Vertex buffers

[daxpedda]

I am currently trying to use encase with wgpu, but got a bit confused when I tried to use it for vertex buffers.

As far as I could tell, the only difference between StorageBuffer and UniformBuffer is that UniformBuffer calls assert_uniform_compat.

So if I need to make a vertex buffer, am I supposed to just use StorageBuffer? (worked fine so far by the way)

[teoxoy]

Vertex buffers are a bit tricky to fit into the current design since they have a couple more limitations but also offer more flexibility at the same time. Only scalars and vectors should be allowed and there are also 8 bit and 16 bit variants that get mapped automatically to 32 bit ones in the shader.

I experimented with adding support for them a while ago but don't have anything concrete yet.

Do note that using the existing uniform/storage buffer warpers for this might not always work since vertex buffer items are tightly packed.

[teoxoy]

I'd personally use bytemuck (for vertex buffers) for now since there is no extra padding needed for them.

[daxpedda]

Thanks for the explanation, will do.

[kaphula]

I'd personally use bytemuck (for vertex buffers) for now since there is no extra padding needed for them.

Sorry for necrobump, but is there currently a solution for index buffers? As far as I know, if you have index buffer of u16 values for example, you need to pad them correctly. Casting arbitrarily sized index array through bytemuck can fail unlike vertex buffer.

Edit: Well I scrapped something for this case and it seems to work:

pub fn pad_index_buffer(buffer: &[u16]) -> Vec<u16> {
    let s = buffer.len() % 4;
    let mut gg = buffer.to_vec();
    if s > 0 {
        for _ in 0..s {
            gg.push(0);
        }
    }
    gg
}

[teoxoy]

@kaphula &[u16] to &[u8] via bytemuck should work, the reverse might not (if the size is odd).