Shape unicode-range: font faces in only one iteration

third_party/WebKit/Source/platform/fonts/FontFallbackIterator.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/fonts/FontFallbackIterator.h"
 
 #include "platform/Logging.h"
 #include "platform/fonts/FontCache.h"
 #include "platform/fonts/FontDescription.h"
 #include "platform/fonts/FontFallbackList.h"
@@ skipping 10 matching lines @@
     return adoptRef(new FontFallbackIterator(
         description, fallbackList, fontFallbackPriority));
 }
 
 FontFallbackIterator::FontFallbackIterator(const FontDescription& description,
     PassRefPtr<FontFallbackList> fallbackList,
     FontFallbackPriority fontFallbackPriority)
     : m_fontDescription(description)
     , m_fontFallbackList(fallbackList)
     , m_currentFontDataIndex(0)
-    , m_segmentedIndex(0)
+    , m_segmentedFaceIndex(0)
     , m_fallbackStage(FontGroupFonts)
     , m_fontFallbackPriority(fontFallbackPriority)
 {
 }
 
 bool FontFallbackIterator::needsHintList() const
 {
     if (m_fallbackStage != FontGroupFonts && m_fallbackStage != SegmentedFace) {
         return false;
     }
 
     const FontData* fontData = m_fontFallbackList->fontDataAt(m_fontDescription, m_currentFontDataIndex);
     return fontData && fontData->isSegmented();
 }
 
 bool FontFallbackIterator::alreadyLoadingRangeForHintChar(UChar32 hintChar)
 {
-    for (auto it = m_loadingCustomFontForRanges.begin(); it != m_loadingCustomFontForRanges.end(); ++it) {
+    for (auto it = m_trackedLoadingRangeSets.begin(); it != m_trackedLoadingRangeSets.end(); ++it) {
         if (it->contains(hintChar))
             return true;
     }
     return false;
 }
 
-bool FontFallbackIterator::rangeContributesForHint(const Vector<UChar32> hintList, const FontDataRange& fontDataRange)
+bool FontFallbackIterator::rangeSetContributesForHint(const Vector<UChar32> hintList, const FontDataForRangeSet& segmentedFace)
 {
     for (auto it = hintList.begin(); it != hintList.end(); ++it) {
-        if (*it >= fontDataRange.from() && *it <= fontDataRange.to()) {
+        if (segmentedFace.contains(*it)) {
             if (!alreadyLoadingRangeForHintChar(*it))
                 return true;
         }
     }
     return false;
 }
 
-void FontFallbackIterator::willUseRange(const AtomicString& family, const FontDataRange& range)
+void FontFallbackIterator::willUseRange(const AtomicString& family, const FontDataForRangeSet& rangeSet)
 {
     FontSelector* selector = m_fontFallbackList->getFontSelector();
     if (!selector)
         return;
 
-    selector->willUseRange(m_fontDescription, family, range);
+    selector->willUseRange(m_fontDescription, family, rangeSet);
 }
 
-const FontDataRange FontFallbackIterator::next(const Vector<UChar32>& hintList)
+const FontDataForRangeSet FontFallbackIterator::next(const Vector<UChar32>& hintList)
 {
     if (m_fallbackStage == OutOfLuck)
-        return FontDataRange();
+        return FontDataForRangeSet();
 
     if (m_fallbackStage == FallbackPriorityFonts) {
         // Only try one fallback priority font,
         // then proceed to regular system fallback.
         m_fallbackStage = SystemFonts;
-        FontDataRange fallbackPriorityFontRange(fallbackPriorityFont(hintList[0]));
+        FontDataForRangeSet fallbackPriorityFontRange(fallbackPriorityFont(hintList[0]));
         if (fallbackPriorityFontRange.hasFontData())
             return fallbackPriorityFontRange;
         return next(hintList);
     }
 
     if (m_fallbackStage == SystemFonts) {
         // We've reached pref + system fallback.
         ASSERT(hintList.size());
         RefPtr<SimpleFontData> systemFont = uniqueSystemFontForHint(hintList[0]);
         if (systemFont)
-            return FontDataRange(systemFont);
+            return FontDataForRangeSet(systemFont);
 
         // If we don't have options from the system fallback anymore or had
         // previously returned them, we only have the last resort font left.
         // TODO: crbug.com/42217 Improve this by doing the last run with a last
         // resort font that has glyphs for everything, for example the Unicode
         // LastResort font, not just Times or Arial.
         FontCache* fontCache = FontCache::fontCache();
         m_fallbackStage = OutOfLuck;
         RefPtr<SimpleFontData> lastResort = fontCache->getLastResortFallbackFont(m_fontDescription).get();
         RELEASE_ASSERT(lastResort);
-        return FontDataRange(lastResort);
+        return FontDataForRangeSet(lastResort);
     }
 
     ASSERT(m_fallbackStage == FontGroupFonts
         || m_fallbackStage == SegmentedFace);
     const FontData* fontData = m_fontFallbackList->fontDataAt(
         m_fontDescription, m_currentFontDataIndex);
 
     if (!fontData) {
         // If there is no fontData coming from the fallback list, it means
         // we are now looking at system fonts, either for prioritized symbol
         // or emoji fonts or by calling system fallback API.
         m_fallbackStage = isNonTextFallbackPriority(m_fontFallbackPriority)
             ? FallbackPriorityFonts
             : SystemFonts;
         return next(hintList);
     }
 
     // Otherwise we've received a fontData from the font-family: set of fonts,
     // and a non-segmented one in this case.
     if (!fontData->isSegmented()) {
         // Skip forward to the next font family for the next call to next().
         m_currentFontDataIndex++;
         if (!fontData->isLoading()) {
             RefPtr<SimpleFontData> nonSegmented = const_cast<SimpleFontData*>(toSimpleFontData(fontData));
-            return FontDataRange(nonSegmented);
+            return FontDataForRangeSet(nonSegmented);
         }
         return next(hintList);
     }
 
     // Iterate over ranges of a segmented font below.
 
     const SegmentedFontData* segmented = toSegmentedFontData(fontData);
     if (m_fallbackStage != SegmentedFace) {
-        m_segmentedIndex = 0;
+        m_segmentedFaceIndex = 0;
         m_fallbackStage = SegmentedFace;
     }
 
-    ASSERT(m_segmentedIndex < segmented->numRanges());
-    FontDataRange currentRange = segmented->rangeAt(m_segmentedIndex);
-    m_segmentedIndex++;
+    ASSERT(m_segmentedFaceIndex < segmented->numFaces());
+    FontDataForRangeSet currentSegmentedFace = segmented->faceAt(m_segmentedFaceIndex);
+    m_segmentedFaceIndex++;
 
-    if (m_segmentedIndex == segmented->numRanges()) {
+    if (m_segmentedFaceIndex == segmented->numFaces()) {
         // Switch from iterating over a segmented face to the next family from
         // the font-family: group of fonts.
         m_fallbackStage = FontGroupFonts;
         m_currentFontDataIndex++;
     }
 
-    if (rangeContributesForHint(hintList, currentRange)) {
-        if (currentRange.fontData()->customFontData())
-            currentRange.fontData()->customFontData()->beginLoadIfNeeded();
-        if (!currentRange.fontData()->isLoading())
-            return currentRange;
-        m_loadingCustomFontForRanges.append(currentRange);
+    if (rangeSetContributesForHint(hintList, currentSegmentedFace)) {
+        if (currentSegmentedFace.fontData()->customFontData())
+            currentSegmentedFace.fontData()->customFontData()->beginLoadIfNeeded();
+        if (!currentSegmentedFace.fontData()->isLoading())
+            return currentSegmentedFace;
+        m_trackedLoadingRangeSets.append(currentSegmentedFace);
     }
 
     return next(hintList);
 }
 
 const PassRefPtr<SimpleFontData> FontFallbackIterator::fallbackPriorityFont(
     UChar32 hint)
 {
     return FontCache::fontCache()->fallbackFontForCharacter(
         m_fontDescription,
@@ skipping 12 matching lines @@
     if (m_visitedSystemFonts.find(hint) != m_visitedSystemFonts.end()) {
         return nullptr;
     }
 
     RefPtr<SimpleFontData> fallbackFont = fontCache->fallbackFontForCharacter(m_fontDescription, hint, m_fontFallbackList->primarySimpleFontData(m_fontDescription));
 
     return m_visitedSystemFonts.add(hint, fallbackFont).storedValue->value;
 }
 
 } // namespace blink