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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /gfx/thebes/gfxCoreTextShaper.cpp
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gfx/thebes/gfxCoreTextShaper.cpp')
-rw-r--r--gfx/thebes/gfxCoreTextShaper.cpp651
1 files changed, 651 insertions, 0 deletions
diff --git a/gfx/thebes/gfxCoreTextShaper.cpp b/gfx/thebes/gfxCoreTextShaper.cpp
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+++ b/gfx/thebes/gfxCoreTextShaper.cpp
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+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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 "gfxTextRun.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/ScaledFontMac.h"
+#include "mozilla/UniquePtrExtensions.h"
+
+#include <algorithm>
+
+#include <dlfcn.h>
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+
+// standard font descriptors that we construct the first time they're needed
+CTFontDescriptorRef gfxCoreTextShaper::sFeaturesDescriptor[kMaxFontInstances];
+
+// Helper to create a CFDictionary with the right attributes for shaping our
+// text, including imposing the given directionality.
+CFDictionaryRef gfxCoreTextShaper::CreateAttrDict(bool aRightToLeft) {
+ // Because we always shape unidirectional runs, and may have applied
+ // directional overrides, we want to force a direction rather than
+ // allowing CoreText to do its own unicode-based bidi processing.
+ SInt16 dirOverride = kCTWritingDirectionOverride |
+ (aRightToLeft ? kCTWritingDirectionRightToLeft
+ : kCTWritingDirectionLeftToRight);
+ CFNumberRef dirNumber =
+ ::CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt16Type, &dirOverride);
+ CFArrayRef dirArray = ::CFArrayCreate(
+ kCFAllocatorDefault, (const void**)&dirNumber, 1, &kCFTypeArrayCallBacks);
+ ::CFRelease(dirNumber);
+ CFTypeRef attrs[] = {kCTFontAttributeName, kCTWritingDirectionAttributeName};
+ CFTypeRef values[] = {mCTFont[0], dirArray};
+ CFDictionaryRef attrDict = ::CFDictionaryCreate(
+ kCFAllocatorDefault, attrs, values, ArrayLength(attrs),
+ &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
+ ::CFRelease(dirArray);
+ return attrDict;
+}
+
+gfxCoreTextShaper::gfxCoreTextShaper(gfxMacFont* aFont)
+ : gfxFontShaper(aFont),
+ mAttributesDictLTR(nullptr),
+ mAttributesDictRTL(nullptr) {
+ for (size_t i = 0; i < kMaxFontInstances; i++) {
+ mCTFont[i] = nullptr;
+ }
+ // Create our default CTFontRef
+ mCTFont[0] = CreateCTFontWithFeatures(
+ aFont->GetAdjustedSize(), GetFeaturesDescriptor(kDefaultFeatures));
+}
+
+gfxCoreTextShaper::~gfxCoreTextShaper() {
+ if (mAttributesDictLTR) {
+ ::CFRelease(mAttributesDictLTR);
+ }
+ if (mAttributesDictRTL) {
+ ::CFRelease(mAttributesDictRTL);
+ }
+ for (size_t i = 0; i < kMaxFontInstances; i++) {
+ if (mCTFont[i]) {
+ ::CFRelease(mCTFont[i]);
+ }
+ }
+}
+
+static bool IsBuggyIndicScript(intl::Script aScript) {
+ return aScript == intl::Script::BENGALI || aScript == intl::Script::KANNADA ||
+ aScript == intl::Script::ORIYA || aScript == intl::Script::KHMER;
+}
+
+bool gfxCoreTextShaper::ShapeText(DrawTarget* aDrawTarget,
+ const char16_t* aText, uint32_t aOffset,
+ uint32_t aLength, Script aScript,
+ nsAtom* aLanguage, bool aVertical,
+ RoundingFlags aRounding,
+ gfxShapedText* aShapedText) {
+ // Create a CFAttributedString with text and style info, so we can use
+ // CoreText to lay it out.
+ bool isRightToLeft = aShapedText->IsRightToLeft();
+ const UniChar* text = reinterpret_cast<const UniChar*>(aText);
+
+ CFStringRef stringObj = ::CFStringCreateWithCharactersNoCopy(
+ kCFAllocatorDefault, text, aLength, kCFAllocatorNull);
+
+ // Figure out whether we should try to set the AAT small-caps feature:
+ // examine OpenType tags for the requested style, and see if 'smcp' is
+ // among them.
+ const gfxFontStyle* style = mFont->GetStyle();
+ gfxFontEntry* entry = mFont->GetFontEntry();
+ auto handleFeatureTag = [](const uint32_t& aTag, uint32_t& aValue,
+ void* aUserArg) -> void {
+ if (aTag == HB_TAG('s', 'm', 'c', 'p') && aValue) {
+ *static_cast<bool*>(aUserArg) = true;
+ }
+ };
+ bool addSmallCaps = false;
+ MergeFontFeatures(style, entry->mFeatureSettings, false, entry->FamilyName(),
+ false, handleFeatureTag, &addSmallCaps);
+
+ // Get an attributes dictionary suitable for shaping text in the
+ // current direction, creating it if necessary.
+ CFDictionaryRef attrObj =
+ isRightToLeft ? mAttributesDictRTL : mAttributesDictLTR;
+ if (!attrObj) {
+ attrObj = CreateAttrDict(isRightToLeft);
+ (isRightToLeft ? mAttributesDictRTL : mAttributesDictLTR) = attrObj;
+ }
+
+ FeatureFlags featureFlags = kDefaultFeatures;
+ if (IsBuggyIndicScript(aScript)) {
+ // To work around buggy Indic AAT fonts shipped with OS X,
+ // we re-enable the Line Initial Smart Swashes feature that is needed
+ // for "split vowels" to work in at least Bengali and Kannada fonts.
+ // Affected fonts include Bangla MN, Bangla Sangam MN, Kannada MN,
+ // Kannada Sangam MN. See bugs 686225, 728557, 953231, 1145515.
+ // Also applies to Oriya and Khmer, see bug 1370927 and bug 1403166.
+ featureFlags |= kIndicFeatures;
+ }
+ if (aShapedText->DisableLigatures()) {
+ // For letterspacing (or maybe other situations) we need to make
+ // a copy of the CTFont with the ligature feature disabled.
+ featureFlags |= kDisableLigatures;
+ }
+ if (addSmallCaps) {
+ featureFlags |= kAddSmallCaps;
+ }
+
+ // For the disabled-ligature, buggy-indic-font or small-caps case, replace
+ // the default CTFont in the attribute dictionary with a tweaked version.
+ CFMutableDictionaryRef mutableAttr = nullptr;
+ if (featureFlags != 0) {
+ if (!mCTFont[featureFlags]) {
+ mCTFont[featureFlags] = CreateCTFontWithFeatures(
+ mFont->GetAdjustedSize(), GetFeaturesDescriptor(featureFlags));
+ }
+ mutableAttr =
+ ::CFDictionaryCreateMutableCopy(kCFAllocatorDefault, 2, attrObj);
+ ::CFDictionaryReplaceValue(mutableAttr, kCTFontAttributeName,
+ mCTFont[featureFlags]);
+ attrObj = mutableAttr;
+ }
+
+ // Now we can create an attributed string
+ CFAttributedStringRef attrStringObj =
+ ::CFAttributedStringCreate(kCFAllocatorDefault, stringObj, attrObj);
+ ::CFRelease(stringObj);
+
+ // 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.
+ bool success = true;
+ for (uint32_t runIndex = 0; runIndex < numRuns; runIndex++) {
+ CTRunRef aCTRun = (CTRunRef)::CFArrayGetValueAtIndex(glyphRuns, runIndex);
+ CFRange range = ::CTRunGetStringRange(aCTRun);
+ CFDictionaryRef runAttr = ::CTRunGetAttributes(aCTRun);
+ if (runAttr != attrObj) {
+ // If Core Text manufactured a new dictionary, this may indicate
+ // unexpected font substitution. In that case, we fail (and fall
+ // back to harfbuzz shaping)...
+ const void* font1 = ::CFDictionaryGetValue(attrObj, kCTFontAttributeName);
+ const void* font2 = ::CFDictionaryGetValue(runAttr, kCTFontAttributeName);
+ if (font1 != font2) {
+ // ...except that if the fallback was only for a variation
+ // selector or join control that is otherwise unsupported,
+ // we just ignore it.
+ if (range.length == 1) {
+ char16_t ch = aText[range.location];
+ if (gfxFontUtils::IsJoinControl(ch) ||
+ gfxFontUtils::IsVarSelector(ch)) {
+ continue;
+ }
+ }
+ NS_WARNING("unexpected font fallback in Core Text");
+ success = false;
+ break;
+ }
+ }
+ if (SetGlyphsFromRun(aShapedText, aOffset, aLength, aCTRun) != NS_OK) {
+ success = false;
+ break;
+ }
+ }
+
+ if (mutableAttr) {
+ ::CFRelease(mutableAttr);
+ }
+ ::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) {
+ typedef gfxShapedText::CompressedGlyph CompressedGlyph;
+
+ 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
+ // (d) the CTRun currently being processed, which may be a sub-run of the
+ // CoreText line
+
+ // 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 + stringRange.length <= 0 ||
+ stringRange.location >= wordLength) {
+ return NS_OK;
+ }
+
+ // retrieve the laid-out glyph data from the CTRun
+ UniquePtr<CGGlyph[]> glyphsArray;
+ UniquePtr<CGPoint[]> positionsArray;
+ UniquePtr<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 AutoTArray<> 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, AutoTArray<>
+ // may become an attractive option.
+ glyphs = ::CTRunGetGlyphsPtr(aCTRun);
+ if (!glyphs) {
+ glyphsArray = MakeUniqueFallible<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 = MakeUniqueFallible<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 = MakeUniqueFallible<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);
+
+ AutoTArray<gfxShapedText::DetailedGlyph, 1> detailedGlyphs;
+ 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;
+ AutoTArray<int32_t, SMALL_GLYPH_RUN> charToGlyphArray;
+ if (!charToGlyphArray.SetLength(stringRange.length, fallible)) {
+ 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_WARNING_ASSERTION(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_WARNING_ASSERTION(glyphStart < glyphEnd,
+ "character/glyph clump contains no glyphs!");
+ if (glyphStart == glyphEnd) {
+ ++glyphStart; // make progress - avoid potential infinite loop
+ charStart = charEnd;
+ continue;
+ }
+
+ NS_WARNING_ASSERTION(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 + 1;
+ endCharIndex = charStart + stringRange.location + 1;
+ } else {
+ while (charEnd < stringRange.length && charToGlyph[charEnd] == NO_GLYPH) {
+ charEnd++;
+ }
+ baseCharIndex = charStart + stringRange.location;
+ endCharIndex = charEnd + stringRange.location;
+ }
+
+ // 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 (true) {
+ gfxTextRun::DetailedGlyph* details = detailedGlyphs.AppendElement();
+ details->mGlyphID = glyphs[glyphStart];
+ details->mOffset.y = -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);
+ }
+
+ aShapedText->SetDetailedGlyphs(aOffset + baseCharIndex,
+ detailedGlyphs.Length(),
+ detailedGlyphs.Elements());
+
+ detailedGlyphs.Clear();
+ }
+
+ // the rest of the chars in the group are ligature continuations, no
+ // associated glyphs
+ while (++baseCharIndex != endCharIndex && baseCharIndex < wordLength) {
+ CompressedGlyph& shapedTextGlyph = charGlyphs[baseCharIndex];
+ NS_ASSERTION(!shapedTextGlyph.IsSimpleGlyph(),
+ "overwriting a simple glyph");
+ shapedTextGlyph.SetComplex(inOrder && shapedTextGlyph.IsClusterStart(),
+ false);
+ }
+
+ 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.
+
+// We also cache feature descriptors for shaping with disabled ligatures, and
+// for buggy Indic AAT font workarounds, created on an as-needed basis.
+
+#define MAX_FEATURES 5 // max used by any of our Get*Descriptor functions
+
+CTFontDescriptorRef gfxCoreTextShaper::CreateFontFeaturesDescriptor(
+ const std::pair<SInt16, SInt16>* aFeatures, size_t aCount) {
+ MOZ_ASSERT(aCount <= MAX_FEATURES);
+
+ CFDictionaryRef featureSettings[MAX_FEATURES];
+
+ for (size_t i = 0; i < aCount; i++) {
+ CFNumberRef type = ::CFNumberCreate(
+ kCFAllocatorDefault, kCFNumberSInt16Type, &aFeatures[i].first);
+ CFNumberRef selector = ::CFNumberCreate(
+ kCFAllocatorDefault, kCFNumberSInt16Type, &aFeatures[i].second);
+
+ CFTypeRef keys[] = {kCTFontFeatureTypeIdentifierKey,
+ kCTFontFeatureSelectorIdentifierKey};
+ CFTypeRef values[] = {type, selector};
+ featureSettings[i] = ::CFDictionaryCreate(
+ kCFAllocatorDefault, (const void**)keys, (const void**)values,
+ ArrayLength(keys), &kCFTypeDictionaryKeyCallBacks,
+ &kCFTypeDictionaryValueCallBacks);
+
+ ::CFRelease(selector);
+ ::CFRelease(type);
+ }
+
+ CFArrayRef featuresArray =
+ ::CFArrayCreate(kCFAllocatorDefault, (const void**)featureSettings,
+ aCount, // not ArrayLength(featureSettings), as we
+ // may not have used all the allocated slots
+ &kCFTypeArrayCallBacks);
+
+ for (size_t i = 0; i < aCount; i++) {
+ ::CFRelease(featureSettings[i]);
+ }
+
+ const CFTypeRef attrKeys[] = {kCTFontFeatureSettingsAttribute};
+ const CFTypeRef attrValues[] = {featuresArray};
+ CFDictionaryRef attributesDict = ::CFDictionaryCreate(
+ kCFAllocatorDefault, (const void**)attrKeys, (const void**)attrValues,
+ ArrayLength(attrKeys), &kCFTypeDictionaryKeyCallBacks,
+ &kCFTypeDictionaryValueCallBacks);
+ ::CFRelease(featuresArray);
+
+ CTFontDescriptorRef descriptor =
+ ::CTFontDescriptorCreateWithAttributes(attributesDict);
+ ::CFRelease(attributesDict);
+
+ return descriptor;
+}
+
+CTFontDescriptorRef gfxCoreTextShaper::GetFeaturesDescriptor(
+ FeatureFlags aFeatureFlags) {
+ MOZ_ASSERT(aFeatureFlags < kMaxFontInstances);
+ if (!sFeaturesDescriptor[aFeatureFlags]) {
+ typedef std::pair<SInt16, SInt16> FeatT;
+ AutoTArray<FeatT, MAX_FEATURES> features;
+ features.AppendElement(
+ FeatT(kSmartSwashType, kLineFinalSwashesOffSelector));
+ if ((aFeatureFlags & kIndicFeatures) == 0) {
+ features.AppendElement(
+ FeatT(kSmartSwashType, kLineInitialSwashesOffSelector));
+ }
+ if (aFeatureFlags & kAddSmallCaps) {
+ features.AppendElement(FeatT(kLetterCaseType, kSmallCapsSelector));
+ features.AppendElement(
+ FeatT(kLowerCaseType, kLowerCaseSmallCapsSelector));
+ }
+ if (aFeatureFlags & kDisableLigatures) {
+ features.AppendElement(
+ FeatT(kLigaturesType, kCommonLigaturesOffSelector));
+ }
+ MOZ_ASSERT(features.Length() <= MAX_FEATURES);
+ sFeaturesDescriptor[aFeatureFlags] =
+ CreateFontFeaturesDescriptor(features.Elements(), features.Length());
+ }
+ return sFeaturesDescriptor[aFeatureFlags];
+}
+
+CTFontRef gfxCoreTextShaper::CreateCTFontWithFeatures(
+ CGFloat aSize, CTFontDescriptorRef aDescriptor) {
+ const gfxFontEntry* fe = mFont->GetFontEntry();
+ bool isInstalledFont = !fe->IsUserFont() || fe->IsLocalUserFont();
+ CGFontRef cgFont = static_cast<gfxMacFont*>(mFont)->GetCGFontRef();
+ return CreateCTFontFromCGFontWithVariations(cgFont, aSize, isInstalledFont,
+ aDescriptor);
+}
+
+void gfxCoreTextShaper::Shutdown() // [static]
+{
+ for (size_t i = 0; i < kMaxFontInstances; i++) {
+ if (sFeaturesDescriptor[i] != nullptr) {
+ ::CFRelease(sFeaturesDescriptor[i]);
+ sFeaturesDescriptor[i] = nullptr;
+ }
+ }
+}