wgpu/
dispatch.rs

1//! Infrastructure for dispatching calls to the appropriate "backend". The "backends" are:
2//!
3//! - `wgpu_core`: An implementation of the the wgpu api on top of various native graphics APIs.
4//! - `webgpu`: An implementation of the wgpu api which calls WebGPU directly.
5//!
6//! The interface traits are all object safe and listed in the `InterfaceTypes` trait.
7//!
8//! The method for dispatching should optimize well if only one backend is
9//! compiled in, as-if there was no dispatching at all. See the comments on
10//! [`dispatch_types`] for details.
11//!
12//! [`dispatch_types`]: macro.dispatch_types.html
13
14#![allow(
15    drop_bounds,
16    reason = "This exists to remind implementors to impl drop."
17)]
18#![allow(clippy::too_many_arguments, reason = "It's fine.")]
19#![allow(
20    missing_docs,
21    clippy::missing_safety_doc,
22    reason = "Interfaces are not documented"
23)]
24#![allow(
25    clippy::len_without_is_empty,
26    reason = "trait is minimal, not ergonomic"
27)]
28
29use crate::{Blas, Tlas, WasmNotSend, WasmNotSendSync, WriteOnly};
30
31use alloc::{boxed::Box, string::String, sync::Arc, vec::Vec};
32use core::{any::Any, fmt::Debug, future::Future, hash::Hash, ops::Range, pin::Pin};
33
34#[cfg(custom)]
35use crate::backend::custom::*;
36#[cfg(webgpu)]
37use crate::backend::webgpu::*;
38#[cfg(wgpu_core)]
39use crate::backend::wgpu_core::*;
40
41/// Create a single trait with the given supertraits and a blanket impl for all types that implement them.
42///
43/// This is useful for creating a trait alias as a shorthand.
44macro_rules! trait_alias {
45    ($name:ident: $($bound:tt)+) => {
46        pub trait $name: $($bound)+ {}
47        impl<T: $($bound)+> $name for T {}
48    };
49}
50
51// Various return futures in the API.
52trait_alias!(RequestAdapterFuture: Future<Output = Result<DispatchAdapter, wgt::RequestAdapterError>> + WasmNotSend + 'static);
53trait_alias!(RequestDeviceFuture: Future<Output = Result<(DispatchDevice, DispatchQueue), crate::RequestDeviceError>> + WasmNotSend + 'static);
54trait_alias!(PopErrorScopeFuture: Future<Output = Option<crate::Error>> + WasmNotSend + 'static);
55trait_alias!(ShaderCompilationInfoFuture: Future<Output = crate::CompilationInfo> + WasmNotSend + 'static);
56trait_alias!(EnumerateAdapterFuture: Future<Output = Vec<DispatchAdapter>> + WasmNotSend + 'static);
57
58// We can't use trait aliases here, as you can't convert from a dyn Trait to dyn Supertrait _yet_.
59#[cfg(send_sync)]
60pub type BoxDeviceLostCallback = Box<dyn FnOnce(crate::DeviceLostReason, String) + Send + 'static>;
61#[cfg(not(send_sync))]
62pub type BoxDeviceLostCallback = Box<dyn FnOnce(crate::DeviceLostReason, String) + 'static>;
63#[cfg(send_sync)]
64pub type BoxSubmittedWorkDoneCallback = Box<dyn FnOnce() + Send + 'static>;
65#[cfg(not(send_sync))]
66pub type BoxSubmittedWorkDoneCallback = Box<dyn FnOnce() + 'static>;
67#[cfg(send_sync)]
68pub type BufferMapCallback = Box<dyn FnOnce(Result<(), crate::BufferAsyncError>) + Send + 'static>;
69#[cfg(not(send_sync))]
70pub type BufferMapCallback = Box<dyn FnOnce(Result<(), crate::BufferAsyncError>) + 'static>;
71
72#[cfg(send_sync)]
73pub type BlasCompactCallback = Box<dyn FnOnce(Result<(), crate::BlasAsyncError>) + Send + 'static>;
74#[cfg(not(send_sync))]
75pub type BlasCompactCallback = Box<dyn FnOnce(Result<(), crate::BlasAsyncError>) + 'static>;
76
77// remove when rust 1.86
78#[cfg_attr(not(custom), expect(dead_code))]
79pub trait AsAny {
80    fn as_any(&self) -> &dyn Any;
81}
82
83impl<T: 'static> AsAny for T {
84    fn as_any(&self) -> &dyn Any {
85        self
86    }
87}
88
89// Common traits on all the interface traits
90trait_alias!(CommonTraits: AsAny + Any + Debug + WasmNotSendSync);
91
92pub trait InstanceInterface: CommonTraits {
93    fn new(desc: crate::InstanceDescriptor) -> Self
94    where
95        Self: Sized;
96
97    unsafe fn create_surface(
98        &self,
99        target: crate::SurfaceTargetUnsafe,
100    ) -> Result<DispatchSurface, crate::CreateSurfaceError>;
101
102    fn request_adapter(
103        &self,
104        options: &crate::RequestAdapterOptions<'_, '_>,
105    ) -> Pin<Box<dyn RequestAdapterFuture>>;
106
107    fn poll_all_devices(&self, force_wait: bool) -> bool;
108
109    #[cfg(feature = "wgsl")]
110    fn wgsl_language_features(&self) -> crate::WgslLanguageFeatures;
111
112    fn enumerate_adapters(&self, backends: crate::Backends)
113        -> Pin<Box<dyn EnumerateAdapterFuture>>;
114}
115
116pub trait AdapterInterface: CommonTraits {
117    fn request_device(
118        &self,
119        desc: &crate::DeviceDescriptor<'_>,
120    ) -> Pin<Box<dyn RequestDeviceFuture>>;
121
122    fn is_surface_supported(&self, surface: &DispatchSurface) -> bool;
123
124    fn features(&self) -> crate::Features;
125
126    fn limits(&self) -> crate::Limits;
127
128    fn downlevel_capabilities(&self) -> crate::DownlevelCapabilities;
129
130    fn get_info(&self) -> crate::AdapterInfo;
131
132    fn get_texture_format_features(
133        &self,
134        format: crate::TextureFormat,
135    ) -> crate::TextureFormatFeatures;
136
137    fn get_presentation_timestamp(&self) -> crate::PresentationTimestamp;
138
139    fn cooperative_matrix_properties(&self) -> Vec<crate::wgt::CooperativeMatrixProperties>;
140}
141
142pub trait DeviceInterface: CommonTraits {
143    fn features(&self) -> crate::Features;
144    fn limits(&self) -> crate::Limits;
145    fn adapter_info(&self) -> crate::AdapterInfo;
146
147    fn create_shader_module(
148        &self,
149        desc: crate::ShaderModuleDescriptor<'_>,
150        shader_bound_checks: crate::ShaderRuntimeChecks,
151    ) -> DispatchShaderModule;
152
153    unsafe fn create_shader_module_passthrough(
154        &self,
155        desc: &crate::ShaderModuleDescriptorPassthrough<'_>,
156    ) -> DispatchShaderModule;
157
158    fn create_bind_group_layout(
159        &self,
160        desc: &crate::BindGroupLayoutDescriptor<'_>,
161    ) -> DispatchBindGroupLayout;
162    fn create_bind_group(&self, desc: &crate::BindGroupDescriptor<'_>) -> DispatchBindGroup;
163    fn create_pipeline_layout(
164        &self,
165        desc: &crate::PipelineLayoutDescriptor<'_>,
166    ) -> DispatchPipelineLayout;
167    fn create_render_pipeline(
168        &self,
169        desc: &crate::RenderPipelineDescriptor<'_>,
170    ) -> DispatchRenderPipeline;
171    fn create_mesh_pipeline(
172        &self,
173        desc: &crate::MeshPipelineDescriptor<'_>,
174    ) -> DispatchRenderPipeline;
175    fn create_compute_pipeline(
176        &self,
177        desc: &crate::ComputePipelineDescriptor<'_>,
178    ) -> DispatchComputePipeline;
179    unsafe fn create_pipeline_cache(
180        &self,
181        desc: &crate::PipelineCacheDescriptor<'_>,
182    ) -> DispatchPipelineCache;
183    fn create_buffer(&self, desc: &crate::BufferDescriptor<'_>) -> DispatchBuffer;
184    fn create_texture(&self, desc: &crate::TextureDescriptor<'_>) -> DispatchTexture;
185    fn create_external_texture(
186        &self,
187        desc: &crate::ExternalTextureDescriptor<'_>,
188        planes: &[&crate::TextureView],
189    ) -> DispatchExternalTexture;
190    fn create_blas(
191        &self,
192        desc: &crate::CreateBlasDescriptor<'_>,
193        sizes: crate::BlasGeometrySizeDescriptors,
194    ) -> (Option<u64>, DispatchBlas);
195    fn create_tlas(&self, desc: &crate::CreateTlasDescriptor<'_>) -> DispatchTlas;
196    fn create_sampler(&self, desc: &crate::SamplerDescriptor<'_>) -> DispatchSampler;
197    fn create_query_set(&self, desc: &crate::QuerySetDescriptor<'_>) -> DispatchQuerySet;
198    fn create_command_encoder(
199        &self,
200        desc: &crate::CommandEncoderDescriptor<'_>,
201    ) -> DispatchCommandEncoder;
202    fn create_render_bundle_encoder(
203        &self,
204        desc: &crate::RenderBundleEncoderDescriptor<'_>,
205    ) -> DispatchRenderBundleEncoder;
206
207    fn set_device_lost_callback(&self, device_lost_callback: BoxDeviceLostCallback);
208
209    fn on_uncaptured_error(&self, handler: Arc<dyn crate::UncapturedErrorHandler>);
210    // Returns index on the stack of the pushed error scope.
211    fn push_error_scope(&self, filter: crate::ErrorFilter) -> u32;
212    fn pop_error_scope(&self, index: u32) -> Pin<Box<dyn PopErrorScopeFuture>>;
213
214    unsafe fn start_graphics_debugger_capture(&self);
215    unsafe fn stop_graphics_debugger_capture(&self);
216
217    fn poll(&self, poll_type: wgt::PollType<u64>) -> Result<crate::PollStatus, crate::PollError>;
218
219    fn get_internal_counters(&self) -> crate::InternalCounters;
220    fn generate_allocator_report(&self) -> Option<crate::AllocatorReport>;
221
222    fn destroy(&self);
223}
224
225pub trait QueueInterface: CommonTraits {
226    fn write_buffer(&self, buffer: &DispatchBuffer, offset: crate::BufferAddress, data: &[u8]);
227
228    fn create_staging_buffer(&self, size: crate::BufferSize) -> Option<DispatchQueueWriteBuffer>;
229    fn validate_write_buffer(
230        &self,
231        buffer: &DispatchBuffer,
232        offset: crate::BufferAddress,
233        size: crate::BufferSize,
234    ) -> Option<()>;
235    fn write_staging_buffer(
236        &self,
237        buffer: &DispatchBuffer,
238        offset: crate::BufferAddress,
239        staging_buffer: &DispatchQueueWriteBuffer,
240    );
241
242    fn write_texture(
243        &self,
244        texture: crate::TexelCopyTextureInfo<'_>,
245        data: &[u8],
246        data_layout: crate::TexelCopyBufferLayout,
247        size: crate::Extent3d,
248    );
249    #[cfg(web)]
250    fn copy_external_image_to_texture(
251        &self,
252        source: &crate::CopyExternalImageSourceInfo,
253        dest: crate::CopyExternalImageDestInfo<&crate::api::Texture>,
254        size: crate::Extent3d,
255    );
256
257    /// Submit must always drain the iterator, even in the case of error.
258    fn submit(&self, command_buffers: &mut dyn Iterator<Item = DispatchCommandBuffer>) -> u64;
259
260    fn get_timestamp_period(&self) -> f32;
261    fn on_submitted_work_done(&self, callback: BoxSubmittedWorkDoneCallback);
262
263    fn compact_blas(&self, blas: &DispatchBlas) -> (Option<u64>, DispatchBlas);
264
265    fn present(&self, detail: &DispatchSurfaceOutputDetail);
266}
267
268pub trait ShaderModuleInterface: CommonTraits {
269    fn get_compilation_info(&self) -> Pin<Box<dyn ShaderCompilationInfoFuture>>;
270}
271pub trait BindGroupLayoutInterface: CommonTraits {}
272pub trait BindGroupInterface: CommonTraits {}
273pub trait TextureViewInterface: CommonTraits {}
274pub trait SamplerInterface: CommonTraits {}
275pub trait BufferInterface: CommonTraits {
276    fn map_async(
277        &self,
278        mode: crate::MapMode,
279        range: Range<crate::BufferAddress>,
280        callback: BufferMapCallback,
281    );
282    fn get_mapped_range(
283        &self,
284        sub_range: Range<crate::BufferAddress>,
285    ) -> Result<DispatchBufferMappedRange, crate::MapRangeError>;
286
287    fn unmap(&self);
288
289    fn destroy(&self);
290}
291pub trait TextureInterface: CommonTraits {
292    fn create_view(&self, desc: &crate::TextureViewDescriptor<'_>) -> DispatchTextureView;
293
294    fn destroy(&self);
295}
296pub trait ExternalTextureInterface: CommonTraits {
297    fn destroy(&self);
298}
299pub trait BlasInterface: CommonTraits {
300    fn prepare_compact_async(&self, callback: BlasCompactCallback);
301    fn ready_for_compaction(&self) -> bool;
302}
303pub trait TlasInterface: CommonTraits {}
304pub trait QuerySetInterface: CommonTraits {}
305pub trait PipelineLayoutInterface: CommonTraits {}
306pub trait RenderPipelineInterface: CommonTraits {
307    fn get_bind_group_layout(&self, index: u32) -> DispatchBindGroupLayout;
308}
309pub trait ComputePipelineInterface: CommonTraits {
310    fn get_bind_group_layout(&self, index: u32) -> DispatchBindGroupLayout;
311}
312pub trait PipelineCacheInterface: CommonTraits {
313    fn get_data(&self) -> Option<Vec<u8>>;
314}
315pub trait CommandEncoderInterface: CommonTraits {
316    fn copy_buffer_to_buffer(
317        &self,
318        source: &DispatchBuffer,
319        source_offset: crate::BufferAddress,
320        destination: &DispatchBuffer,
321        destination_offset: crate::BufferAddress,
322        copy_size: Option<crate::BufferAddress>,
323    );
324    fn copy_buffer_to_texture(
325        &self,
326        source: crate::TexelCopyBufferInfo<'_>,
327        destination: crate::TexelCopyTextureInfo<'_>,
328        copy_size: crate::Extent3d,
329    );
330    fn copy_texture_to_buffer(
331        &self,
332        source: crate::TexelCopyTextureInfo<'_>,
333        destination: crate::TexelCopyBufferInfo<'_>,
334        copy_size: crate::Extent3d,
335    );
336    fn copy_texture_to_texture(
337        &self,
338        source: crate::TexelCopyTextureInfo<'_>,
339        destination: crate::TexelCopyTextureInfo<'_>,
340        copy_size: crate::Extent3d,
341    );
342
343    fn begin_compute_pass(&self, desc: &crate::ComputePassDescriptor<'_>) -> DispatchComputePass;
344    fn begin_render_pass(&self, desc: &crate::RenderPassDescriptor<'_>) -> DispatchRenderPass;
345    fn finish(&mut self) -> DispatchCommandBuffer;
346
347    fn clear_texture(
348        &self,
349        texture: &DispatchTexture,
350        subresource_range: &crate::ImageSubresourceRange,
351    );
352    fn clear_buffer(
353        &self,
354        buffer: &DispatchBuffer,
355        offset: crate::BufferAddress,
356        size: Option<crate::BufferAddress>,
357    );
358
359    fn insert_debug_marker(&self, label: &str);
360    fn push_debug_group(&self, label: &str);
361    fn pop_debug_group(&self);
362
363    fn write_timestamp(&self, query_set: &DispatchQuerySet, query_index: u32);
364    fn resolve_query_set(
365        &self,
366        query_set: &DispatchQuerySet,
367        first_query: u32,
368        query_count: u32,
369        destination: &DispatchBuffer,
370        destination_offset: crate::BufferAddress,
371    );
372    fn mark_acceleration_structures_built<'a>(
373        &self,
374        blas: &mut dyn Iterator<Item = &'a Blas>,
375        tlas: &mut dyn Iterator<Item = &'a Tlas>,
376    );
377
378    fn build_acceleration_structures<'a>(
379        &self,
380        blas: &mut dyn Iterator<Item = &'a crate::BlasBuildEntry<'a>>,
381        tlas: &mut dyn Iterator<Item = &'a crate::Tlas>,
382    );
383
384    fn transition_resources<'a>(
385        &mut self,
386        buffer_transitions: &mut dyn Iterator<Item = wgt::BufferTransition<&'a DispatchBuffer>>,
387        texture_transitions: &mut dyn Iterator<Item = wgt::TextureTransition<&'a DispatchTexture>>,
388    );
389}
390pub trait ComputePassInterface: CommonTraits + Drop {
391    fn set_pipeline(&mut self, pipeline: &DispatchComputePipeline);
392    fn set_bind_group(
393        &mut self,
394        index: u32,
395        bind_group: Option<&DispatchBindGroup>,
396        offsets: &[crate::DynamicOffset],
397    );
398    fn set_immediates(&mut self, offset: u32, data: &[u8]);
399
400    fn insert_debug_marker(&mut self, label: &str);
401    fn push_debug_group(&mut self, group_label: &str);
402    fn pop_debug_group(&mut self);
403
404    fn write_timestamp(&mut self, query_set: &DispatchQuerySet, query_index: u32);
405    fn begin_pipeline_statistics_query(&mut self, query_set: &DispatchQuerySet, query_index: u32);
406    fn end_pipeline_statistics_query(&mut self);
407
408    fn dispatch_workgroups(&mut self, x: u32, y: u32, z: u32);
409    fn dispatch_workgroups_indirect(
410        &mut self,
411        indirect_buffer: &DispatchBuffer,
412        indirect_offset: crate::BufferAddress,
413    );
414
415    fn transition_resources<'a>(
416        &mut self,
417        buffer_transitions: &mut dyn Iterator<Item = wgt::BufferTransition<&'a DispatchBuffer>>,
418        texture_transitions: &mut dyn Iterator<
419            Item = wgt::TextureTransition<&'a DispatchTextureView>,
420        >,
421    );
422}
423pub trait RenderPassInterface: CommonTraits + Drop {
424    fn set_pipeline(&mut self, pipeline: &DispatchRenderPipeline);
425    fn set_bind_group(
426        &mut self,
427        index: u32,
428        bind_group: Option<&DispatchBindGroup>,
429        offsets: &[crate::DynamicOffset],
430    );
431    fn set_index_buffer(
432        &mut self,
433        buffer: &DispatchBuffer,
434        index_format: crate::IndexFormat,
435        offset: crate::BufferAddress,
436        size: Option<crate::BufferSize>,
437    );
438    fn set_vertex_buffer(
439        &mut self,
440        slot: u32,
441        buffer: &DispatchBuffer,
442        offset: crate::BufferAddress,
443        size: Option<crate::BufferSize>,
444    );
445    fn set_immediates(&mut self, offset: u32, data: &[u8]);
446    fn set_blend_constant(&mut self, color: crate::Color);
447    fn set_scissor_rect(&mut self, x: u32, y: u32, width: u32, height: u32);
448    fn set_viewport(
449        &mut self,
450        x: f32,
451        y: f32,
452        width: f32,
453        height: f32,
454        min_depth: f32,
455        max_depth: f32,
456    );
457    fn set_stencil_reference(&mut self, reference: u32);
458
459    fn draw(&mut self, vertices: Range<u32>, instances: Range<u32>);
460    fn draw_indexed(&mut self, indices: Range<u32>, base_vertex: i32, instances: Range<u32>);
461    fn draw_mesh_tasks(&mut self, group_count_x: u32, group_count_y: u32, group_count_z: u32);
462    fn draw_indirect(
463        &mut self,
464        indirect_buffer: &DispatchBuffer,
465        indirect_offset: crate::BufferAddress,
466    );
467    fn draw_indexed_indirect(
468        &mut self,
469        indirect_buffer: &DispatchBuffer,
470        indirect_offset: crate::BufferAddress,
471    );
472    fn draw_mesh_tasks_indirect(
473        &mut self,
474        indirect_buffer: &DispatchBuffer,
475        indirect_offset: crate::BufferAddress,
476    );
477
478    fn multi_draw_indirect(
479        &mut self,
480        indirect_buffer: &DispatchBuffer,
481        indirect_offset: crate::BufferAddress,
482        count: u32,
483    );
484    fn multi_draw_indexed_indirect(
485        &mut self,
486        indirect_buffer: &DispatchBuffer,
487        indirect_offset: crate::BufferAddress,
488        count: u32,
489    );
490    fn multi_draw_indirect_count(
491        &mut self,
492        indirect_buffer: &DispatchBuffer,
493        indirect_offset: crate::BufferAddress,
494        count_buffer: &DispatchBuffer,
495        count_buffer_offset: crate::BufferAddress,
496        max_count: u32,
497    );
498    fn multi_draw_mesh_tasks_indirect(
499        &mut self,
500        indirect_buffer: &DispatchBuffer,
501        indirect_offset: crate::BufferAddress,
502        count: u32,
503    );
504    fn multi_draw_indexed_indirect_count(
505        &mut self,
506        indirect_buffer: &DispatchBuffer,
507        indirect_offset: crate::BufferAddress,
508        count_buffer: &DispatchBuffer,
509        count_buffer_offset: crate::BufferAddress,
510        max_count: u32,
511    );
512    fn multi_draw_mesh_tasks_indirect_count(
513        &mut self,
514        indirect_buffer: &DispatchBuffer,
515        indirect_offset: crate::BufferAddress,
516        count_buffer: &DispatchBuffer,
517        count_buffer_offset: crate::BufferAddress,
518        max_count: u32,
519    );
520
521    fn insert_debug_marker(&mut self, label: &str);
522    fn push_debug_group(&mut self, group_label: &str);
523    fn pop_debug_group(&mut self);
524
525    fn write_timestamp(&mut self, query_set: &DispatchQuerySet, query_index: u32);
526    fn begin_occlusion_query(&mut self, query_index: u32);
527    fn end_occlusion_query(&mut self);
528    fn begin_pipeline_statistics_query(&mut self, query_set: &DispatchQuerySet, query_index: u32);
529    fn end_pipeline_statistics_query(&mut self);
530
531    fn execute_bundles(&mut self, render_bundles: &mut dyn Iterator<Item = &DispatchRenderBundle>);
532}
533
534pub trait RenderBundleEncoderInterface: CommonTraits {
535    fn set_pipeline(&mut self, pipeline: &DispatchRenderPipeline);
536    fn set_bind_group(
537        &mut self,
538        index: u32,
539        bind_group: Option<&DispatchBindGroup>,
540        offsets: &[crate::DynamicOffset],
541    );
542    fn set_index_buffer(
543        &mut self,
544        buffer: &DispatchBuffer,
545        index_format: crate::IndexFormat,
546        offset: crate::BufferAddress,
547        size: Option<crate::BufferSize>,
548    );
549    fn set_vertex_buffer(
550        &mut self,
551        slot: u32,
552        buffer: &DispatchBuffer,
553        offset: crate::BufferAddress,
554        size: Option<crate::BufferSize>,
555    );
556    fn set_immediates(&mut self, offset: u32, data: &[u8]);
557
558    fn draw(&mut self, vertices: Range<u32>, instances: Range<u32>);
559    fn draw_indexed(&mut self, indices: Range<u32>, base_vertex: i32, instances: Range<u32>);
560    fn draw_indirect(
561        &mut self,
562        indirect_buffer: &DispatchBuffer,
563        indirect_offset: crate::BufferAddress,
564    );
565    fn draw_indexed_indirect(
566        &mut self,
567        indirect_buffer: &DispatchBuffer,
568        indirect_offset: crate::BufferAddress,
569    );
570
571    fn finish(self, desc: &crate::RenderBundleDescriptor<'_>) -> DispatchRenderBundle
572    where
573        Self: Sized;
574}
575
576pub trait CommandBufferInterface: CommonTraits {}
577pub trait RenderBundleInterface: CommonTraits {}
578
579pub trait SurfaceInterface: CommonTraits {
580    fn get_capabilities(&self, adapter: &DispatchAdapter) -> crate::SurfaceCapabilities;
581
582    fn configure(&self, device: &DispatchDevice, config: &crate::SurfaceConfiguration);
583    fn get_current_texture(
584        &self,
585    ) -> (
586        Option<DispatchTexture>,
587        crate::SurfaceStatus,
588        DispatchSurfaceOutputDetail,
589    );
590}
591
592pub trait SurfaceOutputDetailInterface: CommonTraits {
593    fn texture_discard(&self);
594}
595
596pub trait QueueWriteBufferInterface: CommonTraits {
597    fn len(&self) -> usize;
598
599    /// # Safety
600    ///
601    /// Must only be used on write, not read, mappings.
602    unsafe fn write_slice(&mut self) -> WriteOnly<'_, [u8]>;
603}
604
605pub trait BufferMappedRangeInterface: CommonTraits {
606    fn len(&self) -> usize;
607
608    /// # Safety
609    ///
610    /// Must only be used on read, not write, mappings.
611    unsafe fn read_slice(&self) -> &[u8];
612
613    /// # Safety
614    ///
615    /// Must only be used on write, not read, mappings.
616    unsafe fn write_slice(&mut self) -> WriteOnly<'_, [u8]>;
617
618    #[cfg(webgpu)]
619    fn as_uint8array(&self) -> &js_sys::Uint8Array;
620}
621
622/// Generates a dispatch type for some `wgpu` API type.
623///
624/// Invocations of this macro take one of the following forms:
625///
626/// ```ignore
627/// dispatch_types! {mut type D: I = Core, Web, Dyn }
628/// dispatch_types! {ref type D: I = Core, Web, Dyn }
629/// ```
630///
631/// This defines `D` as a type that dereferences to a `dyn I` trait object. Most uses of
632/// `D` in the rest of this crate just call the methods from the `dyn I` object, not from
633/// `D` itself.
634///
635/// Internally, `D` is an enum with up to three variants holding values of type `Core`,
636/// `Web`, and `Dyn`, all of which must implement `I`. `Core`, `Web` and `Dyn` are the
637/// types from the `wgpu_core`, `webgpu`, and `custom` submodules of `wgpu::backend` that
638/// correspond to `D`. The macro generates `Deref` and `DerefMut` implementations that
639/// match on this enum and produce a `dyn I` reference for each variant.
640///
641/// The macro's `mut type` form defines `D` as the unique owner of the backend type, with
642/// a `DerefMut` implementation, and `as_*_mut` methods that return `&mut` references.
643/// This `D` does not implement `Clone`.
644///
645/// The macro's `ref type` form defines `D` to hold an `Arc` pointing to the backend type,
646/// permitting `Clone` and `Deref`, but losing exclusive, mutable access.
647///
648/// For example:
649///
650/// ```ignore
651/// dispatch_types! {ref type DispatchBuffer: BufferInterface =
652///                  CoreBuffer, WebBuffer, DynBuffer}
653/// ```
654///
655/// This defines `DispatchBuffer` as a type that dereferences to `&dyn BufferInterface`,
656/// which has methods like `map_async` and `destroy`. The enum would be:
657///
658/// ```ignore
659/// pub enum DispatchBuffer {
660///     #[cfg(wgpu_core)]
661///     Core(Arc<CoreBuffer>),
662///     #[cfg(webgpu)]
663///     WebGPU(WebBuffer),
664///     #[cfg(custom)]
665///     Custom(DynBuffer),
666/// }
667/// ```
668///
669/// This macro also defines `as_*` methods so that the backend implementations can
670/// dereference other arguments.
671///
672/// ## Devirtualization
673///
674/// The dispatch types generated by this macro are carefully designed to allow the
675/// compiler to completely devirtualize calls in most circumstances.
676///
677/// Note that every variant of the enum generated by this macro is under a `#[cfg]`.
678/// Naturally, the `match` expressions in the `Deref` and `DerefMut` implementations have
679/// matching `#[cfg]` attributes on each match arm.
680///
681/// In practice, when `wgpu`'s `"custom"` feature is not enabled, there is usually only
682/// one variant in the `enum`, making it effectively a newtype around the sole variant's
683/// data: it has no discriminant to branch on, and the `match` expressions are removed
684/// entirely by the compiler.
685///
686/// In this case, when we invoke a method from the interface trait `I` on a dispatch type,
687/// the `Deref` and `DerefMut` implementations' `match` statements build a `&dyn I` for
688/// the data, on which we immediately invoke a method. The vtable is a constant, allowing
689/// the Rust compiler to turn the `dyn` method call into an ordinary method call. This
690/// creates opportunities for inlining.
691///
692/// Similarly, the `as_*` methods are free when there is only one backend.
693macro_rules! dispatch_types {
694    (
695        ref type $name:ident: $interface:ident = $core_type:ident,$webgpu_type:ident,$custom_type:ident
696    ) => {
697        #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone)]
698        pub enum $name {
699            #[cfg(wgpu_core)]
700            Core(Arc<$core_type>),
701            #[cfg(webgpu)]
702            WebGPU($webgpu_type),
703            #[allow(clippy::allow_attributes, private_interfaces)]
704            #[cfg(custom)]
705            Custom($custom_type),
706        }
707
708        impl $name {
709            #[cfg(wgpu_core)]
710            #[inline]
711            #[allow(clippy::allow_attributes, unused)]
712            pub fn as_core(&self) -> &$core_type {
713                match self {
714                    Self::Core(value) => value,
715                    _ => panic!(concat!(stringify!($name), " is not core")),
716                }
717            }
718
719            #[cfg(wgpu_core)]
720            #[inline]
721            #[allow(clippy::allow_attributes, unused)]
722            pub fn as_core_opt(&self) -> Option<&$core_type> {
723                match self {
724                    Self::Core(value) => Some(value),
725                    _ => None,
726                }
727            }
728
729            #[cfg(custom)]
730            #[inline]
731            #[allow(clippy::allow_attributes, unused)]
732            pub fn as_custom<T: $interface>(&self) -> Option<&T> {
733                match self {
734                    Self::Custom(value) => value.downcast(),
735                    _ => None,
736                }
737            }
738
739            #[cfg(webgpu)]
740            #[inline]
741            #[allow(clippy::allow_attributes, unused)]
742            pub fn as_webgpu(&self) -> &$webgpu_type {
743                match self {
744                    Self::WebGPU(value) => value,
745                    _ => panic!(concat!(stringify!($name), " is not webgpu")),
746                }
747            }
748
749            #[cfg(webgpu)]
750            #[inline]
751            #[allow(clippy::allow_attributes, unused)]
752            pub fn as_webgpu_opt(&self) -> Option<&$webgpu_type> {
753                match self {
754                    Self::WebGPU(value) => Some(value),
755                    _ => None,
756                }
757            }
758
759            #[cfg(custom)]
760            #[inline]
761            pub fn custom<T: $interface>(t: T) -> Self {
762                Self::Custom($custom_type::new(t))
763            }
764        }
765
766        #[cfg(wgpu_core)]
767        impl From<$core_type> for $name {
768            #[inline]
769            fn from(value: $core_type) -> Self {
770                Self::Core(Arc::new(value))
771            }
772        }
773
774        #[cfg(webgpu)]
775        impl From<$webgpu_type> for $name {
776            #[inline]
777            fn from(value: $webgpu_type) -> Self {
778                Self::WebGPU(value)
779            }
780        }
781
782        impl core::ops::Deref for $name {
783            type Target = dyn $interface;
784
785            #[inline]
786            fn deref(&self) -> &Self::Target {
787                match self {
788                    #[cfg(wgpu_core)]
789                    Self::Core(value) => value.as_ref(),
790                    #[cfg(webgpu)]
791                    Self::WebGPU(value) => value,
792                    #[cfg(custom)]
793                    Self::Custom(value) => value.deref(),
794                    #[cfg(not(any(wgpu_core, webgpu)))]
795                    _ => panic!("No context available. You need to enable one of wgpu's backend feature build flags."),
796                }
797            }
798        }
799    };
800    (
801        mut type $name:ident: $interface:ident = $core_type:ident,$webgpu_type:ident,$custom_type:ident
802    ) => {
803        #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
804        pub enum $name {
805            #[cfg(wgpu_core)]
806            Core($core_type),
807            #[cfg(webgpu)]
808            WebGPU($webgpu_type),
809            #[allow(clippy::allow_attributes, private_interfaces)]
810            #[cfg(custom)]
811            Custom($custom_type),
812        }
813
814        impl $name {
815            #[cfg(wgpu_core)]
816            #[inline]
817            #[allow(clippy::allow_attributes, unused)]
818            pub fn as_core(&self) -> &$core_type {
819                match self {
820                    Self::Core(value) => value,
821                    _ => panic!(concat!(stringify!($name), " is not core")),
822                }
823            }
824
825            #[cfg(wgpu_core)]
826            #[inline]
827            #[allow(clippy::allow_attributes, unused)]
828            pub fn as_core_mut(&mut self) -> &mut $core_type {
829                match self {
830                    Self::Core(value) => value,
831                    _ => panic!(concat!(stringify!($name), " is not core")),
832                }
833            }
834
835            #[cfg(wgpu_core)]
836            #[inline]
837            #[allow(clippy::allow_attributes, unused)]
838            pub fn as_core_opt(&self) -> Option<&$core_type> {
839                match self {
840                    Self::Core(value) => Some(value),
841                    _ => None,
842                }
843            }
844
845            #[cfg(wgpu_core)]
846            #[inline]
847            #[allow(clippy::allow_attributes, unused)]
848            pub fn as_core_mut_opt(
849                &mut self,
850            ) -> Option<&mut $core_type> {
851                match self {
852                    Self::Core(value) => Some(value),
853                    _ => None,
854                }
855            }
856
857            #[cfg(custom)]
858            #[inline]
859            #[allow(clippy::allow_attributes, unused)]
860            pub fn as_custom<T: $interface>(&self) -> Option<&T> {
861                match self {
862                    Self::Custom(value) => value.downcast(),
863                    _ => None,
864                }
865            }
866
867            #[cfg(webgpu)]
868            #[inline]
869            #[allow(clippy::allow_attributes, unused)]
870            pub fn as_webgpu(&self) -> &$webgpu_type {
871                match self {
872                    Self::WebGPU(value) => value,
873                    _ => panic!(concat!(stringify!($name), " is not webgpu")),
874                }
875            }
876
877            #[cfg(webgpu)]
878            #[inline]
879            #[allow(clippy::allow_attributes, unused)]
880            pub fn as_webgpu_mut(&mut self) -> &mut $webgpu_type {
881                match self {
882                    Self::WebGPU(value) => value,
883                    _ => panic!(concat!(stringify!($name), " is not webgpu")),
884                }
885            }
886
887            #[cfg(webgpu)]
888            #[inline]
889            #[allow(clippy::allow_attributes, unused)]
890            pub fn as_webgpu_opt(&self) -> Option<&$webgpu_type> {
891                match self {
892                    Self::WebGPU(value) => Some(value),
893                    _ => None,
894                }
895            }
896
897            #[cfg(webgpu)]
898            #[inline]
899            #[allow(clippy::allow_attributes, unused)]
900            pub fn as_webgpu_mut_opt(
901                &mut self,
902            ) -> Option<&mut $webgpu_type> {
903                match self {
904                    Self::WebGPU(value) => Some(value),
905                    _ => None,
906                }
907            }
908
909            #[cfg(custom)]
910            #[inline]
911            pub fn custom<T: $interface>(t: T) -> Self {
912                Self::Custom($custom_type::new(t))
913            }
914        }
915
916        #[cfg(wgpu_core)]
917        impl From<$core_type> for $name {
918            #[inline]
919            fn from(value: $core_type) -> Self {
920                Self::Core(value)
921            }
922        }
923
924        #[cfg(webgpu)]
925        impl From<$webgpu_type> for $name {
926            #[inline]
927            fn from(value: $webgpu_type) -> Self {
928                Self::WebGPU(value)
929            }
930        }
931
932        impl core::ops::Deref for $name {
933            type Target = dyn $interface;
934
935            #[inline]
936            fn deref(&self) -> &Self::Target {
937                match self {
938                    #[cfg(wgpu_core)]
939                    Self::Core(value) => value,
940                    #[cfg(webgpu)]
941                    Self::WebGPU(value) => value,
942                    #[cfg(custom)]
943                    Self::Custom(value) => value.deref(),
944                    #[cfg(not(any(wgpu_core, webgpu)))]
945                    _ => panic!("No context available. You need to enable one of wgpu's backend feature build flags."),
946                }
947            }
948        }
949
950        impl core::ops::DerefMut for $name {
951            #[inline]
952            fn deref_mut(&mut self) -> &mut Self::Target {
953                match self {
954                    #[cfg(wgpu_core)]
955                    Self::Core(value) => value,
956                    #[cfg(webgpu)]
957                    Self::WebGPU(value) => value,
958                    #[cfg(custom)]
959                    Self::Custom(value) => value.deref_mut(),
960                    #[cfg(not(any(wgpu_core, webgpu)))]
961                    _ => panic!("No context available. You need to enable one of wgpu's backend feature build flags."),
962                }
963            }
964        }
965    };
966}
967
968dispatch_types! {ref type DispatchInstance: InstanceInterface = ContextWgpuCore, ContextWebGpu, DynContext}
969dispatch_types! {ref type DispatchAdapter: AdapterInterface = CoreAdapter, WebAdapter, DynAdapter}
970dispatch_types! {ref type DispatchDevice: DeviceInterface = CoreDevice, WebDevice, DynDevice}
971dispatch_types! {ref type DispatchQueue: QueueInterface = CoreQueue, WebQueue, DynQueue}
972dispatch_types! {ref type DispatchShaderModule: ShaderModuleInterface = CoreShaderModule, WebShaderModule, DynShaderModule}
973dispatch_types! {ref type DispatchBindGroupLayout: BindGroupLayoutInterface = CoreBindGroupLayout, WebBindGroupLayout, DynBindGroupLayout}
974dispatch_types! {ref type DispatchBindGroup: BindGroupInterface = CoreBindGroup, WebBindGroup, DynBindGroup}
975dispatch_types! {ref type DispatchTextureView: TextureViewInterface = CoreTextureView, WebTextureView, DynTextureView}
976dispatch_types! {ref type DispatchSampler: SamplerInterface = CoreSampler, WebSampler, DynSampler}
977dispatch_types! {ref type DispatchBuffer: BufferInterface = CoreBuffer, WebBuffer, DynBuffer}
978dispatch_types! {ref type DispatchTexture: TextureInterface = CoreTexture, WebTexture, DynTexture}
979dispatch_types! {ref type DispatchExternalTexture: ExternalTextureInterface = CoreExternalTexture, WebExternalTexture, DynExternalTexture}
980dispatch_types! {ref type DispatchBlas: BlasInterface = CoreBlas, WebBlas, DynBlas}
981dispatch_types! {ref type DispatchTlas: TlasInterface = CoreTlas, WebTlas, DynTlas}
982dispatch_types! {ref type DispatchQuerySet: QuerySetInterface = CoreQuerySet, WebQuerySet, DynQuerySet}
983dispatch_types! {ref type DispatchPipelineLayout: PipelineLayoutInterface = CorePipelineLayout, WebPipelineLayout, DynPipelineLayout}
984dispatch_types! {ref type DispatchRenderPipeline: RenderPipelineInterface = CoreRenderPipeline, WebRenderPipeline, DynRenderPipeline}
985dispatch_types! {ref type DispatchComputePipeline: ComputePipelineInterface = CoreComputePipeline, WebComputePipeline, DynComputePipeline}
986dispatch_types! {ref type DispatchPipelineCache: PipelineCacheInterface = CorePipelineCache, WebPipelineCache, DynPipelineCache}
987dispatch_types! {mut type DispatchCommandEncoder: CommandEncoderInterface = CoreCommandEncoder, WebCommandEncoder, DynCommandEncoder}
988dispatch_types! {mut type DispatchComputePass: ComputePassInterface = CoreComputePass, WebComputePassEncoder, DynComputePass}
989dispatch_types! {mut type DispatchRenderPass: RenderPassInterface = CoreRenderPass, WebRenderPassEncoder, DynRenderPass}
990dispatch_types! {mut type DispatchCommandBuffer: CommandBufferInterface = CoreCommandBuffer, WebCommandBuffer, DynCommandBuffer}
991dispatch_types! {mut type DispatchRenderBundleEncoder: RenderBundleEncoderInterface = CoreRenderBundleEncoder, WebRenderBundleEncoder, DynRenderBundleEncoder}
992dispatch_types! {ref type DispatchRenderBundle: RenderBundleInterface = CoreRenderBundle, WebRenderBundle, DynRenderBundle}
993dispatch_types! {ref type DispatchSurface: SurfaceInterface = CoreSurface, WebSurface, DynSurface}
994dispatch_types! {ref type DispatchSurfaceOutputDetail: SurfaceOutputDetailInterface = CoreSurfaceOutputDetail, WebSurfaceOutputDetail, DynSurfaceOutputDetail}
995dispatch_types! {mut type DispatchQueueWriteBuffer: QueueWriteBufferInterface = CoreQueueWriteBuffer, WebQueueWriteBuffer, DynQueueWriteBuffer}
996dispatch_types! {mut type DispatchBufferMappedRange: BufferMappedRangeInterface = CoreBufferMappedRange, WebBufferMappedRange, DynBufferMappedRange}
wgpu/dispatch.rs

wgpu/
dispatch.rs
