wgpu/macros/
mod.rs

1//! Convenience macros
2
3#[cfg(doc)]
4use crate::{VertexAttribute, VertexBufferLayout, VertexFormat};
5
6/// Macro to produce an array of [`VertexAttribute`].
7///
8/// The input is a sequence of pairs of shader locations (expression of type [`u32`]) and
9/// variant names of [`VertexFormat`].
10///
11/// The return value has type `[VertexAttribute; N]`, where `N` is the number of inputs.
12///
13/// Offsets are calculated automatically,
14/// using the assumption that there is no padding or other data between attributes.
15///
16/// # Example
17///
18/// ```
19/// // Suppose that this is our vertex format:
20/// #[repr(C, packed)]
21/// struct Vertex {
22///     foo: [f32; 2],
23///     bar: f32,
24///     baz: [u16; 4],
25/// }
26///
27/// // Then these attributes match it:
28/// let attrs = wgpu::vertex_attr_array![
29///     0 => Float32x2,
30///     1 => Float32,
31///     2 => Uint16x4,
32/// ];
33///
34/// // Here's the full data structure the macro produced:
35/// use wgpu::{VertexAttribute as A, VertexFormat as F};
36/// assert_eq!(attrs, [
37///     A { format: F::Float32x2, offset:  0, shader_location: 0, },
38///     A { format: F::Float32,   offset:  8, shader_location: 1, },
39///     A { format: F::Uint16x4,  offset: 12, shader_location: 2, },
40/// ]);
41/// ```
42///
43/// See [`VertexBufferLayout`] for an example building on this one.
44#[macro_export]
45macro_rules! vertex_attr_array {
46    ($($location:expr => $format:ident),* $(,)?) => {
47        $crate::_vertex_attr_array_helper!([] ; 0; $($location => $format ,)*)
48    };
49}
50
51#[doc(hidden)]
52#[macro_export]
53macro_rules! _vertex_attr_array_helper {
54    ([$($t:expr,)*] ; $off:expr ;) => { [$($t,)*] };
55    ([$($t:expr,)*] ; $off:expr ; $location:expr => $format:ident, $($ll:expr => $ii:ident ,)*) => {
56        $crate::_vertex_attr_array_helper!(
57            [$($t,)*
58            $crate::VertexAttribute {
59                format: $crate::VertexFormat :: $format,
60                offset: $off,
61                shader_location: $location,
62            },];
63            $off + $crate::VertexFormat :: $format.size();
64            $($ll => $ii ,)*
65        )
66    };
67}
68
69#[test]
70fn test_vertex_attr_array() {
71    let attrs = vertex_attr_array![0 => Float32x2, 3 => Uint16x4];
72    // VertexAttribute does not support PartialEq, so we cannot test directly
73    assert_eq!(attrs.len(), 2);
74    assert_eq!(attrs[0].offset, 0);
75    assert_eq!(attrs[0].shader_location, 0);
76    assert_eq!(attrs[1].offset, size_of::<(f32, f32)>() as u64);
77    assert_eq!(attrs[1].shader_location, 3);
78}
79
80#[macro_export]
81#[doc(hidden)]
82macro_rules! include_spirv_source {
83    ($($token:tt)*) => {
84        {
85            const SPIRV_SOURCE: [
86                u8;
87                $crate::__macro_helpers::include_bytes!($($token)*).len()
88            ] = *$crate::__macro_helpers::include_bytes!($($token)*);
89            const SPIRV_LEN: usize = SPIRV_SOURCE.len() / 4;
90            const SPIRV_WORDS: [u32; SPIRV_LEN] = $crate::util::make_spirv_const(SPIRV_SOURCE);
91            &SPIRV_WORDS
92        }
93    }
94}
95
96#[test]
97fn make_spirv_le_pass() {
98    static SPIRV: &[u32] = include_spirv_source!("le-aligned.spv");
99    assert_eq!(SPIRV, &[0x07230203, 0x11223344]);
100}
101
102#[test]
103fn make_spirv_be_pass() {
104    static SPIRV: &[u32] = include_spirv_source!("be-aligned.spv");
105    assert_eq!(SPIRV, &[0x07230203, 0x11223344]);
106}
107
108/// Macro to load a SPIR-V module statically.
109///
110/// It ensures the word alignment as well as the magic number.
111///
112/// Return type: [`crate::ShaderModuleDescriptor`]
113#[macro_export]
114#[cfg(feature = "spirv")]
115macro_rules! include_spirv {
116    ($($token:tt)*) => {
117        {
118            $crate::ShaderModuleDescriptor {
119                label: Some($($token)*),
120                source: $crate::ShaderSource::SpirV(
121                    $crate::__macro_helpers::Cow::Borrowed($crate::include_spirv_source!($($token)*))
122                ),
123            }
124        }
125    };
126}
127
128#[cfg(all(feature = "spirv", test))]
129#[expect(dead_code)]
130static SPIRV: crate::ShaderModuleDescriptor<'_> = include_spirv!("le-aligned.spv");
131
132/// Macro to load raw SPIR-V data statically, for use with [`Features::EXPERIMENTAL_PASSTHROUGH_SHADERS`].
133///
134/// It ensures the word alignment as well as the magic number.
135///
136/// [`Features::EXPERIMENTAL_PASSTHROUGH_SHADERS`]: crate::Features::EXPERIMENTAL_PASSTHROUGH_SHADERS
137#[macro_export]
138macro_rules! include_spirv_raw {
139    ($($token:tt)*) => {
140        {
141            $crate::ShaderModuleDescriptorPassthrough {
142                label: $crate::__macro_helpers::Some($($token)*),
143                spirv: Some($crate::__macro_helpers::Cow::Borrowed($crate::include_spirv_source!($($token)*))),
144                // This is unused for SPIR-V
145                num_workgroups: (0, 0, 0),
146                dxil: None,
147                metallib: None,
148                msl: None,
149                hlsl: None,
150                glsl: None,
151                wgsl: None,
152            }
153        }
154    };
155}
156
157#[cfg(test)]
158#[expect(dead_code)]
159static SPIRV_RAW: crate::ShaderModuleDescriptorPassthrough<'_> =
160    include_spirv_raw!("le-aligned.spv");
161
162/// Load WGSL source code from a file at compile time.
163///
164/// The loaded path is relative to the path of the file containing the macro call, in the same way
165/// as [`include_str!`] operates.
166///
167/// ```ignore
168/// fn main() {
169///     let module: ShaderModuleDescriptor = include_wgsl!("shader.wgsl");
170/// }
171/// ```
172#[macro_export]
173macro_rules! include_wgsl {
174    ($($token:tt)*) => {
175        {
176            $crate::ShaderModuleDescriptor {
177                label: $crate::__macro_helpers::Some($($token)*),
178                source: $crate::ShaderSource::Wgsl($crate::__macro_helpers::Cow::Borrowed($crate::__macro_helpers::include_str!($($token)*))),
179            }
180        }
181    };
182}
183
184// Macros which help us generate the documentation of which hal types correspond to which backend.
185//
186// Because all backends are not compiled into the program, we cannot link to them in all situations,
187// we need to only link to the types if the backend is compiled in. These are used in #[doc] attributes
188// so cannot have more than one line, so cannot use internal cfgs.
189
190/// Helper macro to generate the documentation for dx12 hal methods, referencing the hal type.
191#[cfg(dx12)]
192macro_rules! hal_type_dx12 {
193    ($ty: literal) => {
194        concat!("- [`hal::api::Dx12`] uses [`hal::dx12::", $ty, "`]")
195    };
196}
197/// Helper macro to generate the documentation for dx12 hal methods, referencing the hal type.
198#[cfg(not(dx12))]
199macro_rules! hal_type_dx12 {
200    ($ty: literal) => {
201        concat!("- `hal::api::Dx12` uses `hal::dx12::", $ty, "`")
202    };
203}
204pub(crate) use hal_type_dx12;
205
206/// Helper macro to generate the documentation for metal hal methods, referencing the hal type.
207#[cfg(metal)]
208macro_rules! hal_type_metal {
209    ($ty: literal) => {
210        concat!("- [`hal::api::Metal`] uses [`hal::metal::", $ty, "`]")
211    };
212}
213/// Helper macro to generate the documentation for metal hal methods, referencing the hal type.
214#[cfg(not(metal))]
215macro_rules! hal_type_metal {
216    ($ty: literal) => {
217        concat!("- `hal::api::Metal` uses `hal::metal::", $ty, "`")
218    };
219}
220pub(crate) use hal_type_metal;
221
222/// Helper macro to generate the documentation for vulkan hal methods, referencing the hal type.
223#[cfg(vulkan)]
224macro_rules! hal_type_vulkan {
225    ($ty: literal) => {
226        concat!("- [`hal::api::Vulkan`] uses [`hal::vulkan::", $ty, "`]")
227    };
228}
229/// Helper macro to generate the documentation for vulkan hal methods, referencing the hal type.
230#[cfg(not(vulkan))]
231macro_rules! hal_type_vulkan {
232    ($ty: literal) => {
233        concat!("- `hal::api::Vulkan` uses `hal::vulkan::", $ty, "`")
234    };
235}
236pub(crate) use hal_type_vulkan;
237
238/// Helper macro to generate the documentation for gles hal methods, referencing the hal type.
239#[cfg(gles)]
240macro_rules! hal_type_gles {
241    ($ty: literal) => {
242        concat!("- [`hal::api::Gles`] uses [`hal::gles::", $ty, "`]")
243    };
244}
245/// Helper macro to generate the documentation for gles hal methods, referencing the hal type.
246#[cfg(not(gles))]
247macro_rules! hal_type_gles {
248    ($ty: literal) => {
249        concat!("- `hal::api::Gles` uses `hal::gles::", $ty, "`")
250    };
251}
252pub(crate) use hal_type_gles;
253
254#[doc(hidden)]
255pub mod helpers {
256    pub use alloc::{borrow::Cow, string::String};
257    pub use core::{include_bytes, include_str};
258    pub use Some;
259}
wgpu/macros/mod.rs

wgpu/macros/
mod.rs
