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
use core::ops::{Div, Mul, Neg, Sub};
use num_traits::{One, Zero};
use super::set_identity;
#[inline]
pub fn inv<'out, T>(out: &'out mut [T; 6], m: &[T; 6]) -> &'out mut [T; 6]
where
T: One + Zero + Sub<T, Output = T>,
for<'a, 'b> &'a T: Neg<Output = T> + Mul<&'b T, Output = T> + Div<&'b T, Output = T>,
{
let m11 = &m[0];
let m12 = &m[2];
let m13 = &m[4];
let m21 = &m[1];
let m22 = &m[3];
let m23 = &m[5];
let d = m11 * m22 - m12 * m21;
if d.is_zero() {
set_identity(out)
} else {
let inv_d = &T::one() / &d;
out[0] = m22 * &inv_d;
out[1] = &-m12 * &inv_d;
out[2] = &-m21 * &inv_d;
out[3] = m11 * &inv_d;
out[4] = &(m21 * m23 - m22 * m13) * &inv_d;
out[5] = &-&(m11 * m23 - m12 * m13) * &inv_d;
out
}
}
#[inline]
pub fn inv_mut<'out, T>(out: &'out mut [T; 6]) -> &'out mut [T; 6]
where
T: Clone + One + Zero + Sub<T, Output = T>,
for<'a, 'b> &'a T: Neg<Output = T> + Mul<&'b T, Output = T> + Div<&'b T, Output = T>,
{
let tmp = out.clone();
inv(out, &tmp)
}