C++ GlyphPage::fill方法代码示例

static bool fillGlyphPage(GlyphPage& pageToFill, UChar* buffer, unsigned bufferLength, const Font* font)
{
#if ENABLE(SVG_FONTS)
    if (auto* svgData = font->svgData())
        return svgData->fillSVGGlyphPage(&pageToFill, buffer, bufferLength, font);
#endif
    bool hasGlyphs = pageToFill.fill(buffer, bufferLength, font);
#if ENABLE(OPENTYPE_VERTICAL)
    if (hasGlyphs && font->verticalData())
        font->verticalData()->substituteWithVerticalGlyphs(font, &pageToFill);
#endif
    return hasGlyphs;
}

void GlyphPageTreeNode::initializePage(const FontData* fontData, unsigned pageNumber)
{
    ASSERT(!m_page);

    // This function must not be called for the root of the tree, because that
    // level does not contain any glyphs.
    ASSERT(m_level > 0 && m_parent);

    // The parent's page will be 0 if we are level one or the parent's font data
    // did not contain any glyphs for that page.
    GlyphPage* parentPage = m_parent->page();

    // NULL FontData means we're being asked for the system fallback font.
    if (fontData) {
        if (m_level == 1) {
            // Children of the root hold pure pages. These will cover only one
            // font data's glyphs, and will have glyph index 0 if the font data does not
            // contain the glyph.
            unsigned start = pageNumber * GlyphPage::size;
            UChar buffer[GlyphPage::size * 2 + 2];
            unsigned bufferLength;
            unsigned i;

            // Fill in a buffer with the entire "page" of characters that we want to look up glyphs for.
            if (start < 0x10000) {
                bufferLength = GlyphPage::size;
                for (i = 0; i < GlyphPage::size; i++)
                    buffer[i] = start + i;

                if (start == 0) {
                    // Control characters must not render at all.
                    for (i = 0; i < 0x20; ++i)
                        buffer[i] = zeroWidthSpace;
                    for (i = 0x7F; i < 0xA0; i++)
                        buffer[i] = zeroWidthSpace;

                    // \n, \t, and nonbreaking space must render as a space.
                    buffer[(int)'\n'] = ' ';
                    buffer[(int)'\t'] = ' ';
                    buffer[noBreakSpace] = ' ';
                } else if (start == (leftToRightMark & ~(GlyphPage::size - 1))) {
                    // LRM, RLM, LRE, RLE and PDF must not render at all.
                    buffer[leftToRightMark - start] = zeroWidthSpace;
                    buffer[rightToLeftMark - start] = zeroWidthSpace;
                    buffer[leftToRightEmbed - start] = zeroWidthSpace;
                    buffer[rightToLeftEmbed - start] = zeroWidthSpace;
                    buffer[leftToRightOverride - start] = zeroWidthSpace;
                    buffer[rightToLeftOverride - start] = zeroWidthSpace;
                    buffer[popDirectionalFormatting - start] = zeroWidthSpace;
                } else if (start == (objectReplacementCharacter & ~(GlyphPage::size - 1))) {
                    // Object replacement character must not render at all.
                    buffer[objectReplacementCharacter - start] = zeroWidthSpace;
                }
            } else {
                bufferLength = GlyphPage::size * 2;
                for (i = 0; i < GlyphPage::size; i++) {
                    int c = i + start;
                    buffer[i * 2] = U16_LEAD(c);
                    buffer[i * 2 + 1] = U16_TRAIL(c);
                }
            }
            
            m_page = GlyphPage::create(this);

            // Now that we have a buffer full of characters, we want to get back an array
            // of glyph indices.  This part involves calling into the platform-specific 
            // routine of our glyph map for actually filling in the page with the glyphs.
            // Success is not guaranteed. For example, Times fails to fill page 260, giving glyph data
            // for only 128 out of 256 characters.
            bool haveGlyphs;
            if (fontData->isSegmented()) {
                haveGlyphs = false;

                const SegmentedFontData* segmentedFontData = static_cast<const SegmentedFontData*>(fontData);
                unsigned numRanges = segmentedFontData->numRanges();
                bool zeroFilled = false;
                RefPtr<GlyphPage> scratchPage;
                GlyphPage* pageToFill = m_page.get();
                for (unsigned i = 0; i < numRanges; i++) {
                    const FontDataRange& range = segmentedFontData->rangeAt(i);
                    int from = max(0, range.from() - static_cast<int>(start));
                    int to = 1 + min(range.to() - static_cast<int>(start), static_cast<int>(GlyphPage::size) - 1);
                    if (from < static_cast<int>(GlyphPage::size) && to > 0) {
                        if (haveGlyphs && !scratchPage) {
                            scratchPage = GlyphPage::create(this);
                            pageToFill = scratchPage.get();
                        }

                        if (!zeroFilled) {
                            if (from > 0 || to < static_cast<int>(GlyphPage::size)) {
                                for (unsigned i = 0; i < GlyphPage::size; i++)
                                    pageToFill->setGlyphDataForIndex(i, 0, 0);
                            }
                            zeroFilled = true;
                        }
                        haveGlyphs |= pageToFill->fill(from, to - from, buffer + from * (start < 0x10000 ? 1 : 2), (to - from) * (start < 0x10000 ? 1 : 2), range.fontData());
                        if (scratchPage) {
                            for (int j = from; j < to; j++) {
                                if (!m_page->m_glyphs[j].glyph && pageToFill->m_glyphs[j].glyph)
                                    m_page->m_glyphs[j] = pageToFill->m_glyphs[j];
//.........这里部分代码省略.........