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      1 /*
      2  * Copyright (c) 2006, 2007, 2008, 2009, 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,
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     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 "UniscribeHelperTextRun.h"
     33 
     34 #include "Font.h"
     35 #include "PlatformBridge.h"
     36 #include "SimpleFontData.h"
     37 #include "TextRun.h"
     38 
     39 namespace WebCore {
     40 
     41 UniscribeHelperTextRun::UniscribeHelperTextRun(const TextRun& run,
     42                                                const Font& font)
     43     : UniscribeHelper(run.characters(), run.length(), run.rtl(),
     44                       font.primaryFont()->platformData().hfont(),
     45                       font.primaryFont()->platformData().scriptCache(),
     46                       font.primaryFont()->platformData().scriptFontProperties(),
     47                       font.primaryFont()->spaceGlyph())
     48     , m_font(&font)
     49     , m_fontIndex(0)
     50 {
     51     setDirectionalOverride(run.directionalOverride());
     52     setLetterSpacing(font.letterSpacing());
     53     setSpaceWidth(font.spaceWidth());
     54     setWordSpacing(font.wordSpacing());
     55     setAscent(font.fontMetrics().ascent());
     56 
     57     init();
     58 
     59     // Expansion is the amount to add to make justification happen. This
     60     // should be done after Init() so all the runs are already measured.
     61     if (run.expansion() > 0)
     62         justify(run.expansion());
     63 }
     64 
     65 UniscribeHelperTextRun::UniscribeHelperTextRun(
     66     const wchar_t* input,
     67     int inputLength,
     68     bool isRtl,
     69     HFONT hfont,
     70     SCRIPT_CACHE* scriptCache,
     71     SCRIPT_FONTPROPERTIES* fontProperties)
     72     : UniscribeHelper(input, inputLength, isRtl, hfont,
     73                       scriptCache, fontProperties, 0)
     74     , m_font(0)
     75     , m_fontIndex(-1)
     76 {
     77 }
     78 
     79 void UniscribeHelperTextRun::tryToPreloadFont(HFONT font)
     80 {
     81     // Ask the browser to get the font metrics for this font.
     82     // That will preload the font and it should now be accessible
     83     // from the renderer.
     84     PlatformBridge::ensureFontLoaded(font);
     85 }
     86 
     87 bool UniscribeHelperTextRun::nextWinFontData(
     88     HFONT* hfont,
     89     SCRIPT_CACHE** scriptCache,
     90     SCRIPT_FONTPROPERTIES** fontProperties,
     91     int* ascent)
     92 {
     93     // This check is necessary because NextWinFontData can be called again
     94     // after we already ran out of fonts. fontDataAt behaves in a strange
     95     // manner when the difference between param passed and # of fonts stored in
     96     // WebKit::Font is larger than one. We can avoid this check by setting
     97     // font_index_ to # of elements in hfonts_ when we run out of font. In that
     98     // case, we'd have to go through a couple of more checks before returning
     99     // false.
    100     if (m_fontIndex == -1 || !m_font)
    101         return false;
    102 
    103     // If the font data for a fallback font requested is not yet retrieved, add
    104     // them to our vectors. Note that '>' rather than '>=' is used to test that
    105     // condition. primaryFont is not stored in hfonts_, and friends so that
    106     // indices for fontDataAt and our vectors for font data are 1 off from each
    107     // other.  That is, when fully populated, hfonts_ and friends have one font
    108     // fewer than what's contained in font_.
    109     if (static_cast<size_t>(++m_fontIndex) > m_hfonts.size()) {
    110         const FontData *fontData = m_font->fontDataAt(m_fontIndex);
    111         if (!fontData) {
    112             // Ran out of fonts.
    113             m_fontIndex = -1;
    114             return false;
    115         }
    116 
    117         // FIXME: this won't work for SegmentedFontData
    118         // http://crbug.com/6425
    119         const SimpleFontData* simpleFontData =
    120             fontData->fontDataForCharacter(' ');
    121 
    122         m_hfonts.append(simpleFontData->platformData().hfont());
    123         m_scriptCaches.append(simpleFontData->platformData().scriptCache());
    124         m_fontProperties.append(simpleFontData->platformData().scriptFontProperties());
    125         m_ascents.append(simpleFontData->fontMetrics().ascent());
    126     }
    127 
    128     *hfont = m_hfonts[m_fontIndex - 1];
    129     *scriptCache = m_scriptCaches[m_fontIndex - 1];
    130     *fontProperties = m_fontProperties[m_fontIndex - 1];
    131     *ascent = m_ascents[m_fontIndex - 1];
    132     return true;
    133 }
    134 
    135 void UniscribeHelperTextRun::resetFontIndex()
    136 {
    137     m_fontIndex = 0;
    138 }
    139 
    140 }  // namespace WebCore
    141