prisma 0.1.1

A color library for both simple and complex color manipulation, intending to be the go to rust color library for most tasks. It can handle conversion between a large number of color models, and can convert into the CIE device independent color spaces. Prisma tries to be easy to use while encouraging correct transformations, making mathematically correct conversions easy without knowing the whole field of color science.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141

//! Defines the standard named color spaces as unit structs

#![allow(non_camel_case_types)]

use std::marker::PhantomData;

use crate::alpha::{Rgba, Xyza};
use crate::channel::{ChannelFormatCast, FreeChannelScalar, PosNormalChannelScalar};
use crate::color::Color;
use crate::color_space::{ColorSpace, EncodedColorSpace, RgbPrimary};
use crate::encoding::{ColorEncoding, EncodedColor, SrgbEncoding};
use crate::linalg::Matrix3;
use crate::rgb::Rgb;
use crate::white_point::{WhitePoint, D65};
use crate::xyz::Xyz;
use num_traits;
use num_traits::cast;

use crate::color_space::{ConvertFromXyz, ConvertToXyz, UnitColorSpace};

/// The sRgb color space
#[derive(Copy, Clone, Debug, PartialEq, Eq, Default)]
pub struct SRgb<T> {
    _marker: PhantomData<T>,
}

impl<T> SRgb<T> {
    /// Construct a new SRgb instance
    pub fn new() -> SRgb<T> {
        SRgb {
            _marker: PhantomData,
        }
    }
}

/// Use this macro to easily implement a new color space. You need the primaries, white point and
/// precomputed forward and backward transformation matrices.
macro_rules! impl_known_color_space {
    ($name:ident primaries=(($rx:expr, $ry:expr), ($gx:expr, $gy:expr), ($bx:expr, $by:expr)),
        wp=$wp:expr, enc=$enc:ident, mat=[$($m:expr),*], mat_inv=[$($m_inv:expr),*]) =>
    {
        impl<T> ColorSpace<T> for $name<T>
            where T: num_traits::Float + FreeChannelScalar + PosNormalChannelScalar
        {
            type Encoding = $enc;
            fn red_primary(&self) -> RgbPrimary<T> {
                RgbPrimary::new(cast($rx).unwrap(), cast($ry).unwrap())
            }
            fn green_primary(&self) -> RgbPrimary<T> {
                RgbPrimary::new(cast($gx).unwrap(), cast($gy).unwrap())
            }
            fn blue_primary(&self) -> RgbPrimary<T> {
                RgbPrimary::new(cast($bx).unwrap(), cast($by).unwrap())
            }
            fn white_point(&self) -> Xyz<T> {
                $wp.get_xyz()
            }
            fn get_xyz_transform(&self) -> Matrix3<T> {
                Matrix3::new([$(cast($m).unwrap()),*])
            }
            fn get_inverse_xyz_transform(&self) -> Matrix3<T> {
                Matrix3::new([$(cast($m_inv).unwrap()),*])
            }
            fn encoding(&self) -> Self::Encoding {
                Self::Encoding::default()
            }
            fn apply_transform(&self, vec: (T, T, T)) -> (T, T, T) {
                self.get_xyz_transform().transform_vector(vec)
            }
        }
        impl<T> UnitColorSpace<T> for $name<T>
            where T: num_traits::Float + FreeChannelScalar + PosNormalChannelScalar
        {
            fn build_color_space_instance() -> EncodedColorSpace<T, Self::Encoding> {
                EncodedColorSpace::new(
                    RgbPrimary::new(cast($rx).unwrap(), cast($ry).unwrap()),
                    RgbPrimary::new(cast($gx).unwrap(), cast($gy).unwrap()),
                    RgbPrimary::new(cast($bx).unwrap(), cast($by).unwrap()),
                    $wp.get_xyz(),
                    $enc::default(),
                )
            }
        }
        impl<T, E> ConvertToXyz<T, Rgb<T>, E> for $name<T>
        where
            T: num_traits::Float + FreeChannelScalar + PosNormalChannelScalar + ChannelFormatCast<f64>,
            f64: ChannelFormatCast<T>,
            E: ColorEncoding,
        {
            type OutputColor = Xyz<T>;
            fn convert_to_xyz(&self, color: &EncodedColor<Rgb<T>, E>) -> Self::OutputColor {
                let linear_color = color.clone().decode();
                let (x, y, z) = self.get_xyz_transform().transform_vector(linear_color.to_tuple());
                Xyz::new(x, y, z)
            }
        }
        impl<T> ConvertFromXyz<T, Xyz<T>> for $name<T>
        where
            T: num_traits::Float + FreeChannelScalar + PosNormalChannelScalar + ChannelFormatCast<f64>,
            f64: ChannelFormatCast<T>,
        {
            type OutputColor = Rgb<T>;
            fn convert_from_xyz_raw(&self, color: &Xyz<T>) -> Rgb<T> {
                let (r, g, b) = self.get_inverse_xyz_transform().transform_vector(color.clone().to_tuple());
                Rgb::new(r, g, b)
            }
        }
        impl<T, E> ConvertToXyz<T, Rgba<T>, E> for $name<T>
        where
            T: num_traits::Float + FreeChannelScalar + PosNormalChannelScalar + ChannelFormatCast<f64>,
            f64: ChannelFormatCast<T>,
            E: ColorEncoding,
        {
            type OutputColor = Xyza<T>;
            fn convert_to_xyz(&self, color: &EncodedColor<Rgba<T>, E>) -> Self::OutputColor {
                let linear_color = color.clone().decode();
                let (x, y, z) = self.get_xyz_transform().transform_vector(linear_color.color().color().to_tuple());
                Xyza::new(Xyz::new(x, y, z), color.alpha())
            }
        }
        impl<T> ConvertFromXyz<T, Xyza<T>> for $name<T>
        where
            T: num_traits::Float + FreeChannelScalar + PosNormalChannelScalar + ChannelFormatCast<f64>,
            f64: ChannelFormatCast<T>,
        {
            type OutputColor = Rgba<T>;
            fn convert_from_xyz_raw(&self, color: &Xyza<T>) -> Rgba<T> {
                let (r, g, b) = self.get_inverse_xyz_transform().transform_vector((**color).clone().to_tuple());
                Rgba::new(Rgb::new(r, g, b), color.alpha())
            }
        }
    }
}

impl_known_color_space!(SRgb
    primaries=((0.6400, 0.3300), (0.300, 0.600), (0.150, 0.060)),
    wp=D65,
    enc=SrgbEncoding,
    mat=[0.41245643908969226, 0.3575760776439089, 0.1804374832663989, 0.21267285140562256, 0.7151521552878178, 0.07217499330655956, 0.019333895582329303, 0.11919202588130294, 0.9503040785363677],
    mat_inv=[3.2404541621141036, -1.537138512797716, -0.49853140955601594, -0.9692660305051867, 1.8760108454466942, 0.04155601753034982, 0.05564343095911471, -0.20402591351675378, 1.0572251882231791]
);