C++ RenderStyle::fontCascade方法代码示例

GlyphOverflow visualOverflowForDecorations(const RenderStyle& lineStyle, const InlineTextBox* inlineTextBox)
{
    ASSERT(!inlineTextBox || inlineTextBox->lineStyle() == lineStyle);
    
    TextDecoration decoration = lineStyle.textDecorationsInEffect();
    if (decoration == TextDecorationNone)
        return GlyphOverflow();
    
    float strokeThickness = textDecorationStrokeThickness(lineStyle.fontSize());
    float controlPointDistance;
    float step;
    float wavyOffset;
        
    TextDecorationStyle decorationStyle = lineStyle.textDecorationStyle();
    float height = lineStyle.fontCascade().fontMetrics().floatHeight();
    GlyphOverflow overflowResult;
    
    if (decorationStyle == TextDecorationStyleWavy) {
        getWavyStrokeParameters(strokeThickness, controlPointDistance, step);
        wavyOffset = wavyOffsetFromDecoration();
        overflowResult.left = strokeThickness;
        overflowResult.right = strokeThickness;
    }

    // These metrics must match where underlines get drawn.
    if (decoration & TextDecorationUnderline) {
        // Compensate for the integral ceiling in GraphicsContext::computeLineBoundsAndAntialiasingModeForText()
        int underlineOffset = 1;
        underlineOffset += computeUnderlineOffset(lineStyle.textUnderlinePosition(), lineStyle.fontMetrics(), inlineTextBox, strokeThickness);
        if (decorationStyle == TextDecorationStyleWavy) {
            extendIntToFloat(overflowResult.bottom, underlineOffset + wavyOffset + controlPointDistance + strokeThickness - height);
            extendIntToFloat(overflowResult.top, -(underlineOffset + wavyOffset - controlPointDistance - strokeThickness));
        } else {
            extendIntToFloat(overflowResult.bottom, underlineOffset + strokeThickness - height);
            extendIntToFloat(overflowResult.top, -underlineOffset);
        }
    }
    if (decoration & TextDecorationOverline) {
        if (decorationStyle == TextDecorationStyleWavy) {
            extendIntToFloat(overflowResult.bottom, -wavyOffset + controlPointDistance + strokeThickness - height);
            extendIntToFloat(overflowResult.top, wavyOffset + controlPointDistance + strokeThickness);
        } else {
            extendIntToFloat(overflowResult.bottom, strokeThickness - height);
            // top is untouched
        }
    }
    if (decoration & TextDecorationLineThrough) {
        float baseline = lineStyle.fontMetrics().floatAscent();
        if (decorationStyle == TextDecorationStyleWavy) {
            extendIntToFloat(overflowResult.bottom, 2 * baseline / 3 + controlPointDistance + strokeThickness - height);
            extendIntToFloat(overflowResult.top, -(2 * baseline / 3 - controlPointDistance - strokeThickness));
        } else {
            extendIntToFloat(overflowResult.bottom, 2 * baseline / 3 + strokeThickness - height);
            extendIntToFloat(overflowResult.top, -(2 * baseline / 3));
        }
    }
    return overflowResult;
}

TextFragmentIterator::Style::Style(const RenderStyle& style)
    : font(style.fontCascade())
    , textAlign(style.textAlign())
    , collapseWhitespace(style.collapseWhiteSpace())
    , preserveNewline(style.preserveNewline())
    , wrapLines(style.autoWrap())
    , breakWordOnOverflow(style.overflowWrap() == BreakOverflowWrap && (wrapLines || preserveNewline))
    , spaceWidth(font.width(TextRun(StringView(&space, 1))))
    , tabWidth(collapseWhitespace ? 0 : style.tabSize())
    , locale(style.locale())
{
}

void RenderThemeSafari::setFontFromControlSize(StyleResolver& styleResolver, RenderStyle& style, NSControlSize controlSize) const
{
    FontDescription fontDescription;
    fontDescription.setIsAbsoluteSize(true);

    float fontSize = systemFontSizeForControlSize(controlSize);
    fontDescription.setOneFamily("Lucida Grande");
    fontDescription.setComputedSize(fontSize);
    fontDescription.setSpecifiedSize(fontSize);

    // Reset line height
    style.setLineHeight(RenderStyle::initialLineHeight());

    if (style.setFontDescription(fontDescription))
        style.fontCascade().update(&styleResolver.document().fontSelector());
}

void RenderSVGInlineText::computeNewScaledFontForStyle(const RenderObject& renderer, const RenderStyle& style, float& scalingFactor, FontCascade& scaledFont)
{
    // Alter font-size to the right on-screen value to avoid scaling the glyphs themselves, except when GeometricPrecision is specified
    scalingFactor = SVGRenderingContext::calculateScreenFontSizeScalingFactor(renderer);
    if (scalingFactor == 1 || !scalingFactor || style.fontDescription().textRenderingMode() == GeometricPrecision) {
        scalingFactor = 1;
        scaledFont = style.fontCascade();
        return;
    }

    FontDescription fontDescription(style.fontDescription());

    // FIXME: We need to better handle the case when we compute very small fonts below (below 1pt).
    fontDescription.setComputedSize(Style::computedFontSizeFromSpecifiedSizeForSVGInlineText(fontDescription.computedSize(), fontDescription.isAbsoluteSize(), scalingFactor, renderer.document()));

    scaledFont = FontCascade(fontDescription, 0, 0);
    scaledFont.update(&renderer.document().fontSelector());
}

void RenderTheme::adjustStyle(StyleResolver& styleResolver, RenderStyle& style, Element* element, bool UAHasAppearance, const BorderData& border, const FillLayer& background, const Color& backgroundColor)
{
    // Force inline and table display styles to be inline-block (except for table- which is block)
    ControlPart part = style.appearance();
    if (style.display() == INLINE || style.display() == INLINE_TABLE || style.display() == TABLE_ROW_GROUP
        || style.display() == TABLE_HEADER_GROUP || style.display() == TABLE_FOOTER_GROUP
        || style.display() == TABLE_ROW || style.display() == TABLE_COLUMN_GROUP || style.display() == TABLE_COLUMN
        || style.display() == TABLE_CELL || style.display() == TABLE_CAPTION)
        style.setDisplay(INLINE_BLOCK);
    else if (style.display() == COMPACT || style.display() == LIST_ITEM || style.display() == TABLE)
        style.setDisplay(BLOCK);

    if (UAHasAppearance && isControlStyled(style, border, background, backgroundColor)) {
        if (part == MenulistPart) {
            style.setAppearance(MenulistButtonPart);
            part = MenulistButtonPart;
        } else
            style.setAppearance(NoControlPart);
    }

    if (!style.hasAppearance())
        return;

    // Never support box-shadow on native controls.
    style.setBoxShadow(nullptr);
    
#if USE(NEW_THEME)
    switch (part) {
    case CheckboxPart:
    case InnerSpinButtonPart:
    case RadioPart:
    case PushButtonPart:
    case SquareButtonPart:
    case DefaultButtonPart:
    case ButtonPart: {
        // Border
        LengthBox borderBox(style.borderTopWidth(), style.borderRightWidth(), style.borderBottomWidth(), style.borderLeftWidth());
        borderBox = m_theme->controlBorder(part, style.fontCascade(), borderBox, style.effectiveZoom());
        if (borderBox.top().value() != static_cast<int>(style.borderTopWidth())) {
            if (borderBox.top().value())
                style.setBorderTopWidth(borderBox.top().value());
            else
                style.resetBorderTop();
        }
        if (borderBox.right().value() != static_cast<int>(style.borderRightWidth())) {
            if (borderBox.right().value())
                style.setBorderRightWidth(borderBox.right().value());
            else
                style.resetBorderRight();
        }
        if (borderBox.bottom().value() != static_cast<int>(style.borderBottomWidth())) {
            style.setBorderBottomWidth(borderBox.bottom().value());
            if (borderBox.bottom().value())
                style.setBorderBottomWidth(borderBox.bottom().value());
            else
                style.resetBorderBottom();
        }
        if (borderBox.left().value() != static_cast<int>(style.borderLeftWidth())) {
            style.setBorderLeftWidth(borderBox.left().value());
            if (borderBox.left().value())
                style.setBorderLeftWidth(borderBox.left().value());
            else
                style.resetBorderLeft();
        }

        // Padding
        LengthBox paddingBox = m_theme->controlPadding(part, style.fontCascade(), style.paddingBox(), style.effectiveZoom());
        if (paddingBox != style.paddingBox())
            style.setPaddingBox(paddingBox);

        // Whitespace
        if (m_theme->controlRequiresPreWhiteSpace(part))
            style.setWhiteSpace(PRE);
            
        // Width / Height
        // The width and height here are affected by the zoom.
        // FIXME: Check is flawed, since it doesn't take min-width/max-width into account.
        LengthSize controlSize = m_theme->controlSize(part, style.fontCascade(), LengthSize(style.width(), style.height()), style.effectiveZoom());
        if (controlSize.width() != style.width())
            style.setWidth(controlSize.width());
        if (controlSize.height() != style.height())
            style.setHeight(controlSize.height());
                
        // Min-Width / Min-Height
        LengthSize minControlSize = m_theme->minimumControlSize(part, style.fontCascade(), style.effectiveZoom());
        if (minControlSize.width() != style.minWidth())
            style.setMinWidth(minControlSize.width());
        if (minControlSize.height() != style.minHeight())
            style.setMinHeight(minControlSize.height());
                
        // Font
        if (auto themeFont = m_theme->controlFont(part, style.fontCascade(), style.effectiveZoom())) {
            // If overriding the specified font with the theme font, also override the line height with the standard line height.
            style.setLineHeight(RenderStyle::initialLineHeight());
            if (style.setFontDescription(themeFont.value()))
                style.fontCascade().update(nullptr);
        }

        // Special style that tells enabled default buttons in active windows to use the ActiveButtonText color.
        // The active window part of the test has to be done at paint time since it's not triggered by a style change.
//.........这里部分代码省略.........