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gecko-dev/gfx/thebes/gfxFont.cpp
Nicholas Nethercote 3493a38202 Bug 1232822 (part 6) - Move RefCairo() from gfxContext to gfxFont. r=jfkthame. 
Because gfxContext will one day disappear, and gfxFont seems like a good place
to move it to.
2015-12-15 20:10:04 -08:00

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/* -*- 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 "gfxFont.h"
#include "mozilla/BinarySearch.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/Logging.h"
#include "nsExpirationTracker.h"
#include "nsITimer.h"
#include "gfxGlyphExtents.h"
#include "gfxPlatform.h"
#include "gfxTextRun.h"
#include "nsGkAtoms.h"
#include "gfxTypes.h"
#include "gfxContext.h"
#include "gfxFontMissingGlyphs.h"
#include "gfxGraphiteShaper.h"
#include "gfxHarfBuzzShaper.h"
#include "gfxUserFontSet.h"
#include "nsSpecialCasingData.h"
#include "nsTextRunTransformations.h"
#include "nsUnicodeProperties.h"
#include "nsStyleConsts.h"
#include "mozilla/AppUnits.h"
#include "mozilla/Likely.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Preferences.h"
#include "mozilla/Services.h"
#include "mozilla/Telemetry.h"
#include "gfxSVGGlyphs.h"
#include "gfx2DGlue.h"
#include "GreekCasing.h"
#include "cairo.h"
#include "harfbuzz/hb.h"
#include "harfbuzz/hb-ot.h"
#include "graphite2/Font.h"
#include <algorithm>
#include <limits>
#include <cmath>
using namespace mozilla;
using namespace mozilla::gfx;
using namespace mozilla::unicode;
using mozilla::services::GetObserverService;
gfxFontCache *gfxFontCache::gGlobalCache = nullptr;
#ifdef DEBUG_roc
#define DEBUG_TEXT_RUN_STORAGE_METRICS
#endif
#ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
uint32_t gTextRunStorageHighWaterMark = 0;
uint32_t gTextRunStorage = 0;
uint32_t gFontCount = 0;
uint32_t gGlyphExtentsCount = 0;
uint32_t gGlyphExtentsWidthsTotalSize = 0;
uint32_t gGlyphExtentsSetupEagerSimple = 0;
uint32_t gGlyphExtentsSetupEagerTight = 0;
uint32_t gGlyphExtentsSetupLazyTight = 0;
uint32_t gGlyphExtentsSetupFallBackToTight = 0;
#endif
#define LOG_FONTINIT(args) MOZ_LOG(gfxPlatform::GetLog(eGfxLog_fontinit), \
LogLevel::Debug, args)
#define LOG_FONTINIT_ENABLED() MOZ_LOG_TEST( \
gfxPlatform::GetLog(eGfxLog_fontinit), \
LogLevel::Debug)
/*
* gfxFontCache - global cache of gfxFont instances.
* Expires unused fonts after a short interval;
* notifies fonts to age their cached shaped-word records;
* observes memory-pressure notification and tells fonts to clear their
* shaped-word caches to free up memory.
*/
MOZ_DEFINE_MALLOC_SIZE_OF(FontCacheMallocSizeOf)
NS_IMPL_ISUPPORTS(gfxFontCache::MemoryReporter, nsIMemoryReporter)
NS_IMETHODIMP
gfxFontCache::MemoryReporter::CollectReports(
nsIMemoryReporterCallback* aCb, nsISupports* aClosure, bool aAnonymize)
{
FontCacheSizes sizes;
gfxFontCache::GetCache()->AddSizeOfIncludingThis(&FontCacheMallocSizeOf,
&sizes);
aCb->Callback(EmptyCString(),
NS_LITERAL_CSTRING("explicit/gfx/font-cache"),
KIND_HEAP, UNITS_BYTES, sizes.mFontInstances,
NS_LITERAL_CSTRING("Memory used for active font instances."),
aClosure);
aCb->Callback(EmptyCString(),
NS_LITERAL_CSTRING("explicit/gfx/font-shaped-words"),
KIND_HEAP, UNITS_BYTES, sizes.mShapedWords,
NS_LITERAL_CSTRING("Memory used to cache shaped glyph data."),
aClosure);
return NS_OK;
}
NS_IMPL_ISUPPORTS(gfxFontCache::Observer, nsIObserver)
NS_IMETHODIMP
gfxFontCache::Observer::Observe(nsISupports *aSubject,
const char *aTopic,
const char16_t *someData)
{
if (!nsCRT::strcmp(aTopic, "memory-pressure")) {
gfxFontCache *fontCache = gfxFontCache::GetCache();
if (fontCache) {
fontCache->FlushShapedWordCaches();
}
} else {
NS_NOTREACHED("unexpected notification topic");
}
return NS_OK;
}
nsresult
gfxFontCache::Init()
{
NS_ASSERTION(!gGlobalCache, "Where did this come from?");
gGlobalCache = new gfxFontCache();
if (!gGlobalCache) {
return NS_ERROR_OUT_OF_MEMORY;
}
RegisterStrongMemoryReporter(new MemoryReporter());
return NS_OK;
}
void
gfxFontCache::Shutdown()
{
delete gGlobalCache;
gGlobalCache = nullptr;
#ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
printf("Textrun storage high water mark=%d\n", gTextRunStorageHighWaterMark);
printf("Total number of fonts=%d\n", gFontCount);
printf("Total glyph extents allocated=%d (size %d)\n", gGlyphExtentsCount,
int(gGlyphExtentsCount*sizeof(gfxGlyphExtents)));
printf("Total glyph extents width-storage size allocated=%d\n", gGlyphExtentsWidthsTotalSize);
printf("Number of simple glyph extents eagerly requested=%d\n", gGlyphExtentsSetupEagerSimple);
printf("Number of tight glyph extents eagerly requested=%d\n", gGlyphExtentsSetupEagerTight);
printf("Number of tight glyph extents lazily requested=%d\n", gGlyphExtentsSetupLazyTight);
printf("Number of simple glyph extent setups that fell back to tight=%d\n", gGlyphExtentsSetupFallBackToTight);
#endif
}
gfxFontCache::gfxFontCache()
: nsExpirationTracker<gfxFont,3>(FONT_TIMEOUT_SECONDS * 1000,
"gfxFontCache")
{
nsCOMPtr<nsIObserverService> obs = GetObserverService();
if (obs) {
obs->AddObserver(new Observer, "memory-pressure", false);
}
#ifndef RELEASE_BUILD
// Currently disabled for release builds, due to unexplained crashes
// during expiration; see bug 717175 & 894798.
mWordCacheExpirationTimer = do_CreateInstance("@mozilla.org/timer;1");
if (mWordCacheExpirationTimer) {
mWordCacheExpirationTimer->
InitWithFuncCallback(WordCacheExpirationTimerCallback, this,
SHAPED_WORD_TIMEOUT_SECONDS * 1000,
nsITimer::TYPE_REPEATING_SLACK);
}
#endif
}
gfxFontCache::~gfxFontCache()
{
// Ensure the user font cache releases its references to font entries,
// so they aren't kept alive after the font instances and font-list
// have been shut down.
gfxUserFontSet::UserFontCache::Shutdown();
if (mWordCacheExpirationTimer) {
mWordCacheExpirationTimer->Cancel();
mWordCacheExpirationTimer = nullptr;
}
// Expire everything that has a zero refcount, so we don't leak them.
AgeAllGenerations();
// All fonts should be gone.
NS_WARN_IF_FALSE(mFonts.Count() == 0,
"Fonts still alive while shutting down gfxFontCache");
// Note that we have to delete everything through the expiration
// tracker, since there might be fonts not in the hashtable but in
// the tracker.
}
bool
gfxFontCache::HashEntry::KeyEquals(const KeyTypePointer aKey) const
{
const gfxCharacterMap* fontUnicodeRangeMap = mFont->GetUnicodeRangeMap();
return aKey->mFontEntry == mFont->GetFontEntry() &&
aKey->mStyle->Equals(*mFont->GetStyle()) &&
((!aKey->mUnicodeRangeMap && !fontUnicodeRangeMap) ||
(aKey->mUnicodeRangeMap && fontUnicodeRangeMap &&
aKey->mUnicodeRangeMap->Equals(fontUnicodeRangeMap)));
}
already_AddRefed<gfxFont>
gfxFontCache::Lookup(const gfxFontEntry* aFontEntry,
const gfxFontStyle* aStyle,
const gfxCharacterMap* aUnicodeRangeMap)
{
Key key(aFontEntry, aStyle, aUnicodeRangeMap);
HashEntry *entry = mFonts.GetEntry(key);
Telemetry::Accumulate(Telemetry::FONT_CACHE_HIT, entry != nullptr);
if (!entry)
return nullptr;
RefPtr<gfxFont> font = entry->mFont;
return font.forget();
}
void
gfxFontCache::AddNew(gfxFont *aFont)
{
Key key(aFont->GetFontEntry(), aFont->GetStyle(),
aFont->GetUnicodeRangeMap());
HashEntry *entry = mFonts.PutEntry(key);
if (!entry)
return;
gfxFont *oldFont = entry->mFont;
entry->mFont = aFont;
// Assert that we can find the entry we just put in (this fails if the key
// has a NaN float value in it, e.g. 'sizeAdjust').
MOZ_ASSERT(entry == mFonts.GetEntry(key));
// If someone's asked us to replace an existing font entry, then that's a
// bit weird, but let it happen, and expire the old font if it's not used.
if (oldFont && oldFont->GetExpirationState()->IsTracked()) {
// if oldFont == aFont, recount should be > 0,
// so we shouldn't be here.
NS_ASSERTION(aFont != oldFont, "new font is tracked for expiry!");
NotifyExpired(oldFont);
}
}
void
gfxFontCache::NotifyReleased(gfxFont *aFont)
{
nsresult rv = AddObject(aFont);
if (NS_FAILED(rv)) {
// We couldn't track it for some reason. Kill it now.
DestroyFont(aFont);
}
// Note that we might have fonts that aren't in the hashtable, perhaps because
// of OOM adding to the hashtable or because someone did an AddNew where
// we already had a font. These fonts are added to the expiration tracker
// anyway, even though Lookup can't resurrect them. Eventually they will
// expire and be deleted.
}
void
gfxFontCache::NotifyExpired(gfxFont *aFont)
{
aFont->ClearCachedWords();
RemoveObject(aFont);
DestroyFont(aFont);
}
void
gfxFontCache::DestroyFont(gfxFont *aFont)
{
Key key(aFont->GetFontEntry(), aFont->GetStyle(),
aFont->GetUnicodeRangeMap());
HashEntry *entry = mFonts.GetEntry(key);
if (entry && entry->mFont == aFont) {
mFonts.RemoveEntry(entry);
}
NS_ASSERTION(aFont->GetRefCount() == 0,
"Destroying with non-zero ref count!");
delete aFont;
}
/*static*/
void
gfxFontCache::WordCacheExpirationTimerCallback(nsITimer* aTimer, void* aCache)
{
gfxFontCache* cache = static_cast<gfxFontCache*>(aCache);
for (auto it = cache->mFonts.Iter(); !it.Done(); it.Next()) {
it.Get()->mFont->AgeCachedWords();
}
}
void
gfxFontCache::FlushShapedWordCaches()
{
for (auto it = mFonts.Iter(); !it.Done(); it.Next()) {
it.Get()->mFont->ClearCachedWords();
}
}
void
gfxFontCache::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const
{
// TODO: add the overhead of the expiration tracker (generation arrays)
aSizes->mFontInstances += mFonts.ShallowSizeOfExcludingThis(aMallocSizeOf);
for (auto iter = mFonts.ConstIter(); !iter.Done(); iter.Next()) {
iter.Get()->mFont->AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
}
}
void
gfxFontCache::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const
{
aSizes->mFontInstances += aMallocSizeOf(this);
AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
}
#define MAX_SSXX_VALUE 99
#define MAX_CVXX_VALUE 99
static void
LookupAlternateValues(gfxFontFeatureValueSet *featureLookup,
const nsAString& aFamily,
const nsTArray<gfxAlternateValue>& altValue,
nsTArray<gfxFontFeature>& aFontFeatures)
{
uint32_t numAlternates = altValue.Length();
for (uint32_t i = 0; i < numAlternates; i++) {
const gfxAlternateValue& av = altValue.ElementAt(i);
nsAutoTArray<uint32_t,4> values;
// map <family, name, feature> ==> <values>
bool found =
featureLookup->GetFontFeatureValuesFor(aFamily, av.alternate,
av.value, values);
uint32_t numValues = values.Length();
// nothing defined, skip
if (!found || numValues == 0) {
continue;
}
gfxFontFeature feature;
if (av.alternate == NS_FONT_VARIANT_ALTERNATES_CHARACTER_VARIANT) {
NS_ASSERTION(numValues <= 2,
"too many values allowed for character-variant");
// character-variant(12 3) ==> 'cv12' = 3
uint32_t nn = values.ElementAt(0);
// ignore values greater than 99
if (nn == 0 || nn > MAX_CVXX_VALUE) {
continue;
}
feature.mValue = 1;
if (numValues > 1) {
feature.mValue = values.ElementAt(1);
}
feature.mTag = HB_TAG('c','v',('0' + nn / 10), ('0' + nn % 10));
aFontFeatures.AppendElement(feature);
} else if (av.alternate == NS_FONT_VARIANT_ALTERNATES_STYLESET) {
// styleset(1 2 7) ==> 'ss01' = 1, 'ss02' = 1, 'ss07' = 1
feature.mValue = 1;
for (uint32_t v = 0; v < numValues; v++) {
uint32_t nn = values.ElementAt(v);
if (nn == 0 || nn > MAX_SSXX_VALUE) {
continue;
}
feature.mTag = HB_TAG('s','s',('0' + nn / 10), ('0' + nn % 10));
aFontFeatures.AppendElement(feature);
}
} else {
NS_ASSERTION(numValues == 1,
"too many values for font-specific font-variant-alternates");
feature.mValue = values.ElementAt(0);
switch (av.alternate) {
case NS_FONT_VARIANT_ALTERNATES_STYLISTIC: // salt
feature.mTag = HB_TAG('s','a','l','t');
break;
case NS_FONT_VARIANT_ALTERNATES_SWASH: // swsh, cswh
feature.mTag = HB_TAG('s','w','s','h');
aFontFeatures.AppendElement(feature);
feature.mTag = HB_TAG('c','s','w','h');
break;
case NS_FONT_VARIANT_ALTERNATES_ORNAMENTS: // ornm
feature.mTag = HB_TAG('o','r','n','m');
break;
case NS_FONT_VARIANT_ALTERNATES_ANNOTATION: // nalt
feature.mTag = HB_TAG('n','a','l','t');
break;
default:
feature.mTag = 0;
break;
}
NS_ASSERTION(feature.mTag, "unsupported alternate type");
if (!feature.mTag) {
continue;
}
aFontFeatures.AppendElement(feature);
}
}
}
/* static */ void
gfxFontShaper::MergeFontFeatures(
const gfxFontStyle *aStyle,
const nsTArray<gfxFontFeature>& aFontFeatures,
bool aDisableLigatures,
const nsAString& aFamilyName,
bool aAddSmallCaps,
void (*aHandleFeature)(const uint32_t&, uint32_t&, void*),
void* aHandleFeatureData)
{
uint32_t numAlts = aStyle->alternateValues.Length();
const nsTArray<gfxFontFeature>& styleRuleFeatures =
aStyle->featureSettings;
// Bail immediately if nothing to do, which is the common case.
if (styleRuleFeatures.IsEmpty() &&
aFontFeatures.IsEmpty() &&
!aDisableLigatures &&
aStyle->variantCaps == NS_FONT_VARIANT_CAPS_NORMAL &&
aStyle->variantSubSuper == NS_FONT_VARIANT_POSITION_NORMAL &&
numAlts == 0) {
return;
}
nsDataHashtable<nsUint32HashKey,uint32_t> mergedFeatures;
// Ligature features are enabled by default in the generic shaper,
// so we explicitly turn them off if necessary (for letter-spacing)
if (aDisableLigatures) {
mergedFeatures.Put(HB_TAG('l','i','g','a'), 0);
mergedFeatures.Put(HB_TAG('c','l','i','g'), 0);
}
// add feature values from font
uint32_t i, count;
count = aFontFeatures.Length();
for (i = 0; i < count; i++) {
const gfxFontFeature& feature = aFontFeatures.ElementAt(i);
mergedFeatures.Put(feature.mTag, feature.mValue);
}
// font-variant-caps - handled here due to the need for fallback handling
// petite caps cases can fallback to appropriate smallcaps
uint32_t variantCaps = aStyle->variantCaps;
switch (variantCaps) {
case NS_FONT_VARIANT_CAPS_NORMAL:
break;
case NS_FONT_VARIANT_CAPS_ALLSMALL:
mergedFeatures.Put(HB_TAG('c','2','s','c'), 1);
// fall through to the small-caps case
MOZ_FALLTHROUGH;
case NS_FONT_VARIANT_CAPS_SMALLCAPS:
mergedFeatures.Put(HB_TAG('s','m','c','p'), 1);
break;
case NS_FONT_VARIANT_CAPS_ALLPETITE:
mergedFeatures.Put(aAddSmallCaps ? HB_TAG('c','2','s','c') :
HB_TAG('c','2','p','c'), 1);
// fall through to the petite-caps case
MOZ_FALLTHROUGH;
case NS_FONT_VARIANT_CAPS_PETITECAPS:
mergedFeatures.Put(aAddSmallCaps ? HB_TAG('s','m','c','p') :
HB_TAG('p','c','a','p'), 1);
break;
case NS_FONT_VARIANT_CAPS_TITLING:
mergedFeatures.Put(HB_TAG('t','i','t','l'), 1);
break;
case NS_FONT_VARIANT_CAPS_UNICASE:
mergedFeatures.Put(HB_TAG('u','n','i','c'), 1);
break;
default:
MOZ_ASSERT_UNREACHABLE("Unexpected variantCaps");
break;
}
// font-variant-position - handled here due to the need for fallback
switch (aStyle->variantSubSuper) {
case NS_FONT_VARIANT_POSITION_NORMAL:
break;
case NS_FONT_VARIANT_POSITION_SUPER:
mergedFeatures.Put(HB_TAG('s','u','p','s'), 1);
break;
case NS_FONT_VARIANT_POSITION_SUB:
mergedFeatures.Put(HB_TAG('s','u','b','s'), 1);
break;
default:
MOZ_ASSERT_UNREACHABLE("Unexpected variantSubSuper");
break;
}
// add font-specific feature values from style rules
if (aStyle->featureValueLookup && numAlts > 0) {
nsAutoTArray<gfxFontFeature,4> featureList;
// insert list of alternate feature settings
LookupAlternateValues(aStyle->featureValueLookup, aFamilyName,
aStyle->alternateValues, featureList);
count = featureList.Length();
for (i = 0; i < count; i++) {
const gfxFontFeature& feature = featureList.ElementAt(i);
mergedFeatures.Put(feature.mTag, feature.mValue);
}
}
// add feature values from style rules
count = styleRuleFeatures.Length();
for (i = 0; i < count; i++) {
const gfxFontFeature& feature = styleRuleFeatures.ElementAt(i);
mergedFeatures.Put(feature.mTag, feature.mValue);
}
if (mergedFeatures.Count() != 0) {
for (auto iter = mergedFeatures.Iter(); !iter.Done(); iter.Next()) {
aHandleFeature(iter.Key(), iter.Data(), aHandleFeatureData);
}
}
}
// Work out whether cairo will snap inter-glyph spacing to pixels.
//
// Layout does not align text to pixel boundaries, so, with font drawing
// backends that snap glyph positions to pixels, it is important that
// inter-glyph spacing within words is always an integer number of pixels.
// This ensures that the drawing backend snaps all of the word's glyphs in the
// same direction and so inter-glyph spacing remains the same.
//
/* static */ void
gfxFontShaper::GetRoundOffsetsToPixels(DrawTarget* aDrawTarget,
bool* aRoundX, bool* aRoundY)
{
*aRoundX = false;
// Could do something fancy here for ScaleFactors of
// AxisAlignedTransforms, but we leave things simple.
// Not much point rounding if a matrix will mess things up anyway.
// Also return false for non-cairo contexts.
if (aDrawTarget->GetTransform().HasNonTranslation()) {
*aRoundY = false;
return;
}
// All raster backends snap glyphs to pixels vertically.
// Print backends set CAIRO_HINT_METRICS_OFF.
*aRoundY = true;
cairo_t* cr = gfxFont::RefCairo(aDrawTarget);
cairo_scaled_font_t *scaled_font = cairo_get_scaled_font(cr);
// bug 1198921 - this sometimes fails under Windows for whatver reason
NS_ASSERTION(scaled_font, "null cairo scaled font should never be returned "
"by cairo_get_scaled_font");
if (!scaled_font) {
*aRoundX = true; // default to the same as the fallback path below
return;
}
// Sometimes hint metrics gets set for us, most notably for printing.
cairo_font_options_t *font_options = cairo_font_options_create();
cairo_scaled_font_get_font_options(scaled_font, font_options);
cairo_hint_metrics_t hint_metrics =
cairo_font_options_get_hint_metrics(font_options);
cairo_font_options_destroy(font_options);
switch (hint_metrics) {
case CAIRO_HINT_METRICS_OFF:
*aRoundY = false;
return;
case CAIRO_HINT_METRICS_DEFAULT:
// Here we mimic what cairo surface/font backends do. Printing
// surfaces have already been handled by hint_metrics. The
// fallback show_glyphs implementation composites pixel-aligned
// glyph surfaces, so we just pick surface/font combinations that
// override this.
switch (cairo_scaled_font_get_type(scaled_font)) {
#if CAIRO_HAS_DWRITE_FONT // dwrite backend is not in std cairo releases yet
case CAIRO_FONT_TYPE_DWRITE:
// show_glyphs is implemented on the font and so is used for
// all surface types; however, it may pixel-snap depending on
// the dwrite rendering mode
if (!cairo_dwrite_scaled_font_get_force_GDI_classic(scaled_font) &&
gfxWindowsPlatform::GetPlatform()->DWriteMeasuringMode() ==
DWRITE_MEASURING_MODE_NATURAL) {
return;
}
MOZ_FALLTHROUGH;
#endif
case CAIRO_FONT_TYPE_QUARTZ:
// Quartz surfaces implement show_glyphs for Quartz fonts
if (cairo_surface_get_type(cairo_get_target(cr)) ==
CAIRO_SURFACE_TYPE_QUARTZ) {
return;
}
break;
default:
break;
}
break;
case CAIRO_HINT_METRICS_ON:
break;
}
*aRoundX = true;
}
void
gfxShapedText::SetupClusterBoundaries(uint32_t aOffset,
const char16_t *aString,
uint32_t aLength)
{
CompressedGlyph *glyphs = GetCharacterGlyphs() + aOffset;
gfxTextRun::CompressedGlyph extendCluster;
extendCluster.SetComplex(false, true, 0);
ClusterIterator iter(aString, aLength);
// the ClusterIterator won't be able to tell us if the string
// _begins_ with a cluster-extender, so we handle that here
if (aLength) {
uint32_t ch = *aString;
if (aLength > 1 && NS_IS_HIGH_SURROGATE(ch) &&
NS_IS_LOW_SURROGATE(aString[1])) {
ch = SURROGATE_TO_UCS4(ch, aString[1]);
}
if (IsClusterExtender(ch)) {
*glyphs = extendCluster;
}
}
while (!iter.AtEnd()) {
if (*iter == char16_t(' ')) {
glyphs->SetIsSpace();
}
// advance iter to the next cluster-start (or end of text)
iter.Next();
// step past the first char of the cluster
aString++;
glyphs++;
// mark all the rest as cluster-continuations
while (aString < iter) {
*glyphs = extendCluster;
glyphs++;
aString++;
}
}
}
void
gfxShapedText::SetupClusterBoundaries(uint32_t aOffset,
const uint8_t *aString,
uint32_t aLength)
{
CompressedGlyph *glyphs = GetCharacterGlyphs() + aOffset;
const uint8_t *limit = aString + aLength;
while (aString < limit) {
if (*aString == uint8_t(' ')) {
glyphs->SetIsSpace();
}
aString++;
glyphs++;
}
}
gfxShapedText::DetailedGlyph *
gfxShapedText::AllocateDetailedGlyphs(uint32_t aIndex, uint32_t aCount)
{
NS_ASSERTION(aIndex < GetLength(), "Index out of range");
if (!mDetailedGlyphs) {
mDetailedGlyphs = new DetailedGlyphStore();
}
return mDetailedGlyphs->Allocate(aIndex, aCount);
}
void
gfxShapedText::SetGlyphs(uint32_t aIndex, CompressedGlyph aGlyph,
const DetailedGlyph *aGlyphs)
{
NS_ASSERTION(!aGlyph.IsSimpleGlyph(), "Simple glyphs not handled here");
NS_ASSERTION(aIndex > 0 || aGlyph.IsLigatureGroupStart(),
"First character can't be a ligature continuation!");
uint32_t glyphCount = aGlyph.GetGlyphCount();
if (glyphCount > 0) {
DetailedGlyph *details = AllocateDetailedGlyphs(aIndex, glyphCount);
memcpy(details, aGlyphs, sizeof(DetailedGlyph)*glyphCount);
}
GetCharacterGlyphs()[aIndex] = aGlyph;
}
#define ZWNJ 0x200C
#define ZWJ 0x200D
static inline bool
IsDefaultIgnorable(uint32_t aChar)
{
return GetIdentifierModification(aChar) == XIDMOD_DEFAULT_IGNORABLE ||
aChar == ZWNJ || aChar == ZWJ;
}
void
gfxShapedText::SetMissingGlyph(uint32_t aIndex, uint32_t aChar, gfxFont *aFont)
{
uint8_t category = GetGeneralCategory(aChar);
if (category >= HB_UNICODE_GENERAL_CATEGORY_SPACING_MARK &&
category <= HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)
{
GetCharacterGlyphs()[aIndex].SetComplex(false, true, 0);
}
DetailedGlyph *details = AllocateDetailedGlyphs(aIndex, 1);
details->mGlyphID = aChar;
if (IsDefaultIgnorable(aChar)) {
// Setting advance width to zero will prevent drawing the hexbox
details->mAdvance = 0;
} else {
gfxFloat width =
std::max(aFont->GetMetrics(gfxFont::eHorizontal).aveCharWidth,
gfxFloat(gfxFontMissingGlyphs::GetDesiredMinWidth(aChar,
mAppUnitsPerDevUnit)));
details->mAdvance = uint32_t(width * mAppUnitsPerDevUnit);
}
details->mXOffset = 0;
details->mYOffset = 0;
GetCharacterGlyphs()[aIndex].SetMissing(1);
}
bool
gfxShapedText::FilterIfIgnorable(uint32_t aIndex, uint32_t aCh)
{
if (IsDefaultIgnorable(aCh)) {
DetailedGlyph *details = AllocateDetailedGlyphs(aIndex, 1);
details->mGlyphID = aCh;
details->mAdvance = 0;
details->mXOffset = 0;
details->mYOffset = 0;
GetCharacterGlyphs()[aIndex].SetMissing(1);
return true;
}
return false;
}
void
gfxShapedText::AdjustAdvancesForSyntheticBold(float aSynBoldOffset,
uint32_t aOffset,
uint32_t aLength)
{
uint32_t synAppUnitOffset = aSynBoldOffset * mAppUnitsPerDevUnit;
CompressedGlyph *charGlyphs = GetCharacterGlyphs();
for (uint32_t i = aOffset; i < aOffset + aLength; ++i) {
CompressedGlyph *glyphData = charGlyphs + i;
if (glyphData->IsSimpleGlyph()) {
// simple glyphs ==> just add the advance
int32_t advance = glyphData->GetSimpleAdvance() + synAppUnitOffset;
if (CompressedGlyph::IsSimpleAdvance(advance)) {
glyphData->SetSimpleGlyph(advance, glyphData->GetSimpleGlyph());
} else {
// rare case, tested by making this the default
uint32_t glyphIndex = glyphData->GetSimpleGlyph();
glyphData->SetComplex(true, true, 1);
DetailedGlyph detail = {glyphIndex, advance, 0, 0};
SetGlyphs(i, *glyphData, &detail);
}
} else {
// complex glyphs ==> add offset at cluster/ligature boundaries
uint32_t detailedLength = glyphData->GetGlyphCount();
if (detailedLength) {
DetailedGlyph *details = GetDetailedGlyphs(i);
if (!details) {
continue;
}
if (IsRightToLeft()) {
details[0].mAdvance += synAppUnitOffset;
} else {
details[detailedLength - 1].mAdvance += synAppUnitOffset;
}
}
}
}
}
void
gfxFont::RunMetrics::CombineWith(const RunMetrics& aOther, bool aOtherIsOnLeft)
{
mAscent = std::max(mAscent, aOther.mAscent);
mDescent = std::max(mDescent, aOther.mDescent);
if (aOtherIsOnLeft) {
mBoundingBox =
(mBoundingBox + gfxPoint(aOther.mAdvanceWidth, 0)).Union(aOther.mBoundingBox);
} else {
mBoundingBox =
mBoundingBox.Union(aOther.mBoundingBox + gfxPoint(mAdvanceWidth, 0));
}
mAdvanceWidth += aOther.mAdvanceWidth;
}
gfxFont::gfxFont(gfxFontEntry *aFontEntry, const gfxFontStyle *aFontStyle,
AntialiasOption anAAOption, cairo_scaled_font_t *aScaledFont) :
mScaledFont(aScaledFont),
mFontEntry(aFontEntry), mIsValid(true),
mApplySyntheticBold(false),
mStyle(*aFontStyle),
mAdjustedSize(0.0),
mFUnitsConvFactor(-1.0f), // negative to indicate "not yet initialized"
mAntialiasOption(anAAOption)
{
#ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
++gFontCount;
#endif
mKerningSet = HasFeatureSet(HB_TAG('k','e','r','n'), mKerningEnabled);
}
gfxFont::~gfxFont()
{
uint32_t i, count = mGlyphExtentsArray.Length();
// We destroy the contents of mGlyphExtentsArray explicitly instead of
// using nsAutoPtr because VC++ can't deal with nsTArrays of nsAutoPtrs
// of classes that lack a proper copy constructor
for (i = 0; i < count; ++i) {
delete mGlyphExtentsArray[i];
}
mFontEntry->NotifyFontDestroyed(this);
if (mGlyphChangeObservers) {
for (auto it = mGlyphChangeObservers->Iter(); !it.Done(); it.Next()) {
it.Get()->GetKey()->ForgetFont();
}
}
}
gfxFloat
gfxFont::GetGlyphHAdvance(gfxContext *aCtx, uint16_t aGID)
{
if (!SetupCairoFont(aCtx->GetDrawTarget())) {
return 0;
}
if (ProvidesGlyphWidths()) {
return GetGlyphWidth(*aCtx->GetDrawTarget(), aGID) / 65536.0;
}
if (mFUnitsConvFactor < 0.0f) {
GetMetrics(eHorizontal);
}
NS_ASSERTION(mFUnitsConvFactor >= 0.0f,
"missing font unit conversion factor");
if (!mHarfBuzzShaper) {
mHarfBuzzShaper = new gfxHarfBuzzShaper(this);
}
gfxHarfBuzzShaper* shaper =
static_cast<gfxHarfBuzzShaper*>(mHarfBuzzShaper.get());
if (!shaper->Initialize()) {
return 0;
}
return shaper->GetGlyphHAdvance(aGID) / 65536.0;
}
static void
CollectLookupsByFeature(hb_face_t *aFace, hb_tag_t aTableTag,
uint32_t aFeatureIndex, hb_set_t *aLookups)
{
uint32_t lookups[32];
uint32_t i, len, offset;
offset = 0;
do {
len = ArrayLength(lookups);
hb_ot_layout_feature_get_lookups(aFace, aTableTag, aFeatureIndex,
offset, &len, lookups);
for (i = 0; i < len; i++) {
hb_set_add(aLookups, lookups[i]);
}
offset += len;
} while (len == ArrayLength(lookups));
}
static void
CollectLookupsByLanguage(hb_face_t *aFace, hb_tag_t aTableTag,
const nsTHashtable<nsUint32HashKey>&
aSpecificFeatures,
hb_set_t *aOtherLookups,
hb_set_t *aSpecificFeatureLookups,
uint32_t aScriptIndex, uint32_t aLangIndex)
{
uint32_t reqFeatureIndex;
if (hb_ot_layout_language_get_required_feature_index(aFace, aTableTag,
aScriptIndex,
aLangIndex,
&reqFeatureIndex)) {
CollectLookupsByFeature(aFace, aTableTag, reqFeatureIndex,
aOtherLookups);
}
uint32_t featureIndexes[32];
uint32_t i, len, offset;
offset = 0;
do {
len = ArrayLength(featureIndexes);
hb_ot_layout_language_get_feature_indexes(aFace, aTableTag,
aScriptIndex, aLangIndex,
offset, &len, featureIndexes);
for (i = 0; i < len; i++) {
uint32_t featureIndex = featureIndexes[i];
// get the feature tag
hb_tag_t featureTag;
uint32_t tagLen = 1;
hb_ot_layout_language_get_feature_tags(aFace, aTableTag,
aScriptIndex, aLangIndex,
offset + i, &tagLen,
&featureTag);
// collect lookups
hb_set_t *lookups = aSpecificFeatures.GetEntry(featureTag) ?
aSpecificFeatureLookups : aOtherLookups;
CollectLookupsByFeature(aFace, aTableTag, featureIndex, lookups);
}
offset += len;
} while (len == ArrayLength(featureIndexes));
}
static bool
HasLookupRuleWithGlyphByScript(hb_face_t *aFace, hb_tag_t aTableTag,
hb_tag_t aScriptTag, uint32_t aScriptIndex,
uint16_t aGlyph,
const nsTHashtable<nsUint32HashKey>&
aDefaultFeatures,
bool& aHasDefaultFeatureWithGlyph)
{
uint32_t numLangs, lang;
hb_set_t *defaultFeatureLookups = hb_set_create();
hb_set_t *nonDefaultFeatureLookups = hb_set_create();
// default lang
CollectLookupsByLanguage(aFace, aTableTag, aDefaultFeatures,
nonDefaultFeatureLookups, defaultFeatureLookups,
aScriptIndex,
HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX);
// iterate over langs
numLangs = hb_ot_layout_script_get_language_tags(aFace, aTableTag,
aScriptIndex, 0,
nullptr, nullptr);
for (lang = 0; lang < numLangs; lang++) {
CollectLookupsByLanguage(aFace, aTableTag, aDefaultFeatures,
nonDefaultFeatureLookups,
defaultFeatureLookups,
aScriptIndex, lang);
}
// look for the glyph among default feature lookups
aHasDefaultFeatureWithGlyph = false;
hb_set_t *glyphs = hb_set_create();
hb_codepoint_t index = -1;
while (hb_set_next(defaultFeatureLookups, &index)) {
hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
glyphs, glyphs, glyphs,
nullptr);
if (hb_set_has(glyphs, aGlyph)) {
aHasDefaultFeatureWithGlyph = true;
break;
}
}
// look for the glyph among non-default feature lookups
// if no default feature lookups contained spaces
bool hasNonDefaultFeatureWithGlyph = false;
if (!aHasDefaultFeatureWithGlyph) {
hb_set_clear(glyphs);
index = -1;
while (hb_set_next(nonDefaultFeatureLookups, &index)) {
hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
glyphs, glyphs, glyphs,
nullptr);
if (hb_set_has(glyphs, aGlyph)) {
hasNonDefaultFeatureWithGlyph = true;
break;
}
}
}
hb_set_destroy(glyphs);
hb_set_destroy(defaultFeatureLookups);
hb_set_destroy(nonDefaultFeatureLookups);
return aHasDefaultFeatureWithGlyph || hasNonDefaultFeatureWithGlyph;
}
static void
HasLookupRuleWithGlyph(hb_face_t *aFace, hb_tag_t aTableTag, bool& aHasGlyph,
hb_tag_t aSpecificFeature, bool& aHasGlyphSpecific,
uint16_t aGlyph)
{
// iterate over the scripts in the font
uint32_t numScripts, numLangs, script, lang;
hb_set_t *otherLookups = hb_set_create();
hb_set_t *specificFeatureLookups = hb_set_create();
nsTHashtable<nsUint32HashKey> specificFeature;
specificFeature.PutEntry(aSpecificFeature);
numScripts = hb_ot_layout_table_get_script_tags(aFace, aTableTag, 0,
nullptr, nullptr);
for (script = 0; script < numScripts; script++) {
// default lang
CollectLookupsByLanguage(aFace, aTableTag, specificFeature,
otherLookups, specificFeatureLookups,
script, HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX);
// iterate over langs
numLangs = hb_ot_layout_script_get_language_tags(aFace, HB_OT_TAG_GPOS,
script, 0,
nullptr, nullptr);
for (lang = 0; lang < numLangs; lang++) {
CollectLookupsByLanguage(aFace, aTableTag, specificFeature,
otherLookups, specificFeatureLookups,
script, lang);
}
}
// look for the glyph among non-specific feature lookups
hb_set_t *glyphs = hb_set_create();
hb_codepoint_t index = -1;
while (hb_set_next(otherLookups, &index)) {
hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
glyphs, glyphs, glyphs,
nullptr);
if (hb_set_has(glyphs, aGlyph)) {
aHasGlyph = true;
break;
}
}
// look for the glyph among specific feature lookups
hb_set_clear(glyphs);
index = -1;
while (hb_set_next(specificFeatureLookups, &index)) {
hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
glyphs, glyphs, glyphs,
nullptr);
if (hb_set_has(glyphs, aGlyph)) {
aHasGlyphSpecific = true;
break;
}
}
hb_set_destroy(glyphs);
hb_set_destroy(specificFeatureLookups);
hb_set_destroy(otherLookups);
}
nsDataHashtable<nsUint32HashKey, int32_t> *gfxFont::sScriptTagToCode = nullptr;
nsTHashtable<nsUint32HashKey> *gfxFont::sDefaultFeatures = nullptr;
static inline bool
HasSubstitution(uint32_t *aBitVector, uint32_t aBit) {
return (aBitVector[aBit >> 5] & (1 << (aBit & 0x1f))) != 0;
}
// union of all default substitution features across scripts
static const hb_tag_t defaultFeatures[] = {
HB_TAG('a','b','v','f'),
HB_TAG('a','b','v','s'),
HB_TAG('a','k','h','n'),
HB_TAG('b','l','w','f'),
HB_TAG('b','l','w','s'),
HB_TAG('c','a','l','t'),
HB_TAG('c','c','m','p'),
HB_TAG('c','f','a','r'),
HB_TAG('c','j','c','t'),
HB_TAG('c','l','i','g'),
HB_TAG('f','i','n','2'),
HB_TAG('f','i','n','3'),
HB_TAG('f','i','n','a'),
HB_TAG('h','a','l','f'),
HB_TAG('h','a','l','n'),
HB_TAG('i','n','i','t'),
HB_TAG('i','s','o','l'),
HB_TAG('l','i','g','a'),
HB_TAG('l','j','m','o'),
HB_TAG('l','o','c','l'),
HB_TAG('l','t','r','a'),
HB_TAG('l','t','r','m'),
HB_TAG('m','e','d','2'),
HB_TAG('m','e','d','i'),
HB_TAG('m','s','e','t'),
HB_TAG('n','u','k','t'),
HB_TAG('p','r','e','f'),
HB_TAG('p','r','e','s'),
HB_TAG('p','s','t','f'),
HB_TAG('p','s','t','s'),
HB_TAG('r','c','l','t'),
HB_TAG('r','l','i','g'),
HB_TAG('r','k','r','f'),
HB_TAG('r','p','h','f'),
HB_TAG('r','t','l','a'),
HB_TAG('r','t','l','m'),
HB_TAG('t','j','m','o'),
HB_TAG('v','a','t','u'),
HB_TAG('v','e','r','t'),
HB_TAG('v','j','m','o')
};
void
gfxFont::CheckForFeaturesInvolvingSpace()
{
mFontEntry->mHasSpaceFeaturesInitialized = true;
bool log = LOG_FONTINIT_ENABLED();
TimeStamp start;
if (MOZ_UNLIKELY(log)) {
start = TimeStamp::Now();
}
bool result = false;
uint32_t spaceGlyph = GetSpaceGlyph();
if (!spaceGlyph) {
return;
}
hb_face_t *face = GetFontEntry()->GetHBFace();
// GSUB lookups - examine per script
if (hb_ot_layout_has_substitution(face)) {
// set up the script ==> code hashtable if needed
if (!sScriptTagToCode) {
sScriptTagToCode =
new nsDataHashtable<nsUint32HashKey,
int32_t>(MOZ_NUM_SCRIPT_CODES);
sScriptTagToCode->Put(HB_TAG('D','F','L','T'), MOZ_SCRIPT_COMMON);
for (int32_t s = MOZ_SCRIPT_ARABIC; s < MOZ_NUM_SCRIPT_CODES; s++) {
hb_script_t scriptTag = hb_script_t(GetScriptTagForCode(s));
hb_tag_t s1, s2;
hb_ot_tags_from_script(scriptTag, &s1, &s2);
sScriptTagToCode->Put(s1, s);
if (s2 != HB_OT_TAG_DEFAULT_SCRIPT) {
sScriptTagToCode->Put(s2, s);
}
}
uint32_t numDefaultFeatures = ArrayLength(defaultFeatures);
sDefaultFeatures =
new nsTHashtable<nsUint32HashKey>(numDefaultFeatures);
for (uint32_t i = 0; i < numDefaultFeatures; i++) {
sDefaultFeatures->PutEntry(defaultFeatures[i]);
}
}
// iterate over the scripts in the font
hb_tag_t scriptTags[8];
uint32_t len, offset = 0;
do {
len = ArrayLength(scriptTags);
hb_ot_layout_table_get_script_tags(face, HB_OT_TAG_GSUB, offset,
&len, scriptTags);
for (uint32_t i = 0; i < len; i++) {
bool isDefaultFeature = false;
int32_t s;
if (!HasLookupRuleWithGlyphByScript(face, HB_OT_TAG_GSUB,
scriptTags[i], offset + i,
spaceGlyph,
*sDefaultFeatures,
isDefaultFeature) ||
!sScriptTagToCode->Get(scriptTags[i], &s))
{
continue;
}
result = true;
uint32_t index = s >> 5;
uint32_t bit = s & 0x1f;
if (isDefaultFeature) {
mFontEntry->mDefaultSubSpaceFeatures[index] |= (1 << bit);
} else {
mFontEntry->mNonDefaultSubSpaceFeatures[index] |= (1 << bit);
}
}
offset += len;
} while (len == ArrayLength(scriptTags));
}
// spaces in default features of default script?
// ==> can't use word cache, skip GPOS analysis
bool canUseWordCache = true;
if (HasSubstitution(mFontEntry->mDefaultSubSpaceFeatures,
MOZ_SCRIPT_COMMON)) {
canUseWordCache = false;
}
// GPOS lookups - distinguish kerning from non-kerning features
mFontEntry->mHasSpaceFeaturesKerning = false;
mFontEntry->mHasSpaceFeaturesNonKerning = false;
if (canUseWordCache && hb_ot_layout_has_positioning(face)) {
bool hasKerning = false, hasNonKerning = false;
HasLookupRuleWithGlyph(face, HB_OT_TAG_GPOS, hasNonKerning,
HB_TAG('k','e','r','n'), hasKerning, spaceGlyph);
if (hasKerning || hasNonKerning) {
result = true;
}
mFontEntry->mHasSpaceFeaturesKerning = hasKerning;
mFontEntry->mHasSpaceFeaturesNonKerning = hasNonKerning;
}
hb_face_destroy(face);
mFontEntry->mHasSpaceFeatures = result;
if (MOZ_UNLIKELY(log)) {
TimeDuration elapsed = TimeStamp::Now() - start;
LOG_FONTINIT((
"(fontinit-spacelookups) font: %s - "
"subst default: %8.8x %8.8x %8.8x %8.8x "
"subst non-default: %8.8x %8.8x %8.8x %8.8x "
"kerning: %s non-kerning: %s time: %6.3f\n",
NS_ConvertUTF16toUTF8(mFontEntry->Name()).get(),
mFontEntry->mDefaultSubSpaceFeatures[3],
mFontEntry->mDefaultSubSpaceFeatures[2],
mFontEntry->mDefaultSubSpaceFeatures[1],
mFontEntry->mDefaultSubSpaceFeatures[0],
mFontEntry->mNonDefaultSubSpaceFeatures[3],
mFontEntry->mNonDefaultSubSpaceFeatures[2],
mFontEntry->mNonDefaultSubSpaceFeatures[1],
mFontEntry->mNonDefaultSubSpaceFeatures[0],
(mFontEntry->mHasSpaceFeaturesKerning ? "true" : "false"),
(mFontEntry->mHasSpaceFeaturesNonKerning ? "true" : "false"),
elapsed.ToMilliseconds()
));
}
}
bool
gfxFont::HasSubstitutionRulesWithSpaceLookups(int32_t aRunScript)
{
NS_ASSERTION(GetFontEntry()->mHasSpaceFeaturesInitialized,
"need to initialize space lookup flags");
NS_ASSERTION(aRunScript < MOZ_NUM_SCRIPT_CODES, "weird script code");
if (aRunScript == MOZ_SCRIPT_INVALID ||
aRunScript >= MOZ_NUM_SCRIPT_CODES) {
return false;
}
// default features have space lookups ==> true
if (HasSubstitution(mFontEntry->mDefaultSubSpaceFeatures,
MOZ_SCRIPT_COMMON) ||
HasSubstitution(mFontEntry->mDefaultSubSpaceFeatures,
aRunScript))
{
return true;
}
// non-default features have space lookups and some type of
// font feature, in font or style is specified ==> true
if ((HasSubstitution(mFontEntry->mNonDefaultSubSpaceFeatures,
MOZ_SCRIPT_COMMON) ||
HasSubstitution(mFontEntry->mNonDefaultSubSpaceFeatures,
aRunScript)) &&
(!mStyle.featureSettings.IsEmpty() ||
!mFontEntry->mFeatureSettings.IsEmpty()))
{
return true;
}
return false;
}
bool
gfxFont::SpaceMayParticipateInShaping(int32_t aRunScript)
{
// avoid checking fonts known not to include default space-dependent features
if (MOZ_UNLIKELY(mFontEntry->mSkipDefaultFeatureSpaceCheck)) {
if (!mKerningSet && mStyle.featureSettings.IsEmpty() &&
mFontEntry->mFeatureSettings.IsEmpty()) {
return false;
}
}
if (FontCanSupportGraphite()) {
if (gfxPlatform::GetPlatform()->UseGraphiteShaping()) {
return mFontEntry->HasGraphiteSpaceContextuals();
}
}
// We record the presence of space-dependent features in the font entry
// so that subsequent instantiations for the same font face won't
// require us to re-check the tables; however, the actual check is done
// by gfxFont because not all font entry subclasses know how to create
// a harfbuzz face for introspection.
if (!mFontEntry->mHasSpaceFeaturesInitialized) {
CheckForFeaturesInvolvingSpace();
}
if (!mFontEntry->mHasSpaceFeatures) {
return false;
}
// if font has substitution rules or non-kerning positioning rules
// that involve spaces, bypass
if (HasSubstitutionRulesWithSpaceLookups(aRunScript) ||
mFontEntry->mHasSpaceFeaturesNonKerning) {
return true;
}
// if kerning explicitly enabled/disabled via font-feature-settings or
// font-kerning and kerning rules use spaces, only bypass when enabled
if (mKerningSet && mFontEntry->mHasSpaceFeaturesKerning) {
return mKerningEnabled;
}
return false;
}
bool
gfxFont::SupportsFeature(int32_t aScript, uint32_t aFeatureTag)
{
if (mGraphiteShaper && gfxPlatform::GetPlatform()->UseGraphiteShaping()) {
return GetFontEntry()->SupportsGraphiteFeature(aFeatureTag);
}
return GetFontEntry()->SupportsOpenTypeFeature(aScript, aFeatureTag);
}
bool
gfxFont::SupportsVariantCaps(int32_t aScript,
uint32_t aVariantCaps,
bool& aFallbackToSmallCaps,
bool& aSyntheticLowerToSmallCaps,
bool& aSyntheticUpperToSmallCaps)
{
bool ok = true; // cases without fallback are fine
aFallbackToSmallCaps = false;
aSyntheticLowerToSmallCaps = false;
aSyntheticUpperToSmallCaps = false;
switch (aVariantCaps) {
case NS_FONT_VARIANT_CAPS_SMALLCAPS:
ok = SupportsFeature(aScript, HB_TAG('s','m','c','p'));
if (!ok) {
aSyntheticLowerToSmallCaps = true;
}
break;
case NS_FONT_VARIANT_CAPS_ALLSMALL:
ok = SupportsFeature(aScript, HB_TAG('s','m','c','p')) &&
SupportsFeature(aScript, HB_TAG('c','2','s','c'));
if (!ok) {
aSyntheticLowerToSmallCaps = true;
aSyntheticUpperToSmallCaps = true;
}
break;
case NS_FONT_VARIANT_CAPS_PETITECAPS:
ok = SupportsFeature(aScript, HB_TAG('p','c','a','p'));
if (!ok) {
ok = SupportsFeature(aScript, HB_TAG('s','m','c','p'));
aFallbackToSmallCaps = ok;
}
if (!ok) {
aSyntheticLowerToSmallCaps = true;
}
break;
case NS_FONT_VARIANT_CAPS_ALLPETITE:
ok = SupportsFeature(aScript, HB_TAG('p','c','a','p')) &&
SupportsFeature(aScript, HB_TAG('c','2','p','c'));
if (!ok) {
ok = SupportsFeature(aScript, HB_TAG('s','m','c','p')) &&
SupportsFeature(aScript, HB_TAG('c','2','s','c'));
aFallbackToSmallCaps = ok;
}
if (!ok) {
aSyntheticLowerToSmallCaps = true;
aSyntheticUpperToSmallCaps = true;
}
break;
default:
break;
}
NS_ASSERTION(!(ok && (aSyntheticLowerToSmallCaps ||
aSyntheticUpperToSmallCaps)),
"shouldn't use synthetic features if we found real ones");
NS_ASSERTION(!(!ok && aFallbackToSmallCaps),
"if we found a usable fallback, that counts as ok");
return ok;
}
bool
gfxFont::SupportsSubSuperscript(uint32_t aSubSuperscript,
const uint8_t *aString,
uint32_t aLength, int32_t aRunScript)
{
NS_ConvertASCIItoUTF16 unicodeString(reinterpret_cast<const char*>(aString),
aLength);
return SupportsSubSuperscript(aSubSuperscript, unicodeString.get(),
aLength, aRunScript);
}
bool
gfxFont::SupportsSubSuperscript(uint32_t aSubSuperscript,
const char16_t *aString,
uint32_t aLength, int32_t aRunScript)
{
NS_ASSERTION(aSubSuperscript == NS_FONT_VARIANT_POSITION_SUPER ||
aSubSuperscript == NS_FONT_VARIANT_POSITION_SUB,
"unknown value of font-variant-position");
uint32_t feature = aSubSuperscript == NS_FONT_VARIANT_POSITION_SUPER ?
HB_TAG('s','u','p','s') : HB_TAG('s','u','b','s');
if (!SupportsFeature(aRunScript, feature)) {
return false;
}
// xxx - for graphite, don't really know how to sniff lookups so bail
if (mGraphiteShaper && gfxPlatform::GetPlatform()->UseGraphiteShaping()) {
return true;
}
if (!mHarfBuzzShaper) {
mHarfBuzzShaper = new gfxHarfBuzzShaper(this);
}
gfxHarfBuzzShaper* shaper =
static_cast<gfxHarfBuzzShaper*>(mHarfBuzzShaper.get());
if (!shaper->Initialize()) {
return false;
}
// get the hbset containing input glyphs for the feature
const hb_set_t *inputGlyphs = mFontEntry->InputsForOpenTypeFeature(aRunScript, feature);
// create an hbset containing default glyphs for the script run
hb_set_t *defaultGlyphsInRun = hb_set_create();
// for each character, get the glyph id
for (uint32_t i = 0; i < aLength; i++) {
uint32_t ch = aString[i];
if ((i + 1 < aLength) && NS_IS_HIGH_SURROGATE(ch) &&
NS_IS_LOW_SURROGATE(aString[i + 1])) {
i++;
ch = SURROGATE_TO_UCS4(ch, aString[i]);
}
if (ch == 0xa0) {
ch = ' ';
}
hb_codepoint_t gid = shaper->GetGlyph(ch, 0);
hb_set_add(defaultGlyphsInRun, gid);
}
// intersect with input glyphs, if size is not the same ==> fallback
uint32_t origSize = hb_set_get_population(defaultGlyphsInRun);
hb_set_intersect(defaultGlyphsInRun, inputGlyphs);
uint32_t intersectionSize = hb_set_get_population(defaultGlyphsInRun);
hb_set_destroy(defaultGlyphsInRun);
return origSize == intersectionSize;
}
bool
gfxFont::HasFeatureSet(uint32_t aFeature, bool& aFeatureOn)
{
aFeatureOn = false;
if (mStyle.featureSettings.IsEmpty() &&
GetFontEntry()->mFeatureSettings.IsEmpty()) {
return false;
}
// add feature values from font
bool featureSet = false;
uint32_t i, count;
nsTArray<gfxFontFeature>& fontFeatures = GetFontEntry()->mFeatureSettings;
count = fontFeatures.Length();
for (i = 0; i < count; i++) {
const gfxFontFeature& feature = fontFeatures.ElementAt(i);
if (feature.mTag == aFeature) {
featureSet = true;
aFeatureOn = (feature.mValue != 0);
}
}
// add feature values from style rules
nsTArray<gfxFontFeature>& styleFeatures = mStyle.featureSettings;
count = styleFeatures.Length();
for (i = 0; i < count; i++) {
const gfxFontFeature& feature = styleFeatures.ElementAt(i);
if (feature.mTag == aFeature) {
featureSet = true;
aFeatureOn = (feature.mValue != 0);
}
}
return featureSet;
}
/**
* A helper function in case we need to do any rounding or other
* processing here.
*/
#define ToDeviceUnits(aAppUnits, aDevUnitsPerAppUnit) \
(double(aAppUnits)*double(aDevUnitsPerAppUnit))
static AntialiasMode Get2DAAMode(gfxFont::AntialiasOption aAAOption) {
switch (aAAOption) {
case gfxFont::kAntialiasSubpixel:
return AntialiasMode::SUBPIXEL;
case gfxFont::kAntialiasGrayscale:
return AntialiasMode::GRAY;
case gfxFont::kAntialiasNone:
return AntialiasMode::NONE;
default:
return AntialiasMode::DEFAULT;
}
}
class GlyphBufferAzure
{
public:
GlyphBufferAzure(const TextRunDrawParams& aRunParams,
const FontDrawParams& aFontParams)
: mRunParams(aRunParams)
, mFontParams(aFontParams)
, mNumGlyphs(0)
{
}
~GlyphBufferAzure()
{
Flush(true); // flush any remaining buffered glyphs
}
void OutputGlyph(uint32_t aGlyphID, const gfxPoint& aPt)
{
Glyph *glyph = AppendGlyph();
glyph->mIndex = aGlyphID;
glyph->mPosition.x = aPt.x;
glyph->mPosition.y = aPt.y;
glyph->mPosition = mFontParams.matInv * glyph->mPosition;
Flush(false); // this will flush only if the buffer is full
}
const TextRunDrawParams& mRunParams;
const FontDrawParams& mFontParams;
private:
#define GLYPH_BUFFER_SIZE (2048/sizeof(Glyph))
Glyph *AppendGlyph()
{
return &mGlyphBuffer[mNumGlyphs++];
}
// Render the buffered glyphs to the draw target and clear the buffer.
// This actually flushes the glyphs only if the buffer is full, or if the
// aFinish parameter is true; otherwise it simply returns.
void Flush(bool aFinish)
{
// Ensure there's enough room for a glyph to be added to the buffer
if ((!aFinish && mNumGlyphs < GLYPH_BUFFER_SIZE) || !mNumGlyphs) {
return;
}
if (mRunParams.isRTL) {
Glyph *begin = &mGlyphBuffer[0];
Glyph *end = &mGlyphBuffer[mNumGlyphs];
std::reverse(begin, end);
}
gfx::GlyphBuffer buf;
buf.mGlyphs = mGlyphBuffer;
buf.mNumGlyphs = mNumGlyphs;
gfxContext::AzureState state = mRunParams.context->CurrentState();
if ((int(mRunParams.drawMode) &
(int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) ==
(int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) {
FlushStroke(buf, state);
}
if (int(mRunParams.drawMode) & int(DrawMode::GLYPH_FILL)) {
if (state.pattern || mFontParams.contextPaint) {
Pattern *pat;
RefPtr<gfxPattern> fillPattern;
if (!mFontParams.contextPaint ||
!(fillPattern = mFontParams.contextPaint->GetFillPattern(
mRunParams.context->GetDrawTarget(),
mRunParams.context->CurrentMatrix()))) {
if (state.pattern) {
pat = state.pattern->GetPattern(mRunParams.dt,
state.patternTransformChanged ?
&state.patternTransform : nullptr);
} else {
pat = nullptr;
}
} else {
pat = fillPattern->GetPattern(mRunParams.dt);
}
if (pat) {
Matrix saved;
Matrix *mat = nullptr;
if (mFontParams.passedInvMatrix) {
// The brush matrix needs to be multiplied with the
// inverted matrix as well, to move the brush into the
// space of the glyphs.
// This relies on the returned Pattern not to be reused
// by others, but regenerated on GetPattern calls. This
// is true!
if (pat->GetType() == PatternType::LINEAR_GRADIENT) {
mat = &static_cast<LinearGradientPattern*>(pat)->mMatrix;
} else if (pat->GetType() == PatternType::RADIAL_GRADIENT) {
mat = &static_cast<RadialGradientPattern*>(pat)->mMatrix;
} else if (pat->GetType() == PatternType::SURFACE) {
mat = &static_cast<SurfacePattern*>(pat)->mMatrix;
}
if (mat) {
saved = *mat;
*mat = (*mat) * (*mFontParams.passedInvMatrix);
}
}
mRunParams.dt->FillGlyphs(mFontParams.scaledFont, buf,
*pat, mFontParams.drawOptions,
mFontParams.renderingOptions);
if (mat) {
*mat = saved;
}
}
} else if (state.sourceSurface) {
mRunParams.dt->FillGlyphs(mFontParams.scaledFont, buf,
SurfacePattern(state.sourceSurface,
ExtendMode::CLAMP,
state.surfTransform),
mFontParams.drawOptions,
mFontParams.renderingOptions);
} else {
mRunParams.dt->FillGlyphs(mFontParams.scaledFont, buf,
ColorPattern(state.color),
mFontParams.drawOptions,
mFontParams.renderingOptions);
}
}
if (int(mRunParams.drawMode) & int(DrawMode::GLYPH_PATH)) {
mRunParams.context->EnsurePathBuilder();
Matrix mat = mRunParams.dt->GetTransform();
mFontParams.scaledFont->CopyGlyphsToBuilder(
buf, mRunParams.context->mPathBuilder,
mRunParams.dt->GetBackendType(), &mat);
}
if ((int(mRunParams.drawMode) &
(int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) ==
int(DrawMode::GLYPH_STROKE)) {
FlushStroke(buf, state);
}
mNumGlyphs = 0;
}
void FlushStroke(gfx::GlyphBuffer& aBuf, gfxContext::AzureState& aState)
{
RefPtr<Path> path =
mFontParams.scaledFont->GetPathForGlyphs(aBuf, mRunParams.dt);
if (mFontParams.contextPaint) {
RefPtr<gfxPattern> strokePattern =
mFontParams.contextPaint->GetStrokePattern(
mRunParams.context->GetDrawTarget(),
mRunParams.context->CurrentMatrix());
if (strokePattern) {
mRunParams.dt->Stroke(path,
*strokePattern->GetPattern(mRunParams.dt),
aState.strokeOptions);
}
}
}
Glyph mGlyphBuffer[GLYPH_BUFFER_SIZE];
unsigned int mNumGlyphs;
#undef GLYPH_BUFFER_SIZE
};
// Bug 674909. When synthetic bolding text by drawing twice, need to
// render using a pixel offset in device pixels, otherwise text
// doesn't appear bolded, it appears as if a bad text shadow exists
// when a non-identity transform exists. Use an offset factor so that
// the second draw occurs at a constant offset in device pixels.
double
gfxFont::CalcXScale(DrawTarget* aDrawTarget)
{
// determine magnitude of a 1px x offset in device space
Size t = aDrawTarget->GetTransform() * Size(1.0, 0.0);
if (t.width == 1.0 && t.height == 0.0) {
// short-circuit the most common case to avoid sqrt() and division
return 1.0;
}
double m = sqrt(t.width * t.width + t.height * t.height);
NS_ASSERTION(m != 0.0, "degenerate transform while synthetic bolding");
if (m == 0.0) {
return 0.0; // effectively disables offset
}
// scale factor so that offsets are 1px in device pixels
return 1.0 / m;
}
static DrawMode
ForcePaintingDrawMode(DrawMode aDrawMode)
{
return aDrawMode == DrawMode::GLYPH_PATH ?
DrawMode(int(DrawMode::GLYPH_FILL) | int(DrawMode::GLYPH_STROKE)) :
aDrawMode;
}
// Draw an individual glyph at a specific location.
// *aPt is the glyph position in appUnits; it is converted to device
// coordinates (devPt) here.
void
gfxFont::DrawOneGlyph(uint32_t aGlyphID, double aAdvance, gfxPoint *aPt,
GlyphBufferAzure& aBuffer, bool *aEmittedGlyphs) const
{
const TextRunDrawParams& runParams(aBuffer.mRunParams);
const FontDrawParams& fontParams(aBuffer.mFontParams);
double glyphX, glyphY;
if (fontParams.isVerticalFont) {
glyphX = aPt->x;
if (runParams.isRTL) {
aPt->y -= aAdvance;
glyphY = aPt->y;
} else {
glyphY = aPt->y;
aPt->y += aAdvance;
}
} else {
glyphY = aPt->y;
if (runParams.isRTL) {
aPt->x -= aAdvance;
glyphX = aPt->x;
} else {
glyphX = aPt->x;
aPt->x += aAdvance;
}
}
gfxPoint devPt(ToDeviceUnits(glyphX, runParams.devPerApp),
ToDeviceUnits(glyphY, runParams.devPerApp));
if (fontParams.haveSVGGlyphs) {
if (!runParams.paintSVGGlyphs) {
return;
}
DrawMode mode = ForcePaintingDrawMode(runParams.drawMode);
if (RenderSVGGlyph(runParams.context, devPt, mode,
aGlyphID, fontParams.contextPaint,
runParams.callbacks, *aEmittedGlyphs)) {
return;
}
}
if (fontParams.haveColorGlyphs &&
RenderColorGlyph(runParams.dt,
fontParams.scaledFont, fontParams.renderingOptions,
fontParams.drawOptions,
fontParams.matInv * gfx::Point(devPt.x, devPt.y),
aGlyphID)) {
return;
}
aBuffer.OutputGlyph(aGlyphID, devPt);
// Synthetic bolding (if required) by multi-striking.
for (int32_t i = 0; i < fontParams.extraStrikes; ++i) {
if (fontParams.isVerticalFont) {
devPt.y += fontParams.synBoldOnePixelOffset;
} else {
devPt.x += fontParams.synBoldOnePixelOffset;
}
aBuffer.OutputGlyph(aGlyphID, devPt);
}
*aEmittedGlyphs = true;
}
// Draw a run of CharacterGlyph records from the given offset in aShapedText.
// Returns true if glyph paths were actually emitted.
bool
gfxFont::DrawGlyphs(gfxShapedText *aShapedText,
uint32_t aOffset, // offset in the textrun
uint32_t aCount, // length of run to draw
gfxPoint *aPt,
const TextRunDrawParams& aRunParams,
const FontDrawParams& aFontParams)
{
bool emittedGlyphs = false;
GlyphBufferAzure buffer(aRunParams, aFontParams);
gfxFloat& inlineCoord = aFontParams.isVerticalFont ? aPt->y : aPt->x;
if (aRunParams.spacing) {
inlineCoord += aRunParams.isRTL ? -aRunParams.spacing[0].mBefore
: aRunParams.spacing[0].mBefore;
}
const gfxShapedText::CompressedGlyph *glyphData =
&aShapedText->GetCharacterGlyphs()[aOffset];
for (uint32_t i = 0; i < aCount; ++i, ++glyphData) {
if (glyphData->IsSimpleGlyph()) {
DrawOneGlyph(glyphData->GetSimpleGlyph(),
glyphData->GetSimpleAdvance(),
aPt, buffer, &emittedGlyphs);
} else {
uint32_t glyphCount = glyphData->GetGlyphCount();
if (glyphCount > 0) {
const gfxShapedText::DetailedGlyph *details =
aShapedText->GetDetailedGlyphs(aOffset + i);
NS_ASSERTION(details, "detailedGlyph should not be missing!");
for (uint32_t j = 0; j < glyphCount; ++j, ++details) {
double advance = details->mAdvance;
if (glyphData->IsMissing()) {
// Default-ignorable chars will have zero advance width;
// we don't have to draw the hexbox for them.
if (aRunParams.drawMode != DrawMode::GLYPH_PATH &&
advance > 0) {
double glyphX = aPt->x;
double glyphY = aPt->y;
if (aRunParams.isRTL) {
if (aFontParams.isVerticalFont) {
glyphY -= advance;
} else {
glyphX -= advance;
}
}
Point pt(Float(ToDeviceUnits(glyphX, aRunParams.devPerApp)),
Float(ToDeviceUnits(glyphY, aRunParams.devPerApp)));
Float advanceDevUnits =
Float(ToDeviceUnits(advance, aRunParams.devPerApp));
Float height = GetMetrics(eHorizontal).maxAscent;
Rect glyphRect = aFontParams.isVerticalFont ?
Rect(pt.x - height / 2, pt.y,
height, advanceDevUnits) :
Rect(pt.x, pt.y - height,
advanceDevUnits, height);
// If there's a fake-italic skew in effect as part
// of the drawTarget's transform, we need to remove
// this before drawing the hexbox. (Bug 983985)
Matrix oldMat;
if (aFontParams.passedInvMatrix) {
oldMat = aRunParams.dt->GetTransform();
aRunParams.dt->SetTransform(
*aFontParams.passedInvMatrix * oldMat);
}
gfxFontMissingGlyphs::DrawMissingGlyph(
details->mGlyphID, glyphRect, *aRunParams.dt,
PatternFromState(aRunParams.context),
aShapedText->GetAppUnitsPerDevUnit());
// Restore the matrix, if we modified it before
// drawing the hexbox.
if (aFontParams.passedInvMatrix) {
aRunParams.dt->SetTransform(oldMat);
}
}
} else {
gfxPoint glyphXY(*aPt);
if (aFontParams.isVerticalFont) {
glyphXY.x += details->mYOffset;
glyphXY.y += details->mXOffset;
} else {
glyphXY.x += details->mXOffset;
glyphXY.y += details->mYOffset;
}
DrawOneGlyph(details->mGlyphID, advance, &glyphXY,
buffer, &emittedGlyphs);
}
inlineCoord += aRunParams.isRTL ? -advance : advance;
}
}
}
if (aRunParams.spacing) {
double space = aRunParams.spacing[i].mAfter;
if (i + 1 < aCount) {
space += aRunParams.spacing[i + 1].mBefore;
}
inlineCoord += aRunParams.isRTL ? -space : space;
}
}
return emittedGlyphs;
}
// This method is mostly parallel to DrawGlyphs.
void
gfxFont::DrawEmphasisMarks(gfxTextRun* aShapedText, gfxPoint* aPt,
uint32_t aOffset, uint32_t aCount,
const EmphasisMarkDrawParams& aParams)
{
gfxFloat& inlineCoord = aParams.isVertical ? aPt->y : aPt->x;
uint32_t markLength = aParams.mark->GetLength();
gfxFloat clusterStart = -std::numeric_limits<gfxFloat>::infinity();
bool shouldDrawEmphasisMark = false;
for (uint32_t i = 0, idx = aOffset; i < aCount; ++i, ++idx) {
if (aParams.spacing) {
inlineCoord += aParams.direction * aParams.spacing[i].mBefore;
}
if (aShapedText->IsClusterStart(idx) ||
clusterStart == -std::numeric_limits<gfxFloat>::infinity()) {
clusterStart = inlineCoord;
}
if (aShapedText->CharMayHaveEmphasisMark(idx)) {
shouldDrawEmphasisMark = true;
}
inlineCoord += aParams.direction * aShapedText->GetAdvanceForGlyph(idx);
if (shouldDrawEmphasisMark &&
(i + 1 == aCount || aShapedText->IsClusterStart(idx + 1))) {
gfxFloat clusterAdvance = inlineCoord - clusterStart;
// Move the coord backward to get the needed start point.
gfxFloat delta = (clusterAdvance + aParams.advance) / 2;
inlineCoord -= delta;
aParams.mark->Draw(aParams.context, *aPt, DrawMode::GLYPH_FILL,
0, markLength, nullptr, nullptr, nullptr);
inlineCoord += delta;
shouldDrawEmphasisMark = false;
}
if (aParams.spacing) {
inlineCoord += aParams.direction * aParams.spacing[i].mAfter;
}
}
}
void
gfxFont::Draw(gfxTextRun *aTextRun, uint32_t aStart, uint32_t aEnd,
gfxPoint *aPt, const TextRunDrawParams& aRunParams,
uint16_t aOrientation)
{
NS_ASSERTION(aRunParams.drawMode == DrawMode::GLYPH_PATH ||
!(int(aRunParams.drawMode) & int(DrawMode::GLYPH_PATH)),
"GLYPH_PATH cannot be used with GLYPH_FILL, GLYPH_STROKE or GLYPH_STROKE_UNDERNEATH");
if (aStart >= aEnd) {
return;
}
FontDrawParams fontParams;
fontParams.scaledFont = GetScaledFont(aRunParams.dt);
if (!fontParams.scaledFont) {
return;
}
fontParams.haveSVGGlyphs = GetFontEntry()->TryGetSVGData(this);
fontParams.haveColorGlyphs = GetFontEntry()->TryGetColorGlyphs();
fontParams.contextPaint = aRunParams.runContextPaint;
fontParams.isVerticalFont =
aOrientation == gfxTextRunFactory::TEXT_ORIENT_VERTICAL_UPRIGHT;
bool sideways = false;
gfxPoint origPt = *aPt;
if (aRunParams.isVerticalRun && !fontParams.isVerticalFont) {
sideways = true;
aRunParams.context->Save();
gfxPoint p(aPt->x * aRunParams.devPerApp,
aPt->y * aRunParams.devPerApp);
const Metrics& metrics = GetMetrics(eHorizontal);
// Get a matrix we can use to draw the (horizontally-shaped) textrun
// with 90-degree CW rotation.
const gfxFloat
rotation = (aOrientation ==
gfxTextRunFactory::TEXT_ORIENT_VERTICAL_SIDEWAYS_LEFT)
? -M_PI / 2.0 : M_PI / 2.0;
gfxMatrix mat =
aRunParams.context->CurrentMatrix().
Translate(p). // translate origin for rotation
Rotate(rotation). // turn 90deg CCW (sideways-left) or CW (*-right)
Translate(-p); // undo the translation
// If we're drawing rotated horizontal text for an element styled
// text-orientation:mixed, the dominant baseline will be vertical-
// centered. So in this case, we need to adjust the position so that
// the rotated horizontal text (which uses an alphabetic baseline) will
// look OK when juxtaposed with upright glyphs (rendered on a centered
// vertical baseline). The adjustment here is somewhat ad hoc; we
// should eventually look for baseline tables[1] in the fonts and use
// those if available.
// [1] See http://www.microsoft.com/typography/otspec/base.htm
if (aTextRun->UseCenterBaseline()) {
gfxPoint baseAdj(0, (metrics.emAscent - metrics.emDescent) / 2);
mat.Translate(baseAdj);
}
aRunParams.context->SetMatrix(mat);
}
nsAutoPtr<gfxTextContextPaint> contextPaint;
if (fontParams.haveSVGGlyphs && !fontParams.contextPaint) {
// If no pattern is specified for fill, use the current pattern
NS_ASSERTION((int(aRunParams.drawMode) & int(DrawMode::GLYPH_STROKE)) == 0,
"no pattern supplied for stroking text");
RefPtr<gfxPattern> fillPattern = aRunParams.context->GetPattern();
contextPaint =
new SimpleTextContextPaint(fillPattern, nullptr,
aRunParams.context->CurrentMatrix());
fontParams.contextPaint = contextPaint;
}
// Synthetic-bold strikes are each offset one device pixel in run direction.
// (these values are only needed if IsSyntheticBold() is true)
if (IsSyntheticBold()) {
double xscale = CalcXScale(aRunParams.context->GetDrawTarget());
fontParams.synBoldOnePixelOffset = aRunParams.direction * xscale;
if (xscale != 0.0) {
// use as many strikes as needed for the the increased advance
fontParams.extraStrikes =
std::max(1, NS_lroundf(GetSyntheticBoldOffset() / xscale));
}
} else {
fontParams.synBoldOnePixelOffset = 0;
fontParams.extraStrikes = 0;
}
bool oldSubpixelAA = aRunParams.dt->GetPermitSubpixelAA();
if (!AllowSubpixelAA()) {
aRunParams.dt->SetPermitSubpixelAA(false);
}
Matrix mat;
Matrix oldMat = aRunParams.dt->GetTransform();
// This is nullptr when we have inverse-transformed glyphs and we need
// to transform the Brush inside flush.
fontParams.passedInvMatrix = nullptr;
fontParams.renderingOptions = GetGlyphRenderingOptions(&aRunParams);
fontParams.drawOptions.mAntialiasMode = Get2DAAMode(mAntialiasOption);
// The cairo DrawTarget backend uses the cairo_scaled_font directly
// and so has the font skew matrix applied already.
if (mScaledFont &&
aRunParams.dt->GetBackendType() != BackendType::CAIRO) {
cairo_matrix_t matrix;
cairo_scaled_font_get_font_matrix(mScaledFont, &matrix);
if (matrix.xy != 0) {
// If this matrix applies a skew, which can happen when drawing
// oblique fonts, we will set the DrawTarget matrix to apply the
// skew. We'll need to move the glyphs by the inverse of the skew to
// get the glyphs positioned correctly in the new device space
// though, since the font matrix should only be applied to drawing
// the glyphs, and not to their position.
mat = Matrix(matrix.xx, matrix.yx,
matrix.xy, matrix.yy,
matrix.x0, matrix.y0);
mat._11 = mat._22 = 1.0;
mat._21 /= GetAdjustedSize();
aRunParams.dt->SetTransform(mat * oldMat);
fontParams.matInv = mat;
fontParams.matInv.Invert();
fontParams.passedInvMatrix = &fontParams.matInv;
}
}
gfxFloat& baseline = fontParams.isVerticalFont ? aPt->x : aPt->y;
gfxFloat origBaseline = baseline;
if (mStyle.baselineOffset != 0.0) {
baseline +=
mStyle.baselineOffset * aTextRun->GetAppUnitsPerDevUnit();
}
bool emittedGlyphs =
DrawGlyphs(aTextRun, aStart, aEnd - aStart, aPt,
aRunParams, fontParams);
baseline = origBaseline;
if (aRunParams.callbacks && emittedGlyphs) {
aRunParams.callbacks->NotifyGlyphPathEmitted();
}
aRunParams.dt->SetTransform(oldMat);
aRunParams.dt->SetPermitSubpixelAA(oldSubpixelAA);
if (sideways) {
aRunParams.context->Restore();
// adjust updated aPt to account for the transform we were using
gfxFloat advance = aPt->x - origPt.x;
if (aOrientation ==
gfxTextRunFactory::TEXT_ORIENT_VERTICAL_SIDEWAYS_LEFT) {
*aPt = gfxPoint(origPt.x, origPt.y - advance);
} else {
*aPt = gfxPoint(origPt.x, origPt.y + advance);
}
}
}
bool
gfxFont::RenderSVGGlyph(gfxContext *aContext, gfxPoint aPoint, DrawMode aDrawMode,
uint32_t aGlyphId, gfxTextContextPaint *aContextPaint) const
{
if (!GetFontEntry()->HasSVGGlyph(aGlyphId)) {
return false;
}
const gfxFloat devUnitsPerSVGUnit =
GetAdjustedSize() / GetFontEntry()->UnitsPerEm();
gfxContextMatrixAutoSaveRestore matrixRestore(aContext);
aContext->Save();
aContext->SetMatrix(
aContext->CurrentMatrix().Translate(aPoint.x, aPoint.y).
Scale(devUnitsPerSVGUnit, devUnitsPerSVGUnit));
aContextPaint->InitStrokeGeometry(aContext, devUnitsPerSVGUnit);
bool rv = GetFontEntry()->RenderSVGGlyph(aContext, aGlyphId,
int(aDrawMode), aContextPaint);
aContext->Restore();
aContext->NewPath();
return rv;
}
bool
gfxFont::RenderSVGGlyph(gfxContext *aContext, gfxPoint aPoint, DrawMode aDrawMode,
uint32_t aGlyphId, gfxTextContextPaint *aContextPaint,
gfxTextRunDrawCallbacks *aCallbacks,
bool& aEmittedGlyphs) const
{
if (aCallbacks && aEmittedGlyphs) {
aCallbacks->NotifyGlyphPathEmitted();
aEmittedGlyphs = false;
}
return RenderSVGGlyph(aContext, aPoint, aDrawMode, aGlyphId, aContextPaint);
}
bool
gfxFont::RenderColorGlyph(DrawTarget* aDrawTarget,
mozilla::gfx::ScaledFont* scaledFont,
GlyphRenderingOptions* aRenderingOptions,
mozilla::gfx::DrawOptions aDrawOptions,
const mozilla::gfx::Point& aPoint,
uint32_t aGlyphId) const
{
nsAutoTArray<uint16_t, 8> layerGlyphs;
nsAutoTArray<mozilla::gfx::Color, 8> layerColors;
if (!GetFontEntry()->GetColorLayersInfo(aGlyphId, layerGlyphs, layerColors)) {
return false;
}
for (uint32_t layerIndex = 0; layerIndex < layerGlyphs.Length();
layerIndex++) {
Glyph glyph;
glyph.mIndex = layerGlyphs[layerIndex];
glyph.mPosition = aPoint;
mozilla::gfx::GlyphBuffer buffer;
buffer.mGlyphs = &glyph;
buffer.mNumGlyphs = 1;
aDrawTarget->FillGlyphs(scaledFont, buffer,
ColorPattern(layerColors[layerIndex]),
aDrawOptions, aRenderingOptions);
}
return true;
}
static void
UnionRange(gfxFloat aX, gfxFloat* aDestMin, gfxFloat* aDestMax)
{
*aDestMin = std::min(*aDestMin, aX);
*aDestMax = std::max(*aDestMax, aX);
}
// We get precise glyph extents if the textrun creator requested them, or
// if the font is a user font --- in which case the author may be relying
// on overflowing glyphs.
static bool
NeedsGlyphExtents(gfxFont *aFont, gfxTextRun *aTextRun)
{
return (aTextRun->GetFlags() & gfxTextRunFactory::TEXT_NEED_BOUNDING_BOX) ||
aFont->GetFontEntry()->IsUserFont();
}
bool
gfxFont::IsSpaceGlyphInvisible(gfxContext *aRefContext, gfxTextRun *aTextRun)
{
if (!mFontEntry->mSpaceGlyphIsInvisibleInitialized &&
GetAdjustedSize() >= 1.0) {
gfxGlyphExtents *extents =
GetOrCreateGlyphExtents(aTextRun->GetAppUnitsPerDevUnit());
gfxRect glyphExtents;
mFontEntry->mSpaceGlyphIsInvisible =
extents->GetTightGlyphExtentsAppUnits(this, aRefContext,
GetSpaceGlyph(), &glyphExtents) &&
glyphExtents.IsEmpty();
mFontEntry->mSpaceGlyphIsInvisibleInitialized = true;
}
return mFontEntry->mSpaceGlyphIsInvisible;
}
gfxFont::RunMetrics
gfxFont::Measure(gfxTextRun *aTextRun,
uint32_t aStart, uint32_t aEnd,
BoundingBoxType aBoundingBoxType,
gfxContext *aRefContext,
Spacing *aSpacing,
uint16_t aOrientation)
{
// If aBoundingBoxType is TIGHT_HINTED_OUTLINE_EXTENTS
// and the underlying cairo font may be antialiased,
// we need to create a copy in order to avoid getting cached extents.
// This is only used by MathML layout at present.
if (aBoundingBoxType == TIGHT_HINTED_OUTLINE_EXTENTS &&
mAntialiasOption != kAntialiasNone) {
if (!mNonAAFont) {
mNonAAFont = CopyWithAntialiasOption(kAntialiasNone);
}
// if font subclass doesn't implement CopyWithAntialiasOption(),
// it will return null and we'll proceed to use the existing font
if (mNonAAFont) {
return mNonAAFont->Measure(aTextRun, aStart, aEnd,
TIGHT_HINTED_OUTLINE_EXTENTS,
aRefContext, aSpacing, aOrientation);
}
}
const int32_t appUnitsPerDevUnit = aTextRun->GetAppUnitsPerDevUnit();
// Current position in appunits
gfxFont::Orientation orientation =
aOrientation == gfxTextRunFactory::TEXT_ORIENT_VERTICAL_UPRIGHT
? eVertical : eHorizontal;
const gfxFont::Metrics& fontMetrics = GetMetrics(orientation);
gfxFloat baselineOffset = 0;
if (aTextRun->UseCenterBaseline() && orientation == eHorizontal) {
// For a horizontal font being used in vertical writing mode with
// text-orientation:mixed, the overall metrics we're accumulating
// will be aimed at a center baseline. But this font's metrics were
// based on the alphabetic baseline. So we compute a baseline offset
// that will be applied to ascent/descent values and glyph rects
// to effectively shift them relative to the baseline.
// XXX Eventually we should probably use the BASE table, if present.
// But it usually isn't, so we need an ad hoc adjustment for now.
baselineOffset = appUnitsPerDevUnit *
(fontMetrics.emAscent - fontMetrics.emDescent) / 2;
}
RunMetrics metrics;
metrics.mAscent = fontMetrics.maxAscent * appUnitsPerDevUnit;
metrics.mDescent = fontMetrics.maxDescent * appUnitsPerDevUnit;
if (aStart == aEnd) {
// exit now before we look at aSpacing[0], which is undefined
metrics.mAscent -= baselineOffset;
metrics.mDescent += baselineOffset;
metrics.mBoundingBox = gfxRect(0, -metrics.mAscent,
0, metrics.mAscent + metrics.mDescent);
return metrics;
}
gfxFloat advanceMin = 0, advanceMax = 0;
const gfxTextRun::CompressedGlyph *charGlyphs = aTextRun->GetCharacterGlyphs();
bool isRTL = aTextRun->IsRightToLeft();
double direction = aTextRun->GetDirection();
bool needsGlyphExtents = NeedsGlyphExtents(this, aTextRun);
gfxGlyphExtents *extents =
((aBoundingBoxType == LOOSE_INK_EXTENTS &&
!needsGlyphExtents &&
!aTextRun->HasDetailedGlyphs()) ||
(MOZ_UNLIKELY(GetStyle()->sizeAdjust == 0.0)) ||
(MOZ_UNLIKELY(GetStyle()->size == 0))) ? nullptr
: GetOrCreateGlyphExtents(aTextRun->GetAppUnitsPerDevUnit());
double x = 0;
if (aSpacing) {
x += direction*aSpacing[0].mBefore;
}
uint32_t spaceGlyph = GetSpaceGlyph();
bool allGlyphsInvisible = true;
uint32_t i;
for (i = aStart; i < aEnd; ++i) {
const gfxTextRun::CompressedGlyph *glyphData = &charGlyphs[i];
if (glyphData->IsSimpleGlyph()) {
double advance = glyphData->GetSimpleAdvance();
uint32_t glyphIndex = glyphData->GetSimpleGlyph();
if (glyphIndex != spaceGlyph ||
!IsSpaceGlyphInvisible(aRefContext, aTextRun)) {
allGlyphsInvisible = false;
}
// Only get the real glyph horizontal extent if we were asked
// for the tight bounding box or we're in quality mode
if ((aBoundingBoxType != LOOSE_INK_EXTENTS || needsGlyphExtents) &&
extents){
uint16_t extentsWidth = extents->GetContainedGlyphWidthAppUnits(glyphIndex);
if (extentsWidth != gfxGlyphExtents::INVALID_WIDTH &&
aBoundingBoxType == LOOSE_INK_EXTENTS) {
UnionRange(x, &advanceMin, &advanceMax);
UnionRange(x + direction*extentsWidth, &advanceMin, &advanceMax);
} else {
gfxRect glyphRect;
if (!extents->GetTightGlyphExtentsAppUnits(this,
aRefContext, glyphIndex, &glyphRect)) {
glyphRect = gfxRect(0, metrics.mBoundingBox.Y(),
advance, metrics.mBoundingBox.Height());
}
if (orientation == eVertical) {
Swap(glyphRect.x, glyphRect.y);
Swap(glyphRect.width, glyphRect.height);
}
if (isRTL) {
glyphRect -= gfxPoint(advance, 0);
}
glyphRect += gfxPoint(x, 0);
metrics.mBoundingBox = metrics.mBoundingBox.Union(glyphRect);
}
}
x += direction*advance;
} else {
allGlyphsInvisible = false;
uint32_t glyphCount = glyphData->GetGlyphCount();
if (glyphCount > 0) {
const gfxTextRun::DetailedGlyph *details =
aTextRun->GetDetailedGlyphs(i);
NS_ASSERTION(details != nullptr,
"detailedGlyph record should not be missing!");
uint32_t j;
for (j = 0; j < glyphCount; ++j, ++details) {
uint32_t glyphIndex = details->mGlyphID;
gfxPoint glyphPt(x + details->mXOffset, details->mYOffset);
double advance = details->mAdvance;
gfxRect glyphRect;
if (glyphData->IsMissing() || !extents ||
!extents->GetTightGlyphExtentsAppUnits(this,
aRefContext, glyphIndex, &glyphRect)) {
// We might have failed to get glyph extents due to
// OOM or something
glyphRect = gfxRect(0, -metrics.mAscent,
advance, metrics.mAscent + metrics.mDescent);
}
if (orientation == eVertical) {
Swap(glyphRect.x, glyphRect.y);
Swap(glyphRect.width, glyphRect.height);
}
if (isRTL) {
glyphRect -= gfxPoint(advance, 0);
}
glyphRect += glyphPt;
metrics.mBoundingBox = metrics.mBoundingBox.Union(glyphRect);
x += direction*advance;
}
}
}
// Every other glyph type is ignored
if (aSpacing) {
double space = aSpacing[i - aStart].mAfter;
if (i + 1 < aEnd) {
space += aSpacing[i + 1 - aStart].mBefore;
}
x += direction*space;
}
}
if (allGlyphsInvisible) {
metrics.mBoundingBox.SetEmpty();
} else {
if (aBoundingBoxType == LOOSE_INK_EXTENTS) {
UnionRange(x, &advanceMin, &advanceMax);
gfxRect fontBox(advanceMin, -metrics.mAscent,
advanceMax - advanceMin, metrics.mAscent + metrics.mDescent);
metrics.mBoundingBox = metrics.mBoundingBox.Union(fontBox);
}
if (isRTL) {
metrics.mBoundingBox -= gfxPoint(x, 0);
}
}
// If the font may be rendered with a fake-italic effect, we need to allow
// for the top-right of the glyphs being skewed to the right, and the
// bottom-left being skewed further left.
if (mStyle.style != NS_FONT_STYLE_NORMAL &&
mFontEntry->IsUpright() &&
mStyle.allowSyntheticStyle) {
gfxFloat extendLeftEdge =
ceil(OBLIQUE_SKEW_FACTOR * metrics.mBoundingBox.YMost());
gfxFloat extendRightEdge =
ceil(OBLIQUE_SKEW_FACTOR * -metrics.mBoundingBox.y);
metrics.mBoundingBox.width += extendLeftEdge + extendRightEdge;
metrics.mBoundingBox.x -= extendLeftEdge;
}
if (baselineOffset != 0) {
metrics.mAscent -= baselineOffset;
metrics.mDescent += baselineOffset;
metrics.mBoundingBox.y += baselineOffset;
}
metrics.mAdvanceWidth = x*direction;
return metrics;
}
void
gfxFont::AgeCachedWords()
{
if (mWordCache) {
for (auto it = mWordCache->Iter(); !it.Done(); it.Next()) {
CacheHashEntry *entry = it.Get();
if (!entry->mShapedWord) {
NS_ASSERTION(entry->mShapedWord,
"cache entry has no gfxShapedWord!");
it.Remove();
} else if (entry->mShapedWord->IncrementAge() ==
kShapedWordCacheMaxAge) {
it.Remove();
}
}
}
}
void
gfxFont::NotifyGlyphsChanged()
{
uint32_t i, count = mGlyphExtentsArray.Length();
for (i = 0; i < count; ++i) {
// Flush cached extents array
mGlyphExtentsArray[i]->NotifyGlyphsChanged();
}
if (mGlyphChangeObservers) {
for (auto it = mGlyphChangeObservers->Iter(); !it.Done(); it.Next()) {
it.Get()->GetKey()->NotifyGlyphsChanged();
}
}
}
// If aChar is a "word boundary" for shaped-word caching purposes, return it;
// else return 0.
static char16_t
IsBoundarySpace(char16_t aChar, char16_t aNextChar)
{
if ((aChar == ' ' || aChar == 0x00A0) && !IsClusterExtender(aNextChar)) {
return aChar;
}
return 0;
}
#ifdef __GNUC__
#define GFX_MAYBE_UNUSED __attribute__((unused))
#else
#define GFX_MAYBE_UNUSED
#endif
template<typename T>
gfxShapedWord*
gfxFont::GetShapedWord(gfxContext *aContext,
const T *aText,
uint32_t aLength,
uint32_t aHash,
int32_t aRunScript,
bool aVertical,
int32_t aAppUnitsPerDevUnit,
uint32_t aFlags,
gfxTextPerfMetrics *aTextPerf GFX_MAYBE_UNUSED)
{
// if the cache is getting too big, flush it and start over
uint32_t wordCacheMaxEntries =
gfxPlatform::GetPlatform()->WordCacheMaxEntries();
if (mWordCache->Count() > wordCacheMaxEntries) {
NS_WARNING("flushing shaped-word cache");
ClearCachedWords();
}
// if there's a cached entry for this word, just return it
CacheHashKey key(aText, aLength, aHash,
aRunScript,
aAppUnitsPerDevUnit,
aFlags);
CacheHashEntry *entry = mWordCache->PutEntry(key);
if (!entry) {
NS_WARNING("failed to create word cache entry - expect missing text");
return nullptr;
}
gfxShapedWord *sw = entry->mShapedWord;
bool isContent = !mStyle.systemFont;
if (sw) {
sw->ResetAge();
Telemetry::Accumulate((isContent ? Telemetry::WORD_CACHE_HITS_CONTENT :
Telemetry::WORD_CACHE_HITS_CHROME),
aLength);
#ifndef RELEASE_BUILD
if (aTextPerf) {
aTextPerf->current.wordCacheHit++;
}
#endif
return sw;
}
Telemetry::Accumulate((isContent ? Telemetry::WORD_CACHE_MISSES_CONTENT :
Telemetry::WORD_CACHE_MISSES_CHROME),
aLength);
#ifndef RELEASE_BUILD
if (aTextPerf) {
aTextPerf->current.wordCacheMiss++;
}
#endif
sw = entry->mShapedWord = gfxShapedWord::Create(aText, aLength,
aRunScript,
aAppUnitsPerDevUnit,
aFlags);
if (!sw) {
NS_WARNING("failed to create gfxShapedWord - expect missing text");
return nullptr;
}
DebugOnly<bool> ok =
ShapeText(aContext, aText, 0, aLength, aRunScript, aVertical, sw);
NS_WARN_IF_FALSE(ok, "failed to shape word - expect garbled text");
return sw;
}
bool
gfxFont::CacheHashEntry::KeyEquals(const KeyTypePointer aKey) const
{
const gfxShapedWord *sw = mShapedWord;
if (!sw) {
return false;
}
if (sw->GetLength() != aKey->mLength ||
sw->GetFlags() != aKey->mFlags ||
sw->GetAppUnitsPerDevUnit() != aKey->mAppUnitsPerDevUnit ||
sw->Script() != aKey->mScript) {
return false;
}
if (sw->TextIs8Bit()) {
if (aKey->mTextIs8Bit) {
return (0 == memcmp(sw->Text8Bit(), aKey->mText.mSingle,
aKey->mLength * sizeof(uint8_t)));
}
// The key has 16-bit text, even though all the characters are < 256,
// so the TEXT_IS_8BIT flag was set and the cached ShapedWord we're
// comparing with will have 8-bit text.
const uint8_t *s1 = sw->Text8Bit();
const char16_t *s2 = aKey->mText.mDouble;
const char16_t *s2end = s2 + aKey->mLength;
while (s2 < s2end) {
if (*s1++ != *s2++) {
return false;
}
}
return true;
}
NS_ASSERTION((aKey->mFlags & gfxTextRunFactory::TEXT_IS_8BIT) == 0 &&
!aKey->mTextIs8Bit, "didn't expect 8-bit text here");
return (0 == memcmp(sw->TextUnicode(), aKey->mText.mDouble,
aKey->mLength * sizeof(char16_t)));
}
bool
gfxFont::ShapeText(gfxContext *aContext,
const uint8_t *aText,
uint32_t aOffset,
uint32_t aLength,
int32_t aScript,
bool aVertical,
gfxShapedText *aShapedText)
{
nsDependentCSubstring ascii((const char*)aText, aLength);
nsAutoString utf16;
AppendASCIItoUTF16(ascii, utf16);
if (utf16.Length() != aLength) {
return false;
}
return ShapeText(aContext, utf16.BeginReading(), aOffset, aLength,
aScript, aVertical, aShapedText);
}
bool
gfxFont::ShapeText(gfxContext *aContext,
const char16_t *aText,
uint32_t aOffset,
uint32_t aLength,
int32_t aScript,
bool aVertical,
gfxShapedText *aShapedText)
{
bool ok = false;
// XXX Currently, we do all vertical shaping through harfbuzz.
// Vertical graphite support may be wanted as a future enhancement.
if (FontCanSupportGraphite() && !aVertical) {
if (gfxPlatform::GetPlatform()->UseGraphiteShaping()) {
if (!mGraphiteShaper) {
mGraphiteShaper = new gfxGraphiteShaper(this);
}
ok = mGraphiteShaper->ShapeText(aContext, aText, aOffset, aLength,
aScript, aVertical, aShapedText);
}
}
if (!ok) {
if (!mHarfBuzzShaper) {
mHarfBuzzShaper = new gfxHarfBuzzShaper(this);
}
ok = mHarfBuzzShaper->ShapeText(aContext, aText, aOffset, aLength,
aScript, aVertical, aShapedText);
}
NS_WARN_IF_FALSE(ok, "shaper failed, expect scrambled or missing text");
PostShapingFixup(aContext->GetDrawTarget(), aText, aOffset, aLength,
aVertical, aShapedText);
return ok;
}
void
gfxFont::PostShapingFixup(DrawTarget* aDrawTarget,
const char16_t* aText,
uint32_t aOffset,
uint32_t aLength,
bool aVertical,
gfxShapedText* aShapedText)
{
if (IsSyntheticBold()) {
const Metrics& metrics =
GetMetrics(aVertical ? eVertical : eHorizontal);
if (metrics.maxAdvance > metrics.aveCharWidth) {
float synBoldOffset =
GetSyntheticBoldOffset() * CalcXScale(aDrawTarget);
aShapedText->AdjustAdvancesForSyntheticBold(synBoldOffset,
aOffset, aLength);
}
}
}
#define MAX_SHAPING_LENGTH 32760 // slightly less than 32K, trying to avoid
// over-stressing platform shapers
#define BACKTRACK_LIMIT 16 // backtrack this far looking for a good place
// to split into fragments for separate shaping
template<typename T>
bool
gfxFont::ShapeFragmentWithoutWordCache(gfxContext *aContext,
const T *aText,
uint32_t aOffset,
uint32_t aLength,
int32_t aScript,
bool aVertical,
gfxTextRun *aTextRun)
{
aTextRun->SetupClusterBoundaries(aOffset, aText, aLength);
bool ok = true;
while (ok && aLength > 0) {
uint32_t fragLen = aLength;
// limit the length of text we pass to shapers in a single call
if (fragLen > MAX_SHAPING_LENGTH) {
fragLen = MAX_SHAPING_LENGTH;
// in the 8-bit case, there are no multi-char clusters,
// so we don't need to do this check
if (sizeof(T) == sizeof(char16_t)) {
uint32_t i;
for (i = 0; i < BACKTRACK_LIMIT; ++i) {
if (aTextRun->IsClusterStart(aOffset + fragLen - i)) {
fragLen -= i;
break;
}
}
if (i == BACKTRACK_LIMIT) {
// if we didn't find any cluster start while backtracking,
// just check that we're not in the middle of a surrogate
// pair; back up by one code unit if we are.
if (NS_IS_LOW_SURROGATE(aText[fragLen]) &&
NS_IS_HIGH_SURROGATE(aText[fragLen - 1])) {
--fragLen;
}
}
}
}
ok = ShapeText(aContext, aText, aOffset, fragLen, aScript, aVertical,
aTextRun);
aText += fragLen;
aOffset += fragLen;
aLength -= fragLen;
}
return ok;
}
// Check if aCh is an unhandled control character that should be displayed
// as a hexbox rather than rendered by some random font on the system.
// We exclude \r as stray &#13;s are rather common (bug 941940).
// Note that \n and \t don't come through here, as they have specific
// meanings that have already been handled.
static bool
IsInvalidControlChar(uint32_t aCh)
{
return aCh != '\r' && ((aCh & 0x7f) < 0x20 || aCh == 0x7f);
}
template<typename T>
bool
gfxFont::ShapeTextWithoutWordCache(gfxContext *aContext,
const T *aText,
uint32_t aOffset,
uint32_t aLength,
int32_t aScript,
bool aVertical,
gfxTextRun *aTextRun)
{
uint32_t fragStart = 0;
bool ok = true;
for (uint32_t i = 0; i <= aLength && ok; ++i) {
T ch = (i < aLength) ? aText[i] : '\n';
bool invalid = gfxFontGroup::IsInvalidChar(ch);
uint32_t length = i - fragStart;
// break into separate fragments when we hit an invalid char
if (!invalid) {
continue;
}
if (length > 0) {
ok = ShapeFragmentWithoutWordCache(aContext, aText + fragStart,
aOffset + fragStart, length,
aScript, aVertical, aTextRun);
}
if (i == aLength) {
break;
}
// fragment was terminated by an invalid char: skip it,
// unless it's a control char that we want to show as a hexbox,
// but record where TAB or NEWLINE occur
if (ch == '\t') {
aTextRun->SetIsTab(aOffset + i);
} else if (ch == '\n') {
aTextRun->SetIsNewline(aOffset + i);
} else if (IsInvalidControlChar(ch) &&
!(aTextRun->GetFlags() & gfxTextRunFactory::TEXT_HIDE_CONTROL_CHARACTERS)) {
if (GetFontEntry()->IsUserFont() && HasCharacter(ch)) {
ShapeFragmentWithoutWordCache(aContext, aText + i,
aOffset + i, 1,
aScript, aVertical, aTextRun);
} else {
aTextRun->SetMissingGlyph(aOffset + i, ch, this);
}
}
fragStart = i + 1;
}
NS_WARN_IF_FALSE(ok, "failed to shape text - expect garbled text");
return ok;
}
#ifndef RELEASE_BUILD
#define TEXT_PERF_INCR(tp, m) (tp ? (tp)->current.m++ : 0)
#else
#define TEXT_PERF_INCR(tp, m)
#endif
inline static bool IsChar8Bit(uint8_t /*aCh*/) { return true; }
inline static bool IsChar8Bit(char16_t aCh) { return aCh < 0x100; }
inline static bool HasSpaces(const uint8_t *aString, uint32_t aLen)
{
return memchr(aString, 0x20, aLen) != nullptr;
}
inline static bool HasSpaces(const char16_t *aString, uint32_t aLen)
{
for (const char16_t *ch = aString; ch < aString + aLen; ch++) {
if (*ch == 0x20) {
return true;
}
}
return false;
}
template<typename T>
bool
gfxFont::SplitAndInitTextRun(gfxContext *aContext,
gfxTextRun *aTextRun,
const T *aString, // text for this font run
uint32_t aRunStart, // position in the textrun
uint32_t aRunLength,
int32_t aRunScript,
bool aVertical)
{
if (aRunLength == 0) {
return true;
}
gfxTextPerfMetrics *tp = nullptr;
#ifndef RELEASE_BUILD
tp = aTextRun->GetFontGroup()->GetTextPerfMetrics();
if (tp) {
if (mStyle.systemFont) {
tp->current.numChromeTextRuns++;
} else {
tp->current.numContentTextRuns++;
}
tp->current.numChars += aRunLength;
if (aRunLength > tp->current.maxTextRunLen) {
tp->current.maxTextRunLen = aRunLength;
}
}
#endif
uint32_t wordCacheCharLimit =
gfxPlatform::GetPlatform()->WordCacheCharLimit();
// If spaces can participate in shaping (e.g. within lookups for automatic
// fractions), need to shape without using the word cache which segments
// textruns on space boundaries. Word cache can be used if the textrun
// is short enough to fit in the word cache and it lacks spaces.
if (SpaceMayParticipateInShaping(aRunScript)) {
if (aRunLength > wordCacheCharLimit ||
HasSpaces(aString, aRunLength)) {
TEXT_PERF_INCR(tp, wordCacheSpaceRules);
return ShapeTextWithoutWordCache(aContext, aString,
aRunStart, aRunLength,
aRunScript, aVertical,
aTextRun);
}
}
InitWordCache();
// the only flags we care about for ShapedWord construction/caching
uint32_t flags = aTextRun->GetFlags();
flags &= (gfxTextRunFactory::TEXT_IS_RTL |
gfxTextRunFactory::TEXT_DISABLE_OPTIONAL_LIGATURES |
gfxTextRunFactory::TEXT_USE_MATH_SCRIPT |
gfxTextRunFactory::TEXT_ORIENT_MASK);
if (sizeof(T) == sizeof(uint8_t)) {
flags |= gfxTextRunFactory::TEXT_IS_8BIT;
}
uint32_t wordStart = 0;
uint32_t hash = 0;
bool wordIs8Bit = true;
int32_t appUnitsPerDevUnit = aTextRun->GetAppUnitsPerDevUnit();
T nextCh = aString[0];
for (uint32_t i = 0; i <= aRunLength; ++i) {
T ch = nextCh;
nextCh = (i < aRunLength - 1) ? aString[i + 1] : '\n';
T boundary = IsBoundarySpace(ch, nextCh);
bool invalid = !boundary && gfxFontGroup::IsInvalidChar(ch);
uint32_t length = i - wordStart;
// break into separate ShapedWords when we hit an invalid char,
// or a boundary space (always handled individually),
// or the first non-space after a space
if (!boundary && !invalid) {
if (!IsChar8Bit(ch)) {
wordIs8Bit = false;
}
// include this character in the hash, and move on to next
hash = gfxShapedWord::HashMix(hash, ch);
continue;
}
// We've decided to break here (i.e. we're at the end of a "word");
// shape the word and add it to the textrun.
// For words longer than the limit, we don't use the
// font's word cache but just shape directly into the textrun.
if (length > wordCacheCharLimit) {
TEXT_PERF_INCR(tp, wordCacheLong);
bool ok = ShapeFragmentWithoutWordCache(aContext,
aString + wordStart,
aRunStart + wordStart,
length,
aRunScript,
aVertical,
aTextRun);
if (!ok) {
return false;
}
} else if (length > 0) {
uint32_t wordFlags = flags;
// in the 8-bit version of this method, TEXT_IS_8BIT was
// already set as part of |flags|, so no need for a per-word
// adjustment here
if (sizeof(T) == sizeof(char16_t)) {
if (wordIs8Bit) {
wordFlags |= gfxTextRunFactory::TEXT_IS_8BIT;
}
}
gfxShapedWord *sw = GetShapedWord(aContext,
aString + wordStart, length,
hash, aRunScript, aVertical,
appUnitsPerDevUnit,
wordFlags, tp);
if (sw) {
aTextRun->CopyGlyphDataFrom(sw, aRunStart + wordStart);
} else {
return false; // failed, presumably out of memory?
}
}
if (boundary) {
// word was terminated by a space: add that to the textrun
uint16_t orientation = flags & gfxTextRunFactory::TEXT_ORIENT_MASK;
if (orientation == gfxTextRunFactory::TEXT_ORIENT_VERTICAL_MIXED) {
orientation = aVertical ?
gfxTextRunFactory::TEXT_ORIENT_VERTICAL_UPRIGHT :
gfxTextRunFactory::TEXT_ORIENT_VERTICAL_SIDEWAYS_RIGHT;
}
if (boundary != ' ' ||
!aTextRun->SetSpaceGlyphIfSimple(this, aRunStart + i, ch,
orientation)) {
// Currently, the only "boundary" characters we recognize are
// space and no-break space, which are both 8-bit, so we force
// that flag (below). If we ever change IsBoundarySpace, we
// may need to revise this.
// Avoid tautological-constant-out-of-range-compare in 8-bit:
DebugOnly<char16_t> boundary16 = boundary;
NS_ASSERTION(boundary16 < 256, "unexpected boundary!");
gfxShapedWord *sw =
GetShapedWord(aContext, &boundary, 1,
gfxShapedWord::HashMix(0, boundary),
aRunScript, aVertical, appUnitsPerDevUnit,
flags | gfxTextRunFactory::TEXT_IS_8BIT, tp);
if (sw) {
aTextRun->CopyGlyphDataFrom(sw, aRunStart + i);
} else {
return false;
}
}
hash = 0;
wordStart = i + 1;
wordIs8Bit = true;
continue;
}
if (i == aRunLength) {
break;
}
NS_ASSERTION(invalid,
"how did we get here except via an invalid char?");
// word was terminated by an invalid char: skip it,
// unless it's a control char that we want to show as a hexbox,
// but record where TAB or NEWLINE occur
if (ch == '\t') {
aTextRun->SetIsTab(aRunStart + i);
} else if (ch == '\n') {
aTextRun->SetIsNewline(aRunStart + i);
} else if (IsInvalidControlChar(ch) &&
!(aTextRun->GetFlags() & gfxTextRunFactory::TEXT_HIDE_CONTROL_CHARACTERS)) {
if (GetFontEntry()->IsUserFont() && HasCharacter(ch)) {
ShapeFragmentWithoutWordCache(aContext, aString + i,
aRunStart + i, 1,
aRunScript, aVertical, aTextRun);
} else {
aTextRun->SetMissingGlyph(aRunStart + i, ch, this);
}
}
hash = 0;
wordStart = i + 1;
wordIs8Bit = true;
}
return true;
}
// Explicit instantiations of SplitAndInitTextRun, to avoid libxul link failure
template bool
gfxFont::SplitAndInitTextRun(gfxContext *aContext,
gfxTextRun *aTextRun,
const uint8_t *aString,
uint32_t aRunStart,
uint32_t aRunLength,
int32_t aRunScript,
bool aVertical);
template bool
gfxFont::SplitAndInitTextRun(gfxContext *aContext,
gfxTextRun *aTextRun,
const char16_t *aString,
uint32_t aRunStart,
uint32_t aRunLength,
int32_t aRunScript,
bool aVertical);
template<>
bool
gfxFont::InitFakeSmallCapsRun(gfxContext *aContext,
gfxTextRun *aTextRun,
const char16_t *aText,
uint32_t aOffset,
uint32_t aLength,
uint8_t aMatchType,
uint16_t aOrientation,
int32_t aScript,
bool aSyntheticLower,
bool aSyntheticUpper)
{
bool ok = true;
RefPtr<gfxFont> smallCapsFont = GetSmallCapsFont();
enum RunCaseAction {
kNoChange,
kUppercaseReduce,
kUppercase
};
RunCaseAction runAction = kNoChange;
uint32_t runStart = 0;
bool vertical =
aOrientation == gfxTextRunFactory::TEXT_ORIENT_VERTICAL_UPRIGHT;
for (uint32_t i = 0; i <= aLength; ++i) {
uint32_t extraCodeUnits = 0; // Will be set to 1 if we need to consume
// a trailing surrogate as well as the
// current code unit.
RunCaseAction chAction = kNoChange;
// Unless we're at the end, figure out what treatment the current
// character will need.
if (i < aLength) {
uint32_t ch = aText[i];
if (NS_IS_HIGH_SURROGATE(ch) && i < aLength - 1 &&
NS_IS_LOW_SURROGATE(aText[i + 1])) {
ch = SURROGATE_TO_UCS4(ch, aText[i + 1]);
extraCodeUnits = 1;
}
// Characters that aren't the start of a cluster are ignored here.
// They get added to whatever lowercase/non-lowercase run we're in.
if (IsClusterExtender(ch)) {
chAction = runAction;
} else {
if (ch != ToUpperCase(ch) || SpecialUpper(ch)) {
// ch is lower case
chAction = (aSyntheticLower ? kUppercaseReduce : kNoChange);
} else if (ch != ToLowerCase(ch)) {
// ch is upper case
chAction = (aSyntheticUpper ? kUppercaseReduce : kNoChange);
if (mStyle.explicitLanguage &&
mStyle.language == nsGkAtoms::el) {
// In Greek, check for characters that will be modified by
// the GreekUpperCase mapping - this catches accented
// capitals where the accent is to be removed (bug 307039).
// These are handled by using the full-size font with the
// uppercasing transform.
mozilla::GreekCasing::State state;
uint32_t ch2 = mozilla::GreekCasing::UpperCase(ch, state);
if (ch != ch2 && !aSyntheticUpper) {
chAction = kUppercase;
}
}
}
}
}
// At the end of the text or when the current character needs different
// casing treatment from the current run, finish the run-in-progress
// and prepare to accumulate a new run.
// Note that we do not look at any source data for offset [i] here,
// as that would be invalid in the case where i==length.
if ((i == aLength || runAction != chAction) && runStart < i) {
uint32_t runLength = i - runStart;
gfxFont* f = this;
switch (runAction) {
case kNoChange:
// just use the current font and the existing string
aTextRun->AddGlyphRun(f, aMatchType, aOffset + runStart, true,
aOrientation);
if (!f->SplitAndInitTextRun(aContext, aTextRun,
aText + runStart,
aOffset + runStart, runLength,
aScript, vertical)) {
ok = false;
}
break;
case kUppercaseReduce:
// use reduced-size font, then fall through to uppercase the text
f = smallCapsFont;
MOZ_FALLTHROUGH;
case kUppercase:
// apply uppercase transform to the string
nsDependentSubstring origString(aText + runStart, runLength);
nsAutoString convertedString;
nsAutoTArray<bool,50> charsToMergeArray;
nsAutoTArray<bool,50> deletedCharsArray;
bool mergeNeeded = nsCaseTransformTextRunFactory::
TransformString(origString,
convertedString,
true,
mStyle.explicitLanguage
? mStyle.language.get() : nullptr,
charsToMergeArray,
deletedCharsArray);
if (mergeNeeded) {
// This is the hard case: the transformation caused chars
// to be inserted or deleted, so we can't shape directly
// into the destination textrun but have to handle the
// mismatch of character positions.
gfxTextRunFactory::Parameters params = {
aContext, nullptr, nullptr, nullptr, 0,
aTextRun->GetAppUnitsPerDevUnit()
};
nsAutoPtr<gfxTextRun> tempRun;
tempRun =
gfxTextRun::Create(&params, convertedString.Length(),
aTextRun->GetFontGroup(), 0);
tempRun->AddGlyphRun(f, aMatchType, 0, true, aOrientation);
if (!f->SplitAndInitTextRun(aContext, tempRun,
convertedString.BeginReading(),
0, convertedString.Length(),
aScript, vertical)) {
ok = false;
} else {
nsAutoPtr<gfxTextRun> mergedRun;
mergedRun =
gfxTextRun::Create(&params, runLength,
aTextRun->GetFontGroup(), 0);
MergeCharactersInTextRun(mergedRun, tempRun,
charsToMergeArray.Elements(),
deletedCharsArray.Elements());
aTextRun->CopyGlyphDataFrom(mergedRun, 0, runLength,
aOffset + runStart);
}
} else {
aTextRun->AddGlyphRun(f, aMatchType, aOffset + runStart,
true, aOrientation);
if (!f->SplitAndInitTextRun(aContext, aTextRun,
convertedString.BeginReading(),
aOffset + runStart, runLength,
aScript, vertical)) {
ok = false;
}
}
break;
}
runStart = i;
}
i += extraCodeUnits;
if (i < aLength) {
runAction = chAction;
}
}
return ok;
}
template<>
bool
gfxFont::InitFakeSmallCapsRun(gfxContext *aContext,
gfxTextRun *aTextRun,
const uint8_t *aText,
uint32_t aOffset,
uint32_t aLength,
uint8_t aMatchType,
uint16_t aOrientation,
int32_t aScript,
bool aSyntheticLower,
bool aSyntheticUpper)
{
NS_ConvertASCIItoUTF16 unicodeString(reinterpret_cast<const char*>(aText),
aLength);
return InitFakeSmallCapsRun(aContext, aTextRun, static_cast<const char16_t*>(unicodeString.get()),
aOffset, aLength, aMatchType, aOrientation,
aScript, aSyntheticLower, aSyntheticUpper);
}
already_AddRefed<gfxFont>
gfxFont::GetSmallCapsFont()
{
gfxFontStyle style(*GetStyle());
style.size *= SMALL_CAPS_SCALE_FACTOR;
style.variantCaps = NS_FONT_VARIANT_CAPS_NORMAL;
gfxFontEntry* fe = GetFontEntry();
bool needsBold = style.weight >= 600 && !fe->IsBold();
return fe->FindOrMakeFont(&style, needsBold, mUnicodeRangeMap);
}
already_AddRefed<gfxFont>
gfxFont::GetSubSuperscriptFont(int32_t aAppUnitsPerDevPixel)
{
gfxFontStyle style(*GetStyle());
style.AdjustForSubSuperscript(aAppUnitsPerDevPixel);
gfxFontEntry* fe = GetFontEntry();
bool needsBold = style.weight >= 600 && !fe->IsBold();
return fe->FindOrMakeFont(&style, needsBold, mUnicodeRangeMap);
}
static void
DestroyRefCairo(void* aData)
{
cairo_t* refCairo = static_cast<cairo_t*>(aData);
MOZ_ASSERT(refCairo);
cairo_destroy(refCairo);
}
/* static */ cairo_t *
gfxFont::RefCairo(DrawTarget* aDT)
{
// DrawTargets that don't use a Cairo backend can be given a 1x1 "reference"
// |cairo_t*|, stored in the DrawTarget's user data, for doing font-related
// operations.
static UserDataKey sRefCairo;
cairo_t* refCairo = nullptr;
if (aDT->GetBackendType() == BackendType::CAIRO) {
refCairo = static_cast<cairo_t*>
(aDT->GetNativeSurface(NativeSurfaceType::CAIRO_CONTEXT));
if (refCairo) {
return refCairo;
}
}
refCairo = static_cast<cairo_t*>(aDT->GetUserData(&sRefCairo));
if (!refCairo) {
refCairo = cairo_create(gfxPlatform::GetPlatform()->ScreenReferenceSurface()->CairoSurface());
aDT->AddUserData(&sRefCairo, refCairo, DestroyRefCairo);
}
return refCairo;
}
gfxGlyphExtents *
gfxFont::GetOrCreateGlyphExtents(int32_t aAppUnitsPerDevUnit) {
uint32_t i, count = mGlyphExtentsArray.Length();
for (i = 0; i < count; ++i) {
if (mGlyphExtentsArray[i]->GetAppUnitsPerDevUnit() == aAppUnitsPerDevUnit)
return mGlyphExtentsArray[i];
}
gfxGlyphExtents *glyphExtents = new gfxGlyphExtents(aAppUnitsPerDevUnit);
if (glyphExtents) {
mGlyphExtentsArray.AppendElement(glyphExtents);
// Initialize the extents of a space glyph, assuming that spaces don't
// render anything!
glyphExtents->SetContainedGlyphWidthAppUnits(GetSpaceGlyph(), 0);
}
return glyphExtents;
}
void
gfxFont::SetupGlyphExtents(DrawTarget* aDrawTarget, uint32_t aGlyphID,
bool aNeedTight, gfxGlyphExtents *aExtents)
{
gfxRect svgBounds;
if (mFontEntry->TryGetSVGData(this) && mFontEntry->HasSVGGlyph(aGlyphID) &&
mFontEntry->GetSVGGlyphExtents(aDrawTarget, aGlyphID, &svgBounds)) {
gfxFloat d2a = aExtents->GetAppUnitsPerDevUnit();
aExtents->SetTightGlyphExtents(aGlyphID,
gfxRect(svgBounds.x * d2a,
svgBounds.y * d2a,
svgBounds.width * d2a,
svgBounds.height * d2a));
return;
}
cairo_glyph_t glyph;
glyph.index = aGlyphID;
glyph.x = 0;
glyph.y = 0;
cairo_text_extents_t extents;
cairo_glyph_extents(gfxFont::RefCairo(aDrawTarget), &glyph, 1, &extents);
const Metrics& fontMetrics = GetMetrics(eHorizontal);
int32_t appUnitsPerDevUnit = aExtents->GetAppUnitsPerDevUnit();
if (!aNeedTight && extents.x_bearing >= 0 &&
extents.y_bearing >= -fontMetrics.maxAscent &&
extents.height + extents.y_bearing <= fontMetrics.maxDescent) {
uint32_t appUnitsWidth =
uint32_t(ceil((extents.x_bearing + extents.width)*appUnitsPerDevUnit));
if (appUnitsWidth < gfxGlyphExtents::INVALID_WIDTH) {
aExtents->SetContainedGlyphWidthAppUnits(aGlyphID, uint16_t(appUnitsWidth));
return;
}
}
#ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
if (!aNeedTight) {
++gGlyphExtentsSetupFallBackToTight;
}
#endif
gfxFloat d2a = appUnitsPerDevUnit;
gfxRect bounds(extents.x_bearing*d2a, extents.y_bearing*d2a,
extents.width*d2a, extents.height*d2a);
aExtents->SetTightGlyphExtents(aGlyphID, bounds);
}
// Try to initialize font metrics by reading sfnt tables directly;
// set mIsValid=TRUE and return TRUE on success.
// Return FALSE if the gfxFontEntry subclass does not
// implement GetFontTable(), or for non-sfnt fonts where tables are
// not available.
// If this returns TRUE without setting the mIsValid flag, then we -did-
// apparently find an sfnt, but it was too broken to be used.
bool
gfxFont::InitMetricsFromSfntTables(Metrics& aMetrics)
{
mIsValid = false; // font is NOT valid in case of early return
const uint32_t kHheaTableTag = TRUETYPE_TAG('h','h','e','a');
const uint32_t kPostTableTag = TRUETYPE_TAG('p','o','s','t');
const uint32_t kOS_2TableTag = TRUETYPE_TAG('O','S','/','2');
uint32_t len;
if (mFUnitsConvFactor < 0.0) {
// If the conversion factor from FUnits is not yet set,
// get the unitsPerEm from the 'head' table via the font entry
uint16_t unitsPerEm = GetFontEntry()->UnitsPerEm();
if (unitsPerEm == gfxFontEntry::kInvalidUPEM) {
return false;
}
mFUnitsConvFactor = GetAdjustedSize() / unitsPerEm;
}
// 'hhea' table is required to get vertical extents
gfxFontEntry::AutoTable hheaTable(mFontEntry, kHheaTableTag);
if (!hheaTable) {
return false; // no 'hhea' table -> not an sfnt
}
const MetricsHeader* hhea =
reinterpret_cast<const MetricsHeader*>
(hb_blob_get_data(hheaTable, &len));
if (len < sizeof(MetricsHeader)) {
return false;
}
#define SET_UNSIGNED(field,src) aMetrics.field = uint16_t(src) * mFUnitsConvFactor
#define SET_SIGNED(field,src) aMetrics.field = int16_t(src) * mFUnitsConvFactor
SET_UNSIGNED(maxAdvance, hhea->advanceWidthMax);
SET_SIGNED(maxAscent, hhea->ascender);
SET_SIGNED(maxDescent, -int16_t(hhea->descender));
SET_SIGNED(externalLeading, hhea->lineGap);
// 'post' table is required for underline metrics
gfxFontEntry::AutoTable postTable(mFontEntry, kPostTableTag);
if (!postTable) {
return true; // no 'post' table -> sfnt is not valid
}
const PostTable *post =
reinterpret_cast<const PostTable*>(hb_blob_get_data(postTable, &len));
if (len < offsetof(PostTable, underlineThickness) + sizeof(uint16_t)) {
return true; // bad post table -> sfnt is not valid
}
SET_SIGNED(underlineOffset, post->underlinePosition);
SET_UNSIGNED(underlineSize, post->underlineThickness);
// 'OS/2' table is optional, if not found we'll estimate xHeight
// and aveCharWidth by measuring glyphs
gfxFontEntry::AutoTable os2Table(mFontEntry, kOS_2TableTag);
if (os2Table) {
const OS2Table *os2 =
reinterpret_cast<const OS2Table*>(hb_blob_get_data(os2Table, &len));
// although sxHeight is a signed field, we consider negative values to
// be erroneous and just ignore them
if (len >= offsetof(OS2Table, sxHeight) + sizeof(int16_t) &&
uint16_t(os2->version) >= 2 && int16_t(os2->sxHeight) > 0) {
// version 2 and later includes the x-height field
SET_SIGNED(xHeight, os2->sxHeight);
}
// this should always be present in any valid OS/2 of any version
if (len >= offsetof(OS2Table, sTypoLineGap) + sizeof(int16_t)) {
SET_SIGNED(aveCharWidth, os2->xAvgCharWidth);
SET_SIGNED(strikeoutSize, os2->yStrikeoutSize);
SET_SIGNED(strikeoutOffset, os2->yStrikeoutPosition);
// for fonts with USE_TYPO_METRICS set in the fsSelection field,
// let the OS/2 sTypo* metrics override those from the hhea table
// (see http://www.microsoft.com/typography/otspec/os2.htm#fss)
const uint16_t kUseTypoMetricsMask = 1 << 7;
if (uint16_t(os2->fsSelection) & kUseTypoMetricsMask) {
SET_SIGNED(maxAscent, os2->sTypoAscender);
SET_SIGNED(maxDescent, - int16_t(os2->sTypoDescender));
SET_SIGNED(externalLeading, os2->sTypoLineGap);
}
}
}
#undef SET_SIGNED
#undef SET_UNSIGNED
mIsValid = true;
return true;
}
static double
RoundToNearestMultiple(double aValue, double aFraction)
{
return floor(aValue/aFraction + 0.5) * aFraction;
}
void gfxFont::CalculateDerivedMetrics(Metrics& aMetrics)
{
aMetrics.maxAscent =
ceil(RoundToNearestMultiple(aMetrics.maxAscent, 1/1024.0));
aMetrics.maxDescent =
ceil(RoundToNearestMultiple(aMetrics.maxDescent, 1/1024.0));
if (aMetrics.xHeight <= 0) {
// only happens if we couldn't find either font metrics
// or a char to measure;
// pick an arbitrary value that's better than zero
aMetrics.xHeight = aMetrics.maxAscent * DEFAULT_XHEIGHT_FACTOR;
}
aMetrics.maxHeight = aMetrics.maxAscent + aMetrics.maxDescent;
if (aMetrics.maxHeight - aMetrics.emHeight > 0.0) {
aMetrics.internalLeading = aMetrics.maxHeight - aMetrics.emHeight;
} else {
aMetrics.internalLeading = 0.0;
}
aMetrics.emAscent = aMetrics.maxAscent * aMetrics.emHeight
/ aMetrics.maxHeight;
aMetrics.emDescent = aMetrics.emHeight - aMetrics.emAscent;
if (GetFontEntry()->IsFixedPitch()) {
// Some Quartz fonts are fixed pitch, but there's some glyph with a bigger
// advance than the average character width... this forces
// those fonts to be recognized like fixed pitch fonts by layout.
aMetrics.maxAdvance = aMetrics.aveCharWidth;
}
if (!aMetrics.strikeoutOffset) {
aMetrics.strikeoutOffset = aMetrics.xHeight * 0.5;
}
if (!aMetrics.strikeoutSize) {
aMetrics.strikeoutSize = aMetrics.underlineSize;
}
}
void
gfxFont::SanitizeMetrics(gfxFont::Metrics *aMetrics, bool aIsBadUnderlineFont)
{
// Even if this font size is zero, this font is created with non-zero size.
// However, for layout and others, we should return the metrics of zero size font.
if (mStyle.size == 0.0 || mStyle.sizeAdjust == 0.0) {
memset(aMetrics, 0, sizeof(gfxFont::Metrics));
return;
}
aMetrics->underlineSize = std::max(1.0, aMetrics->underlineSize);
aMetrics->strikeoutSize = std::max(1.0, aMetrics->strikeoutSize);
aMetrics->underlineOffset = std::min(aMetrics->underlineOffset, -1.0);
if (aMetrics->maxAscent < 1.0) {
// We cannot draw strikeout line and overline in the ascent...
aMetrics->underlineSize = 0;
aMetrics->underlineOffset = 0;
aMetrics->strikeoutSize = 0;
aMetrics->strikeoutOffset = 0;
return;
}
/**
* Some CJK fonts have bad underline offset. Therefore, if this is such font,
* we need to lower the underline offset to bottom of *em* descent.
* However, if this is system font, we should not do this for the rendering compatibility with
* another application's UI on the platform.
* XXX Should not use this hack if the font size is too small?
* Such text cannot be read, this might be used for tight CSS rendering? (E.g., Acid2)
*/
if (!mStyle.systemFont && aIsBadUnderlineFont) {
// First, we need 2 pixels between baseline and underline at least. Because many CJK characters
// put their glyphs on the baseline, so, 1 pixel is too close for CJK characters.
aMetrics->underlineOffset = std::min(aMetrics->underlineOffset, -2.0);
// Next, we put the underline to bottom of below of the descent space.
if (aMetrics->internalLeading + aMetrics->externalLeading > aMetrics->underlineSize) {
aMetrics->underlineOffset = std::min(aMetrics->underlineOffset, -aMetrics->emDescent);
} else {
aMetrics->underlineOffset = std::min(aMetrics->underlineOffset,
aMetrics->underlineSize - aMetrics->emDescent);
}
}
// If underline positioned is too far from the text, descent position is preferred so that underline
// will stay within the boundary.
else if (aMetrics->underlineSize - aMetrics->underlineOffset > aMetrics->maxDescent) {
if (aMetrics->underlineSize > aMetrics->maxDescent)
aMetrics->underlineSize = std::max(aMetrics->maxDescent, 1.0);
// The max underlineOffset is 1px (the min underlineSize is 1px, and min maxDescent is 0px.)
aMetrics->underlineOffset = aMetrics->underlineSize - aMetrics->maxDescent;
}
// If strikeout line is overflowed from the ascent, the line should be resized and moved for
// that being in the ascent space.
// Note that the strikeoutOffset is *middle* of the strikeout line position.
gfxFloat halfOfStrikeoutSize = floor(aMetrics->strikeoutSize / 2.0 + 0.5);
if (halfOfStrikeoutSize + aMetrics->strikeoutOffset > aMetrics->maxAscent) {
if (aMetrics->strikeoutSize > aMetrics->maxAscent) {
aMetrics->strikeoutSize = std::max(aMetrics->maxAscent, 1.0);
halfOfStrikeoutSize = floor(aMetrics->strikeoutSize / 2.0 + 0.5);
}
gfxFloat ascent = floor(aMetrics->maxAscent + 0.5);
aMetrics->strikeoutOffset = std::max(halfOfStrikeoutSize, ascent / 2.0);
}
// If overline is larger than the ascent, the line should be resized.
if (aMetrics->underlineSize > aMetrics->maxAscent) {
aMetrics->underlineSize = aMetrics->maxAscent;
}
}
// Create a Metrics record to be used for vertical layout. This should never
// fail, as we've already decided this is a valid font. We do not have the
// option of marking it invalid (as can happen if we're unable to read
// horizontal metrics), because that could break a font that we're already
// using for horizontal text.
// So we will synthesize *something* usable here even if there aren't any of the
// usual font tables (which can happen in the case of a legacy bitmap or Type1
// font for which the platform-specific backend used platform APIs instead of
// sfnt tables to create the horizontal metrics).
const gfxFont::Metrics*
gfxFont::CreateVerticalMetrics()
{
const uint32_t kHheaTableTag = TRUETYPE_TAG('h','h','e','a');
const uint32_t kVheaTableTag = TRUETYPE_TAG('v','h','e','a');
const uint32_t kPostTableTag = TRUETYPE_TAG('p','o','s','t');
const uint32_t kOS_2TableTag = TRUETYPE_TAG('O','S','/','2');
uint32_t len;
Metrics* metrics = new Metrics;
::memset(metrics, 0, sizeof(Metrics));
// Some basic defaults, in case the font lacks any real metrics tables.
// TODO: consider what rounding (if any) we should apply to these.
metrics->emHeight = GetAdjustedSize();
metrics->emAscent = metrics->emHeight / 2;
metrics->emDescent = metrics->emHeight - metrics->emAscent;
metrics->maxAscent = metrics->emAscent;
metrics->maxDescent = metrics->emDescent;
const float UNINITIALIZED_LEADING = -10000.0f;
metrics->externalLeading = UNINITIALIZED_LEADING;
if (mFUnitsConvFactor < 0.0) {
uint16_t upem = GetFontEntry()->UnitsPerEm();
if (upem != gfxFontEntry::kInvalidUPEM) {
mFUnitsConvFactor = GetAdjustedSize() / upem;
}
}
#define SET_UNSIGNED(field,src) metrics->field = uint16_t(src) * mFUnitsConvFactor
#define SET_SIGNED(field,src) metrics->field = int16_t(src) * mFUnitsConvFactor
gfxFontEntry::AutoTable os2Table(mFontEntry, kOS_2TableTag);
if (os2Table && mFUnitsConvFactor >= 0.0) {
const OS2Table *os2 =
reinterpret_cast<const OS2Table*>(hb_blob_get_data(os2Table, &len));
// These fields should always be present in any valid OS/2 table
if (len >= offsetof(OS2Table, sTypoLineGap) + sizeof(int16_t)) {
SET_SIGNED(strikeoutSize, os2->yStrikeoutSize);
// Use ascent+descent from the horizontal metrics as the default
// advance (aveCharWidth) in vertical mode
gfxFloat ascentDescent = gfxFloat(mFUnitsConvFactor) *
(int16_t(os2->sTypoAscender) - int16_t(os2->sTypoDescender));
metrics->aveCharWidth =
std::max(metrics->emHeight, ascentDescent);
// Use xAvgCharWidth from horizontal metrics as minimum font extent
// for vertical layout, applying half of it to ascent and half to
// descent (to work with a default centered baseline).
gfxFloat halfCharWidth =
int16_t(os2->xAvgCharWidth) * gfxFloat(mFUnitsConvFactor) / 2;
metrics->maxAscent = std::max(metrics->maxAscent, halfCharWidth);
metrics->maxDescent = std::max(metrics->maxDescent, halfCharWidth);
}
}
// If we didn't set aveCharWidth from OS/2, try to read 'hhea' metrics
// and use the line height from its ascent/descent.
if (!metrics->aveCharWidth) {
gfxFontEntry::AutoTable hheaTable(mFontEntry, kHheaTableTag);
if (hheaTable && mFUnitsConvFactor >= 0.0) {
const MetricsHeader* hhea =
reinterpret_cast<const MetricsHeader*>
(hb_blob_get_data(hheaTable, &len));
if (len >= sizeof(MetricsHeader)) {
SET_SIGNED(aveCharWidth, int16_t(hhea->ascender) -
int16_t(hhea->descender));
metrics->maxAscent = metrics->aveCharWidth / 2;
metrics->maxDescent =
metrics->aveCharWidth - metrics->maxAscent;
}
}
}
// Read real vertical metrics if available.
gfxFontEntry::AutoTable vheaTable(mFontEntry, kVheaTableTag);
if (vheaTable && mFUnitsConvFactor >= 0.0) {
const MetricsHeader* vhea =
reinterpret_cast<const MetricsHeader*>
(hb_blob_get_data(vheaTable, &len));
if (len >= sizeof(MetricsHeader)) {
SET_UNSIGNED(maxAdvance, vhea->advanceWidthMax);
// Redistribute space between ascent/descent because we want a
// centered vertical baseline by default.
gfxFloat halfExtent = 0.5 * gfxFloat(mFUnitsConvFactor) *
(int16_t(vhea->ascender) + std::abs(int16_t(vhea->descender)));
// Some bogus fonts have ascent and descent set to zero in 'vhea'.
// In that case we just ignore them and keep our synthetic values
// from above.
if (halfExtent > 0) {
metrics->maxAscent = halfExtent;
metrics->maxDescent = halfExtent;
SET_SIGNED(externalLeading, vhea->lineGap);
}
}
}
// If we didn't set aveCharWidth above, we must be dealing with a non-sfnt
// font of some kind (Type1, bitmap, vector, ...), so fall back to using
// whatever the platform backend figured out for horizontal layout.
// And if we haven't set externalLeading yet, then copy that from the
// horizontal metrics as well, to help consistency of CSS line-height.
if (!metrics->aveCharWidth ||
metrics->externalLeading == UNINITIALIZED_LEADING) {
const Metrics& horizMetrics = GetHorizontalMetrics();
if (!metrics->aveCharWidth) {
metrics->aveCharWidth = horizMetrics.maxAscent + horizMetrics.maxDescent;
}
if (metrics->externalLeading == UNINITIALIZED_LEADING) {
metrics->externalLeading = horizMetrics.externalLeading;
}
}
// Get underline thickness from the 'post' table if available.
gfxFontEntry::AutoTable postTable(mFontEntry, kPostTableTag);
if (postTable) {
const PostTable *post =
reinterpret_cast<const PostTable*>(hb_blob_get_data(postTable,
&len));
if (len >= offsetof(PostTable, underlineThickness) +
sizeof(uint16_t)) {
SET_UNSIGNED(underlineSize, post->underlineThickness);
// Also use for strikeout if we didn't find that in OS/2 above.
if (!metrics->strikeoutSize) {
metrics->strikeoutSize = metrics->underlineSize;
}
}
}
#undef SET_UNSIGNED
#undef SET_SIGNED
// If we didn't read this from a vhea table, it will still be zero.
// In any case, let's make sure it is not less than the value we've
// come up with for aveCharWidth.
metrics->maxAdvance = std::max(metrics->maxAdvance, metrics->aveCharWidth);
// Thickness of underline and strikeout may have been read from tables,
// but in case they were not present, ensure a minimum of 1 pixel.
// We synthesize our own positions, as font metrics don't provide these
// for vertical layout.
metrics->underlineSize = std::max(1.0, metrics->underlineSize);
metrics->underlineOffset = - metrics->maxDescent - metrics->underlineSize;
metrics->strikeoutSize = std::max(1.0, metrics->strikeoutSize);
metrics->strikeoutOffset = - 0.5 * metrics->strikeoutSize;
// Somewhat arbitrary values for now, subject to future refinement...
metrics->spaceWidth = metrics->aveCharWidth;
metrics->zeroOrAveCharWidth = metrics->aveCharWidth;
metrics->maxHeight = metrics->maxAscent + metrics->maxDescent;
metrics->xHeight = metrics->emHeight / 2;
return metrics;
}
gfxFloat
gfxFont::SynthesizeSpaceWidth(uint32_t aCh)
{
// return an appropriate width for various Unicode space characters
// that we "fake" if they're not actually present in the font;
// returns negative value if the char is not a known space.
switch (aCh) {
case 0x2000: // en quad
case 0x2002: return GetAdjustedSize() / 2; // en space
case 0x2001: // em quad
case 0x2003: return GetAdjustedSize(); // em space
case 0x2004: return GetAdjustedSize() / 3; // three-per-em space
case 0x2005: return GetAdjustedSize() / 4; // four-per-em space
case 0x2006: return GetAdjustedSize() / 6; // six-per-em space
case 0x2007: return GetMetrics(eHorizontal).zeroOrAveCharWidth; // figure space
case 0x2008: return GetMetrics(eHorizontal).spaceWidth; // punctuation space
case 0x2009: return GetAdjustedSize() / 5; // thin space
case 0x200a: return GetAdjustedSize() / 10; // hair space
case 0x202f: return GetAdjustedSize() / 5; // narrow no-break space
default: return -1.0;
}
}
void
gfxFont::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const
{
for (uint32_t i = 0; i < mGlyphExtentsArray.Length(); ++i) {
aSizes->mFontInstances +=
mGlyphExtentsArray[i]->SizeOfIncludingThis(aMallocSizeOf);
}
if (mWordCache) {
aSizes->mShapedWords += mWordCache->SizeOfIncludingThis(aMallocSizeOf);
}
}
void
gfxFont::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
FontCacheSizes* aSizes) const
{
aSizes->mFontInstances += aMallocSizeOf(this);
AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
}
void
gfxFont::AddGlyphChangeObserver(GlyphChangeObserver *aObserver)
{
if (!mGlyphChangeObservers) {
mGlyphChangeObservers = new nsTHashtable<nsPtrHashKey<GlyphChangeObserver> >;
}
mGlyphChangeObservers->PutEntry(aObserver);
}
void
gfxFont::RemoveGlyphChangeObserver(GlyphChangeObserver *aObserver)
{
NS_ASSERTION(mGlyphChangeObservers, "No observers registered");
NS_ASSERTION(mGlyphChangeObservers->Contains(aObserver), "Observer not registered");
mGlyphChangeObservers->RemoveEntry(aObserver);
}
#define DEFAULT_PIXEL_FONT_SIZE 16.0f
/*static*/ uint32_t
gfxFontStyle::ParseFontLanguageOverride(const nsString& aLangTag)
{
if (!aLangTag.Length() || aLangTag.Length() > 4) {
return NO_FONT_LANGUAGE_OVERRIDE;
}
uint32_t index, result = 0;
for (index = 0; index < aLangTag.Length(); ++index) {
char16_t ch = aLangTag[index];
if (!nsCRT::IsAscii(ch)) { // valid tags are pure ASCII
return NO_FONT_LANGUAGE_OVERRIDE;
}
result = (result << 8) + ch;
}
while (index++ < 4) {
result = (result << 8) + 0x20;
}
return result;
}
gfxFontStyle::gfxFontStyle() :
language(nsGkAtoms::x_western),
size(DEFAULT_PIXEL_FONT_SIZE), sizeAdjust(-1.0f), baselineOffset(0.0f),
languageOverride(NO_FONT_LANGUAGE_OVERRIDE),
weight(NS_FONT_WEIGHT_NORMAL), stretch(NS_FONT_STRETCH_NORMAL),
systemFont(true), printerFont(false), useGrayscaleAntialiasing(false),
style(NS_FONT_STYLE_NORMAL),
allowSyntheticWeight(true), allowSyntheticStyle(true),
noFallbackVariantFeatures(true),
explicitLanguage(false),
variantCaps(NS_FONT_VARIANT_CAPS_NORMAL),
variantSubSuper(NS_FONT_VARIANT_POSITION_NORMAL)
{
}
gfxFontStyle::gfxFontStyle(uint8_t aStyle, uint16_t aWeight, int16_t aStretch,
gfxFloat aSize,
nsIAtom *aLanguage, bool aExplicitLanguage,
float aSizeAdjust, bool aSystemFont,
bool aPrinterFont,
bool aAllowWeightSynthesis,
bool aAllowStyleSynthesis,
const nsString& aLanguageOverride):
language(aLanguage),
size(aSize), sizeAdjust(aSizeAdjust), baselineOffset(0.0f),
languageOverride(ParseFontLanguageOverride(aLanguageOverride)),
weight(aWeight), stretch(aStretch),
systemFont(aSystemFont), printerFont(aPrinterFont),
useGrayscaleAntialiasing(false),
style(aStyle),
allowSyntheticWeight(aAllowWeightSynthesis),
allowSyntheticStyle(aAllowStyleSynthesis),
noFallbackVariantFeatures(true),
explicitLanguage(aExplicitLanguage),
variantCaps(NS_FONT_VARIANT_CAPS_NORMAL),
variantSubSuper(NS_FONT_VARIANT_POSITION_NORMAL)
{
MOZ_ASSERT(!mozilla::IsNaN(size));
MOZ_ASSERT(!mozilla::IsNaN(sizeAdjust));
if (weight > 900)
weight = 900;
if (weight < 100)
weight = 100;
if (size >= FONT_MAX_SIZE) {
size = FONT_MAX_SIZE;
sizeAdjust = -1.0f;
} else if (size < 0.0) {
NS_WARNING("negative font size");
size = 0.0;
}
if (!language) {
NS_WARNING("null language");
language = nsGkAtoms::x_western;
}
}
gfxFontStyle::gfxFontStyle(const gfxFontStyle& aStyle) :
language(aStyle.language),
featureValueLookup(aStyle.featureValueLookup),
size(aStyle.size), sizeAdjust(aStyle.sizeAdjust),
baselineOffset(aStyle.baselineOffset),
languageOverride(aStyle.languageOverride),
weight(aStyle.weight), stretch(aStyle.stretch),
systemFont(aStyle.systemFont), printerFont(aStyle.printerFont),
useGrayscaleAntialiasing(aStyle.useGrayscaleAntialiasing),
style(aStyle.style),
allowSyntheticWeight(aStyle.allowSyntheticWeight),
allowSyntheticStyle(aStyle.allowSyntheticStyle),
noFallbackVariantFeatures(aStyle.noFallbackVariantFeatures),
explicitLanguage(aStyle.explicitLanguage),
variantCaps(aStyle.variantCaps),
variantSubSuper(aStyle.variantSubSuper)
{
featureSettings.AppendElements(aStyle.featureSettings);
alternateValues.AppendElements(aStyle.alternateValues);
}
int8_t
gfxFontStyle::ComputeWeight() const
{
int8_t baseWeight = (weight + 50) / 100;
if (baseWeight < 0)
baseWeight = 0;
if (baseWeight > 9)
baseWeight = 9;
return baseWeight;
}
void
gfxFontStyle::AdjustForSubSuperscript(int32_t aAppUnitsPerDevPixel)
{
NS_PRECONDITION(variantSubSuper != NS_FONT_VARIANT_POSITION_NORMAL &&
baselineOffset == 0,
"can't adjust this style for sub/superscript");
// calculate the baseline offset (before changing the size)
if (variantSubSuper == NS_FONT_VARIANT_POSITION_SUPER) {
baselineOffset = size * -NS_FONT_SUPERSCRIPT_OFFSET_RATIO;
} else {
baselineOffset = size * NS_FONT_SUBSCRIPT_OFFSET_RATIO;
}
// calculate reduced size, roughly mimicing behavior of font-size: smaller
float cssSize = size * aAppUnitsPerDevPixel / AppUnitsPerCSSPixel();
if (cssSize < NS_FONT_SUB_SUPER_SMALL_SIZE) {
size *= NS_FONT_SUB_SUPER_SIZE_RATIO_SMALL;
} else if (cssSize >= NS_FONT_SUB_SUPER_LARGE_SIZE) {
size *= NS_FONT_SUB_SUPER_SIZE_RATIO_LARGE;
} else {
gfxFloat t = (cssSize - NS_FONT_SUB_SUPER_SMALL_SIZE) /
(NS_FONT_SUB_SUPER_LARGE_SIZE -
NS_FONT_SUB_SUPER_SMALL_SIZE);
size *= (1.0 - t) * NS_FONT_SUB_SUPER_SIZE_RATIO_SMALL +
t * NS_FONT_SUB_SUPER_SIZE_RATIO_LARGE;
}
// clear the variant field
variantSubSuper = NS_FONT_VARIANT_POSITION_NORMAL;
}
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