bevy_render/render_resource/
bind_group_entries.rs

1use bevy_utils::all_tuples_with_size;
2use wgpu::{BindGroupEntry, BindingResource};
3
4use super::{Sampler, TextureView};
5
6/// Helper for constructing bindgroups.
7///
8/// Allows constructing the descriptor's entries as:
9/// ```ignore (render_device cannot be easily accessed)
10/// render_device.create_bind_group(
11///     "my_bind_group",
12///     &my_layout,
13///     &BindGroupEntries::with_indices((
14///         (2, &my_sampler),
15///         (3, my_uniform),
16///     )),
17/// );
18/// ```
19///
20/// instead of
21///
22/// ```ignore (render_device cannot be easily accessed)
23/// render_device.create_bind_group(
24///     "my_bind_group",
25///     &my_layout,
26///     &[
27///         BindGroupEntry {
28///             binding: 2,
29///             resource: BindingResource::Sampler(&my_sampler),
30///         },
31///         BindGroupEntry {
32///             binding: 3,
33///             resource: my_uniform,
34///         },
35///     ],
36/// );
37/// ```
38///
39/// or
40///
41/// ```ignore (render_device cannot be easily accessed)
42/// render_device.create_bind_group(
43///     "my_bind_group",
44///     &my_layout,
45///     &BindGroupEntries::sequential((
46///         &my_sampler,
47///         my_uniform,
48///     )),
49/// );
50/// ```
51///
52/// instead of
53///
54/// ```ignore (render_device cannot be easily accessed)
55/// render_device.create_bind_group(
56///     "my_bind_group",
57///     &my_layout,
58///     &[
59///         BindGroupEntry {
60///             binding: 0,
61///             resource: BindingResource::Sampler(&my_sampler),
62///         },
63///         BindGroupEntry {
64///             binding: 1,
65///             resource: my_uniform,
66///         },
67///     ],
68/// );
69/// ```
70///
71/// or
72///
73/// ```ignore (render_device cannot be easily accessed)
74/// render_device.create_bind_group(
75///     "my_bind_group",
76///     &my_layout,
77///     &BindGroupEntries::single(my_uniform),
78/// );
79/// ```
80///
81/// instead of
82///
83/// ```ignore (render_device cannot be easily accessed)
84/// render_device.create_bind_group(
85///     "my_bind_group",
86///     &my_layout,
87///     &[
88///         BindGroupEntry {
89///             binding: 0,
90///             resource: my_uniform,
91///         },
92///     ],
93/// );
94/// ```
95pub struct BindGroupEntries<'b, const N: usize = 1> {
96    entries: [BindGroupEntry<'b>; N],
97}
98
99impl<'b, const N: usize> BindGroupEntries<'b, N> {
100    #[inline]
101    pub fn sequential(resources: impl IntoBindingArray<'b, N>) -> Self {
102        let mut i = 0;
103        Self {
104            entries: resources.into_array().map(|resource| {
105                let binding = i;
106                i += 1;
107                BindGroupEntry { binding, resource }
108            }),
109        }
110    }
111
112    #[inline]
113    pub fn with_indices(indexed_resources: impl IntoIndexedBindingArray<'b, N>) -> Self {
114        Self {
115            entries: indexed_resources
116                .into_array()
117                .map(|(binding, resource)| BindGroupEntry { binding, resource }),
118        }
119    }
120}
121
122impl<'b> BindGroupEntries<'b, 1> {
123    pub fn single(resource: impl IntoBinding<'b>) -> [BindGroupEntry<'b>; 1] {
124        [BindGroupEntry {
125            binding: 0,
126            resource: resource.into_binding(),
127        }]
128    }
129}
130
131impl<'b, const N: usize> core::ops::Deref for BindGroupEntries<'b, N> {
132    type Target = [BindGroupEntry<'b>];
133
134    fn deref(&self) -> &[BindGroupEntry<'b>] {
135        &self.entries
136    }
137}
138
139pub trait IntoBinding<'a> {
140    fn into_binding(self) -> BindingResource<'a>;
141}
142
143impl<'a> IntoBinding<'a> for &'a TextureView {
144    #[inline]
145    fn into_binding(self) -> BindingResource<'a> {
146        BindingResource::TextureView(self)
147    }
148}
149
150impl<'a> IntoBinding<'a> for &'a [&'a wgpu::TextureView] {
151    #[inline]
152    fn into_binding(self) -> BindingResource<'a> {
153        BindingResource::TextureViewArray(self)
154    }
155}
156
157impl<'a> IntoBinding<'a> for &'a Sampler {
158    #[inline]
159    fn into_binding(self) -> BindingResource<'a> {
160        BindingResource::Sampler(self)
161    }
162}
163
164impl<'a> IntoBinding<'a> for BindingResource<'a> {
165    #[inline]
166    fn into_binding(self) -> BindingResource<'a> {
167        self
168    }
169}
170
171impl<'a> IntoBinding<'a> for wgpu::BufferBinding<'a> {
172    #[inline]
173    fn into_binding(self) -> BindingResource<'a> {
174        BindingResource::Buffer(self)
175    }
176}
177
178pub trait IntoBindingArray<'b, const N: usize> {
179    fn into_array(self) -> [BindingResource<'b>; N];
180}
181
182macro_rules! impl_to_binding_slice {
183    ($N: expr, $(#[$meta:meta])* $(($T: ident, $I: ident)),*) => {
184        $(#[$meta])*
185        impl<'b, $($T: IntoBinding<'b>),*> IntoBindingArray<'b, $N> for ($($T,)*) {
186            #[inline]
187            fn into_array(self) -> [BindingResource<'b>; $N] {
188                let ($($I,)*) = self;
189                [$($I.into_binding(), )*]
190            }
191        }
192    }
193}
194
195all_tuples_with_size!(
196    #[doc(fake_variadic)]
197    impl_to_binding_slice,
198    1,
199    32,
200    T,
201    s
202);
203
204pub trait IntoIndexedBindingArray<'b, const N: usize> {
205    fn into_array(self) -> [(u32, BindingResource<'b>); N];
206}
207
208macro_rules! impl_to_indexed_binding_slice {
209    ($N: expr, $(($T: ident, $S: ident, $I: ident)),*) => {
210        impl<'b, $($T: IntoBinding<'b>),*> IntoIndexedBindingArray<'b, $N> for ($((u32, $T),)*) {
211            #[inline]
212            fn into_array(self) -> [(u32, BindingResource<'b>); $N] {
213                let ($(($S, $I),)*) = self;
214                [$(($S, $I.into_binding())), *]
215            }
216        }
217    }
218}
219
220all_tuples_with_size!(impl_to_indexed_binding_slice, 1, 32, T, n, s);
221
222pub struct DynamicBindGroupEntries<'b> {
223    entries: Vec<BindGroupEntry<'b>>,
224}
225
226impl<'b> DynamicBindGroupEntries<'b> {
227    pub fn sequential<const N: usize>(entries: impl IntoBindingArray<'b, N>) -> Self {
228        Self {
229            entries: entries
230                .into_array()
231                .into_iter()
232                .enumerate()
233                .map(|(ix, resource)| BindGroupEntry {
234                    binding: ix as u32,
235                    resource,
236                })
237                .collect(),
238        }
239    }
240
241    pub fn extend_sequential<const N: usize>(
242        mut self,
243        entries: impl IntoBindingArray<'b, N>,
244    ) -> Self {
245        let start = self.entries.last().unwrap().binding + 1;
246        self.entries.extend(
247            entries
248                .into_array()
249                .into_iter()
250                .enumerate()
251                .map(|(ix, resource)| BindGroupEntry {
252                    binding: start + ix as u32,
253                    resource,
254                }),
255        );
256        self
257    }
258
259    pub fn new_with_indices<const N: usize>(entries: impl IntoIndexedBindingArray<'b, N>) -> Self {
260        Self {
261            entries: entries
262                .into_array()
263                .into_iter()
264                .map(|(binding, resource)| BindGroupEntry { binding, resource })
265                .collect(),
266        }
267    }
268
269    pub fn extend_with_indices<const N: usize>(
270        mut self,
271        entries: impl IntoIndexedBindingArray<'b, N>,
272    ) -> Self {
273        self.entries.extend(
274            entries
275                .into_array()
276                .into_iter()
277                .map(|(binding, resource)| BindGroupEntry { binding, resource }),
278        );
279        self
280    }
281}
282
283impl<'b> core::ops::Deref for DynamicBindGroupEntries<'b> {
284    type Target = [BindGroupEntry<'b>];
285
286    fn deref(&self) -> &[BindGroupEntry<'b>] {
287        &self.entries
288    }
289}
bevy_render/render_resource/bind_group_entries.rs

bevy_render/render_resource/
bind_group_entries.rs
