firefox-main/gfx/thebes/gfxFontUtils.h (file symbol)

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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef GFX_FONT_UTILS_H
#define GFX_FONT_UTILS_H
#include "gfxPlatform.h"
#include "harfbuzz/hb.h"
#include "mozilla/Attributes.h"
#include "mozilla/EndianUtils.h"
#include "nsStringFwd.h"
#include "nsTArray.h"
#include "nscore.h"
class PickleIterator;
class gfxFontEntry;
struct gfxFontVariationAxis;
struct gfxFontVariationInstance;
class gfxSparseBitSet;
namespace mozilla {
class Encoding;
class ServoStyleSet;
class SlantStyleRange;
class StretchRange;
class WeightRange;
struct StyleFontStyle;
struct StyleFontStretch;
struct StyleFontWeight;
} // namespace mozilla
/* Bug 341128 - w32api defines min/max which causes problems with <bitset> */
#ifdef __MINGW32__
# undef min
# undef max
#endif
#undef ERROR /* defined by Windows.h, conflicts with some generated bindings \
code when this gets indirectly included via shared font list \
*/
typedef struct hb_blob_t hb_blob_t;
#define TRUETYPE_TAG(a, b, c, d) ((a) << 24 | (b) << 16 | (c) << 8 | (d))
namespace mozilla {
// Byte-swapping types and name table structure definitions moved from
// gfxFontUtils.cpp to .h file so that gfxFont.cpp can also refer to them
#pragma pack(1)
struct AutoSwap_PRUint16 {
#ifdef __SUNPRO_CC
AutoSwap_PRUint16& operator=(const uint16_t aValue) {
this->value = mozilla::NativeEndian::swapToBigEndian(aValue);
return *this;
}
#else
MOZ_IMPLICIT AutoSwap_PRUint16(uint16_t aValue) {
value = mozilla::NativeEndian::swapToBigEndian(aValue);
}
#endif
operator uint16_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
operator uint32_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
operator uint64_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
private:
uint16_t value;
};
struct AutoSwap_PRInt16 {
#ifdef __SUNPRO_CC
AutoSwap_PRInt16& operator=(const int16_t aValue) {
this->value = mozilla::NativeEndian::swapToBigEndian(aValue);
return *this;
}
#else
MOZ_IMPLICIT AutoSwap_PRInt16(int16_t aValue) {
value = mozilla::NativeEndian::swapToBigEndian(aValue);
}
#endif
operator int16_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
operator uint32_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
private:
int16_t value;
};
struct AutoSwap_PRUint32 {
#ifdef __SUNPRO_CC
AutoSwap_PRUint32& operator=(const uint32_t aValue) {
this->value = mozilla::NativeEndian::swapToBigEndian(aValue);
return *this;
}
#else
MOZ_IMPLICIT AutoSwap_PRUint32(uint32_t aValue) {
value = mozilla::NativeEndian::swapToBigEndian(aValue);
}
#endif
operator uint32_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
private:
uint32_t value;
};
struct AutoSwap_PRInt32 {
#ifdef __SUNPRO_CC
AutoSwap_PRInt32& operator=(const int32_t aValue) {
this->value = mozilla::NativeEndian::swapToBigEndian(aValue);
return *this;
}
#else
MOZ_IMPLICIT AutoSwap_PRInt32(int32_t aValue) {
value = mozilla::NativeEndian::swapToBigEndian(aValue);
}
#endif
operator int32_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
private:
int32_t value;
};
struct AutoSwap_PRUint64 {
#ifdef __SUNPRO_CC
AutoSwap_PRUint64& operator=(const uint64_t aValue) {
this->value = mozilla::NativeEndian::swapToBigEndian(aValue);
return *this;
}
#else
MOZ_IMPLICIT AutoSwap_PRUint64(uint64_t aValue) {
value = mozilla::NativeEndian::swapToBigEndian(aValue);
}
#endif
operator uint64_t() const {
return mozilla::NativeEndian::swapFromBigEndian(value);
}
private:
uint64_t value;
};
struct AutoSwap_PRUint24 {
operator uint32_t() const {
return value[0] << 16 | value[1] << 8 | value[2];
}
private:
AutoSwap_PRUint24() = default;
uint8_t value[3];
};
struct SFNTHeader {
AutoSwap_PRUint32 sfntVersion; // Fixed, 0x00010000 for version 1.0.
AutoSwap_PRUint16 numTables; // Number of tables.
AutoSwap_PRUint16 searchRange; // (Maximum power of 2 <= numTables) x 16.
AutoSwap_PRUint16 entrySelector; // Log2(maximum power of 2 <= numTables).
AutoSwap_PRUint16 rangeShift; // NumTables x 16-searchRange.
};
struct TTCHeader {
AutoSwap_PRUint32 ttcTag; // 4 -byte identifier 'ttcf'.
AutoSwap_PRUint16 majorVersion;
AutoSwap_PRUint16 minorVersion;
AutoSwap_PRUint32 numFonts;
// followed by:
// AutoSwap_PRUint32 offsetTable[numFonts]
};
struct TableDirEntry {
AutoSwap_PRUint32 tag; // 4 -byte identifier.
AutoSwap_PRUint32 checkSum; // CheckSum for this table.
AutoSwap_PRUint32 offset; // Offset from beginning of TrueType font file.
AutoSwap_PRUint32 length; // Length of this table.
};
struct HeadTable {
enum {
HEAD_VERSION = 0x00010000,
HEAD_MAGIC_NUMBER = 0x5F0F3CF5,
HEAD_CHECKSUM_CALC_CONST = 0xB1B0AFBA
};
AutoSwap_PRUint32 tableVersionNumber; // Fixed, 0x00010000 for version 1.0.
AutoSwap_PRUint32 fontRevision; // Set by font manufacturer.
AutoSwap_PRUint32
checkSumAdjustment; // To compute: set it to 0, sum the entire font as
// ULONG, then store 0xB1B0AFBA - sum.
AutoSwap_PRUint32 magicNumber; // Set to 0x5F0F3CF5.
AutoSwap_PRUint16 flags;
AutoSwap_PRUint16
unitsPerEm; // Valid range is from 16 to 16384. This value should be a
// power of 2 for fonts that have TrueType outlines.
AutoSwap_PRUint64 created; // Number of seconds since 12:00 midnight, January
// 1, 1904. 64-bit integer
AutoSwap_PRUint64 modified; // Number of seconds since 12:00 midnight,
// January 1, 1904. 64-bit integer
AutoSwap_PRInt16 xMin; // For all glyph bounding boxes.
AutoSwap_PRInt16 yMin; // For all glyph bounding boxes.
AutoSwap_PRInt16 xMax; // For all glyph bounding boxes.
AutoSwap_PRInt16 yMax; // For all glyph bounding boxes.
AutoSwap_PRUint16 macStyle; // Bit 0: Bold (if set to 1);
AutoSwap_PRUint16 lowestRecPPEM; // Smallest readable size in pixels.
AutoSwap_PRInt16 fontDirectionHint;
AutoSwap_PRInt16 indexToLocFormat;
AutoSwap_PRInt16 glyphDataFormat;
};
struct OS2Table {
AutoSwap_PRUint16 version; // 0004 = OpenType 1.5
AutoSwap_PRInt16 xAvgCharWidth;
AutoSwap_PRUint16 usWeightClass;
AutoSwap_PRUint16 usWidthClass;
AutoSwap_PRUint16 fsType;
AutoSwap_PRInt16 ySubscriptXSize;
AutoSwap_PRInt16 ySubscriptYSize;
AutoSwap_PRInt16 ySubscriptXOffset;
AutoSwap_PRInt16 ySubscriptYOffset;
AutoSwap_PRInt16 ySuperscriptXSize;
AutoSwap_PRInt16 ySuperscriptYSize;
AutoSwap_PRInt16 ySuperscriptXOffset;
AutoSwap_PRInt16 ySuperscriptYOffset;
AutoSwap_PRInt16 yStrikeoutSize;
AutoSwap_PRInt16 yStrikeoutPosition;
AutoSwap_PRInt16 sFamilyClass;
uint8_t panose[10];
AutoSwap_PRUint32 unicodeRange1;
AutoSwap_PRUint32 unicodeRange2;
AutoSwap_PRUint32 unicodeRange3;
AutoSwap_PRUint32 unicodeRange4;
uint8_t achVendID[4];
AutoSwap_PRUint16 fsSelection;
AutoSwap_PRUint16 usFirstCharIndex;
AutoSwap_PRUint16 usLastCharIndex;
AutoSwap_PRInt16 sTypoAscender;
AutoSwap_PRInt16 sTypoDescender;
AutoSwap_PRInt16 sTypoLineGap;
AutoSwap_PRUint16 usWinAscent;
AutoSwap_PRUint16 usWinDescent;
AutoSwap_PRUint32 codePageRange1;
AutoSwap_PRUint32 codePageRange2;
AutoSwap_PRInt16 sxHeight;
AutoSwap_PRInt16 sCapHeight;
AutoSwap_PRUint16 usDefaultChar;
AutoSwap_PRUint16 usBreakChar;
AutoSwap_PRUint16 usMaxContext;
};
struct PostTable {
AutoSwap_PRUint32 version;
AutoSwap_PRInt32 italicAngle;
AutoSwap_PRInt16 underlinePosition;
AutoSwap_PRUint16 underlineThickness;
AutoSwap_PRUint32 isFixedPitch;
AutoSwap_PRUint32 minMemType42;
AutoSwap_PRUint32 maxMemType42;
AutoSwap_PRUint32 minMemType1;
AutoSwap_PRUint32 maxMemType1;
};
// This structure is used for both 'hhea' and 'vhea' tables.
// The field names here are those of the horizontal version; the
// vertical table just exchanges vertical and horizontal coordinates.
struct MetricsHeader {
AutoSwap_PRUint32 version;
AutoSwap_PRInt16 ascender;
AutoSwap_PRInt16 descender;
AutoSwap_PRInt16 lineGap;
AutoSwap_PRUint16 advanceWidthMax;
AutoSwap_PRInt16 minLeftSideBearing;
AutoSwap_PRInt16 minRightSideBearing;
AutoSwap_PRInt16 xMaxExtent;
AutoSwap_PRInt16 caretSlopeRise;
AutoSwap_PRInt16 caretSlopeRun;
AutoSwap_PRInt16 caretOffset;
AutoSwap_PRInt16 reserved1;
AutoSwap_PRInt16 reserved2;
AutoSwap_PRInt16 reserved3;
AutoSwap_PRInt16 reserved4;
AutoSwap_PRInt16 metricDataFormat;
AutoSwap_PRUint16 numOfLongMetrics;
};
struct MaxpTableHeader {
AutoSwap_PRUint32 version; // CFF: 0x00005000; TrueType: 0x00010000
AutoSwap_PRUint16 numGlyphs;
// truetype version has additional fields that we don't currently use
};
// old 'kern' table, supported on Windows
struct KernTableVersion0 {
AutoSwap_PRUint16 version; // 0x0000
AutoSwap_PRUint16 nTables;
};
struct KernTableSubtableHeaderVersion0 {
AutoSwap_PRUint16 version;
AutoSwap_PRUint16 length;
AutoSwap_PRUint16 coverage;
};
// newer Mac-only 'kern' table, ignored by Windows
struct KernTableVersion1 {
AutoSwap_PRUint32 version; // 0x00010000
AutoSwap_PRUint32 nTables;
};
struct KernTableSubtableHeaderVersion1 {
AutoSwap_PRUint32 length;
AutoSwap_PRUint16 coverage;
AutoSwap_PRUint16 tupleIndex;
};
#pragma pack()
// Return just the highest bit of the given value, i.e., the highest
// power of 2 that is <= value, or zero if the input value is zero.
inline uint32_t FindHighestBit(uint32_t value) {
// propagate highest bit into all lower bits of the value
value |= (value >> 1);
value |= (value >> 2);
value |= (value >> 4);
value |= (value >> 8);
value |= (value >> 16);
// isolate the leftmost bit
return (value & ~(value >> 1));
}
} // namespace mozilla
// used for overlaying name changes without touching original font data
struct FontDataOverlay {
// overlaySrc != 0 ==> use overlay
uint32_t overlaySrc; // src offset from start of font data
uint32_t overlaySrcLen; // src length
uint32_t overlayDest; // dest offset from start of font data
};
enum gfxUserFontType {
GFX_USERFONT_UNKNOWN = 0,
GFX_USERFONT_OPENTYPE = 1,
GFX_USERFONT_SVG = 2,
GFX_USERFONT_WOFF = 3,
GFX_USERFONT_WOFF2 = 4
};
extern const uint8_t sCJKCompatSVSTable[];
class gfxFontUtils {
public:
// these are public because gfxFont.cpp also looks into the name table
enum {
NAME_ID_FAMILY = 1,
NAME_ID_STYLE = 2,
NAME_ID_UNIQUE = 3,
NAME_ID_FULL = 4,
NAME_ID_VERSION = 5,
NAME_ID_POSTSCRIPT = 6,
NAME_ID_PREFERRED_FAMILY = 16,
NAME_ID_PREFERRED_STYLE = 17,
PLATFORM_ALL = -1,
PLATFORM_ID_UNICODE = 0, // Mac OS uses this typically
PLATFORM_ID_MAC = 1,
PLATFORM_ID_ISO = 2,
PLATFORM_ID_MICROSOFT = 3,
ENCODING_ID_MAC_ROMAN = 0, // traditional Mac OS script manager encodings
ENCODING_ID_MAC_JAPANESE =
1, // (there are others defined, but some were never
ENCODING_ID_MAC_TRAD_CHINESE =
2, // implemented by Apple, and I have never seen them
ENCODING_ID_MAC_KOREAN = 3, // used in font names)
ENCODING_ID_MAC_ARABIC = 4,
ENCODING_ID_MAC_HEBREW = 5,
ENCODING_ID_MAC_GREEK = 6,
ENCODING_ID_MAC_CYRILLIC = 7,
ENCODING_ID_MAC_DEVANAGARI = 9,
ENCODING_ID_MAC_GURMUKHI = 10,
ENCODING_ID_MAC_GUJARATI = 11,
ENCODING_ID_MAC_SIMP_CHINESE = 25,
ENCODING_ID_MICROSOFT_SYMBOL = 0, // Microsoft platform encoding IDs
ENCODING_ID_MICROSOFT_UNICODEBMP = 1,
ENCODING_ID_MICROSOFT_SHIFTJIS = 2,
ENCODING_ID_MICROSOFT_PRC = 3,
ENCODING_ID_MICROSOFT_BIG5 = 4,
ENCODING_ID_MICROSOFT_WANSUNG = 5,
ENCODING_ID_MICROSOFT_JOHAB = 6,
ENCODING_ID_MICROSOFT_UNICODEFULL = 10,
LANG_ALL = -1,
LANG_ID_MAC_ENGLISH = 0, // many others are defined, but most don't affect
LANG_ID_MAC_HEBREW =
10, // the charset; should check all the central/eastern
LANG_ID_MAC_JAPANESE = 11, // european codes, though
LANG_ID_MAC_ARABIC = 12,
LANG_ID_MAC_ICELANDIC = 15,
LANG_ID_MAC_TURKISH = 17,
LANG_ID_MAC_TRAD_CHINESE = 19,
LANG_ID_MAC_URDU = 20,
LANG_ID_MAC_KOREAN = 23,
LANG_ID_MAC_POLISH = 25,
LANG_ID_MAC_FARSI = 31,
LANG_ID_MAC_SIMP_CHINESE = 33,
LANG_ID_MAC_ROMANIAN = 37,
LANG_ID_MAC_CZECH = 38,
LANG_ID_MAC_SLOVAK = 39,
LANG_ID_MICROSOFT_EN_US =
0x0409, // with Microsoft platformID, EN US lang code
CMAP_MAX_CODEPOINT = 0x10ffff // maximum possible Unicode codepoint
// contained in a cmap
};
// name table has a header, followed by name records, followed by string data
struct NameHeader {
mozilla::AutoSwap_PRUint16 format; // Format selector (=0).
mozilla::AutoSwap_PRUint16 count; // Number of name records.
mozilla::AutoSwap_PRUint16 stringOffset; // Offset to start of string
// storage (from start of table)
};
struct NameRecord {
mozilla::AutoSwap_PRUint16 platformID; // Platform ID
mozilla::AutoSwap_PRUint16 encodingID; // Platform-specific encoding ID
mozilla::AutoSwap_PRUint16 languageID; // Language ID
mozilla::AutoSwap_PRUint16 nameID; // Name ID.
mozilla::AutoSwap_PRUint16 length; // String length (in bytes).
mozilla::AutoSwap_PRUint16 offset; // String offset from start of storage
// (in bytes).
};
// Helper to ensure we free a font table when we return.
class AutoHBBlob {
public:
explicit AutoHBBlob(hb_blob_t* aBlob) : mBlob(aBlob) {}
~AutoHBBlob() { hb_blob_destroy(mBlob); }
operator hb_blob_t*() { return mBlob; }
private:
hb_blob_t* const mBlob;
};
// for reading big-endian font data on either big or little-endian platforms
static inline uint16_t ReadShortAt(const uint8_t* aBuf, uint32_t aIndex) {
return static_cast<uint16_t>(aBuf[aIndex] << 8) | aBuf[aIndex + 1];
}
static inline uint16_t ReadShortAt16(const uint16_t* aBuf, uint32_t aIndex) {
const uint8_t* buf = reinterpret_cast<const uint8_t*>(aBuf);
uint32_t index = aIndex << 1;
return static_cast<uint16_t>(buf[index] << 8) | buf[index + 1];
}
static inline uint32_t ReadUint24At(const uint8_t* aBuf, uint32_t aIndex) {
return ((aBuf[aIndex] << 16) | (aBuf[aIndex + 1] << 8) |
(aBuf[aIndex + 2]));
}
static inline uint32_t ReadLongAt(const uint8_t* aBuf, uint32_t aIndex) {
return ((aBuf[aIndex] << 24) | (aBuf[aIndex + 1] << 16) |
(aBuf[aIndex + 2] << 8) | (aBuf[aIndex + 3]));
}
static nsresult ReadCMAPTableFormat10(const uint8_t* aBuf, uint32_t aLength,
gfxSparseBitSet& aCharacterMap);
static nsresult ReadCMAPTableFormat12or13(const uint8_t* aBuf,
uint32_t aLength,
gfxSparseBitSet& aCharacterMap);
static nsresult ReadCMAPTableFormat4(const uint8_t* aBuf, uint32_t aLength,
gfxSparseBitSet& aCharacterMap,
bool aIsSymbolFont);
static nsresult ReadCMAPTableFormat14(const uint8_t* aBuf, uint32_t aLength,
const uint8_t*& aTable);
static uint32_t FindPreferredSubtable(const uint8_t* aBuf,
uint32_t aBufLength,
uint32_t* aTableOffset,
uint32_t* aUVSTableOffset,
bool* aIsSymbolFont);
static nsresult ReadCMAP(const uint8_t* aBuf, uint32_t aBufLength,
gfxSparseBitSet& aCharacterMap,
uint32_t& aUVSOffset);
static uint32_t MapCharToGlyphFormat4(const uint8_t* aBuf, uint32_t aLength,
char16_t aCh);
static uint32_t MapCharToGlyphFormat10(const uint8_t* aBuf, uint32_t aCh);
static uint32_t MapCharToGlyphFormat12or13(const uint8_t* aBuf, uint32_t aCh);
static uint16_t MapUVSToGlyphFormat14(const uint8_t* aBuf, uint32_t aCh,
uint32_t aVS);
// Return whether <aCh, aVS> is supported as the default variation for aCh.
static bool IsDefaultUVSSequence(const uint8_t* aBuf, uint32_t aCh,
uint32_t aVS);
// sCJKCompatSVSTable is a 'cmap' format 14 subtable that maps
// <char + var-selector> pairs to the corresponding Unicode
// compatibility ideograph codepoints.
static MOZ_ALWAYS_INLINE uint32_t GetUVSFallback(uint32_t aCh, uint32_t aVS) {
aCh = MapUVSToGlyphFormat14(sCJKCompatSVSTable, aCh, aVS);
return aCh >= 0xFB00 ? aCh + (0x2F800 - 0xFB00) : aCh;
}
static uint32_t MapCharToGlyph(const uint8_t* aCmapBuf, uint32_t aBufLength,
uint32_t aUnicode, uint32_t aVarSelector = 0);
// For legacy MS Symbol fonts, we try mapping 8-bit character codes to the
// Private Use range at U+F0xx used by the cmaps in these fonts.
static MOZ_ALWAYS_INLINE uint32_t MapLegacySymbolFontCharToPUA(uint32_t aCh) {
return aCh >= 0x20 && aCh <= 0xff ? 0xf000 + aCh : 0;
}
#ifdef XP_WIN
// determine whether a font (which has already been sanitized, so is known
// to be a valid sfnt) is CFF format rather than TrueType
static bool IsCffFont(const uint8_t* aFontData);
#endif
// determine the format of font data
static gfxUserFontType DetermineFontDataType(const uint8_t* aFontData,
uint32_t aFontDataLength);
// Read the fullname from the sfnt data (used to save the original name
// prior to renaming the font for installation).
// This is called with sfnt data that has already been validated,
// so it should always succeed in finding the name table.
static nsresult GetFullNameFromSFNT(const uint8_t* aFontData,
uint32_t aLength, nsACString& aFullName);
// helper to get fullname from name table, constructing from family+style
// if no explicit fullname is present
static nsresult GetFullNameFromTable(hb_blob_t* aNameTable,
nsACString& aFullName);
// helper to get family name from name table
static nsresult GetFamilyNameFromTable(hb_blob_t* aNameTable,
nsACString& aFamilyName);
// Find the table directory entry for a given table tag, in a (validated)
// buffer of 'sfnt' data. Returns null if the tag is not present.
static mozilla::TableDirEntry* FindTableDirEntry(const void* aFontData,
uint32_t aTableTag);
// Return a blob that wraps a table found within a buffer of font data.
// The blob does NOT own its data; caller guarantees that the buffer
// will remain valid at least as long as the blob.
// Returns null if the specified table is not found.
// This method assumes aFontData is valid 'sfnt' data; before using this,
// caller is responsible to do any sanitization/validation necessary.
static hb_blob_t* GetTableFromFontData(const void* aFontData,
uint32_t aTableTag);
// create a new name table and build a new font with that name table
// appended on the end, returns true on success
static nsresult RenameFont(const nsAString& aName, const uint8_t* aFontData,
uint32_t aFontDataLength,
FallibleTArray<uint8_t>* aNewFont);
// read all names matching aNameID, returning in aNames array
static nsresult ReadNames(const char* aNameData, uint32_t aDataLen,
uint32_t aNameID, int32_t aPlatformID,
nsTArray<nsCString>& aNames);
// reads English or first name matching aNameID, returning in aName
// platform based on OS
static nsresult ReadCanonicalName(hb_blob_t* aNameTable, uint32_t aNameID,
nsCString& aName);
static nsresult ReadCanonicalName(const char* aNameData, uint32_t aDataLen,
uint32_t aNameID, nsCString& aName);
// convert a name from the raw name table data into an nsString,
// provided we know how; return true if successful, or false
// if we can't handle the encoding
static bool DecodeFontName(const char* aBuf, int32_t aLength,
uint32_t aPlatformCode, uint32_t aScriptCode,
uint32_t aLangCode, nsACString& dest);
static inline bool IsJoinCauser(uint32_t ch) { return (ch == 0x200D); }
// We treat Combining Grapheme Joiner (U+034F) together with the join
// controls (ZWJ, ZWNJ) here, because (like them) it is an invisible
// char that will be handled by the shaper even if not explicitly
// supported by the font. (See bug 1408366.)
static inline bool IsJoinControl(uint32_t ch) {
return (ch == 0x200C || ch == 0x200D || ch == 0x034f);
}
enum {
kUnicodeVS1 = 0xFE00,
kUnicodeVS16 = 0xFE0F,
kUnicodeVS17 = 0xE0100,
kUnicodeVS256 = 0xE01EF
};
static inline bool IsVarSelector(uint32_t ch) {
return (ch >= kUnicodeVS1 && ch <= kUnicodeVS16) ||
(ch >= kUnicodeVS17 && ch <= kUnicodeVS256);
}
enum {
kUnicodeRegionalIndicatorA = 0x1F1E6,
kUnicodeRegionalIndicatorZ = 0x1F1FF
};
static inline bool IsRegionalIndicator(uint32_t aCh) {
return aCh >= kUnicodeRegionalIndicatorA &&
aCh <= kUnicodeRegionalIndicatorZ;
}
static inline bool IsEmojiFlagAndTag(uint32_t aCh, uint32_t aNext) {
constexpr uint32_t kBlackFlag = 0x1F3F4;
constexpr uint32_t kTagLetterA = 0xE0061;
constexpr uint32_t kTagLetterZ = 0xE007A;
return aCh == kBlackFlag && aNext >= kTagLetterA && aNext <= kTagLetterZ;
}
// parse a simple list of font family names into
// an array of strings
static void ParseFontList(const nsACString& aFamilyList,
nsTArray<nsCString>& aFontList);
// for a given pref name, initialize a list of font names
static void GetPrefsFontList(const char* aPrefName,
nsTArray<nsCString>& aFontList);
// generate a unique font name
static nsresult MakeUniqueUserFontName(nsAString& aName);
// Helper used to implement gfxFontEntry::GetVariation{Axes,Instances} for
// platforms where the native font APIs don't provide the info we want
// in a convenient form, or when native APIs are too expensive.
// (Not used on platforms -- currently, freetype -- where the font APIs
// expose variation instance details directly.)
static void GetVariationData(gfxFontEntry* aFontEntry,
nsTArray<gfxFontVariationAxis>* aAxes,
nsTArray<gfxFontVariationInstance>* aInstances);
// Helper method for reading localized family names from the name table
// of a single face.
static void ReadOtherFamilyNamesForFace(
const nsACString& aFamilyName, const char* aNameData,
uint32_t aDataLength, nsTArray<nsCString>& aOtherFamilyNames,
bool useFullName);
// Main, DOM worker or servo thread safe method to check if we are performing
// Servo traversal.
static bool IsInServoTraversal();
// Main, DOM worker or servo thread safe method to get the current
// ServoTypeSet. Always returns nullptr for DOM worker threads.
static mozilla::ServoStyleSet* CurrentServoStyleSet();
static void AssertSafeThreadOrServoFontMetricsLocked()
#ifdef DEBUG
;
#else
{
}
#endif
protected:
friend struct MacCharsetMappingComparator;
static nsresult ReadNames(const char* aNameData, uint32_t aDataLen,
uint32_t aNameID, int32_t aLangID,
int32_t aPlatformID, nsTArray<nsCString>& aNames);
// convert opentype name-table platform/encoding/language values to an
// Encoding object we can use to convert the name data to unicode
static const mozilla::Encoding* GetCharsetForFontName(uint16_t aPlatform,
uint16_t aScript,
uint16_t aLanguage);
struct MacFontNameCharsetMapping {
uint16_t mScript;
uint16_t mLanguage;
const mozilla::Encoding* mEncoding;
bool operator<(const MacFontNameCharsetMapping& rhs) const {
return (mScript < rhs.mScript) ||
((mScript == rhs.mScript) && (mLanguage < rhs.mLanguage));
}
};
static const MacFontNameCharsetMapping gMacFontNameCharsets[];
static const mozilla::Encoding* gISOFontNameCharsets[];
static const mozilla::Encoding* gMSFontNameCharsets[];
};
// Factors used to weight the distances between the available and target font
// properties during font-matching. These ensure that we respect the CSS-fonts
// requirement that font-stretch >> font-style >> font-weight; and in addition,
// a mismatch between the desired and actual glyph presentation (emoji vs text)
// will take precedence over any of the style attributes.
constexpr double kPresentationMismatch = 1.0e12;
constexpr double kStretchFactor = 1.0e8;
constexpr double kStyleFactor = 1.0e4;
constexpr double kWeightFactor = 1.0e0;
// If the output range of this function is extended, check assertions &
// usage at the callsites!
// style distance ==> [0,900]
double StyleDistance(const mozilla::SlantStyleRange& aRange,
const mozilla::StyleFontStyle& aTargetStyle,
bool aItalicToObliqueFallback);
// stretch distance ==> [0,2000]
double StretchDistance(const mozilla::StretchRange& aRange,
const mozilla::StyleFontStretch& aTargetStretch);
// weight distance ==> [0,1600]
double WeightDistance(const mozilla::WeightRange& aRange,
const mozilla::StyleFontWeight& aTargetWeight);
#endif /* GFX_FONT_UTILS_H */