LibWeb: Layout inline elements respective of writing-mode

Use the `writing-mode` property to determine what values should be used
for computing each element's rect on the screen. If it is a vertical
mode, swap the inline and block, lengths and offsets.

This only lays out whole inline formatting contexts vertically, and does
not currently support mixing the two orientations in a single context.
This commit is contained in:
BenJilks 2024-10-29 11:32:59 +00:00 committed by Alexander Kalenik
parent ede9012723
commit 80e7e6dd7d
Notes: github-actions[bot] 2024-11-03 16:03:04 +00:00
9 changed files with 65 additions and 12 deletions

View file

@ -0,0 +1,11 @@
Viewport <#document> at (0,0) content-size 800x600 children: not-inline
BlockContainer <html> at (0,0) content-size 800x186.265625 [BFC] children: not-inline
BlockContainer <body> at (8,8) content-size 784x170.265625 children: inline
frag 0 from TextNode start: 0, length: 24, rect: [775,8 17x170.265625] baseline: 13.296875
"Well, hello friends! :-)"
TextNode <#text>
ViewportPaintable (Viewport<#document>) [0,0 800x600]
PaintableWithLines (BlockContainer<HTML>) [0,0 800x186.265625]
PaintableWithLines (BlockContainer<BODY>) [8,8 784x170.265625]
TextPaintable (TextNode<#text>)

View file

@ -0,0 +1,6 @@
<!DOCTYPE html>
<style>
body {
writing-mode: vertical-rl;
}
</style>Well, hello friends! :-)

View file

@ -250,9 +250,10 @@ void InlineFormattingContext::generate_line_boxes()
line_boxes.clear_with_capacity();
auto direction = m_context_box->computed_values().direction();
auto writing_mode = m_context_box->computed_values().writing_mode();
InlineLevelIterator iterator(*this, m_state, containing_block(), m_containing_block_used_values, m_layout_mode);
LineBuilder line_builder(*this, m_state, m_containing_block_used_values, direction);
LineBuilder line_builder(*this, m_state, m_containing_block_used_values, direction, writing_mode);
// NOTE: When we ignore collapsible whitespace chunks at the start of a line,
// we have to remember how much start margin that chunk had in the inline

View file

@ -16,6 +16,27 @@
namespace Web::Layout {
CSSPixels LineBox::width() const
{
if (m_writing_mode != CSS::WritingMode::HorizontalTb)
return m_block_length;
return m_inline_length;
}
CSSPixels LineBox::height() const
{
if (m_writing_mode != CSS::WritingMode::HorizontalTb)
return m_inline_length;
return m_block_length;
}
CSSPixels LineBox::bottom() const
{
if (m_writing_mode != CSS::WritingMode::HorizontalTb)
return m_inline_length;
return m_bottom;
}
void LineBox::add_fragment(Node const& layout_node, int start, int length, CSSPixels leading_size, CSSPixels trailing_size, CSSPixels leading_margin, CSSPixels trailing_margin, CSSPixels content_width, CSSPixels content_height, CSSPixels border_box_top, CSSPixels border_box_bottom, RefPtr<Gfx::GlyphRun> glyph_run)
{
bool text_align_is_justify = layout_node.computed_values().text_align() == CSS::TextAlign::Justify;
@ -27,7 +48,7 @@ void LineBox::add_fragment(Node const& layout_node, int start, int length, CSSPi
} else {
CSSPixels inline_offset = leading_margin + leading_size + m_inline_length;
CSSPixels block_offset = 0;
m_fragments.append(LineBoxFragment { layout_node, start, length, inline_offset, block_offset, content_width, content_height, border_box_top, m_direction, move(glyph_run) });
m_fragments.append(LineBoxFragment { layout_node, start, length, inline_offset, block_offset, content_width, content_height, border_box_top, m_direction, m_writing_mode, move(glyph_run) });
}
m_inline_length += leading_margin + leading_size + content_width + trailing_size + trailing_margin;
m_block_length = max(m_block_length, content_height + border_box_top + border_box_bottom);

View file

@ -13,14 +13,15 @@ namespace Web::Layout {
class LineBox {
public:
LineBox(CSS::Direction direction)
LineBox(CSS::Direction direction, CSS::WritingMode writing_mode)
: m_direction(direction)
, m_writing_mode(writing_mode)
{
}
CSSPixels width() const { return m_inline_length; }
CSSPixels height() const { return m_block_length; }
CSSPixels bottom() const { return m_bottom; }
CSSPixels width() const;
CSSPixels height() const;
CSSPixels bottom() const;
CSSPixels inline_length() const { return m_inline_length; }
CSSPixels block_length() const { return m_block_length; }
@ -49,6 +50,7 @@ private:
CSSPixels m_bottom { 0 };
CSSPixels m_baseline { 0 };
CSS::Direction m_direction { CSS::Direction::Ltr };
CSS::WritingMode m_writing_mode { CSS::WritingMode::HorizontalTb };
// The amount of available width that was originally available when creating this line box. Used for text justification.
AvailableSize m_original_available_width { AvailableSize::make_indefinite() };

View file

@ -13,7 +13,7 @@
namespace Web::Layout {
LineBoxFragment::LineBoxFragment(Node const& layout_node, int start, int length, CSSPixels inline_offset, CSSPixels block_offset, CSSPixels inline_length, CSSPixels block_length, CSSPixels border_box_top, CSS::Direction direction, RefPtr<Gfx::GlyphRun> glyph_run)
LineBoxFragment::LineBoxFragment(Node const& layout_node, int start, int length, CSSPixels inline_offset, CSSPixels block_offset, CSSPixels inline_length, CSSPixels block_length, CSSPixels border_box_top, CSS::Direction direction, CSS::WritingMode writing_mode, RefPtr<Gfx::GlyphRun> glyph_run)
: m_layout_node(layout_node)
, m_start(start)
, m_length(length)
@ -23,6 +23,7 @@ LineBoxFragment::LineBoxFragment(Node const& layout_node, int start, int length,
, m_block_length(block_length)
, m_border_box_top(border_box_top)
, m_direction(direction)
, m_writing_mode(writing_mode)
, m_glyph_run(move(glyph_run))
{
if (m_glyph_run) {
@ -34,11 +35,15 @@ LineBoxFragment::LineBoxFragment(Node const& layout_node, int start, int length,
CSSPixelPoint LineBoxFragment::offset() const
{
if (m_writing_mode != CSS::WritingMode::HorizontalTb)
return { m_block_offset, m_inline_offset };
return { m_inline_offset, m_block_offset };
}
CSSPixelSize LineBoxFragment::size() const
{
if (m_writing_mode != CSS::WritingMode::HorizontalTb)
return { m_block_length, m_inline_length };
return { m_inline_length, m_block_length };
}

View file

@ -19,7 +19,7 @@ class LineBoxFragment {
friend class LineBox;
public:
LineBoxFragment(Node const& layout_node, int start, int length, CSSPixels inline_offset, CSSPixels block_offset, CSSPixels inline_length, CSSPixels block_length, CSSPixels border_box_top, CSS::Direction, RefPtr<Gfx::GlyphRun>);
LineBoxFragment(Node const& layout_node, int start, int length, CSSPixels inline_offset, CSSPixels block_offset, CSSPixels inline_length, CSSPixels block_length, CSSPixels border_box_top, CSS::Direction, CSS::WritingMode, RefPtr<Gfx::GlyphRun>);
Node const& layout_node() const { return m_layout_node; }
int start() const { return m_start; }
@ -70,6 +70,7 @@ private:
CSSPixels m_border_box_top { 0 };
CSSPixels m_baseline { 0 };
CSS::Direction m_direction { CSS::Direction::Ltr };
CSS::WritingMode m_writing_mode { CSS::WritingMode::HorizontalTb };
RefPtr<Gfx::GlyphRun> m_glyph_run;
float m_insert_position { 0 };

View file

@ -10,11 +10,12 @@
namespace Web::Layout {
LineBuilder::LineBuilder(InlineFormattingContext& context, LayoutState& layout_state, LayoutState::UsedValues& containing_block_used_values, CSS::Direction direction)
LineBuilder::LineBuilder(InlineFormattingContext& context, LayoutState& layout_state, LayoutState::UsedValues& containing_block_used_values, CSS::Direction direction, CSS::WritingMode writing_mode)
: m_context(context)
, m_layout_state(layout_state)
, m_containing_block_used_values(containing_block_used_values)
, m_direction(direction)
, m_writing_mode(writing_mode)
{
m_text_indent = m_context.containing_block().computed_values().text_indent().to_px(m_context.containing_block(), m_containing_block_used_values.content_width());
begin_new_line(false);
@ -38,7 +39,7 @@ void LineBuilder::break_line(ForcedBreak forced_break, Optional<CSSPixels> next_
size_t break_count = 0;
bool floats_intrude_at_current_y = false;
do {
m_containing_block_used_values.line_boxes.append(LineBox(m_direction));
m_containing_block_used_values.line_boxes.append(LineBox(m_direction, m_writing_mode));
begin_new_line(true, break_count == 0);
break_count++;
floats_intrude_at_current_y = m_context.any_floats_intrude_at_block_offset(m_current_block_offset);
@ -83,7 +84,7 @@ LineBox& LineBuilder::ensure_last_line_box()
{
auto& line_boxes = m_containing_block_used_values.line_boxes;
if (line_boxes.is_empty())
line_boxes.append(LineBox(m_direction));
line_boxes.append(LineBox(m_direction, m_writing_mode));
return line_boxes.last();
}
@ -179,6 +180,10 @@ void LineBuilder::update_last_line()
// FIXME: Respect inline direction.
CSSPixels excess_inline_space = m_available_width_for_current_line.to_px_or_zero() - line_box.inline_length();
if (m_writing_mode != CSS::WritingMode::HorizontalTb) {
block_offset = m_available_width_for_current_line.to_px_or_zero() - line_box.block_length();
}
// If (after justification, if any) the inline contents of a line box are too long to fit within it,
// then the contents are start-aligned: any content that doesn't fit overflows the line boxs end edge.
if (excess_inline_space > 0) {

View file

@ -15,7 +15,7 @@ class LineBuilder {
AK_MAKE_NONMOVABLE(LineBuilder);
public:
LineBuilder(InlineFormattingContext&, LayoutState&, LayoutState::UsedValues& containing_block_used_values, CSS::Direction);
LineBuilder(InlineFormattingContext&, LayoutState&, LayoutState::UsedValues& containing_block_used_values, CSS::Direction, CSS::WritingMode);
~LineBuilder();
enum class ForcedBreak {
@ -64,6 +64,7 @@ private:
CSSPixels m_max_height_on_current_line { 0 };
CSSPixels m_text_indent { 0 };
CSS::Direction m_direction { CSS::Direction::Ltr };
CSS::WritingMode m_writing_mode { CSS::WritingMode::HorizontalTb };
bool m_last_line_needs_update { false };
};