ladybird/Libraries/LibWeb/CSS/Resolution.cpp
Sam Atkins 338282f74d LibWeb/CSS: Treat x resolution unit separately from dppx
Tests show that we need to preserve whether x or dppx units were used,
so the simplest way is to treat them separately.
2025-05-17 07:53:24 +01:00

72 lines
1.7 KiB
C++

/*
* Copyright (c) 2022-2025, Sam Atkins <sam@ladybird.org>
* Copyright (c) 2024, Glenn Skrzypczak <glenn.skrzypczak@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/CSS/Resolution.h>
namespace Web::CSS {
Resolution::Resolution(double value, Type type)
: m_type(type)
, m_value(value)
{
}
Resolution Resolution::make_dots_per_pixel(double value)
{
return { value, Type::Dppx };
}
String Resolution::to_string(SerializationMode serialization_mode) const
{
if (serialization_mode == SerializationMode::ResolvedValue)
return MUST(String::formatted("{}dppx", to_dots_per_pixel()));
return MUST(String::formatted("{}{}", raw_value(), unit_name()));
}
double Resolution::to_dots_per_pixel() const
{
switch (m_type) {
case Type::Dpi:
return m_value / 96; // 1in = 2.54cm = 96px
case Type::Dpcm:
return m_value / (96.0 / 2.54); // 1cm = 96px/2.54
case Type::Dppx:
case Type::X:
return m_value;
}
VERIFY_NOT_REACHED();
}
StringView Resolution::unit_name() const
{
switch (m_type) {
case Type::Dpi:
return "dpi"sv;
case Type::Dpcm:
return "dpcm"sv;
case Type::Dppx:
return "dppx"sv;
case Type::X:
return "x"sv;
}
VERIFY_NOT_REACHED();
}
Optional<Resolution::Type> Resolution::unit_from_name(StringView name)
{
if (name.equals_ignoring_ascii_case("dpi"sv))
return Type::Dpi;
if (name.equals_ignoring_ascii_case("dpcm"sv))
return Type::Dpcm;
if (name.equals_ignoring_ascii_case("dppx"sv))
return Type::Dppx;
if (name.equals_ignoring_ascii_case("x"sv))
return Type::X;
return {};
}
}