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      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 "core/platform/graphics/SimpleFontData.h"
     36 #include "core/platform/graphics/harfbuzz/HarfBuzzShaper.h"
     37 
     38 #include <ApplicationServices/ApplicationServices.h>
     39 #include "hb.h"
     40 
     41 namespace WebCore {
     42 
     43 static hb_position_t floatToHarfBuzzPosition(CGFloat value)
     44 {
     45     return static_cast<hb_position_t>(value * (1 << 16));
     46 }
     47 
     48 static hb_bool_t getGlyph(hb_font_t* hbFont, void* fontData, hb_codepoint_t unicode, hb_codepoint_t variationSelector, hb_codepoint_t* glyph, void* userData)
     49 {
     50     CTFontRef ctFont = reinterpret_cast<FontPlatformData*>(fontData)->ctFont();
     51     UniChar characters[4];
     52     CGGlyph cgGlyphs[4];
     53     size_t length = 0;
     54     U16_APPEND_UNSAFE(characters, length, unicode);
     55     if (!CTFontGetGlyphsForCharacters(ctFont, characters, cgGlyphs, length))
     56         return false;
     57     *glyph = cgGlyphs[0];
     58     return true;
     59 }
     60 
     61 static hb_position_t getGlyphHorizontalAdvance(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, void* userData)
     62 {
     63     CTFontRef ctFont = reinterpret_cast<FontPlatformData*>(fontData)->ctFont();
     64     CGGlyph cgGlyph = glyph;
     65     CGFloat advance = CTFontGetAdvancesForGlyphs(ctFont, kCTFontHorizontalOrientation, &cgGlyph, 0, 1);
     66     return floatToHarfBuzzPosition(advance);
     67 }
     68 
     69 static hb_bool_t getGlyphHorizontalOrigin(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, hb_position_t* x, hb_position_t* y, void* userData)
     70 {
     71     return true;
     72 }
     73 
     74 static hb_bool_t getGlyphExtents(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, hb_glyph_extents_t* extents, void* userData)
     75 {
     76     CTFontRef ctFont = reinterpret_cast<FontPlatformData*>(fontData)->ctFont();
     77     CGRect cgRect;
     78     CGGlyph cgGlyph = glyph;
     79     if (CTFontGetBoundingRectsForGlyphs(ctFont, kCTFontDefaultOrientation, &cgGlyph, &cgRect, 1) == CGRectNull)
     80         return false;
     81     extents->x_bearing = floatToHarfBuzzPosition(cgRect.origin.x);
     82     extents->y_bearing = -floatToHarfBuzzPosition(cgRect.origin.y);
     83     extents->width = floatToHarfBuzzPosition(cgRect.size.width);
     84     extents->height = floatToHarfBuzzPosition(cgRect.size.height);
     85     return true;
     86 }
     87 
     88 static hb_font_funcs_t* harfBuzzCoreTextGetFontFuncs()
     89 {
     90     static hb_font_funcs_t* harfBuzzCoreTextFontFuncs = 0;
     91 
     92     if (!harfBuzzCoreTextFontFuncs) {
     93         harfBuzzCoreTextFontFuncs = hb_font_funcs_create();
     94         hb_font_funcs_set_glyph_func(harfBuzzCoreTextFontFuncs, getGlyph, 0, 0);
     95         hb_font_funcs_set_glyph_h_advance_func(harfBuzzCoreTextFontFuncs, getGlyphHorizontalAdvance, 0, 0);
     96         hb_font_funcs_set_glyph_h_origin_func(harfBuzzCoreTextFontFuncs, getGlyphHorizontalOrigin, 0, 0);
     97         hb_font_funcs_set_glyph_extents_func(harfBuzzCoreTextFontFuncs, getGlyphExtents, 0, 0);
     98         hb_font_funcs_make_immutable(harfBuzzCoreTextFontFuncs);
     99     }
    100     return harfBuzzCoreTextFontFuncs;
    101 }
    102 
    103 static void releaseTableData(void* userData)
    104 {
    105     CFDataRef cfData = reinterpret_cast<CFDataRef>(userData);
    106     CFRelease(cfData);
    107 }
    108 
    109 static hb_blob_t* harfBuzzCoreTextGetTable(hb_face_t* face, hb_tag_t tag, void* userData)
    110 {
    111     CGFontRef cgFont = reinterpret_cast<CGFontRef>(userData);
    112     CFDataRef cfData = CGFontCopyTableForTag(cgFont, tag);
    113     if (!cfData)
    114         return 0;
    115 
    116     const char* data = reinterpret_cast<const char*>(CFDataGetBytePtr(cfData));
    117     const size_t length = CFDataGetLength(cfData);
    118     if (!data || !length)
    119         return 0;
    120     return hb_blob_create(data, length, HB_MEMORY_MODE_READONLY, reinterpret_cast<void*>(const_cast<__CFData*>(cfData)), releaseTableData);
    121 }
    122 
    123 hb_face_t* HarfBuzzFace::createFace()
    124 {
    125     // It seems that CTFontCopyTable of MacOSX10.5 sdk doesn't work for
    126     // OpenType layout tables(GDEF, GSUB, GPOS). Use CGFontCopyTableForTag instead.
    127     hb_face_t* face = hb_face_create_for_tables(harfBuzzCoreTextGetTable, m_platformData->cgFont(), 0);
    128     ASSERT(face);
    129     return face;
    130 }
    131 
    132 hb_font_t* HarfBuzzFace::createFont()
    133 {
    134     hb_font_t* font = hb_font_create(m_face);
    135     hb_font_set_funcs(font, harfBuzzCoreTextGetFontFuncs(), m_platformData, 0);
    136     const float size = m_platformData->m_size;
    137     hb_font_set_ppem(font, size, size);
    138     const int scale = (1 << 16) * static_cast<int>(size);
    139     hb_font_set_scale(font, scale, scale);
    140     hb_font_make_immutable(font);
    141     return font;
    142 }
    143 
    144 GlyphBufferAdvance HarfBuzzShaper::createGlyphBufferAdvance(float width, float height)
    145 {
    146     return CGSizeMake(width, height);
    147 }
    148 
    149 } // namespace WebCore
    150