gdsr 0.0.1-alpha.3

A GDSII reader and writer for Rust
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

pub fn eight_byte_real(value: f64) -> [u8; 8] {
    if value == 0.0 {
        return [0x00; 8];
    }

    let mut byte1: u8;
    let mut val = value;

    if val < 0.0 {
        byte1 = 0x80;
        val = -val;
    } else {
        byte1 = 0x00;
    }

    let fexp = val.log2() / 4.0;
    let mut exponent = fexp.ceil() as i32;

    if fexp == f64::from(exponent) {
        exponent += 1;
    }

    let mantissa = (val * 16.0_f64.powi(14 - exponent)) as u64;
    byte1 += (exponent + 64) as u8;

    let byte2 = (mantissa >> 48) as u8;
    let short3 = ((mantissa >> 32) & 0xFFFF) as u16;
    let long4 = (mantissa & 0xFFFF_FFFF) as u32;

    let mut result = [0u8; 8];
    result[0] = byte1;
    result[1] = byte2;
    result[2] = (short3 >> 8) as u8;
    result[3] = (short3 & 0xFF) as u8;
    result[4] = (long4 >> 24) as u8;
    result[5] = (long4 >> 16) as u8;
    result[6] = (long4 >> 8) as u8;
    result[7] = (long4 & 0xFF) as u8;

    result
}

pub fn write_u16_array_as_big_endian(
    buffer: &mut impl std::io::Write,
    array: &[u16],
) -> std::io::Result<()> {
    for value in array {
        buffer.write_all(&value.to_be_bytes())?;
    }
    Ok(())
}

#[cfg(test)]
mod tests {
    use insta::assert_debug_snapshot;

    use super::*;

    #[test]
    fn test_eight_byte_real_zero() {
        let value = 0.0;
        let result = eight_byte_real(value);

        assert_debug_snapshot!(result, @r"
        [
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
        ]
        ");
    }

    #[test]
    fn test_eight_byte_real_negative() {
        let value = -123.456;
        let result = eight_byte_real(value);

        assert_debug_snapshot!(result, @r"
        [
            194,
            123,
            116,
            188,
            106,
            126,
            249,
            220,
        ]
        ");
    }

    #[test]
    fn test_eight_byte_real_positive() {
        let value = 123.456;
        let result = eight_byte_real(value);

        assert_debug_snapshot!(result, @r"
        [
            66,
            123,
            116,
            188,
            106,
            126,
            249,
            220,
        ]
        ");
    }

    #[test]
    fn test_height_byte_real_log() {
        let value = 16.0;
        let result = eight_byte_real(value);

        assert_debug_snapshot!(result, @r"
        [
            66,
            16,
            0,
            0,
            0,
            0,
            0,
            0,
        ]
        ");
    }
}