pixeli 0.2.1

This crate provides common pixel types and traits for working with them.
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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176

/// Convert between pixel component types using common component ranges.
pub trait FromComponentCommon<T> {
    /// Converts to this type from the input component type.
    fn from_component_common(component: T) -> Self;
}
impl<T> FromComponentCommon<T> for T {
    fn from_component_common(component: T) -> Self {
        component
    }
}

macro_rules! float_integer {
    ($float:ident, $from:ident) => {
        impl FromComponentCommon<$from> for $float {
            fn from_component_common(component: $from) -> Self {
                ((component as $float - $from::MIN as $float)
                    / ($from::MAX as $float - $from::MIN as $float))
                    .clamp(0.0, 1.0)
            }
        }
        impl FromComponentCommon<$float> for $from {
            fn from_component_common(component: $float) -> Self {
                #[allow(unused_imports)]
                use num_traits::Float;

                (component.clamp(0.0, 1.0)
                    * $float::from($from::MAX as $float - $from::MIN as $float))
                .round() as $from
            }
        }
    };
}
macro_rules! integer_integer {
    ($int1:ident, $int2:ident) => {
        impl FromComponentCommon<$int1> for $int2 {
            fn from_component_common(component: $int1) -> Self {
                Self::from_component_common(f64::from_component_common(component))
            }
        }
        impl FromComponentCommon<$int2> for $int1 {
            fn from_component_common(component: $int2) -> Self {
                Self::from_component_common(f64::from_component_common(component))
            }
        }
    };
}

impl FromComponentCommon<f32> for f64 {
    fn from_component_common(component: f32) -> Self {
        component as f64
    }
}
impl FromComponentCommon<f64> for f32 {
    fn from_component_common(component: f64) -> Self {
        component as f32
    }
}

float_integer!(f32, u8);
float_integer!(f32, u16);
float_integer!(f32, u32);
float_integer!(f32, u64);
float_integer!(f32, u128);
float_integer!(f32, i8);
float_integer!(f32, i16);
float_integer!(f32, i32);
float_integer!(f32, i64);
float_integer!(f32, i128);
float_integer!(f32, usize);
float_integer!(f32, isize);

float_integer!(f64, u8);
float_integer!(f64, u16);
float_integer!(f64, u32);
float_integer!(f64, u64);
float_integer!(f64, u128);
float_integer!(f64, i8);
float_integer!(f64, i16);
float_integer!(f64, i32);
float_integer!(f64, i64);
float_integer!(f64, i128);
float_integer!(f64, usize);
float_integer!(f64, isize);

impl FromComponentCommon<u8> for u16 {
    fn from_component_common(component: u8) -> Self {
        let x = u16::from(component);
        (x << 8) | x
    }
}
impl FromComponentCommon<u16> for u8 {
    fn from_component_common(component: u16) -> Self {
        // The input c is the numerator of `c / u16::MAX`.
        // Derive numerator of `num / u8::MAX`, with rounding.
        //
        // This method is based on the inverse (see FromPrimitive<u8> for u16) and was tested
        // exhaustively in Python. It's the same as the reference function:
        //  round(c * (2**8 - 1) / (2**16 - 1))
        ((u32::from(component) + 128) / 257) as u8
    }
}
integer_integer!(u8, u32);
integer_integer!(u8, u64);
integer_integer!(u8, u128);
integer_integer!(u8, i8);
integer_integer!(u8, i16);
integer_integer!(u8, i32);
integer_integer!(u8, i64);
integer_integer!(u8, i128);
integer_integer!(u8, usize);
integer_integer!(u8, isize);

integer_integer!(u16, u32);
integer_integer!(u16, u64);
integer_integer!(u16, u128);
integer_integer!(u16, i8);
integer_integer!(u16, i16);
integer_integer!(u16, i32);
integer_integer!(u16, i64);
integer_integer!(u16, i128);
integer_integer!(u16, usize);
integer_integer!(u16, isize);

integer_integer!(u32, u64);
integer_integer!(u32, u128);
integer_integer!(u32, i8);
integer_integer!(u32, i16);
integer_integer!(u32, i32);
integer_integer!(u32, i64);
integer_integer!(u32, i128);
integer_integer!(u32, usize);
integer_integer!(u32, isize);

integer_integer!(u64, u128);
integer_integer!(u64, i8);
integer_integer!(u64, i16);
integer_integer!(u64, i32);
integer_integer!(u64, i64);
integer_integer!(u64, i128);
integer_integer!(u64, usize);
integer_integer!(u64, isize);

integer_integer!(u128, i8);
integer_integer!(u128, i16);
integer_integer!(u128, i32);
integer_integer!(u128, i64);
integer_integer!(u128, i128);
integer_integer!(u128, usize);
integer_integer!(u128, isize);

integer_integer!(i8, i16);
integer_integer!(i8, i32);
integer_integer!(i8, i64);
integer_integer!(i8, i128);
integer_integer!(i8, usize);
integer_integer!(i8, isize);

integer_integer!(i16, i32);
integer_integer!(i16, i64);
integer_integer!(i16, i128);
integer_integer!(i16, usize);
integer_integer!(i16, isize);

integer_integer!(i32, i64);
integer_integer!(i32, i128);
integer_integer!(i32, usize);
integer_integer!(i32, isize);

integer_integer!(i64, i128);
integer_integer!(i64, usize);
integer_integer!(i64, isize);

integer_integer!(i128, usize);
integer_integer!(i128, isize);

integer_integer!(usize, isize);