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InlineLineBoxBuilder.cpp
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InlineLineBoxBuilder.cpp
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/*
* Copyright (C) 2021 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "InlineLineBoxBuilder.h"
#include "InlineLineBoxVerticalAligner.h"
#include "InlineLineBuilder.h"
#include "LayoutBoxGeometry.h"
namespace WebCore {
namespace Layout {
static std::optional<InlineLayoutUnit> horizontalAlignmentOffset(TextAlignMode textAlign, TextAlignLast textAlignLast, const LineBuilder::LineContent& lineContent, bool isLeftToRightDirection)
{
// Depending on the line’s alignment/justification, the hanging glyph can be placed outside the line box.
auto& runs = lineContent.runs;
auto contentLogicalRight = lineContent.contentLogicalRight;
auto lineLogicalRight = lineContent.lineLogicalWidth;
if (lineContent.hangingContentWidth) {
ASSERT(!runs.isEmpty());
// If white-space is set to pre-wrap, the UA must (unconditionally) hang this sequence, unless the sequence is followed
// by a forced line break, in which case it must conditionally hang the sequence is instead.
// Note that end of last line in a paragraph is considered a forced break.
auto isConditionalHanging = runs.last().isLineBreak() || lineContent.isLastLineWithInlineContent;
// In some cases, a glyph at the end of a line can conditionally hang: it hangs only if it does not otherwise fit in the line prior to justification.
if (isConditionalHanging) {
// FIXME: Conditional hanging needs partial overflow trimming at glyph boundary, one by one until they fit.
contentLogicalRight = std::min(contentLogicalRight, lineLogicalRight);
} else
contentLogicalRight -= lineContent.hangingContentWidth;
}
auto extraHorizontalSpace = lineLogicalRight - contentLogicalRight;
if (extraHorizontalSpace <= 0)
return { };
auto computedHorizontalAlignment = [&] {
// The last line before a forced break or the end of the block is aligned according to
// text-align-last.
if (lineContent.isLastLineWithInlineContent || (!runs.isEmpty() && runs.last().isLineBreak())) {
switch (textAlignLast) {
case TextAlignLast::Auto:
if (textAlign == TextAlignMode::Justify)
return TextAlignMode::Start;
return textAlign;
case TextAlignLast::Start:
return TextAlignMode::Start;
case TextAlignLast::End:
return TextAlignMode::End;
case TextAlignLast::Left:
return TextAlignMode::Left;
case TextAlignLast::Right:
return TextAlignMode::Right;
case TextAlignLast::Center:
return TextAlignMode::Center;
case TextAlignLast::Justify:
return TextAlignMode::Justify;
default:
ASSERT_NOT_REACHED();
return TextAlignMode::Start;
}
}
// All other lines are aligned according to text-align.
return textAlign;
};
switch (computedHorizontalAlignment()) {
case TextAlignMode::Left:
case TextAlignMode::WebKitLeft:
if (!isLeftToRightDirection)
return extraHorizontalSpace;
FALLTHROUGH;
case TextAlignMode::Start:
return { };
case TextAlignMode::Right:
case TextAlignMode::WebKitRight:
if (!isLeftToRightDirection)
return { };
FALLTHROUGH;
case TextAlignMode::End:
return extraHorizontalSpace;
case TextAlignMode::Center:
case TextAlignMode::WebKitCenter:
return extraHorizontalSpace / 2;
case TextAlignMode::Justify:
// TextAlignMode::Justify is a run alignment (and we only do inline box alignment here)
return { };
default:
ASSERT_NOT_IMPLEMENTED_YET();
return { };
}
ASSERT_NOT_REACHED();
return { };
}
LineBoxBuilder::LineBoxBuilder(const InlineFormattingContext& inlineFormattingContext)
: m_inlineFormattingContext(inlineFormattingContext)
{
}
LineBox LineBoxBuilder::build(const LineBuilder::LineContent& lineContent, size_t lineIndex)
{
auto& rootStyle = lineIndex ? rootBox().firstLineStyle() : rootBox().style();
auto rootInlineBoxAlignmentOffset = valueOrDefault(Layout::horizontalAlignmentOffset(rootStyle.textAlign(), rootStyle.textAlignLast(), lineContent, lineContent.inlineBaseDirection == TextDirection::LTR));
// FIXME: The overflowing hanging content should be part of the ink overflow.
auto lineBox = LineBox { rootBox(), rootInlineBoxAlignmentOffset, lineContent.contentLogicalWidth - lineContent.hangingContentWidth, lineIndex, lineContent.nonSpanningInlineLevelBoxCount };
constructInlineLevelBoxes(lineBox, lineContent, lineIndex);
adjustIdeographicBaselineIfApplicable(lineBox, lineIndex);
auto lineBoxLogicalHeight = LineBoxVerticalAligner { formattingContext() }.computeLogicalHeightAndAlign(lineBox);
lineBox.setLogicalRect({ lineContent.lineLogicalTopLeft, lineContent.lineLogicalWidth, lineBoxLogicalHeight });
return lineBox;
}
void LineBoxBuilder::adjustLayoutBoundsWithFallbackFonts(InlineLevelBox& inlineBox, const TextUtil::FallbackFontList& fallbackFontsForContent, FontBaseline fontBaseline) const
{
ASSERT(!fallbackFontsForContent.isEmpty());
ASSERT(inlineBox.isInlineBox());
if (!inlineBox.isPreferredLineHeightFontMetricsBased())
return;
// https://www.w3.org/TR/css-inline-3/#inline-height
// When the computed line-height is normal, the layout bounds of an inline box encloses all its glyphs, going from the highest A to the deepest D.
auto maxAscent = InlineLayoutUnit { };
auto maxDescent = InlineLayoutUnit { };
// If line-height computes to normal and either text-edge is leading or this is the root inline box,
// the font's line gap metric may also be incorporated into A and D by adding half to each side as half-leading.
// FIXME: We don't support the text-edge property yet, but its initial value is 'leading' which makes the line-gap adjustment always on.
auto isTextEdgeLeading = true;
auto shouldUseLineGapToAdjustAscentDescent = inlineBox.isRootInlineBox() || isTextEdgeLeading;
for (auto* font : fallbackFontsForContent) {
auto& fontMetrics = font->fontMetrics();
InlineLayoutUnit ascent = fontMetrics.ascent(fontBaseline);
InlineLayoutUnit descent = fontMetrics.descent(fontBaseline);
if (shouldUseLineGapToAdjustAscentDescent) {
auto logicalHeight = ascent + descent;
auto halfLineGap = (fontMetrics.lineSpacing() - logicalHeight) / 2;
ascent = ascent + halfLineGap;
descent = descent + halfLineGap;
}
maxAscent = std::max(maxAscent, ascent);
maxDescent = std::max(maxDescent, descent);
}
// We need floor/ceil to match legacy layout integral positioning.
auto layoutBounds = *inlineBox.layoutBounds();
inlineBox.setLayoutBounds({ std::max(layoutBounds.ascent, floorf(maxAscent)), std::max(layoutBounds.descent, ceilf(maxDescent)) });
}
TextUtil::FallbackFontList LineBoxBuilder::collectFallbackFonts(const InlineLevelBox& parentInlineBox, const Line::Run& run, const RenderStyle& style)
{
ASSERT(parentInlineBox.isInlineBox());
auto& inlineTextBox = downcast<InlineTextBox>(run.layoutBox());
if (inlineTextBox.canUseSimplifiedContentMeasuring()) {
// Simplified text measuring works with primary font only.
return { };
}
auto text = *run.textContent();
auto fallbackFonts = TextUtil::fallbackFontsForText(StringView(inlineTextBox.content()).substring(text.start, text.length), style, text.needsHyphen ? TextUtil::IncludeHyphen::Yes : TextUtil::IncludeHyphen::No);
if (fallbackFonts.isEmpty())
return { };
auto fallbackFontsForInlineBoxes = m_fallbackFontsForInlineBoxes.get(&parentInlineBox);
auto numberOfFallbackFontsForInlineBox = fallbackFontsForInlineBoxes.size();
for (auto* font : fallbackFonts) {
fallbackFontsForInlineBoxes.add(font);
m_fallbackFontRequiresIdeographicBaseline = m_fallbackFontRequiresIdeographicBaseline || font->hasVerticalGlyphs();
}
if (fallbackFontsForInlineBoxes.size() != numberOfFallbackFontsForInlineBox)
m_fallbackFontsForInlineBoxes.set(&parentInlineBox, fallbackFontsForInlineBoxes);
return fallbackFonts;
}
struct AscentAndDescent {
InlineLayoutUnit ascent { 0 };
InlineLayoutUnit descent { 0 };
InlineLayoutUnit height() const { return ascent + descent; }
};
struct TextMetrics {
AscentAndDescent ascentAndDescent { };
InlineLayoutUnit lineSpacing { 0 };
std::optional<InlineLayoutUnit> preferredLineHeight { };
};
static TextMetrics primaryFontMetricsForInlineBox(const InlineLevelBox& inlineBox, FontBaseline fontBaseline = AlphabeticBaseline)
{
ASSERT(inlineBox.isInlineBox());
auto& fontMetrics = inlineBox.primarymetricsOfPrimaryFont();
InlineLayoutUnit ascent = fontMetrics.ascent(fontBaseline);
InlineLayoutUnit descent = fontMetrics.descent(fontBaseline);
InlineLayoutUnit lineSpacing = fontMetrics.lineSpacing();
return { { ascent, descent }, lineSpacing, inlineBox.isPreferredLineHeightFontMetricsBased() ? std::nullopt : std::make_optional(inlineBox.preferredLineHeight()) };
}
void LineBoxBuilder::setVerticalPropertiesForInlineLevelBox(const LineBox& lineBox, InlineLevelBox& inlineLevelBox) const
{
auto setAscentAndDescent = [&] (auto ascentAndDescent) {
inlineLevelBox.setAscent(ascentAndDescent.ascent);
inlineLevelBox.setDescent(ascentAndDescent.descent);
};
auto setLayoutBounds = [&] (auto& textMetrics) {
auto logicalHeight = textMetrics.ascentAndDescent.ascent + textMetrics.ascentAndDescent.descent;
auto halfLeading = InlineLayoutUnit { };
if (textMetrics.preferredLineHeight) {
// If line-height computes to normal and either text-edge is leading or this is the root inline box,
// the font’s line gap metric may also be incorporated into A and D by adding half to each side as half-leading.
// https://www.w3.org/TR/css-inline-3/#inline-height
// Since text-edge is not supported yet and the initial value is leading, we should just apply it to
// all inline boxes.
halfLeading = (*textMetrics.preferredLineHeight - logicalHeight) / 2;
} else {
// Preferred line height is purely font metrics based (i.e glyphs stretch the line).
halfLeading = (textMetrics.lineSpacing - logicalHeight) / 2;
}
inlineLevelBox.setLayoutBounds({ floorf(textMetrics.ascentAndDescent.ascent + halfLeading), ceilf(textMetrics.ascentAndDescent.descent + halfLeading) });
};
if (inlineLevelBox.isInlineBox()) {
auto textMetrics = primaryFontMetricsForInlineBox(inlineLevelBox, lineBox.baselineType());
setLayoutBounds(textMetrics);
// We need floor/ceil to match legacy layout integral positioning.
setAscentAndDescent(AscentAndDescent { floorf(textMetrics.ascentAndDescent.ascent), ceilf(textMetrics.ascentAndDescent.descent) });
inlineLevelBox.setLogicalHeight(textMetrics.ascentAndDescent.height());
return;
}
if (inlineLevelBox.isLineBreakBox()) {
auto parentTextMetrics = primaryFontMetricsForInlineBox(lineBox.inlineLevelBoxForLayoutBox(inlineLevelBox.layoutBox().parent()), lineBox.baselineType());
setLayoutBounds(parentTextMetrics);
// We need floor/ceil to match legacy layout integral positioning.
setAscentAndDescent(AscentAndDescent { floorf(parentTextMetrics.ascentAndDescent.ascent), ceilf(parentTextMetrics.ascentAndDescent.descent) });
inlineLevelBox.setLogicalHeight(parentTextMetrics.ascentAndDescent.height());
return;
}
if (inlineLevelBox.isListMarker()) {
// Special list marker handling. Text driven list markers behave as text when it comes to layout bounds.
auto& layoutBox = inlineLevelBox.layoutBox();
auto& listMarkerBoxGeometry = formattingContext().geometryForBox(layoutBox);
auto marginBoxHeight = listMarkerBoxGeometry.marginBoxHeight();
inlineLevelBox.setLogicalHeight(marginBoxHeight);
if (lineBox.baselineType() == IdeographicBaseline) {
// FIXME: We should rely on the integration baseline.
auto parentTextMetrics = primaryFontMetricsForInlineBox(lineBox.inlineLevelBoxForLayoutBox(inlineLevelBox.layoutBox().parent()), lineBox.baselineType());
setLayoutBounds(parentTextMetrics);
// We need floor/ceil to match legacy layout integral positioning.
setAscentAndDescent(AscentAndDescent { floorf(parentTextMetrics.ascentAndDescent.ascent), ceilf(parentTextMetrics.ascentAndDescent.descent) });
return;
}
if (auto ascent = downcast<ElementBox>(layoutBox).baselineForIntegration()) {
auto textMetrics = TextMetrics { { *ascent, marginBoxHeight - *ascent }, { }, { } };
setLayoutBounds(textMetrics);
// We need floor/ceil to match legacy layout integral positioning.
setAscentAndDescent(AscentAndDescent { floorf(textMetrics.ascentAndDescent.ascent), ceilf(textMetrics.ascentAndDescent.descent) });
return;
}
setAscentAndDescent(AscentAndDescent { marginBoxHeight, { } });
return;
}
if (inlineLevelBox.isAtomicInlineLevelBox()) {
auto& layoutBox = inlineLevelBox.layoutBox();
auto& inlineLevelBoxGeometry = formattingContext().geometryForBox(layoutBox);
auto marginBoxHeight = inlineLevelBoxGeometry.marginBoxHeight();
auto ascent = [&]() -> InlineLayoutUnit {
if (layoutState().shouldNotSynthesizeInlineBlockBaseline())
return downcast<ElementBox>(layoutBox).baselineForIntegration().value_or(marginBoxHeight);
if (layoutBox.isInlineBlockBox()) {
// The baseline of an 'inline-block' is the baseline of its last line box in the normal flow, unless it has either no in-flow line boxes or
// if its 'overflow' property has a computed value other than 'visible', in which case the baseline is the bottom margin edge.
auto synthesizeBaseline = !layoutBox.establishesInlineFormattingContext() || !layoutBox.style().isOverflowVisible();
if (synthesizeBaseline)
return marginBoxHeight;
auto& formattingState = layoutState().formattingStateForInlineFormattingContext(downcast<ElementBox>(layoutBox));
auto& lastLine = formattingState.lines().last();
auto inlineBlockBaseline = lastLine.top() + lastLine.baseline();
return inlineLevelBoxGeometry.marginBefore() + inlineLevelBoxGeometry.borderBefore() + inlineLevelBoxGeometry.paddingBefore().value_or(0) + inlineBlockBaseline;
}
return marginBoxHeight;
}();
setAscentAndDescent(AscentAndDescent { ascent, marginBoxHeight - ascent });
inlineLevelBox.setLogicalHeight(marginBoxHeight);
return;
}
ASSERT_NOT_REACHED();
}
void LineBoxBuilder::constructInlineLevelBoxes(LineBox& lineBox, const LineBuilder::LineContent& lineContent, size_t lineIndex)
{
auto& rootInlineBox = lineBox.rootInlineBox();
setVerticalPropertiesForInlineLevelBox(lineBox, rootInlineBox);
auto styleToUse = [&] (const auto& layoutBox) -> const RenderStyle& {
return !lineIndex ? layoutBox.firstLineStyle() : layoutBox.style();
};
auto lineHasContent = false;
for (auto& run : lineContent.runs) {
auto& layoutBox = run.layoutBox();
auto& style = styleToUse(layoutBox);
auto runHasContent = [&] () -> bool {
ASSERT(!lineHasContent);
if (run.isContentful())
return true;
if (run.isText() || run.isWordBreakOpportunity())
return false;
ASSERT(run.isInlineBox());
if (run.isLineSpanningInlineBoxStart()) {
// We already handled inline box decoration at the non-spanning start.
return false;
}
auto& inlineBoxGeometry = formattingContext().geometryForBox(layoutBox);
// Even negative horizontal margin makes the line "contentful".
if (run.isInlineBoxStart())
return inlineBoxGeometry.marginStart() || inlineBoxGeometry.borderStart() || inlineBoxGeometry.paddingStart().value_or(0_lu);
if (run.isInlineBoxEnd())
return inlineBoxGeometry.marginEnd() || inlineBoxGeometry.borderEnd() || inlineBoxGeometry.paddingEnd().value_or(0_lu);
ASSERT_NOT_REACHED();
return true;
};
lineHasContent = lineHasContent || runHasContent();
auto logicalLeft = rootInlineBox.logicalLeft() + run.logicalLeft();
if (run.isBox() || run.isListMarker()) {
auto& inlineLevelBoxGeometry = formattingContext().geometryForBox(layoutBox);
logicalLeft += std::max(0_lu, inlineLevelBoxGeometry.marginStart());
auto atomicInlineLevelBox = InlineLevelBox::createAtomicInlineLevelBox(layoutBox, style, logicalLeft, inlineLevelBoxGeometry.borderBoxWidth());
setVerticalPropertiesForInlineLevelBox(lineBox, atomicInlineLevelBox);
lineBox.addInlineLevelBox(WTFMove(atomicInlineLevelBox));
continue;
}
if (run.isLineSpanningInlineBoxStart()) {
auto marginStart = InlineLayoutUnit { };
#if ENABLE(CSS_BOX_DECORATION_BREAK)
if (style.boxDecorationBreak() == BoxDecorationBreak::Clone)
marginStart = formattingContext().geometryForBox(layoutBox).marginStart();
#endif
auto adjustedLogicalStart = logicalLeft + std::max(0.0f, marginStart);
auto logicalWidth = rootInlineBox.logicalWidth() - adjustedLogicalStart;
auto inlineBox = InlineLevelBox::createInlineBox(layoutBox, style, adjustedLogicalStart, logicalWidth, InlineLevelBox::LineSpanningInlineBox::Yes);
setVerticalPropertiesForInlineLevelBox(lineBox, inlineBox);
lineBox.addInlineLevelBox(WTFMove(inlineBox));
continue;
}
if (run.isInlineBoxStart()) {
// At this point we don't know yet how wide this inline box is. Let's assume it's as long as the line is
// and adjust it later if we come across an inlineBoxEnd run (see below).
// Inline box run is based on margin box. Let's convert it to border box.
auto marginStart = formattingContext().geometryForBox(layoutBox).marginStart();
logicalLeft += std::max(0_lu, marginStart);
auto initialLogicalWidth = rootInlineBox.logicalWidth() - (logicalLeft - rootInlineBox.logicalLeft());
ASSERT(initialLogicalWidth >= 0 || lineContent.hangingContentWidth || std::isnan(initialLogicalWidth));
initialLogicalWidth = std::max(initialLogicalWidth, 0.f);
auto inlineBox = InlineLevelBox::createInlineBox(layoutBox, style, logicalLeft, initialLogicalWidth);
inlineBox.setIsFirstBox();
setVerticalPropertiesForInlineLevelBox(lineBox, inlineBox);
lineBox.addInlineLevelBox(WTFMove(inlineBox));
continue;
}
if (run.isInlineBoxEnd()) {
// Adjust the logical width when the inline box closes on this line.
// Note that margin end does not affect the logical width (e.g. positive margin right does not make the run wider).
auto& inlineBox = lineBox.inlineLevelBoxForLayoutBox(layoutBox);
ASSERT(inlineBox.isInlineBox());
// Inline box run is based on margin box. Let's convert it to border box.
// Negative margin end makes the run have negative width.
auto marginEndAdjustemnt = -formattingContext().geometryForBox(layoutBox).marginEnd();
auto logicalWidth = run.logicalWidth() + marginEndAdjustemnt;
auto inlineBoxLogicalRight = logicalLeft + logicalWidth;
// When the content pulls the </span> to the logical left direction (e.g. negative letter space)
// make sure we don't end up with negative logical width on the inline box.
inlineBox.setLogicalWidth(std::max(0.f, inlineBoxLogicalRight - inlineBox.logicalLeft()));
inlineBox.setIsLastBox();
continue;
}
if (run.isText()) {
auto& parentInlineBox = lineBox.inlineLevelBoxForLayoutBox(layoutBox.parent());
parentInlineBox.setHasContent();
if (auto fallbackFonts = collectFallbackFonts(parentInlineBox, run, style); !fallbackFonts.isEmpty()) {
// Adjust non-empty inline box height when glyphs from the non-primary font stretch the box.
adjustLayoutBoundsWithFallbackFonts(parentInlineBox, fallbackFonts, AlphabeticBaseline);
}
continue;
}
if (run.isSoftLineBreak()) {
lineBox.inlineLevelBoxForLayoutBox(layoutBox.parent()).setHasContent();
continue;
}
if (run.isHardLineBreak()) {
auto lineBreakBox = InlineLevelBox::createLineBreakBox(layoutBox, style, logicalLeft);
setVerticalPropertiesForInlineLevelBox(lineBox, lineBreakBox);
lineBox.addInlineLevelBox(WTFMove(lineBreakBox));
continue;
}
if (run.isWordBreakOpportunity()) {
lineBox.addInlineLevelBox(InlineLevelBox::createGenericInlineLevelBox(layoutBox, style, logicalLeft));
continue;
}
ASSERT_NOT_REACHED();
}
lineBox.setHasContent(lineHasContent);
}
void LineBoxBuilder::adjustIdeographicBaselineIfApplicable(LineBox& lineBox, size_t lineIndex)
{
// Re-compute the ascent/descent values for the inline boxes on the line (including the root inline box)
// when the style/content needs ideographic baseline setup in vertical writing mode.
auto& rootInlineBox = lineBox.rootInlineBox();
auto lineNeedsIdeographicBaseline = [&] {
auto styleToUse = [&] (auto& inlineLevelBox) -> const RenderStyle& {
return !lineIndex ? inlineLevelBox.layoutBox().firstLineStyle() : inlineLevelBox.layoutBox().style();
};
auto& rootInlineBoxStyle = styleToUse(rootInlineBox);
if (rootInlineBoxStyle.isHorizontalWritingMode())
return false;
auto primaryFontRequiresIdeographicBaseline = [&] (auto& style) {
return style.fontDescription().orientation() == FontOrientation::Vertical || style.fontCascade().primaryFont().hasVerticalGlyphs();
};
if (m_fallbackFontRequiresIdeographicBaseline || primaryFontRequiresIdeographicBaseline(rootInlineBoxStyle))
return true;
for (auto& inlineLevelBox : lineBox.nonRootInlineLevelBoxes()) {
if (inlineLevelBox.isInlineBox() && primaryFontRequiresIdeographicBaseline(styleToUse(inlineLevelBox)))
return true;
}
return false;
};
if (!lineNeedsIdeographicBaseline())
return;
lineBox.setBaselineType(IdeographicBaseline);
auto adjustLayoutBoundsWithIdeographicBaseline = [&] (auto& inlineLevelBox) {
auto initiatesLayoutBoundsChange = inlineLevelBox.isInlineBox() || inlineLevelBox.isAtomicInlineLevelBox() || inlineLevelBox.isLineBreakBox();
if (!initiatesLayoutBoundsChange)
return;
if (inlineLevelBox.isInlineBox() || inlineLevelBox.isLineBreakBox() || (inlineLevelBox.isListMarker() && !downcast<ElementBox>(inlineLevelBox.layoutBox()).isListMarkerImage()))
setVerticalPropertiesForInlineLevelBox(lineBox, inlineLevelBox);
else if (inlineLevelBox.isAtomicInlineLevelBox()) {
auto inlineLevelBoxHeight = inlineLevelBox.logicalHeight();
InlineLayoutUnit ideographicBaseline = roundToInt(inlineLevelBoxHeight / 2);
// Move the baseline position but keep the same logical height.
inlineLevelBox.setAscent(ideographicBaseline);
}
auto needsFontFallbackAdjustment = inlineLevelBox.isInlineBox() || inlineLevelBox.isLineBreakBox();
if (needsFontFallbackAdjustment) {
if (auto fallbackFonts = m_fallbackFontsForInlineBoxes.get(&inlineLevelBox); !fallbackFonts.isEmpty())
adjustLayoutBoundsWithFallbackFonts(inlineLevelBox, fallbackFonts, IdeographicBaseline);
}
};
adjustLayoutBoundsWithIdeographicBaseline(rootInlineBox);
for (auto& inlineLevelBox : lineBox.nonRootInlineLevelBoxes()) {
if (inlineLevelBox.isAtomicInlineLevelBox()) {
auto& layoutBox = inlineLevelBox.layoutBox();
if (layoutBox.isInlineTableBox()) {
// This is the integration codepath where inline table boxes are represented as atomic inline boxes.
// Integration codepath sets ideographic baseline by default for non-horizontal content.
continue;
}
auto isInlineBlockWithNonSyntheticBaseline = layoutBox.isInlineBlockBox() && downcast<ElementBox>(layoutBox).baselineForIntegration().has_value();
if (isInlineBlockWithNonSyntheticBaseline && !layoutBox.style().isHorizontalWritingMode())
continue;
}
adjustLayoutBoundsWithIdeographicBaseline(inlineLevelBox);
}
}
}
}