lightningcss/values/
resolution.rs

1//! CSS resolution values.
2
3use super::length::serialize_dimension;
4use super::number::CSSNumber;
5use crate::compat::Feature;
6use crate::error::{ParserError, PrinterError};
7use crate::printer::Printer;
8use crate::traits::{Parse, ToCss};
9#[cfg(feature = "visitor")]
10use crate::visitor::Visit;
11use cssparser::*;
12
13/// A CSS [`<resolution>`](https://www.w3.org/TR/css-values-4/#resolution) value.
14#[derive(Debug, Clone, PartialEq)]
15#[cfg_attr(feature = "visitor", derive(Visit))]
16#[cfg_attr(feature = "visitor", visit(visit_resolution, RESOLUTIONS))]
17#[cfg_attr(
18  feature = "serde",
19  derive(serde::Serialize, serde::Deserialize),
20  serde(tag = "type", content = "value", rename_all = "kebab-case")
21)]
22#[cfg_attr(feature = "jsonschema", derive(schemars::JsonSchema))]
23#[cfg_attr(feature = "into_owned", derive(static_self::IntoOwned))]
24pub enum Resolution {
25  /// A resolution in dots per inch.
26  Dpi(CSSNumber),
27  /// A resolution in dots per centimeter.
28  Dpcm(CSSNumber),
29  /// A resolution in dots per px.
30  Dppx(CSSNumber),
31}
32
33impl<'i> Parse<'i> for Resolution {
34  fn parse<'t>(input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i, ParserError<'i>>> {
35    // TODO: calc?
36    let location = input.current_source_location();
37    match *input.next()? {
38      Token::Dimension { value, ref unit, .. } => {
39        match_ignore_ascii_case! { unit,
40          "dpi" => Ok(Resolution::Dpi(value)),
41          "dpcm" => Ok(Resolution::Dpcm(value)),
42          "dppx" | "x" => Ok(Resolution::Dppx(value)),
43          _ => Err(location.new_unexpected_token_error(Token::Ident(unit.clone())))
44        }
45      }
46      ref t => Err(location.new_unexpected_token_error(t.clone())),
47    }
48  }
49}
50
51impl<'i> TryFrom<&Token<'i>> for Resolution {
52  type Error = ();
53
54  fn try_from(token: &Token) -> Result<Self, Self::Error> {
55    match token {
56      Token::Dimension { value, ref unit, .. } => match_ignore_ascii_case! { unit,
57        "dpi" => Ok(Resolution::Dpi(*value)),
58        "dpcm" => Ok(Resolution::Dpcm(*value)),
59        "dppx" | "x" => Ok(Resolution::Dppx(*value)),
60        _ => Err(()),
61      },
62      _ => Err(()),
63    }
64  }
65}
66
67impl ToCss for Resolution {
68  fn to_css<W>(&self, dest: &mut Printer<W>) -> Result<(), PrinterError>
69  where
70    W: std::fmt::Write,
71  {
72    let (value, unit) = match self {
73      Resolution::Dpi(dpi) => (*dpi, "dpi"),
74      Resolution::Dpcm(dpcm) => (*dpcm, "dpcm"),
75      Resolution::Dppx(dppx) => {
76        if dest.targets.is_compatible(Feature::XResolutionUnit) {
77          (*dppx, "x")
78        } else {
79          (*dppx, "dppx")
80        }
81      }
82    };
83
84    serialize_dimension(value, unit, dest)
85  }
86}
87
88impl std::ops::Add<CSSNumber> for Resolution {
89  type Output = Self;
90
91  fn add(self, other: CSSNumber) -> Resolution {
92    match self {
93      Resolution::Dpi(dpi) => Resolution::Dpi(dpi + other),
94      Resolution::Dpcm(dpcm) => Resolution::Dpcm(dpcm + other),
95      Resolution::Dppx(dppx) => Resolution::Dppx(dppx + other),
96    }
97  }
98}
lightningcss/values/resolution.rs

lightningcss/values/
resolution.rs
