colorbox 0.4.0

A low-level toolbox for working with color
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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235

//! IRIDAS .cube LUT format.
//!
//! This format can contain either a 1D LUT or a 3D LUT, but not both,
//! and there is no indication in the file extension which is which.

use std::io::{BufRead, Write};

use super::filter_non_finite;
use crate::lut::{Lut1D, Lut3D};

/// Writes a 1D .cube file.
pub fn write_1d<W: Write>(
    mut writer: W,
    ranges: [(f32, f32); 3],
    tables: [&[f32]; 3],
) -> std::io::Result<()> {
    assert!(tables[0].len() == tables[1].len() && tables[1].len() == tables[2].len());

    writer.write_all(b"TITLE \"untitled\"\n")?;
    writer.write_all(
        format!(
            "DOMAIN_MIN {} {} {}\n",
            filter_non_finite(ranges[0].0),
            filter_non_finite(ranges[1].0),
            filter_non_finite(ranges[2].0),
        )
        .as_bytes(),
    )?;
    writer.write_all(
        format!(
            "DOMAIN_MAX {} {} {}\n",
            filter_non_finite(ranges[0].1),
            filter_non_finite(ranges[1].1),
            filter_non_finite(ranges[2].1),
        )
        .as_bytes(),
    )?;
    writer.write_all(format!("LUT_1D_SIZE {}\n", tables[0].len()).as_bytes())?;

    for ((r, g), b) in tables[0]
        .iter()
        .copied()
        .zip(tables[1].iter().copied())
        .zip(tables[2].iter().copied())
    {
        writer.write_all(
            format!(
                "{} {} {}\n",
                filter_non_finite(r),
                filter_non_finite(g),
                filter_non_finite(b),
            )
            .as_bytes(),
        )?;
    }

    Ok(())
}

/// Writes a 3D .cube file.
///
/// The tables should have a length of `resolution * resolution * resolution`,
/// and their indices should be ordered the same as the `Lut3D` type.
pub fn write_3d<W: Write>(
    mut writer: W,
    ranges: [(f32, f32); 3],
    resolution: usize,
    tables: [&[f32]; 3],
) -> std::io::Result<()> {
    assert!(tables[0].len() == (resolution * resolution * resolution));
    assert!(tables[0].len() == tables[1].len() && tables[1].len() == tables[2].len());

    writer.write_all(b"TITLE \"untitled\"\n")?;
    writer.write_all(
        format!(
            "DOMAIN_MIN {} {} {}\n",
            filter_non_finite(ranges[0].0),
            filter_non_finite(ranges[1].0),
            filter_non_finite(ranges[2].0),
        )
        .as_bytes(),
    )?;
    writer.write_all(
        format!(
            "DOMAIN_MAX {} {} {}\n",
            filter_non_finite(ranges[0].1),
            filter_non_finite(ranges[1].1),
            filter_non_finite(ranges[2].1),
        )
        .as_bytes(),
    )?;
    writer.write_all(format!("LUT_3D_SIZE {}\n", resolution).as_bytes())?;

    for ((r, g), b) in tables[0]
        .iter()
        .copied()
        .zip(tables[1].iter().copied())
        .zip(tables[2].iter().copied())
    {
        writer.write_all(
            format!(
                "{} {} {}\n",
                filter_non_finite(r),
                filter_non_finite(g),
                filter_non_finite(b),
            )
            .as_bytes(),
        )?;
    }

    Ok(())
}

/// Reads a 1D .cube file.
pub fn read_1d<R: BufRead>(reader: R) -> Result<Lut1D, super::ReadError> {
    // let mut name: Option<String> = None;
    let mut ranges = [(0.0f32, 1.0f32); 3];
    let mut length = None;
    let mut tables = [Vec::new(), Vec::new(), Vec::new()];

    for line in reader.lines() {
        let line = line?;
        let parts: Vec<_> = line.split_whitespace().collect();

        if parts.is_empty() || parts[0].starts_with("#") {
            continue;
        } else if parts[0] == "TITLE" && parts.len() > 1 {
            let name_parts: Vec<_> = line.trim().split("\"").collect();
            if name_parts.len() != 3 || !name_parts[2].is_empty() {
                return Err(super::ReadError::FormatErr);
            }
            // name = Some(name_parts[1].into());
            continue;
        } else if parts[0] == "DOMAIN_MIN" && parts.len() == 4 {
            ranges[0].0 = parts[1].parse::<f32>()?;
            ranges[1].0 = parts[2].parse::<f32>()?;
            ranges[2].0 = parts[3].parse::<f32>()?;
            continue;
        } else if parts[0] == "DOMAIN_MAX" && parts.len() == 4 {
            ranges[0].1 = parts[1].parse::<f32>()?;
            ranges[1].1 = parts[2].parse::<f32>()?;
            ranges[2].1 = parts[3].parse::<f32>()?;
            continue;
        } else if parts[0] == "LUT_1D_SIZE" && parts.len() == 2 {
            length = Some(parts[1].parse::<usize>()?);
            continue;
        } else if parts.len() == 3 {
            tables[0].push(parts[0].parse::<f32>()?);
            tables[1].push(parts[1].parse::<f32>()?);
            tables[2].push(parts[2].parse::<f32>()?);
            continue;
        } else {
            // Line didn't match any acceptable pattern.
            return Err(super::ReadError::FormatErr);
        }
    }

    if !tables.iter().flatten().all(|n| n.is_finite())
        || !ranges.iter().all(|(a, b)| a.is_finite() && b.is_finite())
    {
        // Non-finite values in the file.
        return Err(super::ReadError::FormatErr);
    }

    let [table_r, table_g, table_b] = tables;
    match length {
        Some(len) if len == table_r.len() => Ok(Lut1D {
            ranges: vec![ranges[0], ranges[1], ranges[2]],
            tables: vec![table_r, table_g, table_b],
        }),
        _ => Err(super::ReadError::FormatErr),
    }
}

/// Reads a 3D .cube file.
pub fn read_3d<R: BufRead>(reader: R) -> Result<Lut3D, super::ReadError> {
    // let mut name: Option<String> = None;
    let mut ranges = [(0.0f32, 1.0f32); 3];
    let mut resolution = None;
    let mut tables = [Vec::new(), Vec::new(), Vec::new()];

    for line in reader.lines() {
        let line = line?;
        let parts: Vec<_> = line.split_whitespace().collect();

        if parts.is_empty() || parts[0].starts_with("#") {
            continue;
        } else if parts[0] == "TITLE" && parts.len() > 1 {
            let name_parts: Vec<_> = line.trim().split("\"").collect();
            if name_parts.len() != 3 || !name_parts[2].is_empty() {
                return Err(super::ReadError::FormatErr);
            }
            // name = Some(name_parts[1].into());
            continue;
        } else if parts[0] == "DOMAIN_MIN" && parts.len() == 4 {
            ranges[0].0 = parts[1].parse::<f32>()?;
            ranges[1].0 = parts[2].parse::<f32>()?;
            ranges[2].0 = parts[3].parse::<f32>()?;
            continue;
        } else if parts[0] == "DOMAIN_MAX" && parts.len() == 4 {
            ranges[0].1 = parts[1].parse::<f32>()?;
            ranges[1].1 = parts[2].parse::<f32>()?;
            ranges[2].1 = parts[3].parse::<f32>()?;
            continue;
        } else if parts[0] == "LUT_3D_SIZE" && parts.len() == 2 {
            resolution = Some(parts[1].parse::<usize>()?);
            continue;
        } else if parts.len() == 3 {
            tables[0].push(parts[0].parse::<f32>()?);
            tables[1].push(parts[1].parse::<f32>()?);
            tables[2].push(parts[2].parse::<f32>()?);
            continue;
        } else {
            // Line didn't match any acceptable pattern.
            return Err(super::ReadError::FormatErr);
        }
    }

    if !tables.iter().flatten().all(|n| n.is_finite())
        || !ranges.iter().all(|(a, b)| a.is_finite() && b.is_finite())
    {
        // Non-finite values in the file.
        return Err(super::ReadError::FormatErr);
    }

    let [table_r, table_g, table_b] = tables;
    match resolution {
        Some(res) if (res * res * res) == table_r.len() => Ok(Lut3D {
            range: ranges,
            resolution: [res, res, res],
            tables: vec![table_r, table_g, table_b],
        }),
        _ => Err(super::ReadError::FormatErr),
    }
}