1 /* 2 * Copyright (c) 2012 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include "config.h" 32 #include "core/platform/graphics/harfbuzz/HarfBuzzFace.h" 33 34 #include "core/platform/graphics/FontPlatformData.h" 35 #include "hb-ot.h" 36 #include "hb.h" 37 38 namespace WebCore { 39 40 const hb_tag_t HarfBuzzFace::vertTag = HB_TAG('v', 'e', 'r', 't'); 41 const hb_tag_t HarfBuzzFace::vrt2Tag = HB_TAG('v', 'r', 't', '2'); 42 43 // Though we have FontCache class, which provides the cache mechanism for 44 // WebKit's font objects, we also need additional caching layer for HarfBuzz 45 // to reduce the memory consumption because hb_face_t should be associated with 46 // underling font data (e.g. CTFontRef, FTFace). 47 48 class FaceCacheEntry : public RefCounted<FaceCacheEntry> { 49 public: 50 static PassRefPtr<FaceCacheEntry> create(hb_face_t* face) 51 { 52 ASSERT(face); 53 return adoptRef(new FaceCacheEntry(face)); 54 } 55 ~FaceCacheEntry() 56 { 57 hb_face_destroy(m_face); 58 } 59 60 hb_face_t* face() { return m_face; } 61 HashMap<uint32_t, uint16_t>* glyphCache() { return &m_glyphCache; } 62 63 private: 64 explicit FaceCacheEntry(hb_face_t* face) 65 : m_face(face) 66 { } 67 68 hb_face_t* m_face; 69 HashMap<uint32_t, uint16_t> m_glyphCache; 70 }; 71 72 typedef HashMap<uint64_t, RefPtr<FaceCacheEntry>, WTF::IntHash<uint64_t>, WTF::UnsignedWithZeroKeyHashTraits<uint64_t> > HarfBuzzFaceCache; 73 74 static HarfBuzzFaceCache* harfBuzzFaceCache() 75 { 76 DEFINE_STATIC_LOCAL(HarfBuzzFaceCache, s_harfBuzzFaceCache, ()); 77 return &s_harfBuzzFaceCache; 78 } 79 80 HarfBuzzFace::HarfBuzzFace(FontPlatformData* platformData, uint64_t uniqueID) 81 : m_platformData(platformData) 82 , m_uniqueID(uniqueID) 83 , m_scriptForVerticalText(HB_SCRIPT_INVALID) 84 { 85 HarfBuzzFaceCache::AddResult result = harfBuzzFaceCache()->add(m_uniqueID, 0); 86 if (result.isNewEntry) 87 result.iterator->value = FaceCacheEntry::create(createFace()); 88 result.iterator->value->ref(); 89 m_face = result.iterator->value->face(); 90 m_glyphCacheForFaceCacheEntry = result.iterator->value->glyphCache(); 91 } 92 93 HarfBuzzFace::~HarfBuzzFace() 94 { 95 HarfBuzzFaceCache::iterator result = harfBuzzFaceCache()->find(m_uniqueID); 96 ASSERT(result != harfBuzzFaceCache()->end()); 97 ASSERT(result.get()->value->refCount() > 1); 98 result.get()->value->deref(); 99 if (result.get()->value->refCount() == 1) 100 harfBuzzFaceCache()->remove(m_uniqueID); 101 } 102 103 static hb_script_t findScriptForVerticalGlyphSubstitution(hb_face_t* face) 104 { 105 static const unsigned maxCount = 32; 106 107 unsigned scriptCount = maxCount; 108 hb_tag_t scriptTags[maxCount]; 109 hb_ot_layout_table_get_script_tags(face, HB_OT_TAG_GSUB, 0, &scriptCount, scriptTags); 110 for (unsigned scriptIndex = 0; scriptIndex < scriptCount; ++scriptIndex) { 111 unsigned languageCount = maxCount; 112 hb_tag_t languageTags[maxCount]; 113 hb_ot_layout_script_get_language_tags(face, HB_OT_TAG_GSUB, scriptIndex, 0, &languageCount, languageTags); 114 for (unsigned languageIndex = 0; languageIndex < languageCount; ++languageIndex) { 115 unsigned featureIndex; 116 if (hb_ot_layout_language_find_feature(face, HB_OT_TAG_GSUB, scriptIndex, languageIndex, HarfBuzzFace::vertTag, &featureIndex) 117 || hb_ot_layout_language_find_feature(face, HB_OT_TAG_GSUB, scriptIndex, languageIndex, HarfBuzzFace::vrt2Tag, &featureIndex)) 118 return hb_ot_tag_to_script(scriptTags[scriptIndex]); 119 } 120 } 121 return HB_SCRIPT_INVALID; 122 } 123 124 void HarfBuzzFace::setScriptForVerticalGlyphSubstitution(hb_buffer_t* buffer) 125 { 126 if (m_scriptForVerticalText == HB_SCRIPT_INVALID) 127 m_scriptForVerticalText = findScriptForVerticalGlyphSubstitution(m_face); 128 hb_buffer_set_script(buffer, m_scriptForVerticalText); 129 } 130 131 } // namespace WebCore 132