diff options
| -rw-r--r-- | core/src/color.rs | 127 |
1 files changed, 112 insertions, 15 deletions
diff --git a/core/src/color.rs b/core/src/color.rs index 4e79defb..46fe9ecd 100644 --- a/core/src/color.rs +++ b/core/src/color.rs @@ -108,6 +108,53 @@ impl Color { } } + /// Parses a [`Color`] from a hex string. + /// + /// Supported formats are `#rrggbb`, `#rrggbbaa`, `#rgb`, and `#rgba`. + /// The starting "#" is optional. Both uppercase and lowercase are supported. + /// + /// If you have a static color string, using the [`color!`] macro should be preferred + /// since it leverages hexadecimal literal notation and arithmetic directly. + /// + /// [`color!`]: crate::color! + pub fn parse(s: &str) -> Option<Color> { + let hex = s.strip_prefix('#').unwrap_or(s); + + let parse_channel = |from: usize, to: usize| { + let num = + usize::from_str_radix(&hex[from..=to], 16).ok()? as f32 / 255.0; + + // If we only got half a byte (one letter), expand it into a full byte (two letters) + Some(if from == to { num + num * 16.0 } else { num }) + }; + + Some(match hex.len() { + 3 => Color::from_rgb( + parse_channel(0, 0)?, + parse_channel(1, 1)?, + parse_channel(2, 2)?, + ), + 4 => Color::from_rgba( + parse_channel(0, 0)?, + parse_channel(1, 1)?, + parse_channel(2, 2)?, + parse_channel(3, 3)?, + ), + 6 => Color::from_rgb( + parse_channel(0, 1)?, + parse_channel(2, 3)?, + parse_channel(4, 5)?, + ), + 8 => Color::from_rgba( + parse_channel(0, 1)?, + parse_channel(2, 3)?, + parse_channel(4, 5)?, + parse_channel(6, 7)?, + ), + _ => None?, + }) + } + /// Converts the [`Color`] into its RGBA8 equivalent. #[must_use] pub fn into_rgba8(self) -> [u8; 4] { @@ -178,34 +225,65 @@ impl From<[f32; 4]> for Color { /// /// ``` /// # use iced_core::{Color, color}; -/// assert_eq!(color!(0, 0, 0), Color::from_rgb(0., 0., 0.)); -/// assert_eq!(color!(0, 0, 0, 0.), Color::from_rgba(0., 0., 0., 0.)); -/// assert_eq!(color!(0xffffff), Color::from_rgb(1., 1., 1.)); -/// assert_eq!(color!(0xffffff, 0.), Color::from_rgba(1., 1., 1., 0.)); +/// assert_eq!(color!(0, 0, 0), Color::BLACK); +/// assert_eq!(color!(0, 0, 0, 0.0), Color::TRANSPARENT); +/// assert_eq!(color!(0xffffff), Color::from_rgb(1.0, 1.0, 1.0)); +/// assert_eq!(color!(0xffffff, 0.), Color::from_rgba(1.0, 1.0, 1.0, 0.0)); +/// assert_eq!(color!(0x123), Color::from_rgba8(0x11, 0x22, 0x33, 1.0)); +/// assert_eq!(color!(0x123), color!(0x112233)); /// ``` #[macro_export] macro_rules! color { ($r:expr, $g:expr, $b:expr) => { color!($r, $g, $b, 1.0) }; - ($r:expr, $g:expr, $b:expr, $a:expr) => { - $crate::Color { - r: $r as f32 / 255.0, - g: $g as f32 / 255.0, - b: $b as f32 / 255.0, - a: $a, + ($r:expr, $g:expr, $b:expr, $a:expr) => {{ + let r = $r as f32 / 255.0; + let g = $g as f32 / 255.0; + let b = $b as f32 / 255.0; + + #[allow(clippy::manual_range_contains)] + { + debug_assert!( + r >= 0.0 && r <= 1.0, + "R channel must be in [0, 255] range." + ); + debug_assert!( + g >= 0.0 && g <= 1.0, + "G channel must be in [0, 255] range." + ); + debug_assert!( + b >= 0.0 && b <= 1.0, + "B channel must be in [0, 255] range." + ); } - }; + + $crate::Color { r, g, b, a: $a } + }}; ($hex:expr) => {{ color!($hex, 1.0) }}; ($hex:expr, $a:expr) => {{ let hex = $hex as u32; - let r = (hex & 0xff0000) >> 16; - let g = (hex & 0xff00) >> 8; - let b = (hex & 0xff); - color!(r, g, b, $a) + if hex <= 0xfff { + let r = (hex & 0xf00) >> 8; + let g = (hex & 0x0f0) >> 4; + let b = (hex & 0x00f); + + color!((r << 4 | r), (g << 4 | g), (b << 4 | b), $a) + } else { + debug_assert!( + hex <= 0xffffff, + "color! value must not exceed 0xffffff" + ); + + let r = (hex & 0xff0000) >> 16; + let g = (hex & 0xff00) >> 8; + let b = (hex & 0xff); + + color!(r, g, b, $a) + } }}; } @@ -273,4 +351,23 @@ mod tests { assert_relative_eq!(result.b, 0.3); assert_relative_eq!(result.a, 1.0); } + + #[test] + fn parse() { + let tests = [ + ("#ff0000", [255, 0, 0, 255]), + ("00ff0080", [0, 255, 0, 128]), + ("#F80", [255, 136, 0, 255]), + ("#00f1", [0, 0, 255, 17]), + ]; + + for (arg, expected) in tests { + assert_eq!( + Color::parse(arg).expect("color must parse").into_rgba8(), + expected + ); + } + + assert!(Color::parse("invalid").is_none()); + } } |