wgpu/
macros.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 => $ii ,)*
65        )
66    };
67}
68
69#[test]
70fn test_vertex_attr_array() {
71    let attrs = vertex_attr_array![0 => Float32x2, 3 => Uint16x4];
72    // VertexAttribute does not support PartialEq, so we cannot test directly
73    assert_eq!(attrs.len(), 2);
74    assert_eq!(attrs[0].offset, 0);
75    assert_eq!(attrs[0].shader_location, 0);
76    assert_eq!(attrs[1].offset, size_of::<(f32, f32)>() as u64);
77    assert_eq!(attrs[1].shader_location, 3);
78}
79
80/// Macro to load a SPIR-V module statically.
81///
82/// It ensures the word alignment as well as the magic number.
83///
84/// Return type: [`crate::ShaderModuleDescriptor`]
85#[macro_export]
86#[cfg(feature = "spirv")]
87macro_rules! include_spirv {
88    ($($token:tt)*) => {
89        {
90            //log::info!("including '{}'", $($token)*);
91            $crate::ShaderModuleDescriptor {
92                label: Some($($token)*),
93                source: $crate::util::make_spirv(include_bytes!($($token)*)),
94            }
95        }
96    };
97}
98
99/// Macro to load raw SPIR-V data statically, for use with [`Features::EXPERIMENTAL_PASSTHROUGH_SHADERS`].
100///
101/// It ensures the word alignment as well as the magic number.
102///
103/// [`Features::EXPERIMENTAL_PASSTHROUGH_SHADERS`]: crate::Features::EXPERIMENTAL_PASSTHROUGH_SHADERS
104#[macro_export]
105macro_rules! include_spirv_raw {
106    ($($token:tt)*) => {
107        {
108            //log::info!("including '{}'", $($token)*);
109            $crate::ShaderModuleDescriptorPassthrough {
110                label: $crate::__macro_helpers::Some($($token)*),
111                spirv: Some($crate::util::make_spirv_raw($crate::__macro_helpers::include_bytes!($($token)*))),
112
113                entry_point: "".to_owned(),
114                // This is unused for SPIR-V
115                num_workgroups: (0, 0, 0),
116                reflection: None,
117                shader_runtime_checks: $crate::ShaderRuntimeChecks::unchecked(),
118                dxil: None,
119                msl: None,
120                hlsl: None,
121                glsl: None,
122                wgsl: None,
123            }
124        }
125    };
126}
127
128/// Load WGSL source code from a file at compile time.
129///
130/// The loaded path is relative to the path of the file containing the macro call, in the same way
131/// as [`include_str!`] operates.
132///
133/// ```ignore
134/// fn main() {
135///     let module: ShaderModuleDescriptor = include_wgsl!("shader.wgsl");
136/// }
137/// ```
138#[macro_export]
139macro_rules! include_wgsl {
140    ($($token:tt)*) => {
141        {
142            //log::info!("including '{}'", $($token)*);
143            $crate::ShaderModuleDescriptor {
144                label: $crate::__macro_helpers::Some($($token)*),
145                source: $crate::ShaderSource::Wgsl($crate::__macro_helpers::Cow::Borrowed($crate::__macro_helpers::include_str!($($token)*))),
146            }
147        }
148    };
149}
150
151// Macros which help us generate the documentation of which hal types correspond to which backend.
152//
153// Because all backends are not compiled into the program, we cannot link to them in all situations,
154// we need to only link to the types if the backend is compiled in. These are used in #[doc] attributes
155// so cannot have more than one line, so cannot use internal cfgs.
156
157/// Helper macro to generate the documentation for dx12 hal methods, referencing the hal type.
158#[macro_export]
159#[doc(hidden)]
160#[cfg(dx12)]
161macro_rules! hal_type_dx12 {
162    ($ty: literal) => {
163        concat!("- [`hal::api::Dx12`] uses [`hal::dx12::", $ty, "`]")
164    };
165}
166/// Helper macro to generate the documentation for dx12 hal methods, referencing the hal type.
167#[macro_export]
168#[doc(hidden)]
169#[cfg(not(dx12))]
170macro_rules! hal_type_dx12 {
171    ($ty: literal) => {
172        concat!("- `hal::api::Dx12` uses `hal::dx12::", $ty, "`")
173    };
174}
175
176/// Helper macro to generate the documentation for metal hal methods, referencing the hal type.
177#[macro_export]
178#[doc(hidden)]
179#[cfg(metal)]
180macro_rules! hal_type_metal {
181    ($ty: literal) => {
182        concat!("- [`hal::api::Metal`] uses [`hal::metal::", $ty, "`]")
183    };
184}
185/// Helper macro to generate the documentation for metal hal methods, referencing the hal type.
186#[macro_export]
187#[doc(hidden)]
188#[cfg(not(metal))]
189macro_rules! hal_type_metal {
190    ($ty: literal) => {
191        concat!("- `hal::api::Metal` uses `hal::metal::", $ty, "`")
192    };
193}
194
195/// Helper macro to generate the documentation for vulkan hal methods, referencing the hal type.
196#[macro_export]
197#[doc(hidden)]
198#[cfg(vulkan)]
199macro_rules! hal_type_vulkan {
200    ($ty: literal) => {
201        concat!("- [`hal::api::Vulkan`] uses [`hal::vulkan::", $ty, "`]")
202    };
203}
204/// Helper macro to generate the documentation for vulkan hal methods, referencing the hal type.
205#[macro_export]
206#[doc(hidden)]
207#[cfg(not(vulkan))]
208macro_rules! hal_type_vulkan {
209    ($ty: literal) => {
210        concat!("- `hal::api::Vulkan` uses `hal::vulkan::", $ty, "`")
211    };
212}
213
214/// Helper macro to generate the documentation for gles hal methods, referencing the hal type.
215#[macro_export]
216#[doc(hidden)]
217#[cfg(gles)]
218macro_rules! hal_type_gles {
219    ($ty: literal) => {
220        concat!("- [`hal::api::Gles`] uses [`hal::gles::", $ty, "`]")
221    };
222}
223/// Helper macro to generate the documentation for gles hal methods, referencing the hal type.
224#[macro_export]
225#[doc(hidden)]
226#[cfg(not(gles))]
227macro_rules! hal_type_gles {
228    ($ty: literal) => {
229        concat!("- `hal::api::Gles` uses `hal::gles::", $ty, "`")
230    };
231}
232
233#[doc(hidden)]
234pub mod helpers {
235    pub use alloc::borrow::Cow;
236    pub use core::{include_bytes, include_str};
237    pub use Some;
238}
wgpu/macros.rs

wgpu/
macros.rs
