#[derive(Clone, Copy, PartialEq, Debug)]
pub struct Color {
pub r: f32,
pub g: f32,
pub b: f32,
pub a: f32,
}
fn map_err(r: Result<u8, std::num::ParseIntError>) -> Result<u8, String> {
r.map_err(|e| format!("Error parsing hex: {}", e))
}
impl Color {
pub fn gray(lightness: f32) -> Color {
Self {
r: lightness,
g: lightness,
b: lightness,
a: 1.0,
}
}
pub fn new(r: f32, g: f32, b: f32, a: f32) -> Self {
Self { r, g, b, a }
}
pub fn mix(&self, rhs: Color, s: f32) -> Color {
Color {
r: (1.0 - s) * self.r + s * rhs.r,
g: (1.0 - s) * self.g + s * rhs.g,
b: (1.0 - s) * self.b + s * rhs.b,
a: (1.0 - s) * self.a + s * rhs.a,
}
}
pub fn alpha(&self, a: f32) -> Self {
Self {
r: self.r,
g: self.g,
b: self.b,
a,
}
}
pub const CYAN: Color = Color {
r: 0.0,
g: 1.0,
b: 1.0,
a: 1.0,
};
pub const MAGENTA: Color = Color {
r: 1.0,
g: 0.0,
b: 1.0,
a: 1.0,
};
pub const WHITE: Color = Color {
r: 1.0,
g: 1.0,
b: 1.0,
a: 1.0,
};
pub fn hex(hex: &str) -> Result<Color, String> {
if hex.len() == 9 && hex.starts_with('#') {
Ok(Color {
r: map_err(u8::from_str_radix(&hex[1..3], 16))? as f32 / 255.0,
g: map_err(u8::from_str_radix(&hex[3..5], 16))? as f32 / 255.0,
b: map_err(u8::from_str_radix(&hex[5..7], 16))? as f32 / 255.0,
a: map_err(u8::from_str_radix(&hex[7..9], 16))? as f32 / 255.0,
})
} else if hex.len() == 7 && hex.starts_with('#') {
Ok(Color {
r: map_err(u8::from_str_radix(&hex[1..3], 16))? as f32 / 255.0,
g: map_err(u8::from_str_radix(&hex[3..5], 16))? as f32 / 255.0,
b: map_err(u8::from_str_radix(&hex[5..7], 16))? as f32 / 255.0,
a: 1.0,
})
} else {
Err("Error parsing hex. Example of valid formats: #FFFFFF or #ffffffff".to_string())
}
}
pub const fn hex_const(hex: &str) -> Color {
let lut = [
0.000000, 0.003922, 0.007843, 0.011765, 0.015686, 0.019608, 0.023529, 0.027451,
0.031373, 0.035294, 0.039216, 0.043137, 0.047059, 0.050980, 0.054902, 0.058824,
0.062745, 0.066667, 0.070588, 0.074510, 0.078431, 0.082353, 0.086275, 0.090196,
0.094118, 0.098039, 0.101961, 0.105882, 0.109804, 0.113725, 0.117647, 0.121569,
0.125490, 0.129412, 0.133333, 0.137255, 0.141176, 0.145098, 0.149020, 0.152941,
0.156863, 0.160784, 0.164706, 0.168627, 0.172549, 0.176471, 0.180392, 0.184314,
0.188235, 0.192157, 0.196078, 0.200000, 0.203922, 0.207843, 0.211765, 0.215686,
0.219608, 0.223529, 0.227451, 0.231373, 0.235294, 0.239216, 0.243137, 0.247059,
0.250980, 0.254902, 0.258824, 0.262745, 0.266667, 0.270588, 0.274510, 0.278431,
0.282353, 0.286275, 0.290196, 0.294118, 0.298039, 0.301961, 0.305882, 0.309804,
0.313725, 0.317647, 0.321569, 0.325490, 0.329412, 0.333333, 0.337255, 0.341176,
0.345098, 0.349020, 0.352941, 0.356863, 0.360784, 0.364706, 0.368627, 0.372549,
0.376471, 0.380392, 0.384314, 0.388235, 0.392157, 0.396078, 0.400000, 0.403922,
0.407843, 0.411765, 0.415686, 0.419608, 0.423529, 0.427451, 0.431373, 0.435294,
0.439216, 0.443137, 0.447059, 0.450980, 0.454902, 0.458824, 0.462745, 0.466667,
0.470588, 0.474510, 0.478431, 0.482353, 0.486275, 0.490196, 0.494118, 0.498039,
0.501961, 0.505882, 0.509804, 0.513725, 0.517647, 0.521569, 0.525490, 0.529412,
0.533333, 0.537255, 0.541176, 0.545098, 0.549020, 0.552941, 0.556863, 0.560784,
0.564706, 0.568627, 0.572549, 0.576471, 0.580392, 0.584314, 0.588235, 0.592157,
0.596078, 0.600000, 0.603922, 0.607843, 0.611765, 0.615686, 0.619608, 0.623529,
0.627451, 0.631373, 0.635294, 0.639216, 0.643137, 0.647059, 0.650980, 0.654902,
0.658824, 0.662745, 0.666667, 0.670588, 0.674510, 0.678431, 0.682353, 0.686275,
0.690196, 0.694118, 0.698039, 0.701961, 0.705882, 0.709804, 0.713725, 0.717647,
0.721569, 0.725490, 0.729412, 0.733333, 0.737255, 0.741176, 0.745098, 0.749020,
0.752941, 0.756863, 0.760784, 0.764706, 0.768627, 0.772549, 0.776471, 0.780392,
0.784314, 0.788235, 0.792157, 0.796078, 0.800000, 0.803922, 0.807843, 0.811765,
0.815686, 0.819608, 0.823529, 0.827451, 0.831373, 0.835294, 0.839216, 0.843137,
0.847059, 0.850980, 0.854902, 0.858824, 0.862745, 0.866667, 0.870588, 0.874510,
0.878431, 0.882353, 0.886275, 0.890196, 0.894118, 0.898039, 0.901961, 0.905882,
0.909804, 0.913725, 0.917647, 0.921569, 0.925490, 0.929412, 0.933333, 0.937255,
0.941176, 0.945098, 0.949020, 0.952941, 0.956863, 0.960784, 0.964706, 0.968627,
0.972549, 0.976471, 0.980392, 0.984314, 0.988235, 0.992157, 0.996078, 1.000000,
];
let bytes = hex.as_bytes();
Color {
r: lut[hex_digit(bytes[1]) * 16 + hex_digit(bytes[2])],
g: lut[hex_digit(bytes[3]) * 16 + hex_digit(bytes[4])],
b: lut[hex_digit(bytes[5]) * 16 + hex_digit(bytes[6])],
a: 1.0,
}
}
}
const fn hex_digit(x: u8) -> usize {
(if x >= b'0' && x <= b'9' {
x - b'0'
} else if x >= b'a' && x <= b'f' {
x - b'a' + 10
} else if x >= b'A' && x <= b'F' {
x - b'A' + 10
} else {
panic!("bad hex digit")
}) as usize
}