pebble/wgpu/
buffers.rs

1pub enum BufferSource<'a> {
2    Data(&'a [u8]),
3    Buffer(wgpu::Buffer),
4}
5
6impl<'a> From<&'a [u8]> for BufferSource<'a> {
7    fn from(data: &'a [u8]) -> Self {
8        BufferSource::Data(data)
9    }
10}
11
12impl<'a> From<wgpu::Buffer> for BufferSource<'a> {
13    fn from(buffer: wgpu::Buffer) -> Self {
14        BufferSource::Buffer(buffer)
15    }
16}
17
18pub enum BindingResource<'a> {
19    UniformBuffer(BufferSource<'a>),
20    StorageBuffer(BufferSource<'a>),
21    TextureView(&'a wgpu::TextureView),
22    Sampler(&'a wgpu::Sampler),
23}
24
25pub fn build_buffer(device: &wgpu::Device, contents: &[u8], usage: wgpu::BufferUsages) -> wgpu::Buffer {
26    use wgpu::util::DeviceExt;
27    device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
28        label: None,
29        contents,
30        usage,
31    })
32}
33
34pub fn resolve_buffer(device: &wgpu::Device, source: BufferSource<'_>, usage: wgpu::BufferUsages) -> wgpu::Buffer {
35    match source {
36        BufferSource::Data(data) => build_buffer(device, data, usage),
37        BufferSource::Buffer(buffer) => buffer,
38    }
39}
40
41pub fn resolve_uniform_buffer(device: &wgpu::Device, source: BufferSource<'_>) -> wgpu::Buffer {
42    resolve_buffer(device, source, wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST)
43}
44
45pub fn resolve_storage_buffer(device: &wgpu::Device, source: BufferSource<'_>) -> wgpu::Buffer {
46    resolve_buffer(device, source, wgpu::BufferUsages::STORAGE | wgpu::BufferUsages::COPY_DST)
47}
48
49pub fn build_uniform_bind_group<'a>(
50    device: &wgpu::Device,
51    layout: &wgpu::BindGroupLayout,
52    source: impl Into<BufferSource<'a>>,
53) -> (wgpu::Buffer, wgpu::BindGroup) {
54    let (mut buffers, bind_group) = build_bind_group(device, layout, vec![BindingResource::UniformBuffer(source.into())]);
55    (buffers.remove(0), bind_group)
56}
57
58pub fn update_uniform_buffer(queue: &wgpu::Queue, buffer: &wgpu::Buffer, data: &[u8]) {
59    queue.write_buffer(buffer, 0, data);
60}
61
62/// Builds a bind group from multiple resources. Buffers created from `Data` are returned
63/// in order (texture views and samplers are not returned). Pre-built buffers passed via
64/// `Buffer` are consumed and also returned.
65pub fn build_bind_group<'a>(
66    device: &wgpu::Device,
67    layout: &wgpu::BindGroupLayout,
68    resources: Vec<BindingResource<'a>>,
69) -> (Vec<wgpu::Buffer>, wgpu::BindGroup) {
70    enum Resolved<'a> {
71        Buffer(wgpu::Buffer),
72        TextureView(&'a wgpu::TextureView),
73        Sampler(&'a wgpu::Sampler),
74    }
75
76    let resolved: Vec<Resolved> = resources
77        .into_iter()
78        .map(|r| match r {
79            BindingResource::UniformBuffer(src) => Resolved::Buffer(resolve_uniform_buffer(device, src)),
80            BindingResource::StorageBuffer(src) => Resolved::Buffer(resolve_storage_buffer(device, src)),
81            BindingResource::TextureView(view) => Resolved::TextureView(view),
82            BindingResource::Sampler(sampler) => Resolved::Sampler(sampler),
83        })
84        .collect();
85
86    let bind_group = {
87        let entries: Vec<wgpu::BindGroupEntry> = resolved
88            .iter()
89            .enumerate()
90            .map(|(i, r)| wgpu::BindGroupEntry {
91                binding: i as u32,
92                resource: match r {
93                    Resolved::Buffer(buf) => buf.as_entire_binding(),
94                    Resolved::TextureView(view) => wgpu::BindingResource::TextureView(view),
95                    Resolved::Sampler(sampler) => wgpu::BindingResource::Sampler(sampler),
96                },
97            })
98            .collect();
99
100        device.create_bind_group(&wgpu::BindGroupDescriptor {
101            label: None,
102            layout,
103            entries: &entries,
104        })
105    };
106
107    let buffers = resolved
108        .into_iter()
109        .filter_map(|r| match r {
110            Resolved::Buffer(buf) => Some(buf),
111            _ => None,
112        })
113        .collect();
114
115    (buffers, bind_group)
116}
pebble/wgpu/buffers.rs

pebble/wgpu/
buffers.rs
