Bind group layout entries

[IceSentry]

Objective

• Follow up to Bind group entries #9694

Solution

• Same api as Bind group entries #9694 but adapted for BindGroupLayoutEntry
• Use the same ShaderStages visibilty for all entries by default
• Add BindingType helper function that mirror the wgsl equivalent and that make writing layouts much simpler.

Before:

let layout = render_device.create_bind_group_layout(&BindGroupLayoutDescriptor {
    label: Some("post_process_bind_group_layout"),
    entries: &[
        BindGroupLayoutEntry {
            binding: 0,
            visibility: ShaderStages::FRAGMENT,
            ty: BindingType::Texture {
                sample_type: TextureSampleType::Float { filterable: true },
                view_dimension: TextureViewDimension::D2,
                multisampled: false,
            },
            count: None,
        },
        BindGroupLayoutEntry {
            binding: 1,
            visibility: ShaderStages::FRAGMENT,
            ty: BindingType::Sampler(SamplerBindingType::Filtering),
            count: None,
        },
        BindGroupLayoutEntry {
            binding: 2,
            visibility: ShaderStages::FRAGMENT,
            ty: BindingType::Buffer {
                ty: bevy::render::render_resource::BufferBindingType::Uniform,
                has_dynamic_offset: false,
                min_binding_size: Some(PostProcessSettings::min_size()),
            },
            count: None,
        },
    ],
});

After:

let layout = render_device.create_bind_group_layout(
    "post_process_bind_group_layout"),
    &BindGroupLayoutEntries::sequential(
        ShaderStages::FRAGMENT,
        (
            texture_2d_f32(),
            sampler(SamplerBindingType::Filtering),
            uniform_buffer(false, Some(PostProcessSettings::min_size())),
        ),
    ),
);

Here's a more extreme example in bevy_solari: JMS55@86dab7f

---

Changelog

• Added BindGroupLayoutEntries and all BindingType helper functions.

Migration Guide

RenderDevice::create_bind_group_layout() doesn't take a BindGroupLayoutDescriptor anymore. You need to provide the parameters separately

// 0.12
let layout = render_device.create_bind_group_layout(&BindGroupLayoutDescriptor {
    label: Some("post_process_bind_group_layout"),
    entries: &[
        BindGroupLayoutEntry {
			// ...
        },
    ],
});

// 0.13
let layout = render_device.create_bind_group_layout(
	"post_process_bind_group_layout",
    &[
        BindGroupLayoutEntry {
			// ...
        },
    ],
);

TODO

• implement a Dynamic variant
• update the RenderDevice::create_bind_group_layout() api to match the one from RenderDevice::creat_bind_group()
• docs

[JMS55]

Small typos: *_mutlisampled -> *_multisampled

Otherwise lgtm, so pre-emptivley leaving my approval.

[IceSentry]

Fixed the typo + fixed ci + rebased

[IceSentry]

We might want to wait after 0.12.1 to merge this

[robtfm]

nice.

the tradeoff in what to make explicit functions for, vs arguments to a generic fn is a bit tricky. i definitely think you've done the right thing by making generic functions and more specific variants as well. if anything i'd say we could go even further (sampler_filtering(), texture_storage_2d_readonly() etc), but that's definitely subjective/stylistic and i would understand if others disagree.