void Font::platformGlyphInit() { auto* glyphPageZero = glyphPage(0); if (!glyphPageZero) { determinePitch(); return; } // Ask for the glyph for 0 to avoid paging in ZERO WIDTH SPACE. Control characters, including 0, // are mapped to the ZERO WIDTH SPACE glyph. m_zeroWidthSpaceGlyph = glyphPageZero->glyphDataForCharacter(0).glyph; // Nasty hack to determine if we should round or ceil space widths. // If the font is monospace or fake monospace we ceil to ensure that // every character and the space are the same width. Otherwise we round. m_spaceGlyph = glyphPageZero->glyphDataForCharacter(' ').glyph; float width = widthForGlyph(m_spaceGlyph); m_spaceWidth = width; m_zeroGlyph = glyphPageZero->glyphDataForCharacter('0').glyph; m_fontMetrics.setZeroWidth(widthForGlyph(m_zeroGlyph)); determinePitch(); m_adjustedSpaceWidth = m_treatAsFixedPitch ? ceilf(width) : roundf(width); // Force the glyph for ZERO WIDTH SPACE to have zero width, unless it is shared with SPACE. // Helvetica is an example of a non-zero width ZERO WIDTH SPACE glyph. // See <http://bugs.webkit.org/show_bug.cgi?id=13178> and Font::isZeroWidthSpaceGlyph() if (m_zeroWidthSpaceGlyph == m_spaceGlyph) m_zeroWidthSpaceGlyph = 0; }
void SimpleFontData::platformInit() { FS_FIXED ascender = 0; FS_FIXED descender = 0; FS_FIXED leading = 0; FsAscDescLeadSource source; FS_LONG result; if (m_platformData.size() > 0) { // FIXME: hack! FS_get_ascender_descender_leading() returns ERR_NO_CURRENT_SFNT when size is 0, even though we called FS_set_scale and m_platformData.font()->cur_sfnt is not 0 result = FS_get_ascender_descender_leading(m_platformData.font(), &ascender, &descender, &leading, &source); ASSERT_UNUSED(result, result == SUCCESS); } m_fontMetrics.setAscent(FS_ROUND(ascender)); m_fontMetrics.setDescent(FS_ROUND(descender)); m_fontMetrics.setLineGap(iTypeFixedToFloat(leading)); m_fontMetrics.setLineSpacing(lroundf(m_fontMetrics.ascent()) + lroundf(m_fontMetrics.descent()) + lroundf(m_fontMetrics.lineGap())); FONT_METRICS metrics; result = FS_font_metrics(m_platformData.font(), &metrics); ASSERT_UNUSED(result, result == SUCCESS); // m_fontMetrics.setUnitsPerEm(FS_get_design_units(m_platformData().font())); m_fontMetrics.setUnitsPerEm(metrics.unitsPerEm); FS_USHORT xRange = metrics.font_bbox.xMax - metrics.font_bbox.xMin; m_maxCharWidth = roundf((xRange * roundf(m_platformData.size())) / metrics.unitsPerEm); TTF_OS2 os2; if (FS_get_table_structure(m_platformData.font(), TAG_OS2, &os2) == SUCCESS && os2.sxHeight && os2.xAvgCharWidth) { FS_USHORT yppem = m_platformData.font()->lpm; m_fontMetrics.setXHeight(static_cast<float>(os2.sxHeight) * yppem / metrics.unitsPerEm); m_avgCharWidth = static_cast<float>(os2.xAvgCharWidth) * yppem / metrics.unitsPerEm; } else { // HACK m_fontMetrics.setXHeight(m_fontMetrics.ascent() * 0.56); m_fontMetrics.setHasXHeight(false); m_avgCharWidth = m_fontMetrics.xHeight(); GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (glyphPageZero) { static const UChar32 xChar = 'x'; const Glyph xGlyph = glyphPageZero->glyphDataForCharacter(xChar).glyph; if (xGlyph) { // In widthForGlyph(), xGlyph will be compared with // m_zeroWidthSpaceGlyph, which isn't initialized yet here. // Initialize it with zero to make sure widthForGlyph() returns // the right width. m_zeroWidthSpaceGlyph = 0; m_avgCharWidth = widthForGlyph(xGlyph); } } } if (m_platformData.orientation() == Vertical && !isTextOrientationFallback()) m_hasVerticalGlyphs = FS_get_table(m_platformData.font(), openTypeTag('v', 'h', 'e', 'a'), TBL_QUERY, 0) || FS_get_table(m_platformData.font(), openTypeTag('V', 'O', 'R', 'G'), TBL_QUERY, 0); }
void SimpleFontData::platformGlyphInit() { GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (!glyphPageZero) { LOG_ERROR("Failed to get glyph page zero."); m_spaceGlyph = 0; m_spaceWidth = 0; m_zeroGlyph = 0; m_adjustedSpaceWidth = 0; determinePitch(); m_zeroWidthSpaceGlyph = 0; m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; return; } m_zeroWidthSpaceGlyph = glyphPageZero->glyphDataForCharacter(0).glyph; // Nasty hack to determine if we should round or ceil space widths. // If the font is monospace or fake monospace we ceil to ensure that // every character and the space are the same width. Otherwise we round. m_spaceGlyph = glyphPageZero->glyphDataForCharacter(' ').glyph; float width = widthForGlyph(m_spaceGlyph); m_spaceWidth = width; m_zeroGlyph = glyphPageZero->glyphDataForCharacter('0').glyph; m_fontMetrics.setZeroWidth(widthForGlyph(m_zeroGlyph)); determinePitch(); m_adjustedSpaceWidth = m_treatAsFixedPitch ? ceilf(width) : roundf(width); // Force the glyph for ZERO WIDTH SPACE to have zero width, unless it is shared with SPACE. // Helvetica is an example of a non-zero width ZERO WIDTH SPACE glyph. // See <http://bugs.webkit.org/show_bug.cgi?id=13178> // Ask for the glyph for 0 to avoid paging in ZERO WIDTH SPACE. Control characters, including 0, // are mapped to the ZERO WIDTH SPACE glyph. if (m_zeroWidthSpaceGlyph == m_spaceGlyph) { m_zeroWidthSpaceGlyph = 0; LOG_ERROR("Font maps SPACE and ZERO WIDTH SPACE to the same glyph. Glyph width will not be overridden."); } m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; }
void SimpleFontData::platformGlyphInit() { SkTypeface* typeface = platformData().typeface(); if (!typeface->countGlyphs()) { m_spaceGlyph = 0; m_spaceWidth = 0; m_zeroGlyph = 0; m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; return; } // Nasty hack to determine if we should round or ceil space widths. // If the font is monospace or fake monospace we ceil to ensure that // every character and the space are the same width. Otherwise we round. m_spaceGlyph = glyphForCharacter(' '); float width = widthForGlyph(m_spaceGlyph); m_spaceWidth = width; m_zeroGlyph = glyphForCharacter('0'); m_fontMetrics.setZeroWidth(widthForGlyph(m_zeroGlyph)); m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; }
void SimpleFontData::platformInit() { SkPaint paint; SkPaint::FontMetrics metrics; m_font.setupPaint(&paint); paint.getFontMetrics(&metrics); // Beware those who step here: This code is designed to match Win32 font // metrics *exactly*. if (metrics.fVDMXMetricsValid) { m_ascent = metrics.fVDMXAscent; m_descent = metrics.fVDMXDescent; } else { m_ascent = SkScalarRound(-metrics.fAscent); m_descent = SkScalarRound(metrics.fHeight) - m_ascent; } if (metrics.fXHeight) m_xHeight = metrics.fXHeight; else { // hack taken from the Windows port m_xHeight = static_cast<float>(m_ascent) * 0.56; } m_lineGap = SkScalarRound(metrics.fLeading); m_lineSpacing = m_ascent + m_descent + m_lineGap; // In WebKit/WebCore/platform/graphics/SimpleFontData.cpp, m_spaceWidth is // calculated for us, but we need to calculate m_maxCharWidth and // m_avgCharWidth in order for text entry widgets to be sized correctly. m_maxCharWidth = SkScalarRound(metrics.fXRange * SkScalarRound(m_font.size())); if (metrics.fAvgCharWidth) m_avgCharWidth = SkScalarRound(metrics.fAvgCharWidth); else { m_avgCharWidth = m_xHeight; GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (glyphPageZero) { static const UChar32 x_char = 'x'; const Glyph xGlyph = glyphPageZero->glyphDataForCharacter(x_char).glyph; if (xGlyph) m_avgCharWidth = widthForGlyph(xGlyph); } } }
FontData::FontData(const FontPlatformData& f) : m_font(f) , m_treatAsFixedPitch(false) , m_smallCapsFontData(0) { platformInit(); // Nasty hack to determine if we should round or ceil space widths. // If the font is monospace or fake monospace we ceil to ensure that // every character and the space are the same width. Otherwise we round. m_spaceGlyph = GlyphPageTreeNode::getRootChild(this, 0)->page()->glyphDataForCharacter(' ').glyph; float width = widthForGlyph(m_spaceGlyph); m_spaceWidth = width; determinePitch(); m_adjustedSpaceWidth = m_treatAsFixedPitch ? ceilf(width) : roundf(width); m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; }
// Estimates of avgCharWidth and maxCharWidth for platforms that don't support accessing these values from the font. void Font::initCharWidths() { auto* glyphPageZero = glyphPage(0); // Treat the width of a '0' as the avgCharWidth. if (m_avgCharWidth <= 0.f && glyphPageZero) { static const UChar32 digitZeroChar = '0'; Glyph digitZeroGlyph = glyphPageZero->glyphDataForCharacter(digitZeroChar).glyph; if (digitZeroGlyph) m_avgCharWidth = widthForGlyph(digitZeroGlyph); } // If we can't retrieve the width of a '0', fall back to the x height. if (m_avgCharWidth <= 0.f) m_avgCharWidth = m_fontMetrics.xHeight(); if (m_maxCharWidth <= 0.f) m_maxCharWidth = std::max(m_avgCharWidth, m_fontMetrics.floatAscent()); }
// Estimates of avgCharWidth and maxCharWidth for platforms that don't support accessing these values from the font. void SimpleFontData::initCharWidths() { GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); // Treat the width of a '0' as the avgCharWidth. if (m_avgCharWidth <= 0.f && glyphPageZero) { static const UChar32 digitZeroChar = '0'; Glyph digitZeroGlyph = glyphPageZero->glyphDataForCharacter(digitZeroChar).glyph; if (digitZeroGlyph) m_avgCharWidth = widthForGlyph(digitZeroGlyph); } // If we can't retrieve the width of a '0', fall back to the x height. if (m_avgCharWidth <= 0.f) m_avgCharWidth = m_fontMetrics.xHeight(); if (m_maxCharWidth <= 0.f) m_maxCharWidth = max(m_avgCharWidth, m_fontMetrics.floatAscent()); }
void SimpleFontData::platformInit(bool subpixelAscentDescent) { if (!m_platformData.size()) { m_fontMetrics.reset(); m_avgCharWidth = 0; m_maxCharWidth = 0; return; } SkPaint::FontMetrics metrics; m_platformData.setupPaint(&m_paint); m_paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding); m_paint.getFontMetrics(&metrics); SkTypeface* face = m_paint.getTypeface(); ASSERT(face); int vdmxAscent = 0, vdmxDescent = 0; bool isVDMXValid = false; #if OS(LINUX) || OS(ANDROID) // Manually digging up VDMX metrics is only applicable when bytecode hinting // using FreeType. With DirectWrite or CoreText, no bytecode hinting is ever // done. This code should be pushed into FreeType (hinted font metrics). static const uint32_t vdmxTag = SkSetFourByteTag('V', 'D', 'M', 'X'); int pixelSize = m_platformData.size() + 0.5; if (!m_paint.isAutohinted() && (m_paint.getHinting() == SkPaint::kFull_Hinting || m_paint.getHinting() == SkPaint::kNormal_Hinting)) { size_t vdmxSize = face->getTableSize(vdmxTag); if (vdmxSize && vdmxSize < maxVDMXTableSize) { uint8_t* vdmxTable = (uint8_t*)WTF::Partitions::fastMalloc( vdmxSize, WTF_HEAP_PROFILER_TYPE_NAME(SimpleFontData)); if (vdmxTable && face->getTableData(vdmxTag, 0, vdmxSize, vdmxTable) == vdmxSize && parseVDMX(&vdmxAscent, &vdmxDescent, vdmxTable, vdmxSize, pixelSize)) isVDMXValid = true; WTF::Partitions::fastFree(vdmxTable); } } #endif float ascent; float descent; // Beware those who step here: This code is designed to match Win32 font // metrics *exactly* except: // - the adjustment of ascent/descent on Linux/Android // - metrics.fAscent and .fDesscent are not rounded to int for tiny fonts if (isVDMXValid) { ascent = vdmxAscent; descent = -vdmxDescent; } else { // For tiny fonts, the rounding of fAscent and fDescent results in equal // baseline for different types of text baselines (crbug.com/338908). // Please see CanvasRenderingContext2D::getFontBaseline for the heuristic. if (subpixelAscentDescent && (-metrics.fAscent < 3 || -metrics.fAscent + metrics.fDescent < 2)) { ascent = -metrics.fAscent; descent = metrics.fDescent; } else { ascent = SkScalarRoundToScalar(-metrics.fAscent); descent = SkScalarRoundToScalar(metrics.fDescent); } #if OS(LINUX) || OS(ANDROID) // When subpixel positioning is enabled, if the descent is rounded down, the // descent part of the glyph may be truncated when displayed in a 'overflow: // hidden' container. To avoid that, borrow 1 unit from the ascent when // possible. // FIXME: This can be removed if sub-pixel ascent/descent is supported. if (platformData().getFontRenderStyle().useSubpixelPositioning && descent < SkScalarToFloat(metrics.fDescent) && ascent >= 1) { ++descent; --ascent; } #endif } #if OS(MACOSX) // We are preserving this ascent hack to match Safari's ascent adjustment // in their SimpleFontDataMac.mm, for details see crbug.com/445830. // We need to adjust Times, Helvetica, and Courier to closely match the // vertical metrics of their Microsoft counterparts that are the de facto // web standard. The AppKit adjustment of 20% is too big and is // incorrectly added to line spacing, so we use a 15% adjustment instead // and add it to the ascent. DEFINE_STATIC_LOCAL(AtomicString, timesName, ("Times")); DEFINE_STATIC_LOCAL(AtomicString, helveticaName, ("Helvetica")); DEFINE_STATIC_LOCAL(AtomicString, courierName, ("Courier")); String familyName = m_platformData.fontFamilyName(); if (familyName == timesName || familyName == helveticaName || familyName == courierName) ascent += floorf(((ascent + descent) * 0.15f) + 0.5f); #endif m_fontMetrics.setAscent(ascent); m_fontMetrics.setDescent(descent); float xHeight; if (metrics.fXHeight) { xHeight = metrics.fXHeight; #if OS(MACOSX) // Mac OS CTFontGetXHeight reports the bounding box height of x, // including parts extending below the baseline and apparently no x-height // value from the OS/2 table. However, the CSS ex unit // expects only parts above the baseline, hence measuring the glyph: // http://www.w3.org/TR/css3-values/#ex-unit const Glyph xGlyph = glyphForCharacter('x'); if (xGlyph) { FloatRect glyphBounds(boundsForGlyph(xGlyph)); // SkGlyph bounds, y down, based on rendering at (0,0). xHeight = -glyphBounds.y(); } #endif m_fontMetrics.setXHeight(xHeight); } else { xHeight = ascent * 0.56; // Best guess from Windows font metrics. m_fontMetrics.setXHeight(xHeight); m_fontMetrics.setHasXHeight(false); } float lineGap = SkScalarToFloat(metrics.fLeading); m_fontMetrics.setLineGap(lineGap); m_fontMetrics.setLineSpacing(lroundf(ascent) + lroundf(descent) + lroundf(lineGap)); if (platformData().isVerticalAnyUpright() && !isTextOrientationFallback()) { static const uint32_t vheaTag = SkSetFourByteTag('v', 'h', 'e', 'a'); static const uint32_t vorgTag = SkSetFourByteTag('V', 'O', 'R', 'G'); size_t vheaSize = face->getTableSize(vheaTag); size_t vorgSize = face->getTableSize(vorgTag); if ((vheaSize > 0) || (vorgSize > 0)) m_hasVerticalGlyphs = true; } // In WebKit/WebCore/platform/graphics/SimpleFontData.cpp, m_spaceWidth is // calculated for us, but we need to calculate m_maxCharWidth and // m_avgCharWidth in order for text entry widgets to be sized correctly. #if OS(WIN) m_maxCharWidth = SkScalarRoundToInt(metrics.fMaxCharWidth); // Older version of the DirectWrite API doesn't implement support for max // char width. Fall back on a multiple of the ascent. This is entirely // arbitrary but comes pretty close to the expected value in most cases. if (m_maxCharWidth < 1) m_maxCharWidth = ascent * 2; #elif OS(MACOSX) // FIXME: The current avg/max character width calculation is not ideal, // it should check either the OS2 table or, better yet, query FontMetrics. // Sadly FontMetrics provides incorrect data on Mac at the moment. // https://crbug.com/420901 m_maxCharWidth = std::max(m_avgCharWidth, m_fontMetrics.floatAscent()); #else // Better would be to rely on either fMaxCharWidth or fAveCharWidth. // skbug.com/3087 m_maxCharWidth = SkScalarRoundToInt(metrics.fXMax - metrics.fXMin); #endif #if !OS(MACOSX) if (metrics.fAvgCharWidth) { m_avgCharWidth = SkScalarRoundToInt(metrics.fAvgCharWidth); } else { #endif m_avgCharWidth = xHeight; const Glyph xGlyph = glyphForCharacter('x'); if (xGlyph) { m_avgCharWidth = widthForGlyph(xGlyph); } #if !OS(MACOSX) } #endif if (int unitsPerEm = face->getUnitsPerEm()) m_fontMetrics.setUnitsPerEm(unitsPerEm); }
void SimpleFontData::platformInit() { if (!m_platformData.size()) { m_fontMetrics.reset(); m_avgCharWidth = 0; m_maxCharWidth = 0; return; } SkPaint paint; SkPaint::FontMetrics metrics; m_platformData.setupPaint(&paint); paint.getFontMetrics(&metrics); const SkFontID fontID = m_platformData.uniqueID(); static const uint32_t vdmxTag = SkSetFourByteTag('V', 'D', 'M', 'X'); int pixelSize = m_platformData.size() + 0.5; int vdmxAscent, vdmxDescent; bool isVDMXValid = false; size_t vdmxSize = SkFontHost::GetTableSize(fontID, vdmxTag); if (vdmxSize && vdmxSize < maxVDMXTableSize) { uint8_t* vdmxTable = (uint8_t*) fastMalloc(vdmxSize); if (vdmxTable && SkFontHost::GetTableData(fontID, vdmxTag, 0, vdmxSize, vdmxTable) == vdmxSize && parseVDMX(&vdmxAscent, &vdmxDescent, vdmxTable, vdmxSize, pixelSize)) isVDMXValid = true; fastFree(vdmxTable); } float ascent; float descent; // Beware those who step here: This code is designed to match Win32 font // metrics *exactly*. if (isVDMXValid) { ascent = vdmxAscent; descent = -vdmxDescent; } else { SkScalar height = -metrics.fAscent + metrics.fDescent + metrics.fLeading; ascent = SkScalarRound(-metrics.fAscent); descent = SkScalarRound(height) - ascent; } m_fontMetrics.setAscent(ascent); m_fontMetrics.setDescent(descent); float xHeight; if (metrics.fXHeight) xHeight = metrics.fXHeight; else { // hack taken from the Windows port xHeight = ascent * 0.56f; } float lineGap = SkScalarToFloat(metrics.fLeading); m_fontMetrics.setLineGap(lineGap); m_fontMetrics.setXHeight(xHeight); m_fontMetrics.setLineSpacing(lroundf(ascent) + lroundf(descent) + lroundf(lineGap)); if (platformData().orientation() == Vertical && !isTextOrientationFallback()) { static const uint32_t vheaTag = SkSetFourByteTag('v', 'h', 'e', 'a'); static const uint32_t vorgTag = SkSetFourByteTag('V', 'O', 'R', 'G'); size_t vheaSize = SkFontHost::GetTableSize(fontID, vheaTag); size_t vorgSize = SkFontHost::GetTableSize(fontID, vorgTag); if ((vheaSize > 0) || (vorgSize > 0)) m_hasVerticalGlyphs = true; } // In WebKit/WebCore/platform/graphics/SimpleFontData.cpp, m_spaceWidth is // calculated for us, but we need to calculate m_maxCharWidth and // m_avgCharWidth in order for text entry widgets to be sized correctly. SkScalar xRange = metrics.fXMax - metrics.fXMin; m_maxCharWidth = SkScalarRound(xRange * SkScalarRound(m_platformData.size())); if (metrics.fAvgCharWidth) m_avgCharWidth = SkScalarRound(metrics.fAvgCharWidth); else { m_avgCharWidth = xHeight; GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (glyphPageZero) { static const UChar32 x_char = 'x'; const Glyph xGlyph = glyphPageZero->glyphDataForCharacter(x_char).glyph; if (xGlyph) m_avgCharWidth = widthForGlyph(xGlyph); } } }
void SimpleFontData::platformInit() { if (!m_platformData.size()) { m_fontMetrics.reset(); m_avgCharWidth = 0; m_maxCharWidth = 0; return; } SkPaint paint; SkPaint::FontMetrics metrics; m_platformData.setupPaint(&paint); paint.getFontMetrics(&metrics); SkTypeface* face = paint.getTypeface(); ASSERT(face); int vdmxAscent = 0, vdmxDescent = 0; bool isVDMXValid = false; #if OS(LINUX) || OS(ANDROID) // Manually digging up VDMX metrics is only applicable when bytecode hinting // using FreeType. With GDI, the metrics will already have taken this into // account (as needed). With DirectWrite or CoreText, no bytecode hinting is // ever done. This code should be pushed into FreeType (hinted font metrics). static const uint32_t vdmxTag = SkSetFourByteTag('V', 'D', 'M', 'X'); int pixelSize = m_platformData.size() + 0.5; if (!paint.isAutohinted() && (paint.getHinting() == SkPaint::kFull_Hinting || paint.getHinting() == SkPaint::kNormal_Hinting)) { size_t vdmxSize = face->getTableSize(vdmxTag); if (vdmxSize && vdmxSize < maxVDMXTableSize) { uint8_t* vdmxTable = (uint8_t*)fastMalloc(vdmxSize); if (vdmxTable && face->getTableData(vdmxTag, 0, vdmxSize, vdmxTable) == vdmxSize && parseVDMX(&vdmxAscent, &vdmxDescent, vdmxTable, vdmxSize, pixelSize)) isVDMXValid = true; fastFree(vdmxTable); } } #endif float ascent; float descent; // Beware those who step here: This code is designed to match Win32 font // metrics *exactly* (except the adjustment of ascent/descent on // Linux/Android). if (isVDMXValid) { ascent = vdmxAscent; descent = -vdmxDescent; } else { ascent = SkScalarRoundToInt(-metrics.fAscent); descent = SkScalarRoundToInt(metrics.fDescent); #if OS(LINUX) || OS(ANDROID) // When subpixel positioning is enabled, if the descent is rounded down, the // descent part of the glyph may be truncated when displayed in a 'overflow: // hidden' container. To avoid that, borrow 1 unit from the ascent when // possible. // FIXME: This can be removed if sub-pixel ascent/descent is supported. if (platformData().fontRenderStyle().useSubpixelPositioning && descent < SkScalarToFloat(metrics.fDescent) && ascent >= 1) { ++descent; --ascent; } #endif } m_fontMetrics.setAscent(ascent); m_fontMetrics.setDescent(descent); float xHeight; if (metrics.fXHeight) { xHeight = metrics.fXHeight; m_fontMetrics.setXHeight(xHeight); } else { xHeight = ascent * 0.56; // Best guess from Windows font metrics. m_fontMetrics.setXHeight(xHeight); m_fontMetrics.setHasXHeight(false); } float lineGap = SkScalarToFloat(metrics.fLeading); m_fontMetrics.setLineGap(lineGap); m_fontMetrics.setLineSpacing(lroundf(ascent) + lroundf(descent) + lroundf(lineGap)); SkScalar underlineThickness, underlinePosition; if (metrics.hasUnderlineThickness(&underlineThickness) && metrics.hasUnderlinePosition(&underlinePosition)) { m_fontMetrics.setUnderlineThickness(SkScalarToFloat(underlineThickness)); m_fontMetrics.setUnderlinePosition(SkScalarToFloat(-underlinePosition)); } if (platformData().orientation() == Vertical && !isTextOrientationFallback()) { static const uint32_t vheaTag = SkSetFourByteTag('v', 'h', 'e', 'a'); static const uint32_t vorgTag = SkSetFourByteTag('V', 'O', 'R', 'G'); size_t vheaSize = face->getTableSize(vheaTag); size_t vorgSize = face->getTableSize(vorgTag); if ((vheaSize > 0) || (vorgSize > 0)) m_hasVerticalGlyphs = true; } // In WebKit/WebCore/platform/graphics/SimpleFontData.cpp, m_spaceWidth is // calculated for us, but we need to calculate m_maxCharWidth and // m_avgCharWidth in order for text entry widgets to be sized correctly. // FIXME: This seems incorrect and should probably use fMaxCharWidth as // the code path above. SkScalar xRange = metrics.fXMax - metrics.fXMin; m_maxCharWidth = SkScalarRoundToInt(xRange * SkScalarRoundToInt(m_platformData.size())); if (metrics.fAvgCharWidth) m_avgCharWidth = SkScalarRoundToInt(metrics.fAvgCharWidth); else { m_avgCharWidth = xHeight; GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (glyphPageZero) { static const UChar32 xChar = 'x'; const Glyph xGlyph = glyphPageZero->glyphForCharacter(xChar); if (xGlyph) { // In widthForGlyph(), xGlyph will be compared with // m_zeroWidthSpaceGlyph, which isn't initialized yet here. // Initialize it with zero to make sure widthForGlyph() returns // the right width. m_zeroWidthSpaceGlyph = 0; m_avgCharWidth = widthForGlyph(xGlyph); } } } if (int unitsPerEm = face->getUnitsPerEm()) m_fontMetrics.setUnitsPerEm(unitsPerEm); }
SimpleFontData::SimpleFontData(const FontPlatformData& f, bool customFont, bool loading, SVGFontData* svgFontData) : m_font(f) , m_treatAsFixedPitch(false) #if ENABLE(SVG_FONTS) , m_svgFontData(svgFontData) #endif , m_isCustomFont(customFont) , m_isLoading(loading) , m_smallCapsFontData(0) { #if ENABLE(SVG_FONTS) && !PLATFORM(QT) if (SVGFontFaceElement* svgFontFaceElement = svgFontData ? svgFontData->svgFontFaceElement() : 0) { m_unitsPerEm = svgFontFaceElement->unitsPerEm(); double scale = f.size(); if (m_unitsPerEm) scale /= m_unitsPerEm; m_ascent = static_cast<int>(svgFontFaceElement->ascent() * scale); m_descent = static_cast<int>(svgFontFaceElement->descent() * scale); m_xHeight = static_cast<int>(svgFontFaceElement->xHeight() * scale); m_lineGap = 0.1f * f.size(); m_lineSpacing = m_ascent + m_descent + m_lineGap; m_spaceGlyph = 0; m_spaceWidth = 0; m_adjustedSpaceWidth = 0; determinePitch(); m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; return; } #endif platformInit(); GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (!glyphPageZero) { LOG_ERROR("Failed to get glyph page zero."); m_spaceGlyph = 0; m_spaceWidth = 0; m_adjustedSpaceWidth = 0; determinePitch(); m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; return; } // Nasty hack to determine if we should round or ceil space widths. // If the font is monospace or fake monospace we ceil to ensure that // every character and the space are the same width. Otherwise we round. m_spaceGlyph = glyphPageZero->glyphDataForCharacter(' ').glyph; float width = widthForGlyph(m_spaceGlyph); m_spaceWidth = width; determinePitch(); m_adjustedSpaceWidth = m_treatAsFixedPitch ? ceilf(width) : roundf(width); // Force the glyph for ZERO WIDTH SPACE to have zero width, unless it is shared with SPACE. // Helvetica is an example of a non-zero width ZERO WIDTH SPACE glyph. // See <http://bugs.webkit.org/show_bug.cgi?id=13178> // Ask for the glyph for 0 to avoid paging in ZERO WIDTH SPACE. Control characters, including 0, // are mapped to the ZERO WIDTH SPACE glyph. Glyph zeroWidthSpaceGlyph = glyphPageZero->glyphDataForCharacter(0).glyph; if (zeroWidthSpaceGlyph) { if (zeroWidthSpaceGlyph != m_spaceGlyph) m_glyphToWidthMap.setWidthForGlyph(zeroWidthSpaceGlyph, 0); else LOG_ERROR("Font maps SPACE and ZERO WIDTH SPACE to the same glyph. Glyph width not overridden."); } m_missingGlyphData.fontData = this; m_missingGlyphData.glyph = 0; }
void SimpleFontData::platformInit() { if (!m_platformData.size()) { m_fontMetrics.reset(); m_avgCharWidth = 0; m_maxCharWidth = 0; return; } SkPaint paint; SkPaint::FontMetrics metrics; m_platformData.setupPaint(&paint); paint.getFontMetrics(&metrics); const SkFontID fontID = m_platformData.uniqueID(); static const uint32_t vdmxTag = SkSetFourByteTag('V', 'D', 'M', 'X'); int pixelSize = m_platformData.size() + 0.5; int vdmxAscent, vdmxDescent; bool isVDMXValid = false; size_t vdmxSize = SkFontHost::GetTableSize(fontID, vdmxTag); if (vdmxSize && vdmxSize < maxVDMXTableSize) { uint8_t* vdmxTable = (uint8_t*) fastMalloc(vdmxSize); if (vdmxTable && SkFontHost::GetTableData(fontID, vdmxTag, 0, vdmxSize, vdmxTable) == vdmxSize && parseVDMX(&vdmxAscent, &vdmxDescent, vdmxTable, vdmxSize, pixelSize)) isVDMXValid = true; fastFree(vdmxTable); } float ascent; float descent; // Beware those who step here: This code is designed to match Win32 font // metrics *exactly* (except the adjustment of ascent/descent on Linux/Android). if (isVDMXValid) { ascent = vdmxAscent; descent = -vdmxDescent; } else { SkScalar height = -metrics.fAscent + metrics.fDescent + metrics.fLeading; ascent = SkScalarRound(-metrics.fAscent); descent = SkScalarRound(height) - ascent; #if OS(LINUX) || OS(ANDROID) // When subpixel positioning is enabled, if the descent is rounded down, the descent part // of the glyph may be truncated when displayed in a 'overflow: hidden' container. // To avoid that, borrow 1 unit from the ascent when possible. // FIXME: This can be removed if sub-pixel ascent/descent is supported. if (platformData().fontRenderStyle().useSubpixelPositioning && descent < SkScalarToFloat(metrics.fDescent) && ascent >= 1) { ++descent; --ascent; } #endif } m_fontMetrics.setAscent(ascent); m_fontMetrics.setDescent(descent); float xHeight; if (metrics.fXHeight) { xHeight = metrics.fXHeight; m_fontMetrics.setXHeight(xHeight); } else { xHeight = ascent * 0.56; // Best guess from Windows font metrics. m_fontMetrics.setXHeight(xHeight); m_fontMetrics.setHasXHeight(false); } float lineGap = SkScalarToFloat(metrics.fLeading); m_fontMetrics.setLineGap(lineGap); m_fontMetrics.setLineSpacing(lroundf(ascent) + lroundf(descent) + lroundf(lineGap)); if (platformData().orientation() == Vertical && !isTextOrientationFallback()) { static const uint32_t vheaTag = SkSetFourByteTag('v', 'h', 'e', 'a'); static const uint32_t vorgTag = SkSetFourByteTag('V', 'O', 'R', 'G'); size_t vheaSize = SkFontHost::GetTableSize(fontID, vheaTag); size_t vorgSize = SkFontHost::GetTableSize(fontID, vorgTag); if ((vheaSize > 0) || (vorgSize > 0)) m_hasVerticalGlyphs = true; } // In WebKit/WebCore/platform/graphics/SimpleFontData.cpp, m_spaceWidth is // calculated for us, but we need to calculate m_maxCharWidth and // m_avgCharWidth in order for text entry widgets to be sized correctly. SkScalar xRange = metrics.fXMax - metrics.fXMin; m_maxCharWidth = SkScalarRound(xRange * SkScalarRound(m_platformData.size())); if (metrics.fAvgCharWidth) m_avgCharWidth = SkScalarRound(metrics.fAvgCharWidth); else { m_avgCharWidth = xHeight; GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page(); if (glyphPageZero) { static const UChar32 xChar = 'x'; const Glyph xGlyph = glyphPageZero->glyphDataForCharacter(xChar).glyph; if (xGlyph) { // In widthForGlyph(), xGlyph will be compared with // m_zeroWidthSpaceGlyph, which isn't initialized yet here. // Initialize it with zero to make sure widthForGlyph() returns // the right width. m_zeroWidthSpaceGlyph = 0; m_avgCharWidth = widthForGlyph(xGlyph); } } } if (int unitsPerEm = paint.getTypeface()->getUnitsPerEm()) m_fontMetrics.setUnitsPerEm(unitsPerEm); }