8_t

Public Member Functions
const SkRect &	bounds () const

uint32_t	uniqueID () const

int	getIntercepts (const SkScalar bounds[2], SkScalar intervals[], const SkPaint *paint=nullptr) const

size_t	serialize (const SkSerialProcs &procs, void *memory, size_t memory_size) const

sk_sp< SkData >	serialize (const SkSerialProcs &procs) const

Public Member Functions inherited from SkNVRefCnt< SkTextBlob >
	SkNVRefCnt ()

	~SkNVRefCnt ()

bool	unique () const

void	ref () const

void	unref () const

void	deref () const

bool	refCntGreaterThan (int32_t threadIsolatedTestCnt) const

Static Public Member Functions
static sk_sp< SkTextBlob >	MakeFromText (const void *text, size_t byteLength, const SkFont &font, SkTextEncoding encoding=SkTextEncoding::kUTF8)

static sk_sp< SkTextBlob >	MakeFromString (const char *string, const SkFont &font, SkTextEncoding encoding=SkTextEncoding::kUTF8)

static sk_sp< SkTextBlob >	MakeFromPosTextH (const void *text, size_t byteLength, const SkScalar xpos[], SkScalar constY, const SkFont &font, SkTextEncoding encoding=SkTextEncoding::kUTF8)

static sk_sp< SkTextBlob >	MakeFromPosText (const void *text, size_t byteLength, const SkPoint pos[], const SkFont &font, SkTextEncoding encoding=SkTextEncoding::kUTF8)

static sk_sp< SkTextBlob >	MakeFromRSXform (const void *text, size_t byteLength, const SkRSXform xform[], const SkFont &font, SkTextEncoding encoding=SkTextEncoding::kUTF8)

static sk_sp< SkTextBlob >	Deserialize (const void *data, size_t size, const SkDeserialProcs &procs)

Friends
class	SkNVRefCnt< SkTextBlob >

class	sktext::GlyphRunList

class	SkTextBlobBuilder

class	SkTextBlobPriv

class	SkTextBlobRunIterator

Detailed Description

SkTextBlob combines multiple text runs into an immutable container. Each text run consists of glyphs, SkPaint, and position. Only parts of SkPaint related to fonts and text rendering are used by run.

Definition at line 41 of file SkTextBlob.h.

Member Enumeration Documentation

◆ GlyphPositioning

enum SkTextBlob::GlyphPositioning : uint8_t

Definition at line 192 of file SkTextBlob.cpp.

                                : uint8_t {
    kDefault_Positioning      = 0, // Default glyph advances -- zero scalars per glyph.
    kHorizontal_Positioning   = 1, // Horizontal positioning -- one scalar per glyph.
    kFull_Positioning         = 2, // Point positioning -- two scalars per glyph.
    kRSXform_Positioning      = 3, // RSXform positioning -- four scalars per glyph.
};

Member Function Documentation

◆ bounds()

const SkRect & SkTextBlob::bounds ( ) const

inline

Returns conservative bounding box. Uses SkPaint associated with each glyph to determine glyph bounds, and unions all bounds. Returned bounds may be larger than the bounds of all glyphs in runs.

Returns: conservative bounding box

Definition at line 53 of file SkTextBlob.h.

53{ return fBounds; }

◆ Deserialize()

sk_sp< SkTextBlob > SkTextBlob::Deserialize	(	const void *	data,
		size_t	size,
		const SkDeserialProcs &	procs
	)

static

Recreates SkTextBlob that was serialized into data. Returns constructed SkTextBlob if successful; otherwise, returns nullptr. Fails if size is smaller than required data length, or if data does not permit constructing valid SkTextBlob.

procs.fTypefaceProc permits supplying a custom function to decode SkTypeface. If procs.fTypefaceProc is nullptr, default decoding is used. procs.fTypefaceCtx may be used to provide user context to procs.fTypefaceProc; procs.fTypefaceProc is called with a pointer to SkTypeface data, data byte length, and user context.

Parameters

data	pointer for serial data
size	size of data
procs	custom serial data decoders; may be nullptr

Returns: SkTextBlob constructed from data in memory

Definition at line 855 of file SkTextBlob.cpp.

                                                                        {
    SkReadBuffer buffer(data, length);
    buffer.setDeserialProcs(procs);
    return SkTextBlobPriv::MakeFromBuffer(buffer);
}

◆ getIntercepts()

int SkTextBlob::getIntercepts	(	const SkScalar	bounds[2],
		SkScalar	intervals[],
		const SkPaint *	paint = `nullptr`
	)		const

Returns the number of intervals that intersect bounds. bounds describes a pair of lines parallel to the text advance. The return count is zero or a multiple of two, and is at most twice the number of glyphs in the the blob.

Pass nullptr for intervals to determine the size of the interval array.

Runs within the blob that contain SkRSXform are ignored when computing intercepts.

Parameters

bounds	lower and upper line parallel to the advance
intervals	returned intersections; may be nullptr
paint	specifies stroking, SkPathEffect that affects the result; may be nullptr

Returns: number of intersections; may be zero

Definition at line 927 of file SkTextBlob.cpp.

                                                          {
    SkTLazy<SkPaint> defaultPaint;
    if (paint == nullptr) {
        defaultPaint.init();
        paint = defaultPaint.get();
    }
 
    sktext::GlyphRunBuilder builder;
    auto glyphRunList = builder.blobToGlyphRunList(*this, {0, 0});
 
    int intervalCount = 0;
    for (const sktext::GlyphRun& glyphRun : glyphRunList) {
        // Ignore RSXForm runs.
        if (glyphRun.scaledRotations().empty()) {
            intervalCount = get_glyph_run_intercepts(
                glyphRun, *paint, bounds, intervals, &intervalCount);
        }
    }
 
    return intervalCount;
}

◆ MakeFromPosText()

sk_sp< SkTextBlob > SkTextBlob::MakeFromPosText	(	const void *	text,
		size_t	byteLength,
		const SkPoint	pos[],
		const SkFont &	font,
		SkTextEncoding	encoding = `SkTextEncoding::kUTF8`
	)

static

Returns a textblob built from a single run of text with positions. This is equivalent to using SkTextBlobBuilder and calling allocRunPos(). Returns nullptr if byteLength is zero.

Parameters

text	character code points or glyphs drawn (based on encoding)
byteLength	byte length of text array
pos	array of positions, must contain values for all of the character points.
font	SkFont used for this run
encoding	specifies the encoding of the text array.

Returns: new textblob or nullptr

Definition at line 803 of file SkTextBlob.cpp.

                                                                       {
    const int count = font.countText(text, byteLength, encoding);
    if (count < 1) {
        return nullptr;
    }
    SkTextBlobBuilder builder;
    auto buffer = builder.allocRunPos(font, count);
    font.textToGlyphs(text, byteLength, encoding, buffer.glyphs, count);
    memcpy(buffer.points(), pos, count * sizeof(SkPoint));
    return builder.make();
}

◆ MakeFromPosTextH()

sk_sp< SkTextBlob > SkTextBlob::MakeFromPosTextH	(	const void *	text,
		size_t	byteLength,
		const SkScalar	xpos[],
		SkScalar	constY,
		const SkFont &	font,
		SkTextEncoding	encoding = `SkTextEncoding::kUTF8`
	)

static

Returns a textblob built from a single run of text with x-positions and a single y value. This is equivalent to using SkTextBlobBuilder and calling allocRunPosH(). Returns nullptr if byteLength is zero.

Parameters

text	character code points or glyphs drawn (based on encoding)
byteLength	byte length of text array
xpos	array of x-positions, must contain values for all of the character points.
constY	shared y-position for each character point, to be paired with each xpos.
font	SkFont used for this run
encoding	specifies the encoding of the text array.

Returns: new textblob or nullptr

Definition at line 817 of file SkTextBlob.cpp.

                                                                                            {
    const int count = font.countText(text, byteLength, encoding);
    if (count < 1) {
        return nullptr;
    }
    SkTextBlobBuilder builder;
    auto buffer = builder.allocRunPosH(font, count, constY);
    font.textToGlyphs(text, byteLength, encoding, buffer.glyphs, count);
    memcpy(buffer.pos, xpos, count * sizeof(SkScalar));
    return builder.make();
}

◆ MakeFromRSXform()

sk_sp< SkTextBlob > SkTextBlob::MakeFromRSXform	(	const void *	text,
		size_t	byteLength,
		const SkRSXform	xform[],
		const SkFont &	font,
		SkTextEncoding	encoding = `SkTextEncoding::kUTF8`
	)

static

Definition at line 831 of file SkTextBlob.cpp.

                                                                       {
    const int count = font.countText(text, byteLength, encoding);
    if (count < 1) {
        return nullptr;
    }
    SkTextBlobBuilder builder;
    auto buffer = builder.allocRunRSXform(font, count);
    font.textToGlyphs(text, byteLength, encoding, buffer.glyphs, count);
    memcpy(buffer.xforms(), xform, count * sizeof(SkRSXform));
    return builder.make();
}

◆ MakeFromString()

static sk_sp< SkTextBlob > SkTextBlob::MakeFromString	(	const char *	string,
		const SkFont &	font,
		SkTextEncoding	encoding = `SkTextEncoding::kUTF8`
	)

inlinestatic

Creates SkTextBlob with a single run. string meaning depends on SkTextEncoding; by default, string is encoded as UTF-8.

font contains attributes used to define the run text.

When encoding is SkTextEncoding::kUTF8, SkTextEncoding::kUTF16, or SkTextEncoding::kUTF32, this function uses the default character-to-glyph mapping from the SkTypeface in font. It does not perform typeface fallback for characters not found in the SkTypeface. It does not perform kerning or other complex shaping; glyphs are positioned based on their default advances.

Parameters

string	character code points or glyphs drawn
font	text size, typeface, text scale, and so on, used to draw
encoding	text encoding used in the text array

Returns: SkTextBlob constructed from one run

Definition at line 115 of file SkTextBlob.h.

                                                                                           {
        if (!string) {
            return nullptr;
        }
        return MakeFromText(string, strlen(string), font, encoding);
    }

◆ MakeFromText()

sk_sp< SkTextBlob > SkTextBlob::MakeFromText	(	const void *	text,
		size_t	byteLength,
		const SkFont &	font,
		SkTextEncoding	encoding = `SkTextEncoding::kUTF8`
	)

static

Creates SkTextBlob with a single run.

font contains attributes used to define the run text.

When encoding is SkTextEncoding::kUTF8, SkTextEncoding::kUTF16, or SkTextEncoding::kUTF32, this function uses the default character-to-glyph mapping from the SkTypeface in font. It does not perform typeface fallback for characters not found in the SkTypeface. It does not perform kerning or other complex shaping; glyphs are positioned based on their default advances.

Parameters

text	character code points or glyphs drawn
byteLength	byte length of text array
font	text size, typeface, text scale, and so on, used to draw
encoding	text encoding used in the text array

Returns: SkTextBlob constructed from one run

Definition at line 788 of file SkTextBlob.cpp.

                                                                    {
    // Note: we deliberately promote this to fully positioned blobs, since we'd have to pay the
    // same cost down stream (i.e. computing bounds), so its cheaper to pay the cost once now.
    const int count = font.countText(text, byteLength, encoding);
    if (count < 1) {
        return nullptr;
    }
    SkTextBlobBuilder builder;
    auto buffer = builder.allocRunPos(font, count);
    font.textToGlyphs(text, byteLength, encoding, buffer.glyphs, count);
    font.getPos(buffer.glyphs, count, buffer.points(), {0, 0});
    return builder.make();
}

◆ serialize() [1/2]

sk_sp< SkData > SkTextBlob::serialize ( const SkSerialProcs & procs ) const

Returns storage containing SkData describing SkTextBlob, using optional custom encoders.

procs.fTypefaceProc permits supplying a custom function to encode SkTypeface. If procs.fTypefaceProc is nullptr, default encoding is used. procs.fTypefaceCtx may be used to provide user context to procs.fTypefaceProc; procs.fTypefaceProc is called with a pointer to SkTypeface and user context.

Parameters

procs custom serial data encoders; may be nullptr

Returns: storage containing serialized SkTextBlob

example: https://fiddle.skia.org/c/@TextBlob_serialize_2

Definition at line 845 of file SkTextBlob.cpp.

                                                                    {
    SkBinaryWriteBuffer buffer(procs);
    SkTextBlobPriv::Flatten(*this, buffer);
 
    size_t total = buffer.bytesWritten();
    sk_sp<SkData> data = SkData::MakeUninitialized(total);
    buffer.writeToMemory(data->writable_data());
    return data;
}

◆ serialize() [2/2]

size_t SkTextBlob::serialize	(	const SkSerialProcs &	procs,
		void *	memory,
		size_t	memory_size
	)		const

Writes data to allow later reconstruction of SkTextBlob. memory points to storage to receive the encoded data, and memory_size describes the size of storage. Returns bytes used if provided storage is large enough to hold all data; otherwise, returns zero.

procs.fTypefaceProc permits supplying a custom function to encode SkTypeface. If procs.fTypefaceProc is nullptr, default encoding is used. procs.fTypefaceCtx may be used to provide user context to procs.fTypefaceProc; procs.fTypefaceProc is called with a pointer to SkTypeface and user context.

Parameters

procs	custom serial data encoders; may be nullptr
memory	storage for data
memory_size	size of storage

Returns: bytes written, or zero if required storage is larger than memory_size

example: https://fiddle.skia.org/c/@TextBlob_serialize

Definition at line 864 of file SkTextBlob.cpp.

                                                                                               {
    SkBinaryWriteBuffer buffer(memory, memory_size, procs);
    SkTextBlobPriv::Flatten(*this, buffer);
    return buffer.usingInitialStorage() ? buffer.bytesWritten() : 0u;
}

◆ uniqueID()

uint32_t SkTextBlob::uniqueID ( ) const

inline

Returns a non-zero value unique among all text blobs.

Returns: identifier for SkTextBlob

Definition at line 59 of file SkTextBlob.h.

59{ return fUniqueID; }

Friends And Related Symbol Documentation

◆ SkNVRefCnt< SkTextBlob >

friend class SkNVRefCnt< SkTextBlob >

friend

Definition at line 209 of file SkTextBlob.h.

◆ sktext::GlyphRunList

friend class sktext::GlyphRunList

friend

Definition at line 269 of file SkTextBlob.h.

◆ SkTextBlobBuilder

friend class SkTextBlobBuilder

friend

Definition at line 270 of file SkTextBlob.h.

◆ SkTextBlobPriv

friend class SkTextBlobPriv

friend

Definition at line 271 of file SkTextBlob.h.

◆ SkTextBlobRunIterator

friend class SkTextBlobRunIterator

friend

Definition at line 272 of file SkTextBlob.h.

The documentation for this class was generated from the following files:

third_party/skia/include/core/SkTextBlob.h
third_party/skia/src/core/SkTextBlob.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

Member Enumeration Documentation

◆ GlyphPositioning

Member Function Documentation

◆ bounds()

◆ Deserialize()

◆ getIntercepts()

◆ MakeFromPosText()

◆ MakeFromPosTextH()

◆ MakeFromRSXform()

◆ MakeFromString()

◆ MakeFromText()

◆ serialize() [1/2]

◆ serialize() [2/2]

◆ uniqueID()

Friends And Related Symbol Documentation

◆ SkNVRefCnt< SkTextBlob >

◆ sktext::GlyphRunList

◆ SkTextBlobBuilder

◆ SkTextBlobPriv

◆ SkTextBlobRunIterator