The Tor Browser: gfx/thebes/gfxCoreTextShaper.cpp@b8a032363ba2 (annotated)

gfx/thebes/gfxCoreTextShaper.cpp@b8a032363ba2 (annotated)

gfx/thebes/gfxCoreTextShaper.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  * 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/. */
 #include "mozilla/ArrayUtils.h"
 #include "gfxCoreTextShaper.h"
 #include "gfxMacFont.h"
 #include "gfxFontUtils.h"
 #include "mozilla/gfx/2D.h"
 #include <algorithm>
 using namespace mozilla;
 // standard font descriptors that we construct the first time they're needed
 CTFontDescriptorRef gfxCoreTextShaper::sDefaultFeaturesDescriptor = nullptr;
 CTFontDescriptorRef gfxCoreTextShaper::sDisableLigaturesDescriptor = nullptr;
 gfxCoreTextShaper::gfxCoreTextShaper(gfxMacFont *aFont)
     : gfxFontShaper(aFont)
 {
     // Create our CTFontRef
     mCTFont = ::CTFontCreateWithGraphicsFont(aFont->GetCGFontRef(),
                                              aFont->GetAdjustedSize(),
                                              nullptr,
                                              GetDefaultFeaturesDescriptor());
     // Set up the default attribute dictionary that we will need each time we create a CFAttributedString
     mAttributesDict = ::CFDictionaryCreate(kCFAllocatorDefault,
                                            (const void**) &kCTFontAttributeName,
                                            (const void**) &mCTFont,
 , // count of attributes
                                            &kCFTypeDictionaryKeyCallBacks,
                                            &kCFTypeDictionaryValueCallBacks);
 }
 gfxCoreTextShaper::~gfxCoreTextShaper()
 {
     if (mAttributesDict) {
         ::CFRelease(mAttributesDict);
     }
     if (mCTFont) {
         ::CFRelease(mCTFont);
     }
 }
 bool
 gfxCoreTextShaper::ShapeText(gfxContext      *aContext,
                              const char16_t *aText,
                              uint32_t         aOffset,
                              uint32_t         aLength,
                              int32_t          aScript,
                              gfxShapedText   *aShapedText)
 {
     // Create a CFAttributedString with text and style info, so we can use CoreText to lay it out.
     bool isRightToLeft = aShapedText->IsRightToLeft();
     uint32_t length = aLength;
     // we need to bidi-wrap the text if the run is RTL,
     // or if it is an LTR run but may contain (overridden) RTL chars
     bool bidiWrap = isRightToLeft;
     if (!bidiWrap && !aShapedText->TextIs8Bit()) {
         uint32_t i;
         for (i = 0; i < length; ++i) {
             if (gfxFontUtils::PotentialRTLChar(aText[i])) {
                 bidiWrap = true;
                 break;
             }
         }
     }
     // If there's a possibility of any bidi, we wrap the text with direction overrides
     // to ensure neutrals or characters that were bidi-overridden in HTML behave properly.
     const UniChar beginLTR[]    = { 0x202d, 0x20 };
     const UniChar beginRTL[]    = { 0x202e, 0x20 };
     const UniChar endBidiWrap[] = { 0x20, 0x2e, 0x202c };
     uint32_t startOffset;
     CFStringRef stringObj;
     if (bidiWrap) {
         startOffset = isRightToLeft ?
             mozilla::ArrayLength(beginRTL) : mozilla::ArrayLength(beginLTR);
         CFMutableStringRef mutableString =
             ::CFStringCreateMutable(kCFAllocatorDefault,
                                     length + startOffset + mozilla::ArrayLength(endBidiWrap));
         ::CFStringAppendCharacters(mutableString,
                                    isRightToLeft ? beginRTL : beginLTR,
                                    startOffset);
         ::CFStringAppendCharacters(mutableString, reinterpret_cast<const UniChar*>(aText), length);
         ::CFStringAppendCharacters(mutableString,
                                    endBidiWrap, mozilla::ArrayLength(endBidiWrap));
         stringObj = mutableString;
     } else {
         startOffset = 0;
         stringObj = ::CFStringCreateWithCharactersNoCopy(kCFAllocatorDefault,
                                                          reinterpret_cast<const UniChar*>(aText),
                                                          length, kCFAllocatorNull);
     }
     CFDictionaryRef attrObj;
     if (aShapedText->DisableLigatures()) {
         // For letterspacing (or maybe other situations) we need to make a copy of the CTFont
         // with the ligature feature disabled
         CTFontRef ctFont =
             CreateCTFontWithDisabledLigatures(::CTFontGetSize(mCTFont));
         attrObj =
             ::CFDictionaryCreate(kCFAllocatorDefault,
                                  (const void**) &kCTFontAttributeName,
                                  (const void**) &ctFont,
 , // count of attributes
                                  &kCFTypeDictionaryKeyCallBacks,
                                  &kCFTypeDictionaryValueCallBacks);
         // Having created the dict, we're finished with our ligature-disabled CTFontRef
         ::CFRelease(ctFont);
     } else {
         attrObj = mAttributesDict;
         ::CFRetain(attrObj);
     }
     // Now we can create an attributed string
     CFAttributedStringRef attrStringObj =
         ::CFAttributedStringCreate(kCFAllocatorDefault, stringObj, attrObj);
     ::CFRelease(stringObj);
     ::CFRelease(attrObj);
     // Create the CoreText line from our string, then we're done with it
     CTLineRef line = ::CTLineCreateWithAttributedString(attrStringObj);
     ::CFRelease(attrStringObj);
     // and finally retrieve the glyph data and store into the gfxTextRun
     CFArrayRef glyphRuns = ::CTLineGetGlyphRuns(line);
     uint32_t numRuns = ::CFArrayGetCount(glyphRuns);
     // Iterate through the glyph runs.
     // Note that this includes the bidi wrapper, so we have to be careful
     // not to include the extra glyphs from there
     bool success = true;
     for (uint32_t runIndex = 0; runIndex < numRuns; runIndex++) {
         CTRunRef aCTRun =
             (CTRunRef)::CFArrayGetValueAtIndex(glyphRuns, runIndex);
         if (SetGlyphsFromRun(aShapedText, aOffset, aLength, aCTRun, startOffset) != NS_OK) {
             success = false;
             break;
         }
     }
     ::CFRelease(line);
     return success;
 }
 #define SMALL_GLYPH_RUN 128 // preallocated size of our auto arrays for per-glyph data;
                             // some testing indicates that 90%+ of glyph runs will fit
                             // without requiring a separate allocation
 nsresult
 gfxCoreTextShaper::SetGlyphsFromRun(gfxShapedText *aShapedText,
                                     uint32_t       aOffset,
                                     uint32_t       aLength,
                                     CTRunRef       aCTRun,
                                     int32_t        aStringOffset)
 {
     // The word has been bidi-wrapped; aStringOffset is the number
     // of chars at the beginning of the CTLine that we should skip.
     // aCTRun is a glyph run from the CoreText layout process.
     int32_t direction = aShapedText->IsRightToLeft() ? -1 : 1;
     int32_t numGlyphs = ::CTRunGetGlyphCount(aCTRun);
     if (numGlyphs == 0) {
         return NS_OK;
     }
     int32_t wordLength = aLength;
     // character offsets get really confusing here, as we have to keep track of
     // (a) the text in the actual textRun we're constructing
     // (c) the string that was handed to CoreText, which contains the text of the font run
     //     plus directional-override padding
     // (d) the CTRun currently being processed, which may be a sub-run of the CoreText line
     //     (but may extend beyond the actual font run into the bidi wrapping text).
     //     aStringOffset tells us how many initial characters of the line to ignore.
     // get the source string range within the CTLine's text
     CFRange stringRange = ::CTRunGetStringRange(aCTRun);
     // skip the run if it is entirely outside the actual range of the font run
     if (stringRange.location - aStringOffset + stringRange.length <= 0 ||
         stringRange.location - aStringOffset >= wordLength) {
         return NS_OK;
     }
     // retrieve the laid-out glyph data from the CTRun
     nsAutoArrayPtr<CGGlyph> glyphsArray;
     nsAutoArrayPtr<CGPoint> positionsArray;
     nsAutoArrayPtr<CFIndex> glyphToCharArray;
     const CGGlyph* glyphs = nullptr;
     const CGPoint* positions = nullptr;
     const CFIndex* glyphToChar = nullptr;
     // Testing indicates that CTRunGetGlyphsPtr (almost?) always succeeds,
     // and so allocating a new array and copying data with CTRunGetGlyphs
     // will be extremely rare.
     // If this were not the case, we could use an nsAutoTArray<> to
     // try and avoid the heap allocation for small runs.
     // It's possible that some future change to CoreText will mean that
     // CTRunGetGlyphsPtr fails more often; if this happens, nsAutoTArray<>
     // may become an attractive option.
     glyphs = ::CTRunGetGlyphsPtr(aCTRun);
     if (!glyphs) {
         glyphsArray = new (std::nothrow) CGGlyph[numGlyphs];
         if (!glyphsArray) {
             return NS_ERROR_OUT_OF_MEMORY;
         }
         ::CTRunGetGlyphs(aCTRun, ::CFRangeMake(0, 0), glyphsArray.get());
         glyphs = glyphsArray.get();
     }
     positions = ::CTRunGetPositionsPtr(aCTRun);
     if (!positions) {
         positionsArray = new (std::nothrow) CGPoint[numGlyphs];
         if (!positionsArray) {
             return NS_ERROR_OUT_OF_MEMORY;
         }
         ::CTRunGetPositions(aCTRun, ::CFRangeMake(0, 0), positionsArray.get());
         positions = positionsArray.get();
     }
     // Remember that the glyphToChar indices relate to the CoreText line,
     // not to the beginning of the textRun, the font run,
     // or the stringRange of the glyph run
     glyphToChar = ::CTRunGetStringIndicesPtr(aCTRun);
     if (!glyphToChar) {
         glyphToCharArray = new (std::nothrow) CFIndex[numGlyphs];
         if (!glyphToCharArray) {
             return NS_ERROR_OUT_OF_MEMORY;
         }
         ::CTRunGetStringIndices(aCTRun, ::CFRangeMake(0, 0), glyphToCharArray.get());
         glyphToChar = glyphToCharArray.get();
     }
     double runWidth = ::CTRunGetTypographicBounds(aCTRun, ::CFRangeMake(0, 0),
                                                   nullptr, nullptr, nullptr);
     nsAutoTArray<gfxShapedText::DetailedGlyph,1> detailedGlyphs;
     gfxShapedText::CompressedGlyph g;
     gfxShapedText::CompressedGlyph *charGlyphs =
         aShapedText->GetCharacterGlyphs() + aOffset;
     // CoreText gives us the glyphindex-to-charindex mapping, which relates each glyph
     // to a source text character; we also need the charindex-to-glyphindex mapping to
     // find the glyph for a given char. Note that some chars may not map to any glyph
     // (ligature continuations), and some may map to several glyphs (eg Indic split vowels).
     // We set the glyph index to NO_GLYPH for chars that have no associated glyph, and we
     // record the last glyph index for cases where the char maps to several glyphs,
     // so that our clumping will include all the glyph fragments for the character.
     // The charToGlyph array is indexed by char position within the stringRange of the glyph run.
     static const int32_t NO_GLYPH = -1;
     AutoFallibleTArray<int32_t,SMALL_GLYPH_RUN> charToGlyphArray;
     if (!charToGlyphArray.SetLength(stringRange.length)) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
     int32_t *charToGlyph = charToGlyphArray.Elements();
     for (int32_t offset = 0; offset < stringRange.length; ++offset) {
         charToGlyph[offset] = NO_GLYPH;
     }
     for (int32_t i = 0; i < numGlyphs; ++i) {
         int32_t loc = glyphToChar[i] - stringRange.location;
         if (loc >= 0 && loc < stringRange.length) {
             charToGlyph[loc] = i;
         }
     }
     // Find character and glyph clumps that correspond, allowing for ligatures,
     // indic reordering, split glyphs, etc.
     //
     // The idea is that we'll find a character sequence starting at the first char of stringRange,
     // and extend it until it includes the character associated with the first glyph;
     // we also extend it as long as there are "holes" in the range of glyphs. So we
     // will eventually have a contiguous sequence of characters, starting at the beginning
     // of the range, that map to a contiguous sequence of glyphs, starting at the beginning
     // of the glyph array. That's a clump; then we update the starting positions and repeat.
     //
     // NB: In the case of RTL layouts, we iterate over the stringRange in reverse.
     //
     // This may find characters that fall outside the range 0:wordLength,
     // so we won't necessarily use everything we find here.
     bool isRightToLeft = aShapedText->IsRightToLeft();
     int32_t glyphStart = 0; // looking for a clump that starts at this glyph index
     int32_t charStart = isRightToLeft ?
         stringRange.length - 1 : 0; // and this char index (in the stringRange of the glyph run)
     while (glyphStart < numGlyphs) { // keep finding groups until all glyphs are accounted for
         bool inOrder = true;
         int32_t charEnd = glyphToChar[glyphStart] - stringRange.location;
         NS_WARN_IF_FALSE(charEnd >= 0 && charEnd < stringRange.length,
                          "glyph-to-char mapping points outside string range");
         // clamp charEnd to the valid range of the string
         charEnd = std::max(charEnd, 0);
         charEnd = std::min(charEnd, int32_t(stringRange.length));
         int32_t glyphEnd = glyphStart;
         int32_t charLimit = isRightToLeft ? -1 : stringRange.length;
         do {
             // This is normally executed once for each iteration of the outer loop,
             // but in unusual cases where the character/glyph association is complex,
             // the initial character range might correspond to a non-contiguous
             // glyph range with "holes" in it. If so, we will repeat this loop to
             // extend the character range until we have a contiguous glyph sequence.
             NS_ASSERTION((direction > 0 && charEnd < charLimit) ||
                          (direction < 0 && charEnd > charLimit),
                          "no characters left in range?");
             charEnd += direction;
             while (charEnd != charLimit && charToGlyph[charEnd] == NO_GLYPH) {
                 charEnd += direction;
             }
             // find the maximum glyph index covered by the clump so far
             if (isRightToLeft) {
                 for (int32_t i = charStart; i > charEnd; --i) {
                     if (charToGlyph[i] != NO_GLYPH) {
                         // update extent of glyph range
                         glyphEnd = std::max(glyphEnd, charToGlyph[i] + 1);
                     }
                 }
             } else {
                 for (int32_t i = charStart; i < charEnd; ++i) {
                     if (charToGlyph[i] != NO_GLYPH) {
                         // update extent of glyph range
                         glyphEnd = std::max(glyphEnd, charToGlyph[i] + 1);
                     }
                 }
             }
             if (glyphEnd == glyphStart + 1) {
                 // for the common case of a single-glyph clump, we can skip the following checks
                 break;
             }
             if (glyphEnd == glyphStart) {
                 // no glyphs, try to extend the clump
                 continue;
             }
             // check whether all glyphs in the range are associated with the characters
             // in our clump; if not, we have a discontinuous range, and should extend it
             // unless we've reached the end of the text
             bool allGlyphsAreWithinCluster = true;
             int32_t prevGlyphCharIndex = charStart;
             for (int32_t i = glyphStart; i < glyphEnd; ++i) {
                 int32_t glyphCharIndex = glyphToChar[i] - stringRange.location;
                 if (isRightToLeft) {
                     if (glyphCharIndex > charStart || glyphCharIndex <= charEnd) {
                         allGlyphsAreWithinCluster = false;
                         break;
                     }
                     if (glyphCharIndex > prevGlyphCharIndex) {
                         inOrder = false;
                     }
                     prevGlyphCharIndex = glyphCharIndex;
                 } else {
                     if (glyphCharIndex < charStart || glyphCharIndex >= charEnd) {
                         allGlyphsAreWithinCluster = false;
                         break;
                     }
                     if (glyphCharIndex < prevGlyphCharIndex) {
                         inOrder = false;
                     }
                     prevGlyphCharIndex = glyphCharIndex;
                 }
             }
             if (allGlyphsAreWithinCluster) {
                 break;
             }
         } while (charEnd != charLimit);
         NS_WARN_IF_FALSE(glyphStart < glyphEnd,
                          "character/glyph clump contains no glyphs!");
         if (glyphStart == glyphEnd) {
             ++glyphStart; // make progress - avoid potential infinite loop
             charStart = charEnd;
             continue;
         }
         NS_WARN_IF_FALSE(charStart != charEnd,
                          "character/glyph clump contains no characters!");
         if (charStart == charEnd) {
             glyphStart = glyphEnd; // this is bad - we'll discard the glyph(s),
                                    // as there's nowhere to attach them
             continue;
         }
         // Now charStart..charEnd is a ligature clump, corresponding to glyphStart..glyphEnd;
         // Set baseCharIndex to the char we'll actually attach the glyphs to (1st of ligature),
         // and endCharIndex to the limit (position beyond the last char),
         // adjusting for the offset of the stringRange relative to the textRun.
         int32_t baseCharIndex, endCharIndex;
         if (isRightToLeft) {
             while (charEnd >= 0 && charToGlyph[charEnd] == NO_GLYPH) {
                 charEnd--;
             }
             baseCharIndex = charEnd + stringRange.location - aStringOffset + 1;
             endCharIndex = charStart + stringRange.location - aStringOffset + 1;
         } else {
             while (charEnd < stringRange.length && charToGlyph[charEnd] == NO_GLYPH) {
                 charEnd++;
             }
             baseCharIndex = charStart + stringRange.location - aStringOffset;
             endCharIndex = charEnd + stringRange.location - aStringOffset;
         }
         // Then we check if the clump falls outside our actual string range; if so, just go to the next.
         if (endCharIndex <= 0 || baseCharIndex >= wordLength) {
             glyphStart = glyphEnd;
             charStart = charEnd;
             continue;
         }
         // Ensure we won't try to go beyond the valid length of the word's text
         baseCharIndex = std::max(baseCharIndex, 0);
         endCharIndex = std::min(endCharIndex, wordLength);
         // Now we're ready to set the glyph info in the textRun; measure the glyph width
         // of the first (perhaps only) glyph, to see if it is "Simple"
         int32_t appUnitsPerDevUnit = aShapedText->GetAppUnitsPerDevUnit();
         double toNextGlyph;
         if (glyphStart < numGlyphs-1) {
             toNextGlyph = positions[glyphStart+1].x - positions[glyphStart].x;
         } else {
             toNextGlyph = positions[0].x + runWidth - positions[glyphStart].x;
         }
         int32_t advance = int32_t(toNextGlyph * appUnitsPerDevUnit);
         // Check if it's a simple one-to-one mapping
         int32_t glyphsInClump = glyphEnd - glyphStart;
         if (glyphsInClump == 1 &&
             gfxTextRun::CompressedGlyph::IsSimpleGlyphID(glyphs[glyphStart]) &&
             gfxTextRun::CompressedGlyph::IsSimpleAdvance(advance) &&
             charGlyphs[baseCharIndex].IsClusterStart() &&
             positions[glyphStart].y == 0.0)
         {
             charGlyphs[baseCharIndex].SetSimpleGlyph(advance,
                                                      glyphs[glyphStart]);
         } else {
             // collect all glyphs in a list to be assigned to the first char;
             // there must be at least one in the clump, and we already measured its advance,
             // hence the placement of the loop-exit test and the measurement of the next glyph
             while (1) {
                 gfxTextRun::DetailedGlyph *details = detailedGlyphs.AppendElement();
                 details->mGlyphID = glyphs[glyphStart];
                 details->mXOffset = 0;
                 details->mYOffset = -positions[glyphStart].y * appUnitsPerDevUnit;
                 details->mAdvance = advance;
                 if (++glyphStart >= glyphEnd) {
                    break;
                 }
                 if (glyphStart < numGlyphs-1) {
                     toNextGlyph = positions[glyphStart+1].x - positions[glyphStart].x;
                 } else {
                     toNextGlyph = positions[0].x + runWidth - positions[glyphStart].x;
                 }
                 advance = int32_t(toNextGlyph * appUnitsPerDevUnit);
             }
             gfxTextRun::CompressedGlyph g;
             g.SetComplex(charGlyphs[baseCharIndex].IsClusterStart(),
                          true, detailedGlyphs.Length());
             aShapedText->SetGlyphs(aOffset + baseCharIndex, g, detailedGlyphs.Elements());
             detailedGlyphs.Clear();
         }
         // the rest of the chars in the group are ligature continuations, no associated glyphs
         while (++baseCharIndex != endCharIndex && baseCharIndex < wordLength) {
             gfxShapedText::CompressedGlyph &g = charGlyphs[baseCharIndex];
             NS_ASSERTION(!g.IsSimpleGlyph(), "overwriting a simple glyph");
             g.SetComplex(inOrder && g.IsClusterStart(), false, 0);
         }
         glyphStart = glyphEnd;
         charStart = charEnd;
     }
     return NS_OK;
 }
 #undef SMALL_GLYPH_RUN
 // Construct the font attribute descriptor that we'll apply by default when creating a CTFontRef.
 // This will turn off line-edge swashes by default, because we don't know the actual line breaks
 // when doing glyph shaping.
 void
 gfxCoreTextShaper::CreateDefaultFeaturesDescriptor()
 {
     if (sDefaultFeaturesDescriptor != nullptr) {
         return;
     }
     SInt16 val = kSmartSwashType;
     CFNumberRef swashesType =
         ::CFNumberCreate(kCFAllocatorDefault,
                          kCFNumberSInt16Type,
                          &val);
     val = kLineInitialSwashesOffSelector;
     CFNumberRef lineInitialsOffSelector =
         ::CFNumberCreate(kCFAllocatorDefault,
                          kCFNumberSInt16Type,
                          &val);
     CFTypeRef keys[]   = { kCTFontFeatureTypeIdentifierKey,
                            kCTFontFeatureSelectorIdentifierKey };
     CFTypeRef values[] = { swashesType,
                            lineInitialsOffSelector };
     CFDictionaryRef featureSettings[2];
     featureSettings[0] =
         ::CFDictionaryCreate(kCFAllocatorDefault,
                              (const void **) keys,
                              (const void **) values,
                              ArrayLength(keys),
                              &kCFTypeDictionaryKeyCallBacks,
                              &kCFTypeDictionaryValueCallBacks);
     ::CFRelease(lineInitialsOffSelector);
     val = kLineFinalSwashesOffSelector;
     CFNumberRef lineFinalsOffSelector =
         ::CFNumberCreate(kCFAllocatorDefault,
                          kCFNumberSInt16Type,
                          &val);
     values[1] = lineFinalsOffSelector;
     featureSettings[1] =
         ::CFDictionaryCreate(kCFAllocatorDefault,
                              (const void **) keys,
                              (const void **) values,
                              ArrayLength(keys),
                              &kCFTypeDictionaryKeyCallBacks,
                              &kCFTypeDictionaryValueCallBacks);
     ::CFRelease(lineFinalsOffSelector);
     ::CFRelease(swashesType);
     CFArrayRef featuresArray =
         ::CFArrayCreate(kCFAllocatorDefault,
                         (const void **) featureSettings,
                         ArrayLength(featureSettings),
                         &kCFTypeArrayCallBacks);
     ::CFRelease(featureSettings[0]);
     ::CFRelease(featureSettings[1]);
     const CFTypeRef attrKeys[]   = { kCTFontFeatureSettingsAttribute };
     const CFTypeRef attrValues[] = { featuresArray };
     CFDictionaryRef attributesDict =
         ::CFDictionaryCreate(kCFAllocatorDefault,
                              (const void **) attrKeys,
                              (const void **) attrValues,
                              ArrayLength(attrKeys),
                              &kCFTypeDictionaryKeyCallBacks,
                              &kCFTypeDictionaryValueCallBacks);
     ::CFRelease(featuresArray);
     sDefaultFeaturesDescriptor =
         ::CTFontDescriptorCreateWithAttributes(attributesDict);
     ::CFRelease(attributesDict);
 }
 // Create a CTFontRef, with the Common Ligatures feature disabled
 CTFontRef
 gfxCoreTextShaper::CreateCTFontWithDisabledLigatures(CGFloat aSize)
 {
     if (sDisableLigaturesDescriptor == nullptr) {
         // initialize cached descriptor to turn off the Common Ligatures feature
         SInt16 val = kLigaturesType;
         CFNumberRef ligaturesType =
             ::CFNumberCreate(kCFAllocatorDefault,
                              kCFNumberSInt16Type,
                              &val);
         val = kCommonLigaturesOffSelector;
         CFNumberRef commonLigaturesOffSelector =
             ::CFNumberCreate(kCFAllocatorDefault,
                              kCFNumberSInt16Type,
                              &val);
         const CFTypeRef keys[]   = { kCTFontFeatureTypeIdentifierKey,
                                      kCTFontFeatureSelectorIdentifierKey };
         const CFTypeRef values[] = { ligaturesType,
                                      commonLigaturesOffSelector };
         CFDictionaryRef featureSettingDict =
             ::CFDictionaryCreate(kCFAllocatorDefault,
                                  (const void **) keys,
                                  (const void **) values,
                                  ArrayLength(keys),
                                  &kCFTypeDictionaryKeyCallBacks,
                                  &kCFTypeDictionaryValueCallBacks);
         ::CFRelease(ligaturesType);
         ::CFRelease(commonLigaturesOffSelector);
         CFArrayRef featuresArray =
             ::CFArrayCreate(kCFAllocatorDefault,
                             (const void **) &featureSettingDict,
 ,
                             &kCFTypeArrayCallBacks);
         ::CFRelease(featureSettingDict);
         CFDictionaryRef attributesDict =
             ::CFDictionaryCreate(kCFAllocatorDefault,
                                  (const void **) &kCTFontFeatureSettingsAttribute,
                                  (const void **) &featuresArray,
 , // count of keys & values
                                  &kCFTypeDictionaryKeyCallBacks,
                                  &kCFTypeDictionaryValueCallBacks);
         ::CFRelease(featuresArray);
         sDisableLigaturesDescriptor =
             ::CTFontDescriptorCreateCopyWithAttributes(GetDefaultFeaturesDescriptor(),
                                                        attributesDict);
         ::CFRelease(attributesDict);
     }
     gfxMacFont *f = static_cast<gfxMacFont*>(mFont);
     return ::CTFontCreateWithGraphicsFont(f->GetCGFontRef(), aSize, nullptr,
                                           sDisableLigaturesDescriptor);
 }
 void
 gfxCoreTextShaper::Shutdown() // [static]
 {
     if (sDisableLigaturesDescriptor != nullptr) {
         ::CFRelease(sDisableLigaturesDescriptor);
         sDisableLigaturesDescriptor = nullptr;
     }
     if (sDefaultFeaturesDescriptor != nullptr) {
         ::CFRelease(sDefaultFeaturesDescriptor);
         sDefaultFeaturesDescriptor = nullptr;
     }
 }

The Tor Browser / annotate

gfx/thebes/gfxCoreTextShaper.cpp@b8a032363ba2 (annotated)

gfx/thebes/gfxCoreTextShaper.cpp