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 bytemuck::{Pod, Zeroable};
use crate::internal::max;
use crate::std140::{AsStd140, Std140};
pub struct DynamicUniform<T>(pub T);
impl<T: AsStd140> AsStd140 for DynamicUniform<T> {
type Std140Type = DynamicUniformStd140<<T as AsStd140>::Std140Type>;
fn as_std140(&self) -> Self::Std140Type {
DynamicUniformStd140(self.0.as_std140())
}
}
#[derive(Clone, Copy)]
#[repr(transparent)]
pub struct DynamicUniformStd140<T>(T);
unsafe impl<T: Std140> Std140 for DynamicUniformStd140<T> {
const ALIGNMENT: usize = max(256, T::ALIGNMENT);
}
unsafe impl<T: Zeroable> Zeroable for DynamicUniformStd140<T> {}
unsafe impl<T: Pod> Pod for DynamicUniformStd140<T> {}
#[cfg(test)]
mod test {
use super::*;
use crate::std140;
#[test]
fn size_is_unchanged() {
let dynamic_f32 = DynamicUniform(0.0f32);
assert_eq!(dynamic_f32.std140_size(), 0.0f32.std140_size());
}
#[test]
fn alignment_applies() {
let mut output = Vec::new();
let mut writer = std140::Writer::new(&mut output);
writer.write(&DynamicUniform(0.0f32)).unwrap();
assert_eq!(writer.len(), 4);
writer.write(&DynamicUniform(1.0f32)).unwrap();
assert_eq!(writer.len(), 260);
}
}