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// Allow approx_constant because these values are raw color data, not mathematical constants.
#![allow(clippy::approx_constant)]
use crate::Precision;
use csscolorparser::Color;
// Continuous color mapping schemes (colormaps) for numerical data visualization.
// The color was got from https://hauselin.github.io/colorpalettejs/ and
// https://docs.rs/colorous/latest/colorous/index.html
/// Continuous color mapping schemes (colormaps) for numerical data visualization.
/// Optimized for direct SingleColor (f64) output to support high-performance rendering.
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum ColorMap {
// Perceptually Uniform (Best for accurate data representation)
Viridis,
Inferno,
Magma,
Plasma,
Cividis,
// Sequential Single Hue
Blues,
Greens,
Greys,
Oranges,
Purples,
Reds,
// Sequential Multi-Hue
BuGn, // Blue-Green
BuPu, // Blue-Purple
GnBu, // Green-Blue
OrRd, // Orange-Red
PuBuGn, // Purple-Blue-Green
PuBu, // Purple-Blue
PuRd, // Purple-Red
RdPu, // Red-Purple
YlGnBu, // Yellow-Green-Blue
YlGn, // Yellow-Green
YlOrBr, // Yellow-Orange-Brown
YlOrRd, // Yellow-Orange-Red
// Specialized / Legacy
Rainbow,
Jet,
Hot,
Cool,
}
impl ColorMap {
/// Returns a SingleColor based on a normalized value between 0.0 and 1.0.
/// Following standard convention, the alpha channel is set to 1.0 (opaque).
pub(crate) fn get_color(&self, value: f64) -> SingleColor {
let t = value.clamp(0.0, 1.0);
match self {
ColorMap::Viridis => Self::interpolate_stops(
&[
(0.000, 0.267, 0.004, 0.329), // #440154
(0.067, 0.282, 0.102, 0.424), // #481a6c
(0.133, 0.278, 0.184, 0.490), // #472f7d
(0.200, 0.255, 0.267, 0.529), // #414487
(0.267, 0.224, 0.337, 0.549), // #39568c
(0.333, 0.192, 0.408, 0.557), // #31688e
(0.400, 0.165, 0.471, 0.557), // #2a788e
(0.467, 0.137, 0.533, 0.557), // #23888e
(0.533, 0.122, 0.596, 0.545), // #1f988b
(0.600, 0.133, 0.659, 0.518), // #22a884
(0.667, 0.208, 0.718, 0.475), // #35b779
(0.733, 0.329, 0.773, 0.408), // #54c568
(0.800, 0.478, 0.820, 0.318), // #7ad151
(0.867, 0.647, 0.859, 0.212), // #a5db36
(0.933, 0.824, 0.886, 0.106), // #d2e21b
(1.000, 0.992, 0.906, 0.145), // #fde725
],
t,
),
ColorMap::Inferno => Self::interpolate_stops(
&[
(0.000, 0.000, 0.000, 0.016), // #000004
(0.067, 0.047, 0.031, 0.149), // #0c0826
(0.133, 0.141, 0.047, 0.310), // #240c4f
(0.200, 0.259, 0.039, 0.408), // #420a68
(0.267, 0.365, 0.071, 0.431), // #5d126e
(0.333, 0.471, 0.110, 0.427), // #781c6d
(0.400, 0.576, 0.149, 0.404), // #932667
(0.467, 0.682, 0.188, 0.361), // #ae305c
(0.533, 0.780, 0.243, 0.298), // #c73e4c
(0.600, 0.867, 0.318, 0.227), // #dd513a
(0.667, 0.929, 0.412, 0.145), // #ed6925
(0.733, 0.973, 0.522, 0.059), // #f8850f
(0.800, 0.988, 0.647, 0.039), // #fca50a
(0.867, 0.980, 0.776, 0.176), // #fac62d
(0.933, 0.949, 0.902, 0.380), // #f2e661
(1.000, 0.988, 1.000, 0.643), // #fcffa4
],
t,
),
ColorMap::Magma => Self::interpolate_stops(
&[
(0.000, 0.000, 0.000, 0.016), // #000004
(0.067, 0.043, 0.035, 0.141), // #0b0924
(0.133, 0.125, 0.067, 0.294), // #20114b
(0.200, 0.231, 0.059, 0.439), // #3b0f70
(0.267, 0.341, 0.082, 0.494), // #57157e
(0.333, 0.447, 0.122, 0.506), // #721f81
(0.400, 0.549, 0.161, 0.506), // #8c2981
(0.467, 0.659, 0.196, 0.490), // #a8327d
(0.533, 0.769, 0.235, 0.459), // #c43c75
(0.600, 0.871, 0.286, 0.408), // #de4968
(0.667, 0.945, 0.376, 0.365), // #f1605d
(0.733, 0.980, 0.498, 0.369), // #fa7f5e
(0.800, 0.996, 0.624, 0.427), // #fe9f6d
(0.867, 0.996, 0.749, 0.518), // #febf84
(0.933, 0.992, 0.871, 0.627), // #fddea0
(1.000, 0.988, 0.992, 0.749), // #fcfdbf
],
t,
),
ColorMap::Plasma => Self::interpolate_stops(
&[
(0.000, 0.051, 0.031, 0.529), // #0d0887
(0.067, 0.200, 0.020, 0.592), // #330597
(0.133, 0.314, 0.008, 0.635), // #5002a2
(0.200, 0.416, 0.000, 0.659), // #6a00a8
(0.267, 0.518, 0.020, 0.655), // #8405a7
(0.333, 0.612, 0.090, 0.620), // #9c179e
(0.400, 0.694, 0.165, 0.565), // #b12a90
(0.467, 0.765, 0.239, 0.502), // #c33d80
(0.533, 0.827, 0.318, 0.443), // #d35171
(0.600, 0.882, 0.392, 0.384), // #e16462
(0.667, 0.929, 0.475, 0.325), // #ed7953
(0.733, 0.965, 0.561, 0.267), // #f68f44
(0.800, 0.988, 0.651, 0.212), // #fca636
(0.867, 0.996, 0.753, 0.161), // #fec029
(0.933, 0.976, 0.863, 0.141), // #f9dc24
(1.000, 0.941, 0.976, 0.129), // #f0f921
],
t,
),
ColorMap::Cividis => Self::interpolate_stops(
&[
(0.000, 0.000, 0.125, 0.318), // #002051
(0.067, 0.008, 0.173, 0.396), // #022c65
(0.133, 0.078, 0.220, 0.427), // #14386d
(0.200, 0.169, 0.267, 0.431), // #2b446e
(0.267, 0.259, 0.314, 0.431), // #42506e
(0.333, 0.341, 0.361, 0.431), // #575c6e
(0.400, 0.412, 0.412, 0.439), // #696970
(0.467, 0.471, 0.459, 0.451), // #787573
(0.533, 0.525, 0.510, 0.463), // #868276
(0.600, 0.580, 0.561, 0.471), // #948f78
(0.667, 0.643, 0.616, 0.471), // #a49d78
(0.733, 0.714, 0.671, 0.443), // #b6ab73
(0.800, 0.792, 0.729, 0.416), // #caba6a
(0.867, 0.878, 0.788, 0.365), // #e0c95d
(0.933, 0.949, 0.851, 0.314), // #f2d950
(1.000, 0.992, 0.918, 0.271), // #fdea45
],
t,
),
// --- Sequential ---
ColorMap::Blues => Self::interpolate_stops(
&[
(0.000, 0.969, 0.984, 1.000), // #f7fbff
(0.125, 0.871, 0.922, 0.969), // #deebf7
(0.250, 0.776, 0.859, 0.937), // #c6dbef
(0.375, 0.620, 0.792, 0.882), // #9ecae1
(0.500, 0.420, 0.682, 0.839), // #6baed6
(0.625, 0.259, 0.573, 0.776), // #4292c6
(0.750, 0.129, 0.443, 0.710), // #2171b5
(0.875, 0.031, 0.318, 0.612), // #08519c
(1.000, 0.031, 0.188, 0.420), // #08306b
],
t,
),
ColorMap::Greens => Self::interpolate_stops(
&[
(0.000, 0.969, 0.988, 0.961), // #f7fcf5
(0.125, 0.898, 0.961, 0.878), // #e5f5e0
(0.250, 0.780, 0.914, 0.753), // #c7e9c0
(0.375, 0.631, 0.851, 0.608), // #a1d99b
(0.500, 0.455, 0.769, 0.463), // #74c476
(0.625, 0.255, 0.671, 0.365), // #41ab5d
(0.750, 0.137, 0.545, 0.271), // #238b45
(0.875, 0.000, 0.427, 0.173), // #006d2c
(1.000, 0.000, 0.267, 0.106), // #00441b
],
t,
),
ColorMap::Greys => Self::interpolate_stops(
&[
(0.000, 1.000, 1.000, 1.000), // #ffffff
(0.125, 0.941, 0.941, 0.941), // #f0f0f0
(0.250, 0.851, 0.851, 0.851), // #d9d9d9
(0.375, 0.741, 0.741, 0.741), // #bdbdbd
(0.500, 0.588, 0.588, 0.588), // #969696
(0.625, 0.451, 0.451, 0.451), // #737373
(0.750, 0.322, 0.322, 0.322), // #525252
(0.875, 0.145, 0.145, 0.145), // #252525
(1.000, 0.000, 0.000, 0.000), // #000000
],
t,
),
ColorMap::Oranges => Self::interpolate_stops(
&[
(0.000, 1.000, 0.961, 0.922), // #fff5eb
(0.125, 0.996, 0.902, 0.808), // #fee6ce
(0.250, 0.992, 0.816, 0.635), // #fdd0a2
(0.375, 0.992, 0.682, 0.420), // #fdae6b
(0.500, 0.992, 0.553, 0.235), // #fd8d3c
(0.625, 0.945, 0.412, 0.075), // #f16913
(0.750, 0.851, 0.282, 0.004), // #d94801
(0.875, 0.651, 0.212, 0.012), // #a63603
(1.000, 0.498, 0.153, 0.016), // #7f2704
],
t,
),
ColorMap::Purples => Self::interpolate_stops(
&[
(0.000, 0.988, 0.984, 0.992), // #fcfbfd
(0.125, 0.937, 0.929, 0.961), // #efedf5
(0.250, 0.855, 0.855, 0.922), // #dadaeb
(0.375, 0.737, 0.741, 0.863), // #bcbddc
(0.500, 0.620, 0.604, 0.784), // #9e9ac8
(0.625, 0.502, 0.490, 0.729), // #807dba
(0.750, 0.416, 0.318, 0.639), // #6a51a3
(0.875, 0.329, 0.153, 0.561), // #54278f
(1.000, 0.247, 0.000, 0.490), // #3f007d
],
t,
),
ColorMap::Reds => Self::interpolate_stops(
&[
(0.000, 1.000, 0.961, 0.941), // #fff5f0
(0.125, 0.996, 0.878, 0.824), // #fee0d2
(0.250, 0.988, 0.733, 0.631), // #fcbba1
(0.375, 0.988, 0.573, 0.447), // #fc9272
(0.500, 0.984, 0.416, 0.290), // #fb6a4a
(0.625, 0.937, 0.231, 0.173), // #ef3b2c
(0.750, 0.796, 0.094, 0.114), // #cb181d
(0.875, 0.647, 0.059, 0.082), // #a50f15
(1.000, 0.404, 0.000, 0.051), // #67000d
],
t,
),
// --- Multi-hue Sequential ---
ColorMap::BuGn => Self::interpolate_stops(
&[
(0.000, 0.969, 0.988, 0.992), // #f7fcfd
(0.125, 0.898, 0.961, 0.976), // #e5f5f9
(0.250, 0.800, 0.925, 0.902), // #ccece6
(0.375, 0.600, 0.847, 0.788), // #99d8c9
(0.500, 0.400, 0.761, 0.643), // #66c2a4
(0.625, 0.255, 0.682, 0.463), // #41ae76
(0.750, 0.137, 0.545, 0.271), // #238b45
(0.875, 0.000, 0.427, 0.173), // #006d2c
(1.000, 0.000, 0.267, 0.106), // #00441b
],
t,
),
ColorMap::BuPu => Self::interpolate_stops(
&[
(0.000, 0.969, 0.988, 0.992), // #f7fcfd
(0.125, 0.878, 0.925, 0.957), // #e0ecf4
(0.250, 0.749, 0.827, 0.902), // #bfd3e6
(0.375, 0.620, 0.737, 0.855), // #9ebcda
(0.500, 0.549, 0.588, 0.776), // #8c96c6
(0.625, 0.549, 0.420, 0.694), // #8c6bb1
(0.750, 0.533, 0.255, 0.616), // #88419d
(0.875, 0.506, 0.059, 0.486), // #810f7c
(1.000, 0.302, 0.000, 0.294), // #4d004b
],
t,
),
ColorMap::GnBu => Self::interpolate_stops(
&[
(0.000, 0.969, 0.988, 0.941), // #f7fcf0
(0.125, 0.878, 0.953, 0.859), // #e0f3db
(0.250, 0.800, 0.922, 0.773), // #ccebc5
(0.375, 0.659, 0.867, 0.710), // #a8ddb5
(0.500, 0.482, 0.800, 0.769), // #7bccc4
(0.625, 0.306, 0.702, 0.827), // #4eb3d3
(0.750, 0.169, 0.549, 0.745), // #2b8cbe
(0.875, 0.031, 0.408, 0.675), // #0868ac
(1.000, 0.031, 0.251, 0.506), // #084081
],
t,
),
ColorMap::OrRd => Self::interpolate_stops(
&[
(0.000, 1.000, 0.969, 0.925), // #fff7ec
(0.125, 0.996, 0.910, 0.784), // #fee8c8
(0.250, 0.992, 0.831, 0.620), // #fdd49e
(0.375, 0.992, 0.733, 0.518), // #fdbb84
(0.500, 0.988, 0.553, 0.349), // #fc8d59
(0.625, 0.937, 0.396, 0.282), // #ef6548
(0.750, 0.843, 0.188, 0.122), // #d7301f
(0.875, 0.702, 0.000, 0.000), // #b30000
(1.000, 0.498, 0.000, 0.000), // #7f0000
],
t,
),
ColorMap::PuBuGn => Self::interpolate_stops(
&[
(0.000, 1.000, 0.969, 0.984), // #fff7fb
(0.125, 0.925, 0.886, 0.941), // #ece2f0
(0.250, 0.816, 0.820, 0.902), // #d0d1e6
(0.375, 0.651, 0.741, 0.859), // #a6bddb
(0.500, 0.404, 0.663, 0.812), // #67a9cf
(0.625, 0.212, 0.565, 0.753), // #3690c0
(0.750, 0.008, 0.506, 0.541), // #02818a
(0.875, 0.004, 0.424, 0.349), // #016c59
(1.000, 0.004, 0.275, 0.212), // #014636
],
t,
),
ColorMap::PuBu => Self::interpolate_stops(
&[
(0.000, 1.000, 0.969, 0.984), // #fff7fb
(0.125, 0.925, 0.906, 0.949), // #ece7f2
(0.250, 0.816, 0.820, 0.902), // #d0d1e6
(0.375, 0.651, 0.741, 0.859), // #a6bddb
(0.500, 0.455, 0.663, 0.812), // #74a9cf
(0.625, 0.212, 0.565, 0.753), // #3690c0
(0.750, 0.020, 0.439, 0.690), // #0570b0
(0.875, 0.016, 0.353, 0.553), // #045a8d
(1.000, 0.008, 0.220, 0.345), // #023858
],
t,
),
ColorMap::PuRd => Self::interpolate_stops(
&[
(0.000, 0.969, 0.957, 0.976), // #f7f4f9
(0.125, 0.906, 0.882, 0.937), // #e7e1ef
(0.250, 0.831, 0.725, 0.855), // #d4b9da
(0.375, 0.788, 0.580, 0.780), // #c994c7
(0.500, 0.875, 0.396, 0.690), // #df65b0
(0.625, 0.906, 0.161, 0.541), // #e7298a
(0.750, 0.808, 0.071, 0.337), // #ce1256
(0.875, 0.596, 0.000, 0.263), // #980043
(1.000, 0.404, 0.000, 0.122), // #67001f
],
t,
),
ColorMap::RdPu => Self::interpolate_stops(
&[
(0.000, 1.000, 0.969, 0.953), // #fff7f3
(0.125, 0.992, 0.878, 0.867), // #fde0dd
(0.250, 0.988, 0.773, 0.753), // #fcc5c0
(0.375, 0.980, 0.624, 0.710), // #fa9fb5
(0.500, 0.969, 0.408, 0.631), // #f768a1
(0.625, 0.867, 0.204, 0.592), // #dd3497
(0.750, 0.682, 0.004, 0.494), // #ae017e
(0.875, 0.478, 0.004, 0.467), // #7a0177
(1.000, 0.286, 0.000, 0.416), // #49006a
],
t,
),
ColorMap::YlGnBu => Self::interpolate_stops(
&[
(0.000, 1.000, 1.000, 0.851), // #ffffd9
(0.125, 0.929, 0.973, 0.694), // #edf8b1
(0.250, 0.780, 0.914, 0.706), // #c7e9b4
(0.375, 0.498, 0.804, 0.733), // #7fcdbb
(0.500, 0.255, 0.714, 0.769), // #41b6c4
(0.625, 0.114, 0.569, 0.753), // #1d91c0
(0.750, 0.133, 0.369, 0.659), // #225ea8
(0.875, 0.145, 0.204, 0.580), // #253494
(1.000, 0.031, 0.114, 0.345), // #081d58
],
t,
),
ColorMap::YlGn => Self::interpolate_stops(
&[
(0.000, 1.000, 1.000, 0.898), // #ffffe5
(0.125, 0.969, 0.988, 0.725), // #f7fcb9
(0.250, 0.851, 0.941, 0.639), // #d9f0a3
(0.375, 0.678, 0.867, 0.557), // #addd8e
(0.500, 0.471, 0.776, 0.475), // #78c679
(0.625, 0.255, 0.671, 0.365), // #41ab5d
(0.750, 0.137, 0.518, 0.263), // #238443
(0.875, 0.000, 0.408, 0.216), // #006837
(1.000, 0.000, 0.271, 0.161), // #004529
],
t,
),
ColorMap::YlOrBr => Self::interpolate_stops(
&[
(0.000, 1.000, 1.000, 0.898), // #ffffe5
(0.125, 1.000, 0.969, 0.737), // #fff7bc
(0.250, 0.996, 0.890, 0.569), // #fee391
(0.375, 0.996, 0.769, 0.310), // #fec44f
(0.500, 0.996, 0.600, 0.161), // #fe9929
(0.625, 0.925, 0.439, 0.078), // #ec7014
(0.750, 0.800, 0.298, 0.008), // #cc4c02
(0.875, 0.600, 0.204, 0.016), // #993404
(1.000, 0.400, 0.145, 0.024), // #662506
],
t,
),
ColorMap::YlOrRd => Self::interpolate_stops(
&[
(0.000, 1.000, 1.000, 0.800), // #ffffcc
(0.125, 1.000, 0.929, 0.627), // #ffeda0
(0.250, 0.996, 0.851, 0.463), // #fed976
(0.375, 0.996, 0.698, 0.298), // #feb24c
(0.500, 0.992, 0.553, 0.235), // #fd8d3c
(0.625, 0.988, 0.306, 0.165), // #fc4e2a
(0.750, 0.890, 0.102, 0.110), // #e31a1c
(0.875, 0.741, 0.000, 0.149), // #bd0026
(1.000, 0.502, 0.000, 0.149), // #800026
],
t,
),
// --- Specialized ---
ColorMap::Rainbow => Self::hsv_to_rgb((1.0 - t) * 300.0, 1.0, 1.0),
ColorMap::Jet => Self::interpolate_stops(
&[
(0.00, 0.0, 0.0, 1.0),
(0.33, 0.0, 1.0, 1.0),
(0.66, 1.0, 1.0, 0.0),
(1.00, 1.0, 0.0, 0.0),
],
t,
),
ColorMap::Hot => {
if t < 0.33 {
SingleColor::from_rgba(t / 0.33, 0.0, 0.0, 1.0)
} else if t < 0.66 {
SingleColor::from_rgba(1.0, (t - 0.33) / 0.33, 0.0, 1.0)
} else {
SingleColor::from_rgba(1.0, 1.0, (t - 0.66) / 0.34, 1.0)
}
}
ColorMap::Cool => SingleColor::from_rgba(t, 1.0 - t, 1.0, 1.0),
}
}
/// Linearly interpolates between RGB stops. Alpha remains 1.0 by convention.
fn interpolate_stops(stops: &[(f64, f64, f64, f64)], t: f64) -> SingleColor {
let first = stops[0];
let last = stops[stops.len() - 1];
if t <= first.0 {
return SingleColor::from_rgba(first.1, first.2, first.3, 1.0);
}
if t >= last.0 {
return SingleColor::from_rgba(last.1, last.2, last.3, 1.0);
}
for i in 0..stops.len() - 1 {
let (p1, r1, g1, b1) = stops[i];
let (p2, r2, g2, b2) = stops[i + 1];
if t >= p1 && t <= p2 {
let f = (t - p1) / (p2 - p1);
return SingleColor::from_rgba(
r1 + f * (r2 - r1),
g1 + f * (g2 - g1),
b1 + f * (b2 - b1),
1.0,
);
}
}
SingleColor::from_rgba(first.1, first.2, first.3, 1.0)
}
fn hsv_to_rgb(h: f64, s: f64, v: f64) -> SingleColor {
// Ensure hue is within [0.0, 360.0) range using Euclidean remainder
let h = h.rem_euclid(360.0);
// Chroma: the intensity of the color
let c = v * s;
// x: intermediate value for the second largest component
let h_prime = h / 60.0;
let x = c * (1.0 - (h_prime % 2.0 - 1.0).abs());
// m: matching value to add to each component to match lightness (value)
let m = v - c;
// Determine R', G', B' based on which 60-degree sector of the color wheel we are in
let (r_prime, g_prime, b_prime) = if h_prime < 1.0 {
(c, x, 0.0)
} else if h_prime < 2.0 {
(x, c, 0.0)
} else if h_prime < 3.0 {
(0.0, c, x)
} else if h_prime < 4.0 {
(0.0, x, c)
} else if h_prime < 5.0 {
(x, 0.0, c)
} else {
(c, 0.0, x)
};
// Add m to each component and return as SingleColor (Alpha set to 1.0)
SingleColor::from_rgba(r_prime + m, g_prime + m, b_prime + m, 1.0)
}
}
/// Discrete color palettes for categorical data visualization.
/// Optimized to return `SingleColor` with pre-calculated f64 RGBA values.
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum ColorPalette {
Tab10,
Tab20,
Set1,
Set2,
Set3,
Pastel1,
Pastel2,
Dark2,
Accent,
}
impl ColorPalette {
/// Returns a specific color from the palette by index (with automatic wrapping).
/// Bypasses hex parsing by using pre-calculated RGBA components.
pub(crate) fn get_color(&self, index: usize) -> SingleColor {
let colors = self.rgba_colors();
let (r, g, b) = colors[index % colors.len()];
SingleColor::from_rgba(r, g, b, 1.0)
}
/// Internal storage of palette colors as normalized (r, g, b) f64 tuples.
/// This avoids hex string parsing at runtime.
fn rgba_colors(&self) -> &'static [(f64, f64, f64)] {
match self {
ColorPalette::Tab10 => &[
(0.122, 0.467, 0.706),
(1.000, 0.498, 0.055),
(0.173, 0.627, 0.173),
(0.839, 0.153, 0.157),
(0.580, 0.404, 0.741),
(0.549, 0.337, 0.294),
(0.890, 0.467, 0.761),
(0.498, 0.498, 0.498),
(0.737, 0.741, 0.133),
(0.090, 0.745, 0.812),
],
ColorPalette::Tab20 => &[
(0.122, 0.467, 0.706),
(0.682, 0.780, 0.910),
(1.000, 0.498, 0.055),
(1.000, 0.733, 0.471),
(0.173, 0.627, 0.173),
(0.596, 0.875, 0.541),
(0.839, 0.153, 0.157),
(1.000, 0.596, 0.588),
(0.580, 0.404, 0.741),
(0.773, 0.690, 0.835),
(0.549, 0.337, 0.294),
(0.769, 0.612, 0.580),
(0.890, 0.467, 0.761),
(0.969, 0.714, 0.824),
(0.498, 0.498, 0.498),
(0.780, 0.780, 0.780),
(0.737, 0.741, 0.133),
(0.859, 0.859, 0.553),
(0.090, 0.745, 0.812),
(0.620, 0.855, 0.898),
],
ColorPalette::Set1 => &[
(0.894, 0.102, 0.110),
(0.216, 0.494, 0.722),
(0.302, 0.686, 0.290),
(0.596, 0.306, 0.639),
(1.000, 0.498, 0.000),
(1.000, 1.000, 0.200),
(0.651, 0.337, 0.157),
(0.969, 0.506, 0.749),
(0.600, 0.600, 0.600),
],
ColorPalette::Set2 => &[
(0.400, 0.761, 0.647),
(0.988, 0.553, 0.384),
(0.553, 0.627, 0.796),
(0.906, 0.541, 0.765),
(0.651, 0.847, 0.329),
(1.000, 0.851, 0.184),
(0.898, 0.769, 0.580),
(0.702, 0.702, 0.702),
],
ColorPalette::Set3 => &[
(0.553, 0.827, 0.780),
(1.000, 1.000, 0.702),
(0.745, 0.729, 0.855),
(0.984, 0.502, 0.447),
(0.502, 0.694, 0.827),
(0.992, 0.706, 0.384),
(0.702, 0.871, 0.412),
(0.988, 0.804, 0.898),
(0.851, 0.851, 0.851),
(0.737, 0.502, 0.741),
(0.800, 0.922, 0.773),
(1.000, 0.929, 0.435),
],
ColorPalette::Pastel1 => &[
(0.984, 0.706, 0.682),
(0.702, 0.804, 0.890),
(0.800, 0.922, 0.773),
(0.871, 0.796, 0.894),
(0.996, 0.851, 0.651),
(1.000, 1.000, 0.800),
(0.898, 0.847, 0.741),
(0.992, 0.855, 0.925),
(0.949, 0.949, 0.949),
],
ColorPalette::Pastel2 => &[
(0.702, 0.886, 0.804),
(0.992, 0.804, 0.675),
(0.796, 0.835, 0.910),
(0.957, 0.792, 0.894),
(0.902, 0.961, 0.788),
(1.000, 0.949, 0.682),
(0.945, 0.886, 0.800),
(0.800, 0.800, 0.800),
],
ColorPalette::Dark2 => &[
(0.106, 0.620, 0.467),
(0.851, 0.373, 0.008),
(0.459, 0.439, 0.702),
(0.906, 0.161, 0.541),
(0.400, 0.651, 0.118),
(0.902, 0.671, 0.008),
(0.651, 0.463, 0.114),
(0.400, 0.400, 0.400),
],
ColorPalette::Accent => &[
(0.498, 0.788, 0.498),
(0.745, 0.682, 0.831),
(0.992, 0.753, 0.525),
(1.000, 1.000, 0.600),
(0.220, 0.424, 0.690),
(0.941, 0.008, 0.498),
(0.749, 0.357, 0.090),
(0.400, 0.400, 0.400),
],
}
}
}
/// A lightweight, copyable color representation using normalized RGBA values.
///
/// By storing only numerical values, this struct is optimized for:
/// 1. **Memory Efficiency**: It implements `Copy`, allowing it to be passed
/// by value without heap allocations.
/// 2. **GPU Performance**: The `[Precision; 4]` array maps directly to
/// GPU vertex buffers (f32) without runtime conversion.
/// 3. **Backend Agnostic**: SVG strings are generated on-the-fly only when
/// needed, ensuring no redundant memory is used for thousands of points.
///
/// This version integrates `csscolorparser` to allow creation from CSS strings
/// (like "#ff0000" or "rgba(255,0,0,0.5)") while maintaining a stack-allocated
/// internal structure for performance.
#[derive(Clone, Copy, Debug, Default, PartialEq)]
pub struct SingleColor {
/// Pre-parsed RGBA normalized values [0.0 - 1.0].
rgba: [Precision; 4],
}
impl SingleColor {
/// Creates a new `SingleColor` by parsing a CSS color string.
///
/// If parsing fails, it defaults to opaque black.
/// Supports: Hex, RGB, RGBA, HSL, and named colors.
pub fn new(color_str: &str) -> Self {
let color_lc = color_str.to_lowercase();
// Handle the "none" state which is common in SVG but not always
// in standard CSS parsers.
if color_lc == "none" || color_lc == "transparent" {
return Self::none();
}
// Parse using csscolorparser
let parsed = color_str.parse::<Color>().unwrap_or_else(|_| {
// Fallback to opaque black on error
Color::new(0.0, 0.0, 0.0, 1.0)
});
Self {
rgba: [
parsed.r as Precision,
parsed.g as Precision,
parsed.b as Precision,
parsed.a as Precision,
],
}
}
pub fn none() -> Self {
Self {
rgba: [0.0, 0.0, 0.0, 0.0],
}
}
pub fn from_rgba(r: f64, g: f64, b: f64, a: f64) -> Self {
Self {
rgba: [
r.clamp(0.0, 1.0) as Precision,
g.clamp(0.0, 1.0) as Precision,
b.clamp(0.0, 1.0) as Precision,
a.clamp(0.0, 1.0) as Precision,
],
}
}
pub fn rgba(&self) -> [Precision; 4] {
self.rgba
}
pub fn is_none(&self) -> bool {
self.rgba[3] <= 0.0
}
/// Generates a CSS-compatible string.
/// Note: This allocates a new String. Use sparingly in tight loops.
pub fn to_css_string(&self) -> String {
if self.is_none() {
"none".to_string()
} else {
let c = self.rgba;
format!(
"rgba({},{},{},{:.3})",
(c[0] * 255.0).round() as u8,
(c[1] * 255.0).round() as u8,
(c[2] * 255.0).round() as u8,
c[3]
)
}
}
}
// --- Fluent API Support ---
impl From<&str> for SingleColor {
/// Allows: let c: SingleColor = "#ff0000".into();
fn from(s: &str) -> Self {
Self::new(s)
}
}
impl From<String> for SingleColor {
/// Allows: let c: SingleColor = String::from("red").into();
fn from(s: String) -> Self {
Self::new(&s)
}
}
impl From<[f64; 4]> for SingleColor {
fn from(c: [f64; 4]) -> Self {
Self::from_rgba(c[0], c[1], c[2], c[3])
}
}