ladybird/Libraries/LibGfx/FontCascadeList.cpp
Andreas Kling a4fb21308d LibWeb: Don't add range data for FontCascadeList with no Unicode ranges
This fixes a bunch of WPT crashes in /html/canvas/offscreen/text/
2025-07-15 10:06:10 +02:00

70 lines
1.9 KiB
C++

/*
* Copyright (c) 2023, Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibGfx/FontCascadeList.h>
namespace Gfx {
void FontCascadeList::add(NonnullRefPtr<Font const> font)
{
m_fonts.append({ move(font), {} });
}
void FontCascadeList::add(NonnullRefPtr<Font const> font, Vector<UnicodeRange> unicode_ranges)
{
if (unicode_ranges.is_empty()) {
m_fonts.append({ move(font), {} });
return;
}
u32 lowest_code_point = 0xFFFFFFFF;
u32 highest_code_point = 0;
for (auto& range : unicode_ranges) {
lowest_code_point = min(lowest_code_point, range.min_code_point());
highest_code_point = max(highest_code_point, range.max_code_point());
}
m_fonts.append({ move(font),
Entry::RangeData {
{ lowest_code_point, highest_code_point },
move(unicode_ranges),
} });
}
void FontCascadeList::extend(FontCascadeList const& other)
{
m_fonts.extend(other.m_fonts);
}
Gfx::Font const& FontCascadeList::font_for_code_point(u32 code_point) const
{
for (auto const& entry : m_fonts) {
if (entry.range_data.has_value()) {
if (!entry.range_data->enclosing_range.contains(code_point))
continue;
for (auto const& range : entry.range_data->unicode_ranges) {
if (range.contains(code_point) && entry.font->contains_glyph(code_point))
return entry.font;
}
} else if (entry.font->contains_glyph(code_point)) {
return entry.font;
}
}
return *m_last_resort_font;
}
bool FontCascadeList::equals(FontCascadeList const& other) const
{
if (m_fonts.size() != other.m_fonts.size())
return false;
for (size_t i = 0; i < m_fonts.size(); ++i) {
if (m_fonts[i].font != other.m_fonts[i].font)
return false;
}
return true;
}
}