blob: 8831ce03ebfa9bf1fb84fe75124afcfcdb36c89c [file] [log] [blame]
/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "include/core/SkBBHFactory.h"
#include "include/core/SkBitmap.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkData.h"
#include "include/core/SkDrawable.h"
#include "include/core/SkFontMetrics.h"
#include "include/core/SkGraphics.h"
#include "include/core/SkPath.h"
#include "include/core/SkPictureRecorder.h"
#include "include/core/SkStream.h"
#include "include/core/SkString.h"
#include "include/private/SkColorData.h"
#include "include/private/SkMalloc.h"
#include "include/private/SkMutex.h"
#include "include/private/SkTPin.h"
#include "include/private/SkTemplates.h"
#include "include/private/SkTo.h"
#include "src/core/SkAdvancedTypefaceMetrics.h"
#include "src/core/SkDescriptor.h"
#include "src/core/SkFDot6.h"
#include "src/core/SkFontDescriptor.h"
#include "src/core/SkGlyph.h"
#include "src/core/SkMask.h"
#include "src/core/SkMaskGamma.h"
#include "src/core/SkScalerContext.h"
#include "src/core/SkTSearch.h"
#include "src/ports/SkFontHost_FreeType_common.h"
#include "src/sfnt/SkOTUtils.h"
#include "src/sfnt/SkSFNTHeader.h"
#include "src/sfnt/SkTTCFHeader.h"
#include "src/utils/SkCallableTraits.h"
#include "src/utils/SkMatrix22.h"
#include <memory>
#include <optional>
#include <tuple>
#include <ft2build.h>
#include <freetype/ftadvanc.h>
#include <freetype/ftimage.h>
#include <freetype/ftbitmap.h>
#ifdef FT_COLOR_H // 2.10.0
# include <freetype/ftcolor.h>
#endif
#include <freetype/freetype.h>
#include <freetype/ftlcdfil.h>
#include <freetype/ftmodapi.h>
#include <freetype/ftmm.h>
#include <freetype/ftoutln.h>
#include <freetype/ftsizes.h>
#include <freetype/ftsystem.h>
#include <freetype/tttables.h>
#include <freetype/t1tables.h>
#include <freetype/ftfntfmt.h>
namespace {
[[maybe_unused]] static inline const constexpr bool kSkShowTextBlitCoverage = false;
}
// SK_FREETYPE_MINIMUM_RUNTIME_VERSION 0x<major><minor><patch><flags>
// Flag SK_FREETYPE_DLOPEN: also try dlopen to get newer features.
#define SK_FREETYPE_DLOPEN (0x1)
#ifndef SK_FREETYPE_MINIMUM_RUNTIME_VERSION
# if defined(SK_BUILD_FOR_ANDROID_FRAMEWORK) || defined (SK_BUILD_FOR_GOOGLE3)
# define SK_FREETYPE_MINIMUM_RUNTIME_VERSION (((FREETYPE_MAJOR) << 24) | ((FREETYPE_MINOR) << 16) | ((FREETYPE_PATCH) << 8))
# else
# define SK_FREETYPE_MINIMUM_RUNTIME_VERSION ((2 << 24) | (8 << 16) | (1 << 8) | (SK_FREETYPE_DLOPEN))
# endif
#endif
#if SK_FREETYPE_MINIMUM_RUNTIME_VERSION & SK_FREETYPE_DLOPEN
# include <dlfcn.h>
#endif
#ifdef TT_SUPPORT_COLRV1
// FT_ClipBox and FT_Get_Color_Glyph_ClipBox introduced VER-2-11-0-18-g47cf8ebf4
// FT_COLR_COMPOSITE_PLUS and renumbering introduced VER-2-11-0-21-ge40ae7569
// FT_SIZEOF_LONG_LONG introduced VER-2-11-0-31-gffdac8d67
// FT_PaintRadialGradient changed size and layout at VER-2-11-0-147-gd3d3ff76d
// FT_STATIC_CAST introduced VER-2-11-0-172-g9079c5d91
// So undefine TT_SUPPORT_COLRV1 before 2.11.1 but not if FT_STATIC_CAST is defined.
#if (((FREETYPE_MAJOR) < 2) || \
((FREETYPE_MAJOR) == 2 && (FREETYPE_MINOR) < 11) || \
((FREETYPE_MAJOR) == 2 && (FREETYPE_MINOR) == 11 && (FREETYPE_PATCH) < 1)) && \
!defined(FT_STATIC_CAST)
# undef TT_SUPPORT_COLRV1
#endif
#endif
//#define ENABLE_GLYPH_SPEW // for tracing calls
//#define DUMP_STRIKE_CREATION
//#define SK_FONTHOST_FREETYPE_RUNTIME_VERSION
//#define SK_GAMMA_APPLY_TO_A8
#if 1
#define LOG_INFO(...)
#else
#define LOG_INFO SkDEBUGF
#endif
static bool isLCD(const SkScalerContextRec& rec) {
return SkMask::kLCD16_Format == rec.fMaskFormat;
}
static SkScalar SkFT_FixedToScalar(FT_Fixed x) {
return SkFixedToScalar(x);
}
using SkUniqueFTFace =
std::unique_ptr<FT_FaceRec, SkFunctionWrapper<decltype(FT_Done_Face), FT_Done_Face>>;
//////////////////////////////////////////////////////////////////////////
using FT_Alloc_size_t = SkCallableTraits<FT_Alloc_Func>::argument<1>::type;
static_assert(std::is_same<FT_Alloc_size_t, long >::value ||
std::is_same<FT_Alloc_size_t, size_t>::value,"");
extern "C" {
static void* sk_ft_alloc(FT_Memory, FT_Alloc_size_t size) {
return sk_malloc_canfail(size);
}
static void sk_ft_free(FT_Memory, void* block) {
sk_free(block);
}
static void* sk_ft_realloc(FT_Memory, FT_Alloc_size_t cur_size,
FT_Alloc_size_t new_size, void* block) {
return sk_realloc_throw(block, new_size);
}
}
FT_MemoryRec_ gFTMemory = { nullptr, sk_ft_alloc, sk_ft_free, sk_ft_realloc };
class FreeTypeLibrary : SkNoncopyable {
public:
FreeTypeLibrary() : fLibrary(nullptr) {
if (FT_New_Library(&gFTMemory, &fLibrary)) {
return;
}
FT_Add_Default_Modules(fLibrary);
FT_Set_Default_Properties(fLibrary);
#ifdef TT_SUPPORT_COLRV1
if (SkGraphics::GetVariableColrV1Enabled()) {
FT_Bool variableColrV1Enabled = true;
FT_Property_Set(
fLibrary, "truetype", "TEMPORARY-enable-variable-colrv1", &variableColrV1Enabled);
}
#endif
// Subpixel anti-aliasing may be unfiltered until the LCD filter is set.
// Newer versions may still need this, so this test with side effects must come first.
// The default has changed over time, so this doesn't mean the same thing to all users.
FT_Library_SetLcdFilter(fLibrary, FT_LCD_FILTER_DEFAULT);
}
~FreeTypeLibrary() {
if (fLibrary) {
FT_Done_Library(fLibrary);
}
}
FT_Library library() { return fLibrary; }
private:
FT_Library fLibrary;
// FT_Library_SetLcdFilterWeights 2.4.0
// FT_LOAD_COLOR 2.5.0
// FT_Pixel_Mode::FT_PIXEL_MODE_BGRA 2.5.0
// Thread safety in 2.6.0
// freetype/ftfntfmt.h (rename) 2.6.0
// Direct header inclusion 2.6.1
// FT_Get_Var_Design_Coordinates 2.7.1
// FT_LOAD_BITMAP_METRICS_ONLY 2.7.1
// FT_Set_Default_Properties 2.7.2
// The 'light' hinting is vertical only from 2.8.0
// FT_Get_Var_Axis_Flags 2.8.1
// FT_VAR_AXIS_FLAG_HIDDEN was introduced in FreeType 2.8.1
// --------------------
// FT_Done_MM_Var 2.9.0 (Currenty setting ft_free to a known allocator.)
// freetype/ftcolor.h 2.10.0 (Currently assuming if compiled with FT_COLOR_H runtime available.)
// Ubuntu 18.04 2.8.1
// Debian 10 2.9.1
// openSUSE Leap 15.2 2.10.1
// Fedora 32 2.10.4
// RHEL 8 2.9.1
};
static SkMutex& f_t_mutex() {
static SkMutex& mutex = *(new SkMutex);
return mutex;
}
static FreeTypeLibrary* gFTLibrary;
///////////////////////////////////////////////////////////////////////////
class SkTypeface_FreeType::FaceRec {
public:
SkUniqueFTFace fFace;
FT_StreamRec fFTStream;
std::unique_ptr<SkStreamAsset> fSkStream;
FT_UShort fFTPaletteEntryCount = 0;
std::unique_ptr<SkColor[]> fSkPalette;
static std::unique_ptr<FaceRec> Make(const SkTypeface_FreeType* typeface);
~FaceRec();
private:
FaceRec(std::unique_ptr<SkStreamAsset> stream);
void setupAxes(const SkFontData& data);
void setupPalette(const SkFontData& data);
// Private to ref_ft_library and unref_ft_library
static int gFTCount;
// Caller must lock f_t_mutex() before calling this function.
static bool ref_ft_library() {
f_t_mutex().assertHeld();
SkASSERT(gFTCount >= 0);
if (0 == gFTCount) {
SkASSERT(nullptr == gFTLibrary);
gFTLibrary = new FreeTypeLibrary;
}
++gFTCount;
return gFTLibrary->library();
}
// Caller must lock f_t_mutex() before calling this function.
static void unref_ft_library() {
f_t_mutex().assertHeld();
SkASSERT(gFTCount > 0);
--gFTCount;
if (0 == gFTCount) {
SkASSERT(nullptr != gFTLibrary);
delete gFTLibrary;
SkDEBUGCODE(gFTLibrary = nullptr;)
}
}
};
int SkTypeface_FreeType::FaceRec::gFTCount;
extern "C" {
static unsigned long sk_ft_stream_io(FT_Stream ftStream,
unsigned long offset,
unsigned char* buffer,
unsigned long count)
{
SkStreamAsset* stream = static_cast<SkStreamAsset*>(ftStream->descriptor.pointer);
if (count) {
if (!stream->seek(offset)) {
return 0;
}
count = stream->read(buffer, count);
}
return count;
}
static void sk_ft_stream_close(FT_Stream) {}
}
SkTypeface_FreeType::FaceRec::FaceRec(std::unique_ptr<SkStreamAsset> stream)
: fSkStream(std::move(stream))
{
sk_bzero(&fFTStream, sizeof(fFTStream));
fFTStream.size = fSkStream->getLength();
fFTStream.descriptor.pointer = fSkStream.get();
fFTStream.read = sk_ft_stream_io;
fFTStream.close = sk_ft_stream_close;
f_t_mutex().assertHeld();
ref_ft_library();
}
SkTypeface_FreeType::FaceRec::~FaceRec() {
f_t_mutex().assertHeld();
fFace.reset(); // Must release face before the library, the library frees existing faces.
unref_ft_library();
}
void SkTypeface_FreeType::FaceRec::setupAxes(const SkFontData& data) {
if (!(fFace->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS)) {
return;
}
// If a named variation is requested, don't overwrite the named variation's position.
if (data.getIndex() > 0xFFFF) {
return;
}
SkDEBUGCODE(
FT_MM_Var* variations = nullptr;
if (FT_Get_MM_Var(fFace.get(), &variations)) {
LOG_INFO("INFO: font %s claims variations, but none found.\n",
rec->fFace->family_name);
return;
}
SkAutoFree autoFreeVariations(variations);
if (static_cast<FT_UInt>(data.getAxisCount()) != variations->num_axis) {
LOG_INFO("INFO: font %s has %d variations, but %d were specified.\n",
rec->fFace->family_name, variations->num_axis, data.getAxisCount());
return;
}
)
SkAutoSTMalloc<4, FT_Fixed> coords(data.getAxisCount());
for (int i = 0; i < data.getAxisCount(); ++i) {
coords[i] = data.getAxis()[i];
}
if (FT_Set_Var_Design_Coordinates(fFace.get(), data.getAxisCount(), coords.get())) {
LOG_INFO("INFO: font %s has variations, but specified variations could not be set.\n",
rec->fFace->family_name);
return;
}
}
void SkTypeface_FreeType::FaceRec::setupPalette(const SkFontData& data) {
#ifdef FT_COLOR_H
FT_Palette_Data paletteData;
if (FT_Palette_Data_Get(fFace.get(), &paletteData)) {
return;
}
// Treat out of range values as 0. Still apply overrides.
// https://www.w3.org/TR/css-fonts-4/#base-palette-desc
FT_UShort basePaletteIndex = 0;
if (SkTFitsIn<FT_UShort>(data.getPaletteIndex()) &&
SkTo<FT_UShort>(data.getPaletteIndex()) < paletteData.num_palettes)
{
basePaletteIndex = data.getPaletteIndex();
}
FT_Color* ftPalette = nullptr;
if (FT_Palette_Select(fFace.get(), basePaletteIndex, &ftPalette)) {
return;
}
fFTPaletteEntryCount = paletteData.num_palette_entries;
for (int i = 0; i < data.getPaletteOverrideCount(); ++i) {
const SkFontArguments::Palette::Override& paletteOverride = data.getPaletteOverrides()[i];
if (0 <= paletteOverride.index && paletteOverride.index < fFTPaletteEntryCount) {
const SkColor& skColor = paletteOverride.color;
FT_Color& ftColor = ftPalette[paletteOverride.index];
ftColor.blue = SkColorGetB(skColor);
ftColor.green = SkColorGetG(skColor);
ftColor.red = SkColorGetR(skColor);
ftColor.alpha = SkColorGetA(skColor);
}
}
fSkPalette.reset(new SkColor[fFTPaletteEntryCount]);
for (int i = 0; i < fFTPaletteEntryCount; ++i) {
fSkPalette[i] = SkColorSetARGB(ftPalette[i].alpha,
ftPalette[i].red,
ftPalette[i].green,
ftPalette[i].blue);
}
#endif
}
// Will return nullptr on failure
// Caller must lock f_t_mutex() before calling this function.
std::unique_ptr<SkTypeface_FreeType::FaceRec>
SkTypeface_FreeType::FaceRec::Make(const SkTypeface_FreeType* typeface) {
f_t_mutex().assertHeld();
std::unique_ptr<SkFontData> data = typeface->makeFontData();
if (nullptr == data || !data->hasStream()) {
return nullptr;
}
std::unique_ptr<FaceRec> rec(new FaceRec(data->detachStream()));
FT_Open_Args args;
memset(&args, 0, sizeof(args));
const void* memoryBase = rec->fSkStream->getMemoryBase();
if (memoryBase) {
args.flags = FT_OPEN_MEMORY;
args.memory_base = (const FT_Byte*)memoryBase;
args.memory_size = rec->fSkStream->getLength();
} else {
args.flags = FT_OPEN_STREAM;
args.stream = &rec->fFTStream;
}
{
FT_Face rawFace;
FT_Error err = FT_Open_Face(gFTLibrary->library(), &args, data->getIndex(), &rawFace);
if (err) {
SK_TRACEFTR(err, "unable to open font '%x'", typeface->uniqueID());
return nullptr;
}
rec->fFace.reset(rawFace);
}
SkASSERT(rec->fFace);
rec->setupAxes(*data);
rec->setupPalette(*data);
// FreeType will set the charmap to the "most unicode" cmap if it exists.
// If there are no unicode cmaps, the charmap is set to nullptr.
// However, "symbol" cmaps should also be considered "fallback unicode" cmaps
// because they are effectively private use area only (even if they aren't).
// This is the last on the fallback list at
// https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6cmap.html
if (!rec->fFace->charmap) {
FT_Select_Charmap(rec->fFace.get(), FT_ENCODING_MS_SYMBOL);
}
return rec;
}
class AutoFTAccess {
public:
AutoFTAccess(const SkTypeface_FreeType* tf) : fFaceRec(nullptr) {
f_t_mutex().acquire();
fFaceRec = tf->getFaceRec();
}
~AutoFTAccess() {
f_t_mutex().release();
}
FT_Face face() { return fFaceRec ? fFaceRec->fFace.get() : nullptr; }
private:
SkTypeface_FreeType::FaceRec* fFaceRec;
};
///////////////////////////////////////////////////////////////////////////
class SkScalerContext_FreeType : public SkScalerContext_FreeType_Base {
public:
SkScalerContext_FreeType(sk_sp<SkTypeface_FreeType>,
const SkScalerContextEffects&,
const SkDescriptor* desc);
~SkScalerContext_FreeType() override;
bool success() const {
return fFTSize != nullptr && fFace != nullptr;
}
protected:
bool generateAdvance(SkGlyph* glyph) override;
void generateMetrics(SkGlyph* glyph, SkArenaAlloc*) override;
void generateImage(const SkGlyph& glyph) override;
bool generatePath(const SkGlyph& glyph, SkPath* path) override;
sk_sp<SkDrawable> generateDrawable(const SkGlyph&) override;
void generateFontMetrics(SkFontMetrics*) override;
private:
SkTypeface_FreeType::FaceRec* fFaceRec; // Borrowed face from the typeface's FaceRec.
FT_Face fFace; // Borrowed face from fFaceRec.
FT_Size fFTSize; // The size to apply to the fFace.
FT_Int fStrikeIndex; // The bitmap strike for the fFace (or -1 if none).
/** The rest of the matrix after FreeType handles the size.
* With outline font rasterization this is handled by FreeType with FT_Set_Transform.
* With bitmap only fonts this matrix must be applied to scale the bitmap.
*/
SkMatrix fMatrix22Scalar;
/** Same as fMatrix22Scalar, but in FreeType units and space. */
FT_Matrix fMatrix22;
/** The actual size requested. */
SkVector fScale;
uint32_t fLoadGlyphFlags;
bool fDoLinearMetrics;
bool fLCDIsVert;
FT_Error setupSize();
static bool getBoundsOfCurrentOutlineGlyph(FT_GlyphSlot glyph, SkRect* bounds);
static void setGlyphBounds(SkGlyph* glyph, SkRect* bounds, bool subpixel);
bool getCBoxForLetter(char letter, FT_BBox* bbox);
// Caller must lock f_t_mutex() before calling this function.
void updateGlyphBoundsIfLCD(SkGlyph* glyph);
// Caller must lock f_t_mutex() before calling this function.
// update FreeType2 glyph slot with glyph emboldened
void emboldenIfNeeded(FT_Face face, FT_GlyphSlot glyph, SkGlyphID gid);
bool shouldSubpixelBitmap(const SkGlyph&, const SkMatrix&);
};
///////////////////////////////////////////////////////////////////////////
static bool canEmbed(FT_Face face) {
FT_UShort fsType = FT_Get_FSType_Flags(face);
return (fsType & (FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING |
FT_FSTYPE_BITMAP_EMBEDDING_ONLY)) == 0;
}
static bool canSubset(FT_Face face) {
FT_UShort fsType = FT_Get_FSType_Flags(face);
return (fsType & FT_FSTYPE_NO_SUBSETTING) == 0;
}
static SkAdvancedTypefaceMetrics::FontType get_font_type(FT_Face face) {
const char* fontType = FT_Get_X11_Font_Format(face);
static struct { const char* s; SkAdvancedTypefaceMetrics::FontType t; } values[] = {
{ "Type 1", SkAdvancedTypefaceMetrics::kType1_Font },
{ "CID Type 1", SkAdvancedTypefaceMetrics::kType1CID_Font },
{ "CFF", SkAdvancedTypefaceMetrics::kCFF_Font },
{ "TrueType", SkAdvancedTypefaceMetrics::kTrueType_Font },
};
for(const auto& v : values) { if (strcmp(fontType, v.s) == 0) { return v.t; } }
return SkAdvancedTypefaceMetrics::kOther_Font;
}
static bool is_opentype_font_data_standard_format(const SkTypeface& typeface) {
// FreeType reports TrueType for any data that can be decoded to TrueType or OpenType.
// However, there are alternate data formats for OpenType, like wOFF and wOF2.
std::unique_ptr<SkStreamAsset> stream = typeface.openStream(nullptr);
if (!stream) {
return false;
}
char buffer[4];
if (stream->read(buffer, 4) < 4) {
return false;
}
SkFourByteTag tag = SkSetFourByteTag(buffer[0], buffer[1], buffer[2], buffer[3]);
SK_OT_ULONG otTag = SkEndian_SwapBE32(tag);
return otTag == SkSFNTHeader::fontType_WindowsTrueType::TAG ||
otTag == SkSFNTHeader::fontType_MacTrueType::TAG ||
otTag == SkSFNTHeader::fontType_PostScript::TAG ||
otTag == SkSFNTHeader::fontType_OpenTypeCFF::TAG ||
otTag == SkTTCFHeader::TAG;
}
std::unique_ptr<SkAdvancedTypefaceMetrics> SkTypeface_FreeType::onGetAdvancedMetrics() const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return nullptr;
}
std::unique_ptr<SkAdvancedTypefaceMetrics> info(new SkAdvancedTypefaceMetrics);
info->fPostScriptName.set(FT_Get_Postscript_Name(face));
info->fFontName = info->fPostScriptName;
if (FT_HAS_MULTIPLE_MASTERS(face)) {
info->fFlags |= SkAdvancedTypefaceMetrics::kVariable_FontFlag;
}
if (!canEmbed(face)) {
info->fFlags |= SkAdvancedTypefaceMetrics::kNotEmbeddable_FontFlag;
}
if (!canSubset(face)) {
info->fFlags |= SkAdvancedTypefaceMetrics::kNotSubsettable_FontFlag;
}
info->fType = get_font_type(face);
if (info->fType == SkAdvancedTypefaceMetrics::kTrueType_Font &&
!is_opentype_font_data_standard_format(*this))
{
info->fFlags |= SkAdvancedTypefaceMetrics::kAltDataFormat_FontFlag;
}
info->fStyle = (SkAdvancedTypefaceMetrics::StyleFlags)0;
if (FT_IS_FIXED_WIDTH(face)) {
info->fStyle |= SkAdvancedTypefaceMetrics::kFixedPitch_Style;
}
if (face->style_flags & FT_STYLE_FLAG_ITALIC) {
info->fStyle |= SkAdvancedTypefaceMetrics::kItalic_Style;
}
PS_FontInfoRec psFontInfo;
TT_Postscript* postTable;
if (FT_Get_PS_Font_Info(face, &psFontInfo) == 0) {
info->fItalicAngle = psFontInfo.italic_angle;
} else if ((postTable = (TT_Postscript*)FT_Get_Sfnt_Table(face, ft_sfnt_post)) != nullptr) {
info->fItalicAngle = SkFixedFloorToInt(postTable->italicAngle);
} else {
info->fItalicAngle = 0;
}
info->fAscent = face->ascender;
info->fDescent = face->descender;
TT_PCLT* pcltTable;
TT_OS2* os2Table;
if ((pcltTable = (TT_PCLT*)FT_Get_Sfnt_Table(face, ft_sfnt_pclt)) != nullptr) {
info->fCapHeight = pcltTable->CapHeight;
uint8_t serif_style = pcltTable->SerifStyle & 0x3F;
if (2 <= serif_style && serif_style <= 6) {
info->fStyle |= SkAdvancedTypefaceMetrics::kSerif_Style;
} else if (9 <= serif_style && serif_style <= 12) {
info->fStyle |= SkAdvancedTypefaceMetrics::kScript_Style;
}
} else if (((os2Table = (TT_OS2*)FT_Get_Sfnt_Table(face, ft_sfnt_os2)) != nullptr) &&
// sCapHeight is available only when version 2 or later.
os2Table->version != 0xFFFF &&
os2Table->version >= 2)
{
info->fCapHeight = os2Table->sCapHeight;
}
info->fBBox = SkIRect::MakeLTRB(face->bbox.xMin, face->bbox.yMax,
face->bbox.xMax, face->bbox.yMin);
return info;
}
void SkTypeface_FreeType::getGlyphToUnicodeMap(SkUnichar* dstArray) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return;
}
FT_Long numGlyphs = face->num_glyphs;
if (!dstArray) { SkASSERT(numGlyphs == 0); }
sk_bzero(dstArray, sizeof(SkUnichar) * numGlyphs);
FT_UInt glyphIndex;
SkUnichar charCode = FT_Get_First_Char(face, &glyphIndex);
while (glyphIndex) {
SkASSERT(glyphIndex < SkToUInt(numGlyphs));
// Use the first character that maps to this glyphID. https://crbug.com/359065
if (0 == dstArray[glyphIndex]) {
dstArray[glyphIndex] = charCode;
}
charCode = FT_Get_Next_Char(face, charCode, &glyphIndex);
}
}
void SkTypeface_FreeType::getPostScriptGlyphNames(SkString* dstArray) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return;
}
FT_Long numGlyphs = face->num_glyphs;
if (!dstArray) { SkASSERT(numGlyphs == 0); }
if (FT_HAS_GLYPH_NAMES(face)) {
for (int gID = 0; gID < numGlyphs; ++gID) {
char glyphName[128]; // PS limit for names is 127 bytes.
FT_Get_Glyph_Name(face, gID, glyphName, 128);
dstArray[gID] = glyphName;
}
}
}
bool SkTypeface_FreeType::onGetPostScriptName(SkString* skPostScriptName) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return false;
}
const char* ftPostScriptName = FT_Get_Postscript_Name(face);
if (!ftPostScriptName) {
return false;
}
if (skPostScriptName) {
*skPostScriptName = ftPostScriptName;
}
return true;
}
///////////////////////////////////////////////////////////////////////////
static bool bothZero(SkScalar a, SkScalar b) {
return 0 == a && 0 == b;
}
// returns false if there is any non-90-rotation or skew
static bool isAxisAligned(const SkScalerContextRec& rec) {
return 0 == rec.fPreSkewX &&
(bothZero(rec.fPost2x2[0][1], rec.fPost2x2[1][0]) ||
bothZero(rec.fPost2x2[0][0], rec.fPost2x2[1][1]));
}
std::unique_ptr<SkScalerContext> SkTypeface_FreeType::onCreateScalerContext(
const SkScalerContextEffects& effects, const SkDescriptor* desc) const
{
auto c = std::make_unique<SkScalerContext_FreeType>(
sk_ref_sp(const_cast<SkTypeface_FreeType*>(this)), effects, desc);
if (c->success()) {
return std::move(c);
}
return SkScalerContext::MakeEmpty(
sk_ref_sp(const_cast<SkTypeface_FreeType*>(this)), effects, desc);
}
/** Copy the design variation coordinates into 'coordinates'.
*
* @param coordinates the buffer into which to write the design variation coordinates.
* @param coordinateCount the number of entries available through 'coordinates'.
*
* @return The number of axes, or -1 if there is an error.
* If 'coordinates != nullptr' and 'coordinateCount >= numAxes' then 'coordinates' will be
* filled with the variation coordinates describing the position of this typeface in design
* variation space. It is possible the number of axes can be retrieved but actual position
* cannot.
*/
static int GetVariationDesignPosition(AutoFTAccess& fta,
SkFontArguments::VariationPosition::Coordinate coordinates[], int coordinateCount)
{
FT_Face face = fta.face();
if (!face) {
return -1;
}
if (!(face->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS)) {
return 0;
}
FT_MM_Var* variations = nullptr;
if (FT_Get_MM_Var(face, &variations)) {
return -1;
}
SkAutoFree autoFreeVariations(variations);
if (!coordinates || coordinateCount < SkToInt(variations->num_axis)) {
return variations->num_axis;
}
SkAutoSTMalloc<4, FT_Fixed> coords(variations->num_axis);
if (FT_Get_Var_Design_Coordinates(face, variations->num_axis, coords.get())) {
return -1;
}
for (FT_UInt i = 0; i < variations->num_axis; ++i) {
coordinates[i].axis = variations->axis[i].tag;
coordinates[i].value = SkFixedToScalar(coords[i]);
}
return variations->num_axis;
}
std::unique_ptr<SkFontData> SkTypeface_FreeType::cloneFontData(const SkFontArguments& args) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return nullptr;
}
Scanner::AxisDefinitions axisDefinitions;
if (!Scanner::GetAxes(face, &axisDefinitions)) {
return nullptr;
}
int axisCount = axisDefinitions.size();
SkAutoSTMalloc<4, SkFontArguments::VariationPosition::Coordinate> currentPosition(axisCount);
int currentAxisCount = GetVariationDesignPosition(fta, currentPosition, axisCount);
SkString name;
SkAutoSTMalloc<4, SkFixed> axisValues(axisCount);
Scanner::computeAxisValues(axisDefinitions, args.getVariationDesignPosition(), axisValues, name,
currentAxisCount == axisCount ? currentPosition.get() : nullptr);
int ttcIndex;
std::unique_ptr<SkStreamAsset> stream = this->openStream(&ttcIndex);
return std::make_unique<SkFontData>(std::move(stream),
ttcIndex,
args.getPalette().index,
axisValues.get(),
axisCount,
args.getPalette().overrides,
args.getPalette().overrideCount);
}
void SkTypeface_FreeType::onFilterRec(SkScalerContextRec* rec) const {
//BOGUS: http://code.google.com/p/chromium/issues/detail?id=121119
//Cap the requested size as larger sizes give bogus values.
//Remove when http://code.google.com/p/skia/issues/detail?id=554 is fixed.
//Note that this also currently only protects against large text size requests,
//the total matrix is not taken into account here.
if (rec->fTextSize > SkIntToScalar(1 << 14)) {
rec->fTextSize = SkIntToScalar(1 << 14);
}
SkFontHinting h = rec->getHinting();
if (SkFontHinting::kFull == h && !isLCD(*rec)) {
// collapse full->normal hinting if we're not doing LCD
h = SkFontHinting::kNormal;
}
// rotated text looks bad with hinting, so we disable it as needed
if (!isAxisAligned(*rec)) {
h = SkFontHinting::kNone;
}
rec->setHinting(h);
#ifndef SK_GAMMA_APPLY_TO_A8
if (!isLCD(*rec)) {
// SRGBTODO: Is this correct? Do we want contrast boost?
rec->ignorePreBlend();
}
#endif
}
int SkTypeface_FreeType::GetUnitsPerEm(FT_Face face) {
SkASSERT(face);
SkScalar upem = SkIntToScalar(face->units_per_EM);
// At least some versions of FreeType set face->units_per_EM to 0 for bitmap only fonts.
if (upem == 0) {
TT_Header* ttHeader = (TT_Header*)FT_Get_Sfnt_Table(face, ft_sfnt_head);
if (ttHeader) {
upem = SkIntToScalar(ttHeader->Units_Per_EM);
}
}
return upem;
}
int SkTypeface_FreeType::onGetUPEM() const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return 0;
}
return GetUnitsPerEm(face);
}
bool SkTypeface_FreeType::onGetKerningPairAdjustments(const uint16_t glyphs[],
int count, int32_t adjustments[]) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face || !FT_HAS_KERNING(face)) {
return false;
}
for (int i = 0; i < count - 1; ++i) {
FT_Vector delta;
FT_Error err = FT_Get_Kerning(face, glyphs[i], glyphs[i+1],
FT_KERNING_UNSCALED, &delta);
if (err) {
return false;
}
adjustments[i] = delta.x;
}
return true;
}
/** Returns the bitmap strike equal to or just larger than the requested size. */
static FT_Int chooseBitmapStrike(FT_Face face, FT_F26Dot6 scaleY) {
if (face == nullptr) {
LOG_INFO("chooseBitmapStrike aborted due to nullptr face.\n");
return -1;
}
FT_Pos requestedPPEM = scaleY; // FT_Bitmap_Size::y_ppem is in 26.6 format.
FT_Int chosenStrikeIndex = -1;
FT_Pos chosenPPEM = 0;
for (FT_Int strikeIndex = 0; strikeIndex < face->num_fixed_sizes; ++strikeIndex) {
FT_Pos strikePPEM = face->available_sizes[strikeIndex].y_ppem;
if (strikePPEM == requestedPPEM) {
// exact match - our search stops here
return strikeIndex;
} else if (chosenPPEM < requestedPPEM) {
// attempt to increase chosenPPEM
if (chosenPPEM < strikePPEM) {
chosenPPEM = strikePPEM;
chosenStrikeIndex = strikeIndex;
}
} else {
// attempt to decrease chosenPPEM, but not below requestedPPEM
if (requestedPPEM < strikePPEM && strikePPEM < chosenPPEM) {
chosenPPEM = strikePPEM;
chosenStrikeIndex = strikeIndex;
}
}
}
return chosenStrikeIndex;
}
SkScalerContext_FreeType::SkScalerContext_FreeType(sk_sp<SkTypeface_FreeType> typeface,
const SkScalerContextEffects& effects,
const SkDescriptor* desc)
: SkScalerContext_FreeType_Base(std::move(typeface), effects, desc)
, fFace(nullptr)
, fFTSize(nullptr)
, fStrikeIndex(-1)
{
SkAutoMutexExclusive ac(f_t_mutex());
fFaceRec = static_cast<SkTypeface_FreeType*>(this->getTypeface())->getFaceRec();
// load the font file
if (nullptr == fFaceRec) {
LOG_INFO("Could not create FT_Face.\n");
return;
}
fLCDIsVert = SkToBool(fRec.fFlags & SkScalerContext::kLCD_Vertical_Flag);
// compute the flags we send to Load_Glyph
bool linearMetrics = this->isLinearMetrics();
{
FT_Int32 loadFlags = FT_LOAD_DEFAULT;
if (SkMask::kBW_Format == fRec.fMaskFormat) {
// See http://code.google.com/p/chromium/issues/detail?id=43252#c24
loadFlags = FT_LOAD_TARGET_MONO;
if (fRec.getHinting() == SkFontHinting::kNone) {
loadFlags |= FT_LOAD_NO_HINTING;
linearMetrics = true;
}
} else {
switch (fRec.getHinting()) {
case SkFontHinting::kNone:
loadFlags = FT_LOAD_NO_HINTING;
linearMetrics = true;
break;
case SkFontHinting::kSlight:
loadFlags = FT_LOAD_TARGET_LIGHT; // This implies FORCE_AUTOHINT
linearMetrics = true;
break;
case SkFontHinting::kNormal:
loadFlags = FT_LOAD_TARGET_NORMAL;
break;
case SkFontHinting::kFull:
loadFlags = FT_LOAD_TARGET_NORMAL;
if (isLCD(fRec)) {
if (fLCDIsVert) {
loadFlags = FT_LOAD_TARGET_LCD_V;
} else {
loadFlags = FT_LOAD_TARGET_LCD;
}
}
break;
default:
LOG_INFO("---------- UNKNOWN hinting %d\n", fRec.getHinting());
break;
}
}
if (fRec.fFlags & SkScalerContext::kForceAutohinting_Flag) {
loadFlags |= FT_LOAD_FORCE_AUTOHINT;
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
} else {
loadFlags |= FT_LOAD_NO_AUTOHINT;
#endif
}
if ((fRec.fFlags & SkScalerContext::kEmbeddedBitmapText_Flag) == 0) {
loadFlags |= FT_LOAD_NO_BITMAP;
}
// Always using FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH to get correct
// advances, as fontconfig and cairo do.
// See http://code.google.com/p/skia/issues/detail?id=222.
loadFlags |= FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH;
// Use vertical layout if requested.
if (this->isVertical()) {
loadFlags |= FT_LOAD_VERTICAL_LAYOUT;
}
fLoadGlyphFlags = loadFlags;
}
using DoneFTSize = SkFunctionWrapper<decltype(FT_Done_Size), FT_Done_Size>;
std::unique_ptr<std::remove_pointer_t<FT_Size>, DoneFTSize> ftSize([this]() -> FT_Size {
FT_Size size;
FT_Error err = FT_New_Size(fFaceRec->fFace.get(), &size);
if (err != 0) {
SK_TRACEFTR(err, "FT_New_Size(%s) failed.", fFaceRec->fFace->family_name);
return nullptr;
}
return size;
}());
if (nullptr == ftSize) {
LOG_INFO("Could not create FT_Size.\n");
return;
}
FT_Error err = FT_Activate_Size(ftSize.get());
if (err != 0) {
SK_TRACEFTR(err, "FT_Activate_Size(%s) failed.", fFaceRec->fFace->family_name);
return;
}
fRec.computeMatrices(SkScalerContextRec::PreMatrixScale::kFull, &fScale, &fMatrix22Scalar);
FT_F26Dot6 scaleX = SkScalarToFDot6(fScale.fX);
FT_F26Dot6 scaleY = SkScalarToFDot6(fScale.fY);
if (FT_IS_SCALABLE(fFaceRec->fFace)) {
err = FT_Set_Char_Size(fFaceRec->fFace.get(), scaleX, scaleY, 72, 72);
if (err != 0) {
SK_TRACEFTR(err, "FT_Set_CharSize(%s, %f, %f) failed.",
fFaceRec->fFace->family_name, fScale.fX, fScale.fY);
return;
}
// Adjust the matrix to reflect the actually chosen scale.
// FreeType currently does not allow requesting sizes less than 1, this allow for scaling.
// Don't do this at all sizes as that will interfere with hinting.
if (fScale.fX < 1 || fScale.fY < 1) {
SkScalar upem = fFaceRec->fFace->units_per_EM;
FT_Size_Metrics& ftmetrics = fFaceRec->fFace->size->metrics;
SkScalar x_ppem = upem * SkFT_FixedToScalar(ftmetrics.x_scale) / 64.0f;
SkScalar y_ppem = upem * SkFT_FixedToScalar(ftmetrics.y_scale) / 64.0f;
fMatrix22Scalar.preScale(fScale.x() / x_ppem, fScale.y() / y_ppem);
}
// FT_LOAD_COLOR with scalable fonts means allow SVG.
// It also implies attempt to render COLR if available, but this is not used.
#if defined(FT_CONFIG_OPTION_SVG)
if (SkGraphics::GetOpenTypeSVGDecoderFactory()) {
fLoadGlyphFlags |= FT_LOAD_COLOR;
}
#endif
} else if (FT_HAS_FIXED_SIZES(fFaceRec->fFace)) {
fStrikeIndex = chooseBitmapStrike(fFaceRec->fFace.get(), scaleY);
if (fStrikeIndex == -1) {
LOG_INFO("No glyphs for font \"%s\" size %f.\n",
fFaceRec->fFace->family_name, fScale.fY);
return;
}
err = FT_Select_Size(fFaceRec->fFace.get(), fStrikeIndex);
if (err != 0) {
SK_TRACEFTR(err, "FT_Select_Size(%s, %d) failed.",
fFaceRec->fFace->family_name, fStrikeIndex);
fStrikeIndex = -1;
return;
}
// Adjust the matrix to reflect the actually chosen scale.
// It is likely that the ppem chosen was not the one requested, this allows for scaling.
fMatrix22Scalar.preScale(fScale.x() / fFaceRec->fFace->size->metrics.x_ppem,
fScale.y() / fFaceRec->fFace->size->metrics.y_ppem);
// FreeType does not provide linear metrics for bitmap fonts.
linearMetrics = false;
// FreeType documentation says:
// FT_LOAD_NO_BITMAP -- Ignore bitmap strikes when loading.
// Bitmap-only fonts ignore this flag.
//
// However, in FreeType 2.5.1 color bitmap only fonts do not ignore this flag.
// Force this flag off for bitmap only fonts.
fLoadGlyphFlags &= ~FT_LOAD_NO_BITMAP;
// Color bitmaps are supported.
fLoadGlyphFlags |= FT_LOAD_COLOR;
} else {
LOG_INFO("Unknown kind of font \"%s\" size %f.\n", fFaceRec->fFace->family_name, fScale.fY);
return;
}
fMatrix22.xx = SkScalarToFixed(fMatrix22Scalar.getScaleX());
fMatrix22.xy = SkScalarToFixed(-fMatrix22Scalar.getSkewX());
fMatrix22.yx = SkScalarToFixed(-fMatrix22Scalar.getSkewY());
fMatrix22.yy = SkScalarToFixed(fMatrix22Scalar.getScaleY());
fFTSize = ftSize.release();
fFace = fFaceRec->fFace.get();
fDoLinearMetrics = linearMetrics;
}
SkScalerContext_FreeType::~SkScalerContext_FreeType() {
SkAutoMutexExclusive ac(f_t_mutex());
if (fFTSize != nullptr) {
FT_Done_Size(fFTSize);
}
fFaceRec = nullptr;
}
/* We call this before each use of the fFace, since we may be sharing
this face with other context (at different sizes).
*/
FT_Error SkScalerContext_FreeType::setupSize() {
f_t_mutex().assertHeld();
FT_Error err = FT_Activate_Size(fFTSize);
if (err != 0) {
return err;
}
FT_Set_Transform(fFace, &fMatrix22, nullptr);
return 0;
}
bool SkScalerContext_FreeType::generateAdvance(SkGlyph* glyph) {
/* unhinted and light hinted text have linearly scaled advances
* which are very cheap to compute with some font formats...
*/
if (!fDoLinearMetrics) {
return false;
}
SkAutoMutexExclusive ac(f_t_mutex());
if (this->setupSize()) {
glyph->zeroMetrics();
return true;
}
FT_Error error;
FT_Fixed advance;
error = FT_Get_Advance( fFace, glyph->getGlyphID(),
fLoadGlyphFlags | FT_ADVANCE_FLAG_FAST_ONLY,
&advance );
if (error != 0) {
return false;
}
const SkScalar advanceScalar = SkFT_FixedToScalar(advance);
glyph->fAdvanceX = SkScalarToFloat(fMatrix22Scalar.getScaleX() * advanceScalar);
glyph->fAdvanceY = SkScalarToFloat(fMatrix22Scalar.getSkewY() * advanceScalar);
return true;
}
bool SkScalerContext_FreeType::getBoundsOfCurrentOutlineGlyph(FT_GlyphSlot glyph, SkRect* bounds) {
if (glyph->format != FT_GLYPH_FORMAT_OUTLINE) {
SkASSERT(false);
return false;
}
if (0 == glyph->outline.n_contours) {
return false;
}
FT_BBox bbox;
FT_Outline_Get_CBox(&glyph->outline, &bbox);
*bounds = SkRect::MakeLTRB(SkFDot6ToScalar(bbox.xMin), -SkFDot6ToScalar(bbox.yMax),
SkFDot6ToScalar(bbox.xMax), -SkFDot6ToScalar(bbox.yMin));
return true;
}
bool SkScalerContext_FreeType::getCBoxForLetter(char letter, FT_BBox* bbox) {
const FT_UInt glyph_id = FT_Get_Char_Index(fFace, letter);
if (!glyph_id) {
return false;
}
if (FT_Load_Glyph(fFace, glyph_id, fLoadGlyphFlags)) {
return false;
}
if (fFace->glyph->format != FT_GLYPH_FORMAT_OUTLINE) {
return false;
}
emboldenIfNeeded(fFace, fFace->glyph, SkTo<SkGlyphID>(glyph_id));
FT_Outline_Get_CBox(&fFace->glyph->outline, bbox);
return true;
}
void SkScalerContext_FreeType::setGlyphBounds(SkGlyph* glyph, SkRect* bounds, bool subpixel) {
SkIRect irect;
if (bounds->isEmpty()) {
irect = SkIRect::MakeEmpty();
} else {
if (subpixel) {
bounds->offset(SkFixedToScalar(glyph->getSubXFixed()),
SkFixedToScalar(glyph->getSubYFixed()));
}
irect = bounds->roundOut();
if (!SkTFitsIn<decltype(glyph->fWidth )>(irect.width ()) ||
!SkTFitsIn<decltype(glyph->fHeight)>(irect.height()) ||
!SkTFitsIn<decltype(glyph->fTop )>(irect.top ()) ||
!SkTFitsIn<decltype(glyph->fLeft )>(irect.left ()) )
{
irect = SkIRect::MakeEmpty();
}
}
glyph->fWidth = SkToU16(irect.width ());
glyph->fHeight = SkToU16(irect.height());
glyph->fTop = SkToS16(irect.top ());
glyph->fLeft = SkToS16(irect.left ());
}
void SkScalerContext_FreeType::updateGlyphBoundsIfLCD(SkGlyph* glyph) {
if (glyph->fMaskFormat == SkMask::kLCD16_Format &&
glyph->fWidth > 0 && glyph->fHeight > 0)
{
if (fLCDIsVert) {
glyph->fHeight += 2;
glyph->fTop -= 1;
} else {
glyph->fWidth += 2;
glyph->fLeft -= 1;
}
}
}
bool SkScalerContext_FreeType::shouldSubpixelBitmap(const SkGlyph& glyph, const SkMatrix& matrix) {
// If subpixel rendering of a bitmap *can* be done.
bool mechanism = fFace->glyph->format == FT_GLYPH_FORMAT_BITMAP &&
this->isSubpixel() &&
(glyph.getSubXFixed() || glyph.getSubYFixed());
// If subpixel rendering of a bitmap *should* be done.
// 1. If the face is not scalable then always allow subpixel rendering.
// Otherwise, if the font has an 8ppem strike 7 will subpixel render but 8 won't.
// 2. If the matrix is already not identity the bitmap will already be resampled,
// so resampling slightly differently shouldn't make much difference.
bool policy = !FT_IS_SCALABLE(fFace) || !matrix.isIdentity();
return mechanism && policy;
}
void SkScalerContext_FreeType::generateMetrics(SkGlyph* glyph, SkArenaAlloc* alloc) {
SkAutoMutexExclusive ac(f_t_mutex());
if (this->setupSize()) {
glyph->zeroMetrics();
return;
}
FT_Bool haveLayers = false;
#ifdef FT_COLOR_H
// See https://skbug.com/12945, if the face isn't marked scalable then paths cannot be loaded.
if (FT_IS_SCALABLE(fFace)) {
SkRect bounds = SkRect::MakeEmpty();
#ifdef TT_SUPPORT_COLRV1
FT_OpaquePaint opaqueLayerPaint{nullptr, 1};
if (FT_Get_Color_Glyph_Paint(fFace, glyph->getGlyphID(),
FT_COLOR_INCLUDE_ROOT_TRANSFORM, &opaqueLayerPaint)) {
haveLayers = true;
glyph->fScalerContextBits = ScalerContextBits::COLRv1;
// COLRv1 optionally provides a ClipBox.
FT_ClipBox clipBox;
if (FT_Get_Color_Glyph_ClipBox(fFace, glyph->getGlyphID(), &clipBox)) {
// Find bounding box of clip box corner points, needed when clipbox is transformed.
FT_BBox bbox;
bbox.xMin = clipBox.bottom_left.x;
bbox.xMax = clipBox.bottom_left.x;
bbox.yMin = clipBox.bottom_left.y;
bbox.yMax = clipBox.bottom_left.y;
for (auto& corner : {clipBox.top_left, clipBox.top_right, clipBox.bottom_right}) {
bbox.xMin = std::min(bbox.xMin, corner.x);
bbox.yMin = std::min(bbox.yMin, corner.y);
bbox.xMax = std::max(bbox.xMax, corner.x);
bbox.yMax = std::max(bbox.yMax, corner.y);
}
bounds = SkRect::MakeLTRB(SkFDot6ToScalar(bbox.xMin), -SkFDot6ToScalar(bbox.yMax),
SkFDot6ToScalar(bbox.xMax), -SkFDot6ToScalar(bbox.yMin));
} else {
// Traverse the glyph graph with a focus on measuring the required bounding box.
// The call to computeColrV1GlyphBoundingBox may modify the face.
// Reset the face to load the base glyph for metrics.
if (!computeColrV1GlyphBoundingBox(fFace, glyph->getGlyphID(), &bounds) ||
this->setupSize())
{
glyph->zeroMetrics();
return;
}
}
}
#endif // #TT_SUPPORT_COLRV1
if (!haveLayers) {
FT_LayerIterator layerIterator = { 0, 0, nullptr };
FT_UInt layerGlyphIndex;
FT_UInt layerColorIndex;
FT_Int32 flags = fLoadGlyphFlags;
flags |= FT_LOAD_BITMAP_METRICS_ONLY; // Don't decode any bitmaps.
flags |= FT_LOAD_NO_BITMAP; // Ignore embedded bitmaps.
flags &= ~FT_LOAD_RENDER; // Don't scan convert.
flags &= ~FT_LOAD_COLOR; // Ignore SVG.
// For COLRv0 compute the glyph bounding box from the union of layer bounding boxes.
while (FT_Get_Color_Glyph_Layer(fFace, glyph->getGlyphID(), &layerGlyphIndex,
&layerColorIndex, &layerIterator)) {
haveLayers = true;
if (FT_Load_Glyph(fFace, layerGlyphIndex, flags)) {
glyph->zeroMetrics();
return;
}
SkRect currentBounds;
if (getBoundsOfCurrentOutlineGlyph(fFace->glyph, &currentBounds)) {
bounds.join(currentBounds);
}
}
if (haveLayers) {
glyph->fScalerContextBits = ScalerContextBits::COLRv0;
}
}
if (haveLayers) {
glyph->fMaskFormat = SkMask::kARGB32_Format;
glyph->setPath(alloc, nullptr, false);
setGlyphBounds(glyph, &bounds, this->isSubpixel());
}
}
#endif //FT_COLOR_H
// Even if haveLayers, the base glyph must be loaded to get the metrics.
if (FT_Load_Glyph(fFace, glyph->getGlyphID(), fLoadGlyphFlags | FT_LOAD_BITMAP_METRICS_ONLY)) {
glyph->zeroMetrics();
return;
}
if (!haveLayers) {
emboldenIfNeeded(fFace, fFace->glyph, glyph->getGlyphID());
if (fFace->glyph->format == FT_GLYPH_FORMAT_OUTLINE) {
SkRect bounds;
if (!getBoundsOfCurrentOutlineGlyph(fFace->glyph, &bounds)) {
bounds = SkRect::MakeEmpty();
}
setGlyphBounds(glyph, &bounds, this->isSubpixel());
updateGlyphBoundsIfLCD(glyph);
} else if (fFace->glyph->format == FT_GLYPH_FORMAT_BITMAP) {
glyph->setPath(alloc, nullptr, false);
if (this->isVertical()) {
FT_Vector vector;
vector.x = fFace->glyph->metrics.vertBearingX - fFace->glyph->metrics.horiBearingX;
vector.y = -fFace->glyph->metrics.vertBearingY - fFace->glyph->metrics.horiBearingY;
FT_Vector_Transform(&vector, &fMatrix22);
fFace->glyph->bitmap_left += SkFDot6Floor(vector.x);
fFace->glyph->bitmap_top += SkFDot6Floor(vector.y);
}
if (fFace->glyph->bitmap.pixel_mode == FT_PIXEL_MODE_BGRA) {
glyph->fMaskFormat = SkMask::kARGB32_Format;
}
SkRect bounds = SkRect::MakeXYWH(SkIntToScalar(fFace->glyph->bitmap_left ),
-SkIntToScalar(fFace->glyph->bitmap_top ),
SkIntToScalar(fFace->glyph->bitmap.width),
SkIntToScalar(fFace->glyph->bitmap.rows ));
fMatrix22Scalar.mapRect(&bounds);
setGlyphBounds(glyph, &bounds, this->shouldSubpixelBitmap(*glyph, fMatrix22Scalar));
#if defined(FT_CONFIG_OPTION_SVG)
} else if (fFace->glyph->format == FT_GLYPH_FORMAT_SVG) {
glyph->fScalerContextBits = ScalerContextBits::SVG;
glyph->fMaskFormat = SkMask::kARGB32_Format;
glyph->setPath(alloc, nullptr, false);
SkPictureRecorder recorder;
SkRect infiniteRect = SkRect::MakeLTRB(-SK_ScalarInfinity, -SK_ScalarInfinity,
SK_ScalarInfinity, SK_ScalarInfinity);
sk_sp<SkBBoxHierarchy> bboxh = SkRTreeFactory()();
SkSpan<SkColor> palette(fFaceRec->fSkPalette.get(), fFaceRec->fFTPaletteEntryCount);
SkCanvas* recordingCanvas = recorder.beginRecording(infiniteRect, bboxh);
if (!this->drawSVGGlyph(fFace, *glyph, fLoadGlyphFlags, palette, recordingCanvas)) {
glyph->zeroMetrics();
return;
}
sk_sp<SkPicture> pic = recorder.finishRecordingAsPicture();
SkRect bounds = pic->cullRect();
SkASSERT(bounds.isFinite());
// drawSVGGlyph already applied the subpixel positioning.
setGlyphBounds(glyph, &bounds, false);
#endif // FT_CONFIG_OPTION_SVG
} else {
SkDEBUGFAIL("unknown glyph format");
glyph->zeroMetrics();
return;
}
}
if (this->isVertical()) {
if (fDoLinearMetrics) {
const SkScalar advanceScalar = SkFT_FixedToScalar(fFace->glyph->linearVertAdvance);
glyph->fAdvanceX = SkScalarToFloat(fMatrix22Scalar.getSkewX() * advanceScalar);
glyph->fAdvanceY = SkScalarToFloat(fMatrix22Scalar.getScaleY() * advanceScalar);
} else {
glyph->fAdvanceX = -SkFDot6ToFloat(fFace->glyph->advance.x);
glyph->fAdvanceY = SkFDot6ToFloat(fFace->glyph->advance.y);
}
} else {
if (fDoLinearMetrics) {
const SkScalar advanceScalar = SkFT_FixedToScalar(fFace->glyph->linearHoriAdvance);
glyph->fAdvanceX = SkScalarToFloat(fMatrix22Scalar.getScaleX() * advanceScalar);
glyph->fAdvanceY = SkScalarToFloat(fMatrix22Scalar.getSkewY() * advanceScalar);
} else {
glyph->fAdvanceX = SkFDot6ToFloat(fFace->glyph->advance.x);
glyph->fAdvanceY = -SkFDot6ToFloat(fFace->glyph->advance.y);
}
}
#ifdef ENABLE_GLYPH_SPEW
LOG_INFO("Metrics(glyph:%d flags:0x%x) w:%d\n", glyph->getGlyphID(), fLoadGlyphFlags, glyph->fWidth);
#endif
}
void SkScalerContext_FreeType::generateImage(const SkGlyph& glyph) {
SkAutoMutexExclusive ac(f_t_mutex());
if (this->setupSize()) {
sk_bzero(glyph.fImage, glyph.imageSize());
return;
}
if (glyph.fScalerContextBits == ScalerContextBits::COLRv0 ||
glyph.fScalerContextBits == ScalerContextBits::COLRv1 ||
glyph.fScalerContextBits == ScalerContextBits::SVG )
{
SkASSERT(glyph.maskFormat() == SkMask::kARGB32_Format);
SkBitmap dstBitmap;
// TODO: mark this as sRGB when the blits will be sRGB.
dstBitmap.setInfo(SkImageInfo::Make(glyph.fWidth, glyph.fHeight,
kN32_SkColorType,
kPremul_SkAlphaType),
glyph.rowBytes());
dstBitmap.setPixels(glyph.fImage);
SkCanvas canvas(dstBitmap);
if constexpr (kSkShowTextBlitCoverage) {
canvas.clear(0x33FF0000);
} else {
canvas.clear(SK_ColorTRANSPARENT);
}
canvas.translate(-glyph.fLeft, -glyph.fTop);
SkSpan<SkColor> palette(fFaceRec->fSkPalette.get(), fFaceRec->fFTPaletteEntryCount);
if (glyph.fScalerContextBits == ScalerContextBits::COLRv0) {
#ifdef FT_COLOR_H
this->drawCOLRv0Glyph(fFace, glyph, fLoadGlyphFlags, palette, &canvas);
#endif
} else if (glyph.fScalerContextBits == ScalerContextBits::COLRv1) {
#ifdef TT_SUPPORT_COLRV1
this->drawCOLRv1Glyph(fFace, glyph, fLoadGlyphFlags, palette, &canvas);
#endif
} else if (glyph.fScalerContextBits == ScalerContextBits::SVG) {
#if defined(FT_CONFIG_OPTION_SVG)
if (FT_Load_Glyph(fFace, glyph.getGlyphID(), fLoadGlyphFlags)) {
return;
}
this->drawSVGGlyph(fFace, glyph, fLoadGlyphFlags, palette, &canvas);
#endif
}
return;
}
if (FT_Load_Glyph(fFace, glyph.getGlyphID(), fLoadGlyphFlags)) {
sk_bzero(glyph.fImage, glyph.imageSize());
return;
}
emboldenIfNeeded(fFace, fFace->glyph, glyph.getGlyphID());
SkMatrix* bitmapMatrix = &fMatrix22Scalar;
SkMatrix subpixelBitmapMatrix;
if (this->shouldSubpixelBitmap(glyph, *bitmapMatrix)) {
subpixelBitmapMatrix = fMatrix22Scalar;
subpixelBitmapMatrix.postTranslate(SkFixedToScalar(glyph.getSubXFixed()),
SkFixedToScalar(glyph.getSubYFixed()));
bitmapMatrix = &subpixelBitmapMatrix;
}
generateGlyphImage(fFace, glyph, *bitmapMatrix);
}
sk_sp<SkDrawable> SkScalerContext_FreeType::generateDrawable(const SkGlyph& glyph) {
// Because FreeType's FT_Face is stateful (not thread safe) and the current design of this
// SkTypeface and SkScalerContext does not work around this, it is necessary lock at least the
// FT_Face when using it (this implementation currently locks the whole FT_Library).
// It should be possible to draw the drawable straight out of the FT_Face. However, this would
// mean locking each time any such drawable is drawn. To avoid locking, this implementation
// creates drawables backed as pictures so that they can be played back later without locking.
SkAutoMutexExclusive ac(f_t_mutex());
if (this->setupSize()) {
sk_bzero(glyph.fImage, glyph.imageSize());
return nullptr;
}
#if defined(FT_COLOR_H) || defined(TT_SUPPORT_COLRV1) || defined(FT_CONFIG_OPTION_SVG)
if (glyph.fScalerContextBits == ScalerContextBits::COLRv0 ||
glyph.fScalerContextBits == ScalerContextBits::COLRv1 ||
glyph.fScalerContextBits == ScalerContextBits::SVG )
{
SkSpan<SkColor> palette(fFaceRec->fSkPalette.get(), fFaceRec->fFTPaletteEntryCount);
SkPictureRecorder recorder;
SkCanvas* recordingCanvas = recorder.beginRecording(SkRect::Make(glyph.mask().fBounds));
if (glyph.fScalerContextBits == ScalerContextBits::COLRv0) {
#ifdef FT_COLOR_H
if (!this->drawCOLRv0Glyph(fFace, glyph, fLoadGlyphFlags, palette, recordingCanvas)) {
return nullptr;
}
#else
return nullptr;
#endif
} else if (glyph.fScalerContextBits == ScalerContextBits::COLRv1) {
#ifdef TT_SUPPORT_COLRV1
if (!this->drawCOLRv1Glyph(fFace, glyph, fLoadGlyphFlags, palette, recordingCanvas)) {
return nullptr;
}
#else
return nullptr;
#endif
} else if (glyph.fScalerContextBits == ScalerContextBits::SVG) {
#if defined(FT_CONFIG_OPTION_SVG)
if (FT_Load_Glyph(fFace, glyph.getGlyphID(), fLoadGlyphFlags)) {
return nullptr;
}
if (!this->drawSVGGlyph(fFace, glyph, fLoadGlyphFlags, palette, recordingCanvas)) {
return nullptr;
}
#else
return nullptr;
#endif
}
return recorder.finishRecordingAsDrawable();
}
#endif
return nullptr;
}
bool SkScalerContext_FreeType::generatePath(const SkGlyph& glyph, SkPath* path) {
SkASSERT(path);
SkAutoMutexExclusive ac(f_t_mutex());
SkGlyphID glyphID = glyph.getGlyphID();
// FT_IS_SCALABLE is documented to mean the face contains outline glyphs.
if (!FT_IS_SCALABLE(fFace) || this->setupSize()) {
path->reset();
return false;
}
uint32_t flags = fLoadGlyphFlags;
flags |= FT_LOAD_NO_BITMAP; // ignore embedded bitmaps so we're sure to get the outline
flags &= ~FT_LOAD_RENDER; // don't scan convert (we just want the outline)
FT_Error err = FT_Load_Glyph(fFace, glyphID, flags);
if (err != 0 || fFace->glyph->format != FT_GLYPH_FORMAT_OUTLINE) {
path->reset();
return false;
}
emboldenIfNeeded(fFace, fFace->glyph, glyphID);
if (!generateGlyphPath(fFace, path)) {
path->reset();
return false;
}
// The path's origin from FreeType is always the horizontal layout origin.
// Offset the path so that it is relative to the vertical origin if needed.
if (this->isVertical()) {
FT_Vector vector;
vector.x = fFace->glyph->metrics.vertBearingX - fFace->glyph->metrics.horiBearingX;
vector.y = -fFace->glyph->metrics.vertBearingY - fFace->glyph->metrics.horiBearingY;
FT_Vector_Transform(&vector, &fMatrix22);
path->offset(SkFDot6ToScalar(vector.x), -SkFDot6ToScalar(vector.y));
}
return true;
}
void SkScalerContext_FreeType::generateFontMetrics(SkFontMetrics* metrics) {
if (nullptr == metrics) {
return;
}
SkAutoMutexExclusive ac(f_t_mutex());
if (this->setupSize()) {
sk_bzero(metrics, sizeof(*metrics));
return;
}
FT_Face face = fFace;
metrics->fFlags = 0;
SkScalar upem = SkIntToScalar(SkTypeface_FreeType::GetUnitsPerEm(face));
// use the os/2 table as a source of reasonable defaults.
SkScalar x_height = 0.0f;
SkScalar avgCharWidth = 0.0f;
SkScalar cap_height = 0.0f;
SkScalar strikeoutThickness = 0.0f, strikeoutPosition = 0.0f;
TT_OS2* os2 = (TT_OS2*) FT_Get_Sfnt_Table(face, ft_sfnt_os2);
if (os2) {
x_height = SkIntToScalar(os2->sxHeight) / upem * fScale.y();
avgCharWidth = SkIntToScalar(os2->xAvgCharWidth) / upem;
strikeoutThickness = SkIntToScalar(os2->yStrikeoutSize) / upem;
strikeoutPosition = -SkIntToScalar(os2->yStrikeoutPosition) / upem;
metrics->fFlags |= SkFontMetrics::kStrikeoutThicknessIsValid_Flag;
metrics->fFlags |= SkFontMetrics::kStrikeoutPositionIsValid_Flag;
if (os2->version != 0xFFFF && os2->version >= 2) {
cap_height = SkIntToScalar(os2->sCapHeight) / upem * fScale.y();
}
}
// pull from format-specific metrics as needed
SkScalar ascent, descent, leading, xmin, xmax, ymin, ymax;
SkScalar underlineThickness, underlinePosition;
if (face->face_flags & FT_FACE_FLAG_SCALABLE) { // scalable outline font
// FreeType will always use HHEA metrics if they're not zero.
// It completely ignores the OS/2 fsSelection::UseTypoMetrics bit.
// It also ignores the VDMX tables, which are also of interest here
// (and override everything else when they apply).
static const int kUseTypoMetricsMask = (1 << 7);
if (os2 && os2->version != 0xFFFF && (os2->fsSelection & kUseTypoMetricsMask)) {
ascent = -SkIntToScalar(os2->sTypoAscender) / upem;
descent = -SkIntToScalar(os2->sTypoDescender) / upem;
leading = SkIntToScalar(os2->sTypoLineGap) / upem;
} else {
ascent = -SkIntToScalar(face->ascender) / upem;
descent = -SkIntToScalar(face->descender) / upem;
leading = SkIntToScalar(face->height + (face->descender - face->ascender)) / upem;
}
xmin = SkIntToScalar(face->bbox.xMin) / upem;
xmax = SkIntToScalar(face->bbox.xMax) / upem;
ymin = -SkIntToScalar(face->bbox.yMin) / upem;
ymax = -SkIntToScalar(face->bbox.yMax) / upem;
underlineThickness = SkIntToScalar(face->underline_thickness) / upem;
underlinePosition = -SkIntToScalar(face->underline_position +
face->underline_thickness / 2) / upem;
metrics->fFlags |= SkFontMetrics::kUnderlineThicknessIsValid_Flag;
metrics->fFlags |= SkFontMetrics::kUnderlinePositionIsValid_Flag;
// we may be able to synthesize x_height and cap_height from outline
if (!x_height) {
FT_BBox bbox;
if (getCBoxForLetter('x', &bbox)) {
x_height = SkIntToScalar(bbox.yMax) / 64.0f;
}
}
if (!cap_height) {
FT_BBox bbox;
if (getCBoxForLetter('H', &bbox)) {
cap_height = SkIntToScalar(bbox.yMax) / 64.0f;
}
}
} else if (fStrikeIndex != -1) { // bitmap strike metrics
SkScalar xppem = SkIntToScalar(face->size->metrics.x_ppem);
SkScalar yppem = SkIntToScalar(face->size->metrics.y_ppem);
ascent = -SkIntToScalar(face->size->metrics.ascender) / (yppem * 64.0f);
descent = -SkIntToScalar(face->size->metrics.descender) / (yppem * 64.0f);
leading = (SkIntToScalar(face->size->metrics.height) / (yppem * 64.0f)) + ascent - descent;
xmin = 0.0f;
xmax = SkIntToScalar(face->available_sizes[fStrikeIndex].width) / xppem;
ymin = descent;
ymax = ascent;
// The actual bitmaps may be any size and placed at any offset.
metrics->fFlags |= SkFontMetrics::kBoundsInvalid_Flag;
underlineThickness = 0;
underlinePosition = 0;
metrics->fFlags &= ~SkFontMetrics::kUnderlineThicknessIsValid_Flag;
metrics->fFlags &= ~SkFontMetrics::kUnderlinePositionIsValid_Flag;
TT_Postscript* post = (TT_Postscript*) FT_Get_Sfnt_Table(face, ft_sfnt_post);
if (post) {
underlineThickness = SkIntToScalar(post->underlineThickness) / upem;
underlinePosition = -SkIntToScalar(post->underlinePosition) / upem;
metrics->fFlags |= SkFontMetrics::kUnderlineThicknessIsValid_Flag;
metrics->fFlags |= SkFontMetrics::kUnderlinePositionIsValid_Flag;
}
} else {
sk_bzero(metrics, sizeof(*metrics));
return;
}
// synthesize elements that were not provided by the os/2 table or format-specific metrics
if (!x_height) {
x_height = -ascent * fScale.y();
}
if (!avgCharWidth) {
avgCharWidth = xmax - xmin;
}
if (!cap_height) {
cap_height = -ascent * fScale.y();
}
// disallow negative linespacing
if (leading < 0.0f) {
leading = 0.0f;
}
metrics->fTop = ymax * fScale.y();
metrics->fAscent = ascent * fScale.y();
metrics->fDescent = descent * fScale.y();
metrics->fBottom = ymin * fScale.y();
metrics->fLeading = leading * fScale.y();
metrics->fAvgCharWidth = avgCharWidth * fScale.y();
metrics->fXMin = xmin * fScale.y();
metrics->fXMax = xmax * fScale.y();
metrics->fMaxCharWidth = metrics->fXMax - metrics->fXMin;
metrics->fXHeight = x_height;
metrics->fCapHeight = cap_height;
metrics->fUnderlineThickness = underlineThickness * fScale.y();
metrics->fUnderlinePosition = underlinePosition * fScale.y();
metrics->fStrikeoutThickness = strikeoutThickness * fScale.y();
metrics->fStrikeoutPosition = strikeoutPosition * fScale.y();
if (face->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS
#if defined(FT_CONFIG_OPTION_SVG)
|| face->face_flags & FT_FACE_FLAG_SVG
#endif // FT_CONFIG_OPTION_SVG
) {
// The bounds are only valid for the default variation of variable glyphs.
// https://docs.microsoft.com/en-us/typography/opentype/spec/head
// For SVG glyphs this number is often incorrect for its non-`glyf` points.
// https://github.com/fonttools/fonttools/issues/2566
metrics->fFlags |= SkFontMetrics::kBoundsInvalid_Flag;
}
}
///////////////////////////////////////////////////////////////////////////////
// hand-tuned value to reduce outline embolden strength
#ifndef SK_OUTLINE_EMBOLDEN_DIVISOR
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
#define SK_OUTLINE_EMBOLDEN_DIVISOR 34
#else
#define SK_OUTLINE_EMBOLDEN_DIVISOR 24
#endif
#endif
///////////////////////////////////////////////////////////////////////////////
void SkScalerContext_FreeType::emboldenIfNeeded(FT_Face face, FT_GlyphSlot glyph, SkGlyphID gid) {
// check to see if the embolden bit is set
if (0 == (fRec.fFlags & SkScalerContext::kEmbolden_Flag)) {
return;
}
switch (glyph->format) {
case FT_GLYPH_FORMAT_OUTLINE:
FT_Pos strength;
strength = FT_MulFix(face->units_per_EM, face->size->metrics.y_scale)
/ SK_OUTLINE_EMBOLDEN_DIVISOR;
FT_Outline_Embolden(&glyph->outline, strength);
break;
case FT_GLYPH_FORMAT_BITMAP:
if (!fFace->glyph->bitmap.buffer) {
FT_Load_Glyph(fFace, gid, fLoadGlyphFlags);
}
FT_GlyphSlot_Own_Bitmap(glyph);
FT_Bitmap_Embolden(glyph->library, &glyph->bitmap, kBitmapEmboldenStrength, 0);
break;
default:
SkDEBUGFAIL("unknown glyph format");
}
}
///////////////////////////////////////////////////////////////////////////////
#include "src/core/SkUtils.h"
SkTypeface_FreeType::SkTypeface_FreeType(const SkFontStyle& style, bool isFixedPitch)
: INHERITED(style, isFixedPitch)
{}
SkTypeface_FreeType::~SkTypeface_FreeType() {
if (fFaceRec) {
SkAutoMutexExclusive ac(f_t_mutex());
fFaceRec.reset();
}
}
// Just made up, so we don't end up storing 1000s of entries
constexpr int kMaxC2GCacheCount = 512;
void SkTypeface_FreeType::onCharsToGlyphs(const SkUnichar uni[], int count,
SkGlyphID glyphs[]) const {
// Try the cache first, *before* accessing freetype lib/face, as that
// can be very slow. If we do need to compute a new glyphID, then
// access those freetype objects and continue the loop.
int i;
{
// Optimistically use a shared lock.
SkAutoSharedMutexShared ama(fC2GCacheMutex);
for (i = 0; i < count; ++i) {
int index = fC2GCache.findGlyphIndex(uni[i]);
if (index < 0) {
break;
}
glyphs[i] = SkToU16(index);
}
if (i == count) {
// we're done, no need to access the freetype objects
return;
}
}
// Need to add more so grab an exclusive lock.
SkAutoSharedMutexExclusive ama(fC2GCacheMutex);
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
sk_bzero(glyphs, count * sizeof(glyphs[0]));
return;
}
for (; i < count; ++i) {
SkUnichar c = uni[i];
int index = fC2GCache.findGlyphIndex(c);
if (index >= 0) {
glyphs[i] = SkToU16(index);
} else {
glyphs[i] = SkToU16(FT_Get_Char_Index(face, c));
fC2GCache.insertCharAndGlyph(~index, c, glyphs[i]);
}
}
if (fC2GCache.count() > kMaxC2GCacheCount) {
fC2GCache.reset();
}
}
int SkTypeface_FreeType::onCountGlyphs() const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
return face ? face->num_glyphs : 0;
}
SkTypeface::LocalizedStrings* SkTypeface_FreeType::onCreateFamilyNameIterator() const {
sk_sp<SkTypeface::LocalizedStrings> nameIter =
SkOTUtils::LocalizedStrings_NameTable::MakeForFamilyNames(*this);
if (!nameIter) {
SkString familyName;
this->getFamilyName(&familyName);
SkString language("und"); //undetermined
nameIter = sk_make_sp<SkOTUtils::LocalizedStrings_SingleName>(familyName, language);
}
return nameIter.release();
}
bool SkTypeface_FreeType::onGlyphMaskNeedsCurrentColor() const {
fGlyphMasksMayNeedCurrentColorOnce([this]{
static constexpr SkFourByteTag COLRTag = SkSetFourByteTag('C', 'O', 'L', 'R');
fGlyphMasksMayNeedCurrentColor = this->getTableSize(COLRTag) > 0;
#if defined(FT_CONFIG_OPTION_SVG)
static constexpr SkFourByteTag SVGTag = SkSetFourByteTag('S', 'V', 'G', ' ');
fGlyphMasksMayNeedCurrentColor |= this->getTableSize(SVGTag) > 0 ;
#endif // FT_CONFIG_OPTION_SVG
});
return fGlyphMasksMayNeedCurrentColor;
}
int SkTypeface_FreeType::onGetVariationDesignPosition(
SkFontArguments::VariationPosition::Coordinate coordinates[], int coordinateCount) const
{
AutoFTAccess fta(this);
return GetVariationDesignPosition(fta, coordinates, coordinateCount);
}
int SkTypeface_FreeType::onGetVariationDesignParameters(
SkFontParameters::Variation::Axis parameters[], int parameterCount) const
{
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return -1;
}
if (!(face->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS)) {
return 0;
}
FT_MM_Var* variations = nullptr;
if (FT_Get_MM_Var(face, &variations)) {
return -1;
}
SkAutoFree autoFreeVariations(variations);
if (!parameters || parameterCount < SkToInt(variations->num_axis)) {
return variations->num_axis;
}
for (FT_UInt i = 0; i < variations->num_axis; ++i) {
parameters[i].tag = variations->axis[i].tag;
parameters[i].min = SkFixedToScalar(variations->axis[i].minimum);
parameters[i].def = SkFixedToScalar(variations->axis[i].def);
parameters[i].max = SkFixedToScalar(variations->axis[i].maximum);
FT_UInt flags = 0;
bool hidden = !FT_Get_Var_Axis_Flags(variations, i, &flags) &&
(flags & FT_VAR_AXIS_FLAG_HIDDEN);
parameters[i].setHidden(hidden);
}
return variations->num_axis;
}
int SkTypeface_FreeType::onGetTableTags(SkFontTableTag tags[]) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return 0;
}
FT_ULong tableCount = 0;
FT_Error error;
// When 'tag' is nullptr, returns number of tables in 'length'.
error = FT_Sfnt_Table_Info(face, 0, nullptr, &tableCount);
if (error) {
return 0;
}
if (tags) {
for (FT_ULong tableIndex = 0; tableIndex < tableCount; ++tableIndex) {
FT_ULong tableTag;
FT_ULong tablelength;
error = FT_Sfnt_Table_Info(face, tableIndex, &tableTag, &tablelength);
if (error) {
return 0;
}
tags[tableIndex] = static_cast<SkFontTableTag>(tableTag);
}
}
return tableCount;
}
size_t SkTypeface_FreeType::onGetTableData(SkFontTableTag tag, size_t offset,
size_t length, void* data) const
{
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return 0;
}
FT_ULong tableLength = 0;
FT_Error error;
// When 'length' is 0 it is overwritten with the full table length; 'offset' is ignored.
error = FT_Load_Sfnt_Table(face, tag, 0, nullptr, &tableLength);
if (error) {
return 0;
}
if (offset > tableLength) {
return 0;
}
FT_ULong size = std::min((FT_ULong)length, tableLength - (FT_ULong)offset);
if (data) {
error = FT_Load_Sfnt_Table(face, tag, offset, reinterpret_cast<FT_Byte*>(data), &size);
if (error) {
return 0;
}
}
return size;
}
sk_sp<SkData> SkTypeface_FreeType::onCopyTableData(SkFontTableTag tag) const {
AutoFTAccess fta(this);
FT_Face face = fta.face();
if (!face) {
return nullptr;
}
FT_ULong tableLength = 0;
FT_Error error;
// When 'length' is 0 it is overwritten with the full table length; 'offset' is ignored.
error = FT_Load_Sfnt_Table(face, tag, 0, nullptr, &tableLength);
if (error) {
return nullptr;
}
sk_sp<SkData> data = SkData::MakeUninitialized(tableLength);
if (data) {
error = FT_Load_Sfnt_Table(face, tag, 0,
reinterpret_cast<FT_Byte*>(data->writable_data()), &tableLength);
if (error) {
data.reset();
}
}
return data;
}
SkTypeface_FreeType::FaceRec* SkTypeface_FreeType::getFaceRec() const {
f_t_mutex().assertHeld();
fFTFaceOnce([this]{ fFaceRec = SkTypeface_FreeType::FaceRec::Make(this); });
return fFaceRec.get();
}
std::unique_ptr<SkFontData> SkTypeface_FreeType::makeFontData() const {
return this->onMakeFontData();
}
void SkTypeface_FreeType::FontDataPaletteToDescriptorPalette(const SkFontData& fontData,
SkFontDescriptor* desc) {
desc->setPaletteIndex(fontData.getPaletteIndex());
int paletteOverrideCount = fontData.getPaletteOverrideCount();
auto overrides = desc->setPaletteEntryOverrides(paletteOverrideCount);
for (int i = 0; i < paletteOverrideCount; ++i) {
overrides[i] = fontData.getPaletteOverrides()[i];
}
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
SkTypeface_FreeType::Scanner::Scanner() : fLibrary(nullptr) {
if (FT_New_Library(&gFTMemory, &fLibrary)) {
return;
}
FT_Add_Default_Modules(fLibrary);
FT_Set_Default_Properties(fLibrary);
}
SkTypeface_FreeType::Scanner::~Scanner() {
if (fLibrary) {
FT_Done_Library(fLibrary);
}
}
FT_Face SkTypeface_FreeType::Scanner::openFace(SkStreamAsset* stream, int ttcIndex,
FT_Stream ftStream) const
{
if (fLibrary == nullptr || stream == nullptr) {
return nullptr;
}
FT_Open_Args args;
memset(&args, 0, sizeof(args));
const void* memoryBase = stream->getMemoryBase();
if (memoryBase) {
args.flags = FT_OPEN_MEMORY;
args.memory_base = (const FT_Byte*)memoryBase;
args.memory_size = stream->getLength();
} else {
memset(ftStream, 0, sizeof(*ftStream));
ftStream->size = stream->getLength();
ftStream->descriptor.pointer = stream;
ftStream->read = sk_ft_stream_io;
ftStream->close = sk_ft_stream_close;
args.flags = FT_OPEN_STREAM;
args.stream = ftStream;
}
FT_Face face;
if (FT_Open_Face(fLibrary, &args, ttcIndex, &face)) {
return nullptr;
}
return face;
}
bool SkTypeface_FreeType::Scanner::recognizedFont(SkStreamAsset* stream, int* numFaces) const {
SkAutoMutexExclusive libraryLock(fLibraryMutex);
FT_StreamRec streamRec;
SkUniqueFTFace face(this->openFace(stream, -1, &streamRec));
if (!face) {
return false;
}
*numFaces = face->num_faces;
return true;
}
bool SkTypeface_FreeType::Scanner::scanFont(
SkStreamAsset* stream, int ttcIndex,
SkString* name, SkFontStyle* style, bool* isFixedPitch, AxisDefinitions* axes) const
{
SkAutoMutexExclusive libraryLock(fLibraryMutex);
FT_StreamRec streamRec;
SkUniqueFTFace face(this->openFace(stream, ttcIndex, &streamRec));
if (!face) {
return false;
}
int weight = SkFontStyle::kNormal_Weight;
int width = SkFontStyle::kNormal_Width;
SkFontStyle::Slant slant = SkFontStyle::kUpright_Slant;
if (face->style_flags & FT_STYLE_FLAG_BOLD) {
weight = SkFontStyle::kBold_Weight;
}
if (face->style_flags & FT_STYLE_FLAG_ITALIC) {
slant = SkFontStyle::kItalic_Slant;
}
bool hasAxes = face->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS;
TT_OS2* os2 = static_cast<TT_OS2*>(FT_Get_Sfnt_Table(face.get(), ft_sfnt_os2));
bool hasOs2 = os2 && os2->version != 0xffff;
PS_FontInfoRec psFontInfo;
if (hasOs2) {
weight = os2->usWeightClass;
width = os2->usWidthClass;
// OS/2::fsSelection bit 9 indicates oblique.
if (SkToBool(os2->fsSelection & (1u << 9))) {
slant = SkFontStyle::kOblique_Slant;
}
}
// Let variable axes override properties from the OS/2 table.
if (hasAxes) {
AxisDefinitions axisDefinitions;
if (GetAxes(face.get(), &axisDefinitions)) {
size_t numAxes = axisDefinitions.size();
static constexpr SkFourByteTag wghtTag = SkSetFourByteTag('w', 'g', 'h', 't');
static constexpr SkFourByteTag wdthTag = SkSetFourByteTag('w', 'd', 't', 'h');
static constexpr SkFourByteTag slntTag = SkSetFourByteTag('s', 'l', 'n', 't');
std::optional<size_t> wghtIndex;
std::optional<size_t> wdthIndex;
std::optional<size_t> slntIndex;
for(size_t i = 0; i < numAxes; ++i) {
if (axisDefinitions[i].fTag == wghtTag) {
// Rough validity check, is there sufficient spread and are ranges
// within 0-1000.
int wghtRange = SkFixedToScalar(axisDefinitions[i].fMaximum) -
SkFixedToScalar(axisDefinitions[i].fMinimum);
if (wghtRange > 5 && wghtRange <= 1000 &&
SkFixedToScalar(axisDefinitions[i].fMaximum) <= 1000) {
wghtIndex = i;
}
}
if (axisDefinitions[i].fTag == wdthTag) {
// Rough validity check, is there a spread and are ranges within
// 0-500.
int widthRange = SkFixedToScalar(axisDefinitions[i].fMaximum) -
SkFixedToScalar(axisDefinitions[i].fMinimum);
if (widthRange > 0 && widthRange <= 500 &&
SkFixedToScalar(axisDefinitions[i].fMaximum) <= 500)
wdthIndex = i;
}
if (axisDefinitions[i].fTag == slntTag)
slntIndex = i;
}
SkAutoSTMalloc<4, FT_Fixed> coords(numAxes);
if ((wghtIndex || wdthIndex || slntIndex) &&
!FT_Get_Var_Design_Coordinates(face.get(), numAxes, coords.get())) {
if (wghtIndex) {
SkASSERT(*wghtIndex < numAxes);
weight = SkScalarRoundToInt(SkFixedToScalar(coords[*wghtIndex]));
}
if (wdthIndex) {
SkASSERT(*wdthIndex < numAxes);
SkScalar wdthValue = SkFixedToScalar(coords[*wdthIndex]);
width = SkFontDescriptor::SkFontStyleWidthForWidthAxisValue(wdthValue);
}
if (slntIndex) {
SkASSERT(*slntIndex < numAxes);
// https://docs.microsoft.com/en-us/typography/opentype/spec/dvaraxistag_slnt
// "Scale interpretation: Values can be interpreted as the angle,
// in counter-clockwise degrees, of oblique slant from whatever
// the designer considers to be upright for that font design."
if (SkFixedToScalar(coords[*slntIndex]) < 0) {
slant = SkFontStyle::kOblique_Slant;
}
}
}
}
}
if (!hasOs2 && !hasAxes && 0 == FT_Get_PS_Font_Info(face.get(), &psFontInfo) && psFontInfo.weight) {
static const struct {
char const * const name;
int const weight;
} commonWeights [] = {
// There are probably more common names, but these are known to exist.
{ "all", SkFontStyle::kNormal_Weight }, // Multiple Masters usually default to normal.
{ "black", SkFontStyle::kBlack_Weight },
{ "bold", SkFontStyle::kBold_Weight },
{ "book", (SkFontStyle::kNormal_Weight + SkFontStyle::kLight_Weight)/2 },
{ "demi", SkFontStyle::kSemiBold_Weight },
{ "demibold", SkFontStyle::kSemiBold_Weight },
{ "extra", SkFontStyle::kExtraBold_Weight },
{ "extrabold", SkFontStyle::kExtraBold_Weight },
{ "extralight", SkFontStyle::kExtraLight_Weight },
{ "hairline", SkFontStyle::kThin_Weight },
{ "heavy", SkFontStyle::kBlack_Weight },
{ "light", SkFontStyle::kLight_Weight },
{ "medium", SkFontStyle::kMedium_Weight },
{ "normal", SkFontStyle::kNormal_Weight },
{ "plain", SkFontStyle::kNormal_Weight },
{ "regular", SkFontStyle::kNormal_Weight },
{ "roman", SkFontStyle::kNormal_Weight },
{ "semibold", SkFontStyle::kSemiBold_Weight },
{ "standard", SkFontStyle::kNormal_Weight },
{ "thin", SkFontStyle::kThin_Weight },
{ "ultra", SkFontStyle::kExtraBold_Weight },
{ "ultrablack", SkFontStyle::kExtraBlack_Weight },
{ "ultrabold", SkFontStyle::kExtraBold_Weight },
{ "ultraheavy", SkFontStyle::kExtraBlack_Weight },
{ "ultralight", SkFontStyle::kExtraLight_Weight },
};
int const index = SkStrLCSearch(&commonWeights[0].name, std::size(commonWeights),
psFontInfo.weight, sizeof(commonWeights[0]));
if (index >= 0) {
weight = commonWeights[index].weight;
} else {
LOG_INFO("Do not know weight for: %s (%s) \n", face->family_name, psFontInfo.weight);
}
}
if (name != nullptr) {
name->set(face->family_name);
}
if (style != nullptr) {
*style = SkFontStyle(weight, width, slant);
}
if (isFixedPitch != nullptr) {
*isFixedPitch = FT_IS_FIXED_WIDTH(face);
}
if (axes != nullptr && !GetAxes(face.get(), axes)) {
return false;
}
return true;
}
bool SkTypeface_FreeType::Scanner::GetAxes(FT_Face face, AxisDefinitions* axes) {
SkASSERT(face && axes);
if (face->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS) {
FT_MM_Var* variations = nullptr;
FT_Error err = FT_Get_MM_Var(face, &variations);
if (err) {
LOG_INFO("INFO: font %s claims to have variations, but none found.\n",
face->family_name);
return false;
}
SkAutoFree autoFreeVariations(variations);
axes->reset(variations->num_axis);
for (FT_UInt i = 0; i < variations->num_axis; ++i) {
const FT_Var_Axis& ftAxis = variations->axis[i];
(*axes)[i].fTag = ftAxis.tag;
(*axes)[i].fMinimum = ftAxis.minimum;
(*axes)[i].fDefault = ftAxis.def;
(*axes)[i].fMaximum = ftAxis.maximum;
}
}
return true;
}
/*static*/ void SkTypeface_FreeType::Scanner::computeAxisValues(
AxisDefinitions axisDefinitions,
const SkFontArguments::VariationPosition position,
SkFixed* axisValues,
const SkString& name,
const SkFontArguments::VariationPosition::Coordinate* current)
{
for (int i = 0; i < axisDefinitions.size(); ++i) {
const Scanner::AxisDefinition& axisDefinition = axisDefinitions[i];
const SkScalar axisMin = SkFixedToScalar(axisDefinition.fMinimum);
const SkScalar axisMax = SkFixedToScalar(axisDefinition.fMaximum);
// Start with the default value.
axisValues[i] = axisDefinition.fDefault;
// Then the current value.
if (current) {
for (int j = 0; j < axisDefinitions.size(); ++j) {
const auto& coordinate = current[j];
if (axisDefinition.fTag == coordinate.axis) {
const SkScalar axisValue = SkTPin(coordinate.value, axisMin, axisMax);
axisValues[i] = SkScalarToFixed(axisValue);
break;
}
}
}
// Then the requested value.
// The position may be over specified. If there are multiple values for a given axis,
// use the last one since that's what css-fonts-4 requires.
for (int j = position.coordinateCount; j --> 0;) {
const auto& coordinate = position.coordinates[j];
if (axisDefinition.fTag == coordinate.axis) {
const SkScalar axisValue = SkTPin(coordinate.value, axisMin, axisMax);
if (coordinate.value != axisValue) {
LOG_INFO("Requested font axis value out of range: "
"%s '%c%c%c%c' %f; pinned to %f.\n",
name.c_str(),
(axisDefinition.fTag >> 24) & 0xFF,
(axisDefinition.fTag >> 16) & 0xFF,
(axisDefinition.fTag >> 8) & 0xFF,
(axisDefinition.fTag ) & 0xFF,
SkScalarToDouble(coordinate.value),
SkScalarToDouble(axisValue));
}
axisValues[i] = SkScalarToFixed(axisValue);
break;
}
}
// TODO: warn on defaulted axis?
}
SkDEBUGCODE(
// Check for axis specified, but not matched in font.
for (int i = 0; i < position.coordinateCount; ++i) {
SkFourByteTag skTag = position.coordinates[i].axis;
bool found = false;
for (int j = 0; j < axisDefinitions.size(); ++j) {
if (skTag == axisDefinitions[j].fTag) {
found = true;
break;
}
}
if (!found) {
LOG_INFO("Requested font axis not found: %s '%c%c%c%c'\n",
name.c_str(),
(skTag >> 24) & 0xFF,
(skTag >> 16) & 0xFF,
(skTag >> 8) & 0xFF,
(skTag) & 0xFF);
}
}
)
}