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      1 /*
      2  * Copyright 2009, The Android Open Source Project
      3  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      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 copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  *
     14  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
     15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
     18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     25  */
     26 
     27 #include "config.h"
     28 
     29 #include "EmojiFont.h"
     30 #include "Font.h"
     31 #include "FontCache.h"
     32 #include "SimpleFontData.h"
     33 #include "FloatRect.h"
     34 #include "FontDescription.h"
     35 #include "SkFontHost.h"
     36 #include "SkPaint.h"
     37 #include "SkTypeface.h"
     38 #include "SkTime.h"
     39 
     40 using namespace android;
     41 
     42 namespace WebCore {
     43 
     44 void SimpleFontData::platformInit()
     45 {
     46     SkPaint  paint;
     47     SkPaint::FontMetrics skiaFontMetrics;
     48 
     49     m_platformData.setupPaint(&paint);
     50     paint.getFontMetrics(&skiaFontMetrics);
     51 
     52     float d = SkScalarToFloat(skiaFontMetrics.fDescent);
     53     float s = SkScalarToFloat(skiaFontMetrics.fDescent - skiaFontMetrics.fAscent);
     54     float a = s - d;
     55 
     56     m_fontMetrics.setAscent(a);
     57     m_fontMetrics.setDescent(d);
     58     m_fontMetrics.setXHeight(SkScalarToFloat(-skiaFontMetrics.fAscent) * 0.56f);   // hack I stole from the window's port
     59     float lineGap = SkScalarToFloat(skiaFontMetrics.fLeading);
     60     if (platformData().orientation() == Vertical && lineGap == 0) {
     61         lineGap = skiaFontMetrics.fAvgCharWidth * 0.56f;
     62     }
     63     m_fontMetrics.setLineGap(lineGap);
     64     m_fontMetrics.setLineSpacing(a + d + lineGap);
     65 
     66     if (platformData().orientation() == Vertical && !isTextOrientationFallback()) {
     67         static const uint32_t vheaTag = SkSetFourByteTag('v', 'h', 'e', 'a');
     68         static const uint32_t vorgTag = SkSetFourByteTag('V', 'O', 'R', 'G');
     69         const SkFontID fontID = m_platformData.uniqueID();
     70         size_t vheaSize = SkFontHost::GetTableSize(fontID, vheaTag);
     71         size_t vorgSize = SkFontHost::GetTableSize(fontID, vorgTag);
     72         if ((vheaSize > 0) || (vorgSize > 0))
     73             m_hasVerticalGlyphs = true;
     74     }
     75 }
     76 
     77 void SimpleFontData::platformCharWidthInit()
     78 {
     79     m_avgCharWidth = 0.f;
     80     m_maxCharWidth = 0.f;
     81     initCharWidths();
     82 }
     83 
     84 void SimpleFontData::platformDestroy()
     85 {
     86 }
     87 
     88 SimpleFontData* SimpleFontData::smallCapsFontData(const FontDescription& fontDescription) const
     89 {
     90     if (!m_derivedFontData)
     91         m_derivedFontData = DerivedFontData::create(isCustomFont());
     92     if (!m_derivedFontData->smallCaps)
     93         m_derivedFontData->smallCaps = new SimpleFontData(FontPlatformData(m_platformData, fontDescription.computedSize() * 0.7f));
     94 
     95     return m_derivedFontData->smallCaps.get();
     96 }
     97 
     98 SimpleFontData* SimpleFontData::emphasisMarkFontData(const FontDescription& fontDescription) const
     99 {
    100     if (!m_derivedFontData)
    101         m_derivedFontData = DerivedFontData::create(isCustomFont());
    102     if (!m_derivedFontData->emphasisMark)
    103         m_derivedFontData->emphasisMark = new SimpleFontData(FontPlatformData(m_platformData, fontDescription.computedSize() * 0.5f));
    104 
    105     return m_derivedFontData->emphasisMark.get();
    106 }
    107 
    108 bool SimpleFontData::containsCharacters(const UChar* characters, int length) const
    109 {
    110     SkPaint     paint;
    111 
    112     m_platformData.setupPaint(&paint);
    113     paint.setTextEncoding(SkPaint::kUTF16_TextEncoding);
    114     return paint.containsText(characters, length << 1);
    115 }
    116 
    117 void SimpleFontData::determinePitch()
    118 {
    119     m_treatAsFixedPitch = m_platformData.isFixedPitch();
    120 }
    121 
    122 FloatRect SimpleFontData::platformBoundsForGlyph(Glyph) const
    123 {
    124     return FloatRect();
    125 }
    126 
    127 float SimpleFontData::platformWidthForGlyph(Glyph glyph) const
    128 {
    129     SkASSERT(sizeof(glyph) == 2);   // compile-time assert
    130 
    131     SkPaint  paint;
    132 
    133     m_platformData.setupPaint(&paint);
    134 
    135     float advanceWidth;
    136     if (EmojiFont::IsEmojiGlyph(glyph))
    137         advanceWidth = EmojiFont::GetAdvanceWidth(glyph, paint);
    138     else {
    139         paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
    140         advanceWidth = SkScalarToFloat(paint.measureText(&glyph, 2));
    141     }
    142     return advanceWidth;
    143 }
    144 
    145 
    146 }
    147