Struct ComputePass 

pub struct ComputePass<'encoder> { /* private fields */ }

In-progress recording of a compute pass.

It can be created with CommandEncoder::begin_compute_pass.

Corresponds to WebGPU GPUComputePassEncoder.

Implementations

impl ComputePass<'_>

pub fn forget_lifetime(self) -> ComputePass<'static>

Drops the lifetime relationship to the parent command encoder, making usage of the encoder while this pass is recorded a run-time error instead.

Attention: As long as the compute pass has not been ended, any mutating operation on the parent command encoder will cause a run-time error and invalidate it! By default, the lifetime constraint prevents this, but it can be useful to handle this at run time, such as when storing the pass and encoder in the same data structure.

This operation has no effect on pass recording. It’s a safe operation, since CommandEncoder is in a locked state as long as the pass is active regardless of the lifetime constraint or its absence.

pub fn set_bind_group<'a, BG>( &mut self, index: u32, bind_group: BG, offsets: &[u32], )

where Option<&'a BindGroup>: From<BG>,

Sets the active bind group for a given bind group index. The bind group layout in the active pipeline when the dispatch() function is called must match the layout of this bind group.

If the bind group have dynamic offsets, provide them in the binding order. These offsets have to be aligned to Limits::min_uniform_buffer_offset_alignment or Limits::min_storage_buffer_offset_alignment appropriately.

Examples found in repository

examples/shader/gpu_readback.rs (line 234)

    fn run(
        &self,
        _graph: &mut render_graph::RenderGraphContext,
        render_context: &mut RenderContext,
        world: &World,
    ) -> Result<(), render_graph::NodeRunError> {
        let pipeline_cache = world.resource::<PipelineCache>();
        let pipeline = world.resource::<ComputePipeline>();
        let bind_group = world.resource::<GpuBufferBindGroup>();

        if let Some(init_pipeline) = pipeline_cache.get_compute_pipeline(pipeline.pipeline) {
            let mut pass =
                render_context
                    .command_encoder()
                    .begin_compute_pass(&ComputePassDescriptor {
                        label: Some("GPU readback compute pass"),
                        ..default()
                    });

            pass.set_bind_group(0, &bind_group.0, &[]);
            pass.set_pipeline(init_pipeline);
            pass.dispatch_workgroups(BUFFER_LEN as u32, 1, 1);
        }
        Ok(())
    }

examples/shader/compute_shader_game_of_life.rs (line 291)

    fn run(
        &self,
        _graph: &mut render_graph::RenderGraphContext,
        render_context: &mut RenderContext,
        world: &World,
    ) -> Result<(), render_graph::NodeRunError> {
        let bind_groups = &world.resource::<GameOfLifeImageBindGroups>().0;
        let pipeline_cache = world.resource::<PipelineCache>();
        let pipeline = world.resource::<GameOfLifePipeline>();

        let mut pass = render_context
            .command_encoder()
            .begin_compute_pass(&ComputePassDescriptor::default());

        // select the pipeline based on the current state
        match self.state {
            GameOfLifeState::Loading => {}
            GameOfLifeState::Init => {
                let init_pipeline = pipeline_cache
                    .get_compute_pipeline(pipeline.init_pipeline)
                    .unwrap();
                pass.set_bind_group(0, &bind_groups[0], &[]);
                pass.set_pipeline(init_pipeline);
                pass.dispatch_workgroups(SIZE.x / WORKGROUP_SIZE, SIZE.y / WORKGROUP_SIZE, 1);
            }
            GameOfLifeState::Update(index) => {
                let update_pipeline = pipeline_cache
                    .get_compute_pipeline(pipeline.update_pipeline)
                    .unwrap();
                pass.set_bind_group(0, &bind_groups[index], &[]);
                pass.set_pipeline(update_pipeline);
                pass.dispatch_workgroups(SIZE.x / WORKGROUP_SIZE, SIZE.y / WORKGROUP_SIZE, 1);
            }
        }

        Ok(())
    }

pub fn set_pipeline(&mut self, pipeline: &ComputePipeline)

Sets the active compute pipeline.

Examples found in repository

examples/shader/gpu_readback.rs (line 235)

    fn run(
        &self,
        _graph: &mut render_graph::RenderGraphContext,
        render_context: &mut RenderContext,
        world: &World,
    ) -> Result<(), render_graph::NodeRunError> {
        let pipeline_cache = world.resource::<PipelineCache>();
        let pipeline = world.resource::<ComputePipeline>();
        let bind_group = world.resource::<GpuBufferBindGroup>();

        if let Some(init_pipeline) = pipeline_cache.get_compute_pipeline(pipeline.pipeline) {
            let mut pass =
                render_context
                    .command_encoder()
                    .begin_compute_pass(&ComputePassDescriptor {
                        label: Some("GPU readback compute pass"),
                        ..default()
                    });

            pass.set_bind_group(0, &bind_group.0, &[]);
            pass.set_pipeline(init_pipeline);
            pass.dispatch_workgroups(BUFFER_LEN as u32, 1, 1);
        }
        Ok(())
    }

examples/shader/compute_shader_game_of_life.rs (line 292)

    fn run(
        &self,
        _graph: &mut render_graph::RenderGraphContext,
        render_context: &mut RenderContext,
        world: &World,
    ) -> Result<(), render_graph::NodeRunError> {
        let bind_groups = &world.resource::<GameOfLifeImageBindGroups>().0;
        let pipeline_cache = world.resource::<PipelineCache>();
        let pipeline = world.resource::<GameOfLifePipeline>();

        let mut pass = render_context
            .command_encoder()
            .begin_compute_pass(&ComputePassDescriptor::default());

        // select the pipeline based on the current state
        match self.state {
            GameOfLifeState::Loading => {}
            GameOfLifeState::Init => {
                let init_pipeline = pipeline_cache
                    .get_compute_pipeline(pipeline.init_pipeline)
                    .unwrap();
                pass.set_bind_group(0, &bind_groups[0], &[]);
                pass.set_pipeline(init_pipeline);
                pass.dispatch_workgroups(SIZE.x / WORKGROUP_SIZE, SIZE.y / WORKGROUP_SIZE, 1);
            }
            GameOfLifeState::Update(index) => {
                let update_pipeline = pipeline_cache
                    .get_compute_pipeline(pipeline.update_pipeline)
                    .unwrap();
                pass.set_bind_group(0, &bind_groups[index], &[]);
                pass.set_pipeline(update_pipeline);
                pass.dispatch_workgroups(SIZE.x / WORKGROUP_SIZE, SIZE.y / WORKGROUP_SIZE, 1);
            }
        }

        Ok(())
    }

pub fn insert_debug_marker(&mut self, label: &str)

Inserts debug marker.

pub fn push_debug_group(&mut self, label: &str)

Start record commands and group it into debug marker group.

pub fn pop_debug_group(&mut self)

Stops command recording and creates debug group.

pub fn dispatch_workgroups(&mut self, x: u32, y: u32, z: u32)

Dispatches compute work operations.

x, y and z denote the number of work groups to dispatch in each dimension.

Examples found in repository

examples/shader/gpu_readback.rs (line 236)

    fn run(
        &self,
        _graph: &mut render_graph::RenderGraphContext,
        render_context: &mut RenderContext,
        world: &World,
    ) -> Result<(), render_graph::NodeRunError> {
        let pipeline_cache = world.resource::<PipelineCache>();
        let pipeline = world.resource::<ComputePipeline>();
        let bind_group = world.resource::<GpuBufferBindGroup>();

        if let Some(init_pipeline) = pipeline_cache.get_compute_pipeline(pipeline.pipeline) {
            let mut pass =
                render_context
                    .command_encoder()
                    .begin_compute_pass(&ComputePassDescriptor {
                        label: Some("GPU readback compute pass"),
                        ..default()
                    });

            pass.set_bind_group(0, &bind_group.0, &[]);
            pass.set_pipeline(init_pipeline);
            pass.dispatch_workgroups(BUFFER_LEN as u32, 1, 1);
        }
        Ok(())
    }

examples/shader/compute_shader_game_of_life.rs (line 293)

    fn run(
        &self,
        _graph: &mut render_graph::RenderGraphContext,
        render_context: &mut RenderContext,
        world: &World,
    ) -> Result<(), render_graph::NodeRunError> {
        let bind_groups = &world.resource::<GameOfLifeImageBindGroups>().0;
        let pipeline_cache = world.resource::<PipelineCache>();
        let pipeline = world.resource::<GameOfLifePipeline>();

        let mut pass = render_context
            .command_encoder()
            .begin_compute_pass(&ComputePassDescriptor::default());

        // select the pipeline based on the current state
        match self.state {
            GameOfLifeState::Loading => {}
            GameOfLifeState::Init => {
                let init_pipeline = pipeline_cache
                    .get_compute_pipeline(pipeline.init_pipeline)
                    .unwrap();
                pass.set_bind_group(0, &bind_groups[0], &[]);
                pass.set_pipeline(init_pipeline);
                pass.dispatch_workgroups(SIZE.x / WORKGROUP_SIZE, SIZE.y / WORKGROUP_SIZE, 1);
            }
            GameOfLifeState::Update(index) => {
                let update_pipeline = pipeline_cache
                    .get_compute_pipeline(pipeline.update_pipeline)
                    .unwrap();
                pass.set_bind_group(0, &bind_groups[index], &[]);
                pass.set_pipeline(update_pipeline);
                pass.dispatch_workgroups(SIZE.x / WORKGROUP_SIZE, SIZE.y / WORKGROUP_SIZE, 1);
            }
        }

        Ok(())
    }

pub fn dispatch_workgroups_indirect( &mut self, indirect_buffer: &Buffer, indirect_offset: u64, )

Dispatches compute work operations, based on the contents of the indirect_buffer.

The structure expected in indirect_buffer must conform to DispatchIndirectArgs.

impl ComputePass<'_>

Features::PUSH_CONSTANTS must be enabled on the device in order to call these functions.

pub fn set_push_constants(&mut self, offset: u32, data: &[u8])

Set push constant data for subsequent dispatch calls.

Write the bytes in data at offset offset within push constant storage. Both offset and the length of data must be multiples of PUSH_CONSTANT_ALIGNMENT, which is always 4.

For example, if offset is 4 and data is eight bytes long, this call will write data to bytes 4..12 of push constant storage.

impl ComputePass<'_>

Features::TIMESTAMP_QUERY_INSIDE_PASSES must be enabled on the device in order to call these functions.

pub fn write_timestamp(&mut self, query_set: &QuerySet, query_index: u32)

Issue a timestamp command at this point in the queue. The timestamp will be written to the specified query set, at the specified index.

Must be multiplied by Queue::get_timestamp_period to get the value in nanoseconds. Absolute values have no meaning, but timestamps can be subtracted to get the time it takes for a string of operations to complete.

impl ComputePass<'_>

Features::PIPELINE_STATISTICS_QUERY must be enabled on the device in order to call these functions.

pub fn begin_pipeline_statistics_query( &mut self, query_set: &QuerySet, query_index: u32, )

Start a pipeline statistics query on this compute pass. It can be ended with end_pipeline_statistics_query. Pipeline statistics queries may not be nested.

pub fn end_pipeline_statistics_query(&mut self)

End the pipeline statistics query on this compute pass. It can be started with begin_pipeline_statistics_query. Pipeline statistics queries may not be nested.

Trait Implementations

impl<'encoder> Debug for ComputePass<'encoder>

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Hash for ComputePass<'_>

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for ComputePass<'_>

fn cmp(&self, other: &ComputePass<'_>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for ComputePass<'_>

fn eq(&self, other: &ComputePass<'_>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for ComputePass<'_>

fn partial_cmp(&self, other: &ComputePass<'_>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for ComputePass<'_>