1#![allow(dead_code)]
2
3use serde::de::{self, Deserialize, Deserializer, Visitor};
4use std::fmt;
5use std::num::ParseIntError;
6
7pub fn rgb<C: From<Rgba>>(hex: u32) -> C {
8 let r = ((hex >> 16) & 0xFF) as f32 / 255.0;
9 let g = ((hex >> 8) & 0xFF) as f32 / 255.0;
10 let b = (hex & 0xFF) as f32 / 255.0;
11 Rgba { r, g, b, a: 1.0 }.into()
12}
13
14pub fn rgba(hex: u32) -> Rgba {
15 let r = ((hex >> 24) & 0xFF) as f32 / 255.0;
16 let g = ((hex >> 16) & 0xFF) as f32 / 255.0;
17 let b = ((hex >> 8) & 0xFF) as f32 / 255.0;
18 let a = (hex & 0xFF) as f32 / 255.0;
19 Rgba { r, g, b, a }
20}
21
22#[derive(Clone, Copy, Default)]
23pub struct Rgba {
24 pub r: f32,
25 pub g: f32,
26 pub b: f32,
27 pub a: f32,
28}
29
30impl fmt::Debug for Rgba {
31 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
32 write!(f, "rgba({:#010x})", u32::from(*self))
33 }
34}
35
36impl Rgba {
37 pub fn blend(&self, other: Rgba) -> Self {
38 if other.a >= 1.0 {
39 return other;
40 } else if other.a <= 0.0 {
41 return *self;
42 } else {
43 return Rgba {
44 r: (self.r * (1.0 - other.a)) + (other.r * other.a),
45 g: (self.g * (1.0 - other.a)) + (other.g * other.a),
46 b: (self.b * (1.0 - other.a)) + (other.b * other.a),
47 a: self.a,
48 };
49 }
50 }
51}
52
53impl From<Rgba> for u32 {
54 fn from(rgba: Rgba) -> Self {
55 let r = (rgba.r * 255.0) as u32;
56 let g = (rgba.g * 255.0) as u32;
57 let b = (rgba.b * 255.0) as u32;
58 let a = (rgba.a * 255.0) as u32;
59 (r << 24) | (g << 16) | (b << 8) | a
60 }
61}
62
63
64struct RgbaVisitor;
65
66impl<'de> Visitor<'de> for RgbaVisitor {
67 type Value = Rgba;
68
69 fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
70 formatter.write_str("a string in the format #rrggbb or #rrggbbaa")
71 }
72
73 fn visit_str<E: de::Error>(self, value: &str) -> Result<Rgba, E> {
74 if value.len() == 7 || value.len() == 9 {
75 let r = u8::from_str_radix(&value[1..3], 16).unwrap() as f32 / 255.0;
76 let g = u8::from_str_radix(&value[3..5], 16).unwrap() as f32 / 255.0;
77 let b = u8::from_str_radix(&value[5..7], 16).unwrap() as f32 / 255.0;
78 let a = if value.len() == 9 {
79 u8::from_str_radix(&value[7..9], 16).unwrap() as f32 / 255.0
80 } else {
81 1.0
82 };
83 Ok(Rgba { r, g, b, a })
84 } else {
85 Err(E::custom(
86 "Bad format for RGBA. Expected #rrggbb or #rrggbbaa.",
87 ))
88 }
89 }
90}
91
92impl<'de> Deserialize<'de> for Rgba {
93 fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
94 deserializer.deserialize_str(RgbaVisitor)
95 }
96}
97
98impl From<Hsla> for Rgba {
99 fn from(color: Hsla) -> Self {
100 let h = color.h;
101 let s = color.s;
102 let l = color.l;
103
104 let c = (1.0 - (2.0 * l - 1.0).abs()) * s;
105 let x = c * (1.0 - ((h * 6.0) % 2.0 - 1.0).abs());
106 let m = l - c / 2.0;
107 let cm = c + m;
108 let xm = x + m;
109
110 let (r, g, b) = match (h * 6.0).floor() as i32 {
111 0 | 6 => (cm, xm, m),
112 1 => (xm, cm, m),
113 2 => (m, cm, xm),
114 3 => (m, xm, cm),
115 4 => (xm, m, cm),
116 _ => (cm, m, xm),
117 };
118
119 Rgba {
120 r,
121 g,
122 b,
123 a: color.a,
124 }
125 }
126}
127
128impl TryFrom<&'_ str> for Rgba {
129 type Error = ParseIntError;
130
131 fn try_from(value: &'_ str) -> Result<Self, Self::Error> {
132 let r = u8::from_str_radix(&value[1..3], 16)? as f32 / 255.0;
133 let g = u8::from_str_radix(&value[3..5], 16)? as f32 / 255.0;
134 let b = u8::from_str_radix(&value[5..7], 16)? as f32 / 255.0;
135 let a = if value.len() > 7 {
136 u8::from_str_radix(&value[7..9], 16)? as f32 / 255.0
137 } else {
138 1.0
139 };
140
141 Ok(Rgba { r, g, b, a })
142 }
143}
144
145#[derive(Default, Copy, Clone, Debug, PartialEq)]
146#[repr(C)]
147pub struct Hsla {
148 pub h: f32,
149 pub s: f32,
150 pub l: f32,
151 pub a: f32,
152}
153
154impl Hsla {
155 pub fn to_rgb(self) -> Rgba {
156 self.into()
157 }
158}
159
160
161impl Eq for Hsla {}
162
163
164pub fn hsla(h: f32, s: f32, l: f32, a: f32) -> Hsla {
165 Hsla {
166 h: h.clamp(0., 1.),
167 s: s.clamp(0., 1.),
168 l: l.clamp(0., 1.),
169 a: a.clamp(0., 1.),
170 }
171}
172
173pub fn black() -> Hsla {
174 Hsla {
175 h: 0.,
176 s: 0.,
177 l: 0.,
178 a: 1.,
179 }
180}
181
182pub fn white() -> Hsla {
183 Hsla {
184 h: 0.,
185 s: 0.,
186 l: 1.,
187 a: 1.,
188 }
189}
190
191pub fn red() -> Hsla {
192 Hsla {
193 h: 0.,
194 s: 1.,
195 l: 0.5,
196 a: 1.,
197 }
198}
199
200impl Hsla {
201 /// Returns true if the HSLA color is fully transparent, false otherwise.
202 pub fn is_transparent(&self) -> bool {
203 self.a == 0.0
204 }
205
206 /// Blends `other` on top of `self` based on `other`'s alpha value. The resulting color is a combination of `self`'s and `other`'s colors.
207 ///
208 /// If `other`'s alpha value is 1.0 or greater, `other` color is fully opaque, thus `other` is returned as the output color.
209 /// If `other`'s alpha value is 0.0 or less, `other` color is fully transparent, thus `self` is returned as the output color.
210 /// Else, the output color is calculated as a blend of `self` and `other` based on their weighted alpha values.
211 ///
212 /// Assumptions:
213 /// - Alpha values are contained in the range [0, 1], with 1 as fully opaque and 0 as fully transparent.
214 /// - The relative contributions of `self` and `other` is based on `self`'s alpha value (`self.a`) and `other`'s alpha value (`other.a`), `self` contributing `self.a * (1.0 - other.a)` and `other` contributing it's own alpha value.
215 /// - RGB color components are contained in the range [0, 1].
216 /// - If `self` and `other` colors are out of the valid range, the blend operation's output and behavior is undefined.
217 pub fn blend(self, other: Hsla) -> Hsla {
218 let alpha = other.a;
219
220 if alpha >= 1.0 {
221 return other;
222 } else if alpha <= 0.0 {
223 return self;
224 } else {
225 let converted_self = Rgba::from(self);
226 let converted_other = Rgba::from(other);
227 let blended_rgb = converted_self.blend(converted_other);
228 return Hsla::from(blended_rgb);
229 }
230 }
231
232 /// Fade out the color by a given factor. This factor should be between 0.0 and 1.0.
233 /// Where 0.0 will leave the color unchanged, and 1.0 will completely fade out the color.
234 pub fn fade_out(&mut self, factor: f32) {
235 self.a *= 1.0 - factor.clamp(0., 1.);
236 }
237}
238
239// impl From<Hsla> for Rgba {
240// fn from(value: Hsla) -> Self {
241// let h = value.h;
242// let s = value.s;
243// let l = value.l;
244
245// let c = (1 - |2L - 1|) X s
246// }
247// }
248
249impl From<Rgba> for Hsla {
250 fn from(color: Rgba) -> Self {
251 let r = color.r;
252 let g = color.g;
253 let b = color.b;
254
255 let max = r.max(g.max(b));
256 let min = r.min(g.min(b));
257 let delta = max - min;
258
259 let l = (max + min) / 2.0;
260 let s = if l == 0.0 || l == 1.0 {
261 0.0
262 } else if l < 0.5 {
263 delta / (2.0 * l)
264 } else {
265 delta / (2.0 - 2.0 * l)
266 };
267
268 let h = if delta == 0.0 {
269 0.0
270 } else if max == r {
271 ((g - b) / delta).rem_euclid(6.0) / 6.0
272 } else if max == g {
273 ((b - r) / delta + 2.0) / 6.0
274 } else {
275 ((r - g) / delta + 4.0) / 6.0
276 };
277
278 Hsla {
279 h,
280 s,
281 l,
282 a: color.a,
283 }
284 }
285}
286
287impl<'de> Deserialize<'de> for Hsla {
288 fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
289 where
290 D: Deserializer<'de>,
291 {
292 // First, deserialize it into Rgba
293 let rgba = Rgba::deserialize(deserializer)?;
294
295 // Then, use the From<Rgba> for Hsla implementation to convert it
296 Ok(Hsla::from(rgba))
297 }
298}