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32 #include "platform/fonts/harfbuzz/HarfBuzzFace.h"
38 #include "SkTypeface.h"
40 #include "platform/fonts/FontPlatformData.h"
41 #include "platform/fonts/SimpleFontData.h"
42 #include "platform/fonts/GlyphBuffer.h"
43 #include "platform/fonts/harfbuzz/HarfBuzzShaper.h"
46 #include "wtf/HashMap.h"
50 // Our implementation of the callbacks which HarfBuzz requires by using Skia
51 // calls. See the HarfBuzz source for references about what these callbacks do.
53 struct HarfBuzzFontData {
54 HarfBuzzFontData(WTF::HashMap<uint32_t, uint16_t>* glyphCacheForFaceCacheEntry)
55 : m_glyphCacheForFaceCacheEntry(glyphCacheForFaceCacheEntry)
58 WTF::HashMap<uint32_t, uint16_t>* m_glyphCacheForFaceCacheEntry;
61 static hb_position_t SkiaScalarToHarfBuzzPosition(SkScalar value)
63 return SkScalarToFixed(value);
66 static void SkiaGetGlyphWidthAndExtents(SkPaint* paint, hb_codepoint_t codepoint, hb_position_t* width, hb_glyph_extents_t* extents)
68 ASSERT(codepoint <= 0xFFFF);
69 paint->setTextEncoding(SkPaint::kGlyphID_TextEncoding);
73 uint16_t glyph = codepoint;
75 paint->getTextWidths(&glyph, sizeof(glyph), &skWidth, &skBounds);
77 *width = SkiaScalarToHarfBuzzPosition(skWidth);
79 // Invert y-axis because Skia is y-grows-down but we set up HarfBuzz to be y-grows-up.
80 extents->x_bearing = SkiaScalarToHarfBuzzPosition(skBounds.fLeft);
81 extents->y_bearing = SkiaScalarToHarfBuzzPosition(-skBounds.fTop);
82 extents->width = SkiaScalarToHarfBuzzPosition(skBounds.width());
83 extents->height = SkiaScalarToHarfBuzzPosition(-skBounds.height());
87 static hb_bool_t harfBuzzGetGlyph(hb_font_t* hbFont, void* fontData, hb_codepoint_t unicode, hb_codepoint_t variationSelector, hb_codepoint_t* glyph, void* userData)
89 HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(fontData);
91 WTF::HashMap<uint32_t, uint16_t>::AddResult result = hbFontData->m_glyphCacheForFaceCacheEntry->add(unicode, 0);
92 if (result.isNewEntry) {
93 SkPaint* paint = &hbFontData->m_paint;
94 paint->setTextEncoding(SkPaint::kUTF32_TextEncoding);
96 paint->textToGlyphs(&unicode, sizeof(hb_codepoint_t), &glyph16);
97 result.storedValue->value = glyph16;
100 *glyph = result.storedValue->value;
104 static hb_position_t harfBuzzGetGlyphHorizontalAdvance(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, void* userData)
106 HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(fontData);
107 hb_position_t advance = 0;
109 SkiaGetGlyphWidthAndExtents(&hbFontData->m_paint, glyph, &advance, 0);
113 static hb_bool_t harfBuzzGetGlyphHorizontalOrigin(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, hb_position_t* x, hb_position_t* y, void* userData)
115 // Just return true, following the way that HarfBuzz-FreeType
116 // implementation does.
120 static hb_bool_t harfBuzzGetGlyphExtents(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, hb_glyph_extents_t* extents, void* userData)
122 HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(fontData);
124 SkiaGetGlyphWidthAndExtents(&hbFontData->m_paint, glyph, 0, extents);
128 static hb_font_funcs_t* harfBuzzSkiaGetFontFuncs()
130 static hb_font_funcs_t* harfBuzzSkiaFontFuncs = 0;
132 // We don't set callback functions which we can't support.
133 // HarfBuzz will use the fallback implementation if they aren't set.
134 if (!harfBuzzSkiaFontFuncs) {
135 harfBuzzSkiaFontFuncs = hb_font_funcs_create();
136 hb_font_funcs_set_glyph_func(harfBuzzSkiaFontFuncs, harfBuzzGetGlyph, 0, 0);
137 hb_font_funcs_set_glyph_h_advance_func(harfBuzzSkiaFontFuncs, harfBuzzGetGlyphHorizontalAdvance, 0, 0);
138 hb_font_funcs_set_glyph_h_origin_func(harfBuzzSkiaFontFuncs, harfBuzzGetGlyphHorizontalOrigin, 0, 0);
139 hb_font_funcs_set_glyph_extents_func(harfBuzzSkiaFontFuncs, harfBuzzGetGlyphExtents, 0, 0);
140 hb_font_funcs_make_immutable(harfBuzzSkiaFontFuncs);
142 return harfBuzzSkiaFontFuncs;
145 static hb_blob_t* harfBuzzSkiaGetTable(hb_face_t* face, hb_tag_t tag, void* userData)
147 SkTypeface* typeface = reinterpret_cast<SkTypeface*>(userData);
149 const size_t tableSize = typeface->getTableSize(tag);
153 char* buffer = reinterpret_cast<char*>(fastMalloc(tableSize));
156 size_t actualSize = typeface->getTableData(tag, 0, tableSize, buffer);
157 if (tableSize != actualSize) {
162 return hb_blob_create(const_cast<char*>(buffer), tableSize, HB_MEMORY_MODE_WRITABLE, buffer, fastFree);
165 static void destroyHarfBuzzFontData(void* userData)
167 HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(userData);
171 hb_face_t* HarfBuzzFace::createFace()
173 hb_face_t* face = hb_face_create_for_tables(harfBuzzSkiaGetTable, m_platformData->typeface(), 0);
178 hb_font_t* HarfBuzzFace::createFont()
180 HarfBuzzFontData* hbFontData = new HarfBuzzFontData(m_glyphCacheForFaceCacheEntry);
181 m_platformData->setupPaint(&hbFontData->m_paint);
182 hb_font_t* font = hb_font_create(m_face);
183 hb_font_set_funcs(font, harfBuzzSkiaGetFontFuncs(), hbFontData, destroyHarfBuzzFontData);
184 float size = m_platformData->size();
185 int scale = SkiaScalarToHarfBuzzPosition(size);
186 hb_font_set_scale(font, scale, scale);
187 hb_font_make_immutable(font);
191 GlyphBufferAdvance HarfBuzzShaper::createGlyphBufferAdvance(float width, float height)
193 return GlyphBufferAdvance(width, height);
196 } // namespace WebCore