moxcms/
gamut.rs

1/*
2 * // Copyright (c) Radzivon Bartoshyk 3/2025. All rights reserved.
3 * //
4 * // Redistribution and use in source and binary forms, with or without modification,
5 * // are permitted provided that the following conditions are met:
6 * //
7 * // 1.  Redistributions of source code must retain the above copyright notice, this
8 * // list of conditions and the following disclaimer.
9 * //
10 * // 2.  Redistributions in binary form must reproduce the above copyright notice,
11 * // this list of conditions and the following disclaimer in the documentation
12 * // and/or other materials provided with the distribution.
13 * //
14 * // 3.  Neither the name of the copyright holder nor the names of its
15 * // contributors may be used to endorse or promote products derived from
16 * // this software without specific prior written permission.
17 * //
18 * // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
22 * // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24 * // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
25 * // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29use crate::Rgb;
30
31#[inline]
32fn filmlike_clip_rgb_tone(r: &mut f32, g: &mut f32, b: &mut f32, l: f32) {
33    let new_r = r.min(l);
34    let new_b = b.min(l);
35    let new_g = new_b + ((new_r - new_b) * (*g - *b) / (*r - *b));
36    *r = new_r;
37    *g = new_g;
38    *b = new_b;
39}
40
41/// Soft clipping out-of-bounds values in S-curve
42///
43/// Works only on highlights, negative values are skipped
44#[inline]
45pub fn filmlike_clip(rgb: Rgb<f32>) -> Rgb<f32> {
46    const L: f32 = 1.;
47    let mut rgb = rgb;
48    if rgb.r >= rgb.g {
49        if rgb.g > rgb.b {
50            filmlike_clip_rgb_tone(&mut rgb.r, &mut rgb.g, &mut rgb.b, L);
51        } else if rgb.b > rgb.r {
52            filmlike_clip_rgb_tone(&mut rgb.b, &mut rgb.r, &mut rgb.g, L);
53        } else if rgb.b > rgb.g {
54            filmlike_clip_rgb_tone(&mut rgb.r, &mut rgb.b, &mut rgb.g, L);
55        } else {
56            Rgb::new(rgb.r.min(L), rgb.g.min(L), rgb.g);
57        }
58    } else if rgb.r >= rgb.b {
59        filmlike_clip_rgb_tone(&mut rgb.g, &mut rgb.r, &mut rgb.b, L);
60    } else if rgb.b > rgb.g {
61        filmlike_clip_rgb_tone(&mut rgb.b, &mut rgb.g, &mut rgb.r, L);
62    } else {
63        filmlike_clip_rgb_tone(&mut rgb.g, &mut rgb.b, &mut rgb.r, L);
64    }
65    rgb
66}
moxcms/gamut.rs

moxcms/
gamut.rs
