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encase 0.1.1

Provides a mechanism to lay out data into GPU buffers ensuring WGSL's memory layout requirements are met
Documentation 
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use crate::core::{
    BufferMut, BufferRef, CreateFrom, Metadata, ReadFrom, Reader, Size, SizeValue, WgslType,
    WriteInto, Writer, MIN_UNIFORM_ALIGNMENT,
};

pub struct ArrayMetadata {
    pub stride: SizeValue,
    pub el_padding: u64,
}

impl Metadata<ArrayMetadata> {
    pub const fn stride(self) -> SizeValue {
        self.extra.stride
    }

    pub const fn el_padding(self) -> u64 {
        self.extra.el_padding
    }
}

impl<T: WgslType + Size, const N: usize> WgslType for [T; N] {
    type ExtraMetadata = ArrayMetadata;
    const METADATA: Metadata<Self::ExtraMetadata> = {
        let alignment = T::METADATA.alignment();
        let el_size = SizeValue::from(T::SIZE);

        let stride = alignment.round_up_size(el_size);
        let el_padding = alignment.padding_needed_for(el_size.get());

        let size = match N {
            0 => panic!("0 sized arrays are not supported!"),
            val => stride.mul(val as u64),
        };

        Metadata {
            alignment,
            min_size: size,
            extra: ArrayMetadata { stride, el_padding },
        }
    };

    const UNIFORM_COMPAT_ASSERT: () = crate::utils::consume_zsts([
        <T as WgslType>::UNIFORM_COMPAT_ASSERT,
        const_panic::concat_assert!(
            MIN_UNIFORM_ALIGNMENT.is_aligned(Self::METADATA.stride().get()),
            "array stride must be a multiple of ",
            MIN_UNIFORM_ALIGNMENT.get(),
            " (current stride: ",
            Self::METADATA.stride().get(),
            ")"
        ),
    ]);
}

impl<T: Size, const N: usize> Size for [T; N] {}

impl<T: WriteInto, const N: usize> WriteInto for [T; N]
where
    Self: WgslType<ExtraMetadata = ArrayMetadata>,
{
    fn write_into<B: BufferMut>(&self, writer: &mut Writer<B>) {
        for item in self {
            WriteInto::write_into(item, writer);
            writer.advance(Self::METADATA.el_padding() as usize);
        }
    }
}

impl<T: ReadFrom, const N: usize> ReadFrom for [T; N]
where
    Self: WgslType<ExtraMetadata = ArrayMetadata>,
{
    fn read_from<B: BufferRef>(&mut self, reader: &mut Reader<B>) {
        for elem in self {
            ReadFrom::read_from(elem, reader);
            reader.advance(Self::METADATA.el_padding() as usize);
        }
    }
}

impl<T: CreateFrom, const N: usize> CreateFrom for [T; N]
where
    Self: WgslType<ExtraMetadata = ArrayMetadata>,
{
    fn create_from<B: BufferRef>(reader: &mut Reader<B>) -> Self {
        crate::utils::ArrayExt::from_fn(|_| {
            let res = CreateFrom::create_from(reader);
            reader.advance(Self::METADATA.el_padding() as usize);
            res
        })
    }
}