mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2025-04-29 07:48:47 +00:00
eb77e680ed
In order for this to work nicely, I made the line box classes use float instead of int for its geometry information. Justification works by distributing all of the whitespace on the line (including the trailing whitespace before the line break) evenly across the spaces in-between words. We should probably use floating point (or maybe fixed point?) for all the layout metrics stuff. But one thing at a time. :^)
317 lines
12 KiB
C++
317 lines
12 KiB
C++
#include <LibGUI/GPainter.h>
|
|
#include <LibHTML/CSS/StyleResolver.h>
|
|
#include <LibHTML/DOM/Element.h>
|
|
#include <LibHTML/Layout/LayoutBlock.h>
|
|
#include <LibHTML/Layout/LayoutInline.h>
|
|
#include <LibHTML/Layout/LayoutReplaced.h>
|
|
#include <LibHTML/Layout/LayoutText.h>
|
|
#include <math.h>
|
|
|
|
LayoutBlock::LayoutBlock(const Node* node, NonnullRefPtr<StyleProperties> style)
|
|
: LayoutBox(node, move(style))
|
|
{
|
|
}
|
|
|
|
LayoutBlock::~LayoutBlock()
|
|
{
|
|
}
|
|
|
|
LayoutNode& LayoutBlock::inline_wrapper()
|
|
{
|
|
if (!last_child() || !last_child()->is_block() || last_child()->node() != nullptr) {
|
|
append_child(adopt(*new LayoutBlock(nullptr, style_for_anonymous_block())));
|
|
last_child()->set_children_are_inline(true);
|
|
}
|
|
return *last_child();
|
|
}
|
|
|
|
void LayoutBlock::layout()
|
|
{
|
|
compute_width();
|
|
compute_position();
|
|
|
|
if (children_are_inline())
|
|
layout_inline_children();
|
|
else
|
|
layout_block_children();
|
|
|
|
compute_height();
|
|
}
|
|
|
|
void LayoutBlock::layout_block_children()
|
|
{
|
|
ASSERT(!children_are_inline());
|
|
int content_height = 0;
|
|
for_each_child([&](auto& child) {
|
|
// FIXME: What should we do here? Something like a <table> might have a bunch of useless text children..
|
|
if (child.is_inline())
|
|
return;
|
|
auto& child_block = static_cast<LayoutBlock&>(child);
|
|
child_block.layout();
|
|
content_height = child_block.rect().bottom() + child_block.box_model().full_margin().bottom - rect().top();
|
|
});
|
|
rect().set_height(content_height);
|
|
}
|
|
|
|
void LayoutBlock::layout_inline_children()
|
|
{
|
|
ASSERT(children_are_inline());
|
|
m_line_boxes.clear();
|
|
for_each_child([&](auto& child) {
|
|
ASSERT(child.is_inline());
|
|
child.split_into_lines(*this);
|
|
});
|
|
|
|
int min_line_height = style().line_height();
|
|
int content_height = 0;
|
|
|
|
// FIXME: This should be done by the CSS parser!
|
|
CSS::ValueID text_align = CSS::ValueID::Left;
|
|
auto text_align_string = style().string_or_fallback(CSS::PropertyID::TextAlign, "left");
|
|
if (text_align_string == "center")
|
|
text_align = CSS::ValueID::Center;
|
|
else if (text_align_string == "left")
|
|
text_align = CSS::ValueID::Left;
|
|
else if (text_align_string == "right")
|
|
text_align = CSS::ValueID::Right;
|
|
else if (text_align_string == "justify")
|
|
text_align = CSS::ValueID::Justify;
|
|
|
|
for (auto& line_box : m_line_boxes) {
|
|
int max_height = min_line_height;
|
|
for (auto& fragment : line_box.fragments()) {
|
|
max_height = max(max_height, enclosing_int_rect(fragment.rect()).height());
|
|
}
|
|
|
|
int x_offset = x();
|
|
int excess_horizontal_space = width() - line_box.width();
|
|
|
|
switch (text_align) {
|
|
case CSS::ValueID::Center:
|
|
x_offset += excess_horizontal_space / 2;
|
|
break;
|
|
case CSS::ValueID::Right:
|
|
x_offset += excess_horizontal_space;
|
|
break;
|
|
case CSS::ValueID::Left:
|
|
case CSS::ValueID::Justify:
|
|
default:
|
|
break;
|
|
}
|
|
|
|
int excess_horizontal_space_including_whitespace = excess_horizontal_space;
|
|
int whitespace_count = 0;
|
|
if (text_align == CSS::ValueID::Justify) {
|
|
for (auto& fragment : line_box.fragments()) {
|
|
if (fragment.is_justifiable_whitespace()) {
|
|
++whitespace_count;
|
|
excess_horizontal_space_including_whitespace += fragment.rect().width();
|
|
}
|
|
}
|
|
}
|
|
|
|
float justified_space_width = whitespace_count ? ((float)excess_horizontal_space_including_whitespace / (float)whitespace_count) : 0;
|
|
|
|
for (int i = 0; i < line_box.fragments().size(); ++i) {
|
|
auto& fragment = line_box.fragments()[i];
|
|
// Vertically align everyone's bottom to the line.
|
|
// FIXME: Support other kinds of vertical alignment.
|
|
fragment.rect().set_x(x_offset + fragment.rect().x());
|
|
fragment.rect().set_y(y() + content_height + (max_height - fragment.rect().height()));
|
|
|
|
if (text_align == CSS::ValueID::Justify) {
|
|
if (fragment.is_justifiable_whitespace()) {
|
|
if (fragment.rect().width() != justified_space_width) {
|
|
float diff = justified_space_width - fragment.rect().width();
|
|
fragment.rect().set_width(justified_space_width);
|
|
// Shift subsequent sibling fragments to the right to adjust for change in width.
|
|
for (int j = i + 1; j < line_box.fragments().size(); ++j) {
|
|
line_box.fragments()[j].rect().move_by(diff, 0);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (is<LayoutReplaced>(fragment.layout_node()))
|
|
const_cast<LayoutReplaced&>(to<LayoutReplaced>(fragment.layout_node())).set_rect(enclosing_int_rect(fragment.rect()));
|
|
}
|
|
|
|
content_height += max_height;
|
|
}
|
|
|
|
rect().set_height(content_height);
|
|
}
|
|
|
|
void LayoutBlock::compute_width()
|
|
{
|
|
auto& style = this->style();
|
|
|
|
auto auto_value = Length();
|
|
auto zero_value = Length(0, Length::Type::Absolute);
|
|
auto width = style.length_or_fallback(CSS::PropertyID::Width, auto_value);
|
|
auto margin_left = style.length_or_fallback(CSS::PropertyID::MarginLeft, zero_value);
|
|
auto margin_right = style.length_or_fallback(CSS::PropertyID::MarginRight, zero_value);
|
|
auto border_left = style.length_or_fallback(CSS::PropertyID::BorderLeftWidth, zero_value);
|
|
auto border_right = style.length_or_fallback(CSS::PropertyID::BorderRightWidth, zero_value);
|
|
auto padding_left = style.length_or_fallback(CSS::PropertyID::PaddingLeft, zero_value);
|
|
auto padding_right = style.length_or_fallback(CSS::PropertyID::PaddingRight, zero_value);
|
|
|
|
#ifdef HTML_DEBUG
|
|
dbg() << " Left: " << margin_left << "+" << border_left << "+" << padding_left;
|
|
dbg() << "Right: " << margin_right << "+" << border_right << "+" << padding_right;
|
|
#endif
|
|
|
|
int total_px = 0;
|
|
for (auto& value : { margin_left, border_left, padding_left, width, padding_right, border_right, margin_right }) {
|
|
total_px += value.to_px();
|
|
}
|
|
|
|
#ifdef HTML_DEBUG
|
|
dbg() << "Total: " << total_px;
|
|
#endif
|
|
|
|
// 10.3.3 Block-level, non-replaced elements in normal flow
|
|
// If 'width' is not 'auto' and 'border-left-width' + 'padding-left' + 'width' + 'padding-right' + 'border-right-width' (plus any of 'margin-left' or 'margin-right' that are not 'auto') is larger than the width of the containing block, then any 'auto' values for 'margin-left' or 'margin-right' are, for the following rules, treated as zero.
|
|
if (width.is_auto() && total_px > containing_block()->width()) {
|
|
if (margin_left.is_auto())
|
|
margin_left = zero_value;
|
|
if (margin_right.is_auto())
|
|
margin_right = zero_value;
|
|
}
|
|
|
|
// 10.3.3 cont'd.
|
|
auto underflow_px = containing_block()->width() - total_px;
|
|
|
|
if (width.is_auto()) {
|
|
if (margin_left.is_auto())
|
|
margin_left = zero_value;
|
|
if (margin_right.is_auto())
|
|
margin_right = zero_value;
|
|
if (underflow_px >= 0) {
|
|
width = Length(underflow_px, Length::Type::Absolute);
|
|
} else {
|
|
width = zero_value;
|
|
margin_right = Length(margin_right.to_px() + underflow_px, Length::Type::Absolute);
|
|
}
|
|
} else {
|
|
if (!margin_left.is_auto() && !margin_right.is_auto()) {
|
|
margin_right = Length(margin_right.to_px() + underflow_px, Length::Type::Absolute);
|
|
} else if (!margin_left.is_auto() && margin_right.is_auto()) {
|
|
margin_right = Length(underflow_px, Length::Type::Absolute);
|
|
} else if (margin_left.is_auto() && !margin_right.is_auto()) {
|
|
margin_left = Length(underflow_px, Length::Type::Absolute);
|
|
} else { // margin_left.is_auto() && margin_right.is_auto()
|
|
auto half_of_the_underflow = Length(underflow_px / 2, Length::Type::Absolute);
|
|
margin_left = half_of_the_underflow;
|
|
margin_right = half_of_the_underflow;
|
|
}
|
|
}
|
|
|
|
rect().set_width(width.to_px());
|
|
box_model().margin().left = margin_left;
|
|
box_model().margin().right = margin_right;
|
|
box_model().border().left = border_left;
|
|
box_model().border().right = border_right;
|
|
box_model().padding().left = padding_left;
|
|
box_model().padding().right = padding_right;
|
|
}
|
|
|
|
void LayoutBlock::compute_position()
|
|
{
|
|
auto& style = this->style();
|
|
|
|
auto auto_value = Length();
|
|
auto zero_value = Length(0, Length::Type::Absolute);
|
|
|
|
auto width = style.length_or_fallback(CSS::PropertyID::Width, auto_value);
|
|
|
|
box_model().margin().top = style.length_or_fallback(CSS::PropertyID::MarginTop, zero_value);
|
|
box_model().margin().bottom = style.length_or_fallback(CSS::PropertyID::MarginBottom, zero_value);
|
|
box_model().border().top = style.length_or_fallback(CSS::PropertyID::BorderTopWidth, zero_value);
|
|
box_model().border().bottom = style.length_or_fallback(CSS::PropertyID::BorderBottomWidth, zero_value);
|
|
box_model().padding().top = style.length_or_fallback(CSS::PropertyID::PaddingTop, zero_value);
|
|
box_model().padding().bottom = style.length_or_fallback(CSS::PropertyID::PaddingBottom, zero_value);
|
|
rect().set_x(containing_block()->x() + box_model().margin().left.to_px() + box_model().border().left.to_px() + box_model().padding().left.to_px());
|
|
|
|
int top_border = -1;
|
|
if (previous_sibling() != nullptr) {
|
|
auto& previous_sibling_rect = previous_sibling()->rect();
|
|
auto& previous_sibling_style = previous_sibling()->box_model();
|
|
top_border = previous_sibling_rect.y() + previous_sibling_rect.height();
|
|
top_border += previous_sibling_style.full_margin().bottom;
|
|
} else {
|
|
top_border = containing_block()->y();
|
|
}
|
|
rect().set_y(top_border + box_model().full_margin().top);
|
|
}
|
|
|
|
void LayoutBlock::compute_height()
|
|
{
|
|
auto& style = this->style();
|
|
|
|
auto height_property = style.property(CSS::PropertyID::Height);
|
|
if (!height_property.has_value())
|
|
return;
|
|
auto height_length = height_property.value()->to_length();
|
|
if (height_length.is_absolute())
|
|
rect().set_height(height_length.to_px());
|
|
}
|
|
|
|
void LayoutBlock::render(RenderingContext& context)
|
|
{
|
|
if (!is_visible())
|
|
return;
|
|
|
|
LayoutBox::render(context);
|
|
|
|
if (children_are_inline()) {
|
|
for (auto& line_box : m_line_boxes) {
|
|
for (auto& fragment : line_box.fragments()) {
|
|
if (context.should_show_line_box_borders())
|
|
context.painter().draw_rect(enclosing_int_rect(fragment.rect()), Color::Green);
|
|
fragment.render(context);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
HitTestResult LayoutBlock::hit_test(const Point& position) const
|
|
{
|
|
if (!children_are_inline())
|
|
return LayoutBox::hit_test(position);
|
|
|
|
HitTestResult result;
|
|
for (auto& line_box : m_line_boxes) {
|
|
for (auto& fragment : line_box.fragments()) {
|
|
if (enclosing_int_rect(fragment.rect()).contains(position)) {
|
|
return { fragment.layout_node() };
|
|
}
|
|
}
|
|
}
|
|
return {};
|
|
}
|
|
|
|
NonnullRefPtr<StyleProperties> LayoutBlock::style_for_anonymous_block() const
|
|
{
|
|
auto new_style = StyleProperties::create();
|
|
|
|
style().for_each_property([&](auto property_id, auto& value) {
|
|
if (StyleResolver::is_inherited_property(property_id))
|
|
new_style->set_property(property_id, value);
|
|
});
|
|
|
|
return new_style;
|
|
}
|
|
|
|
LineBox& LayoutBlock::ensure_last_line_box()
|
|
{
|
|
if (m_line_boxes.is_empty())
|
|
m_line_boxes.append(LineBox());
|
|
return m_line_boxes.last();
|
|
}
|
|
|
|
LineBox& LayoutBlock::add_line_box()
|
|
{
|
|
m_line_boxes.append(LineBox());
|
|
return m_line_boxes.last();
|
|
}
|