pub trait Queue: WasmNotSendSync {
type A: Api;
// Required methods
unsafe fn submit(
&self,
command_buffers: &[&<Self::A as Api>::CommandBuffer],
surface_textures: &[&<Self::A as Api>::SurfaceTexture],
signal_fence: (&mut <Self::A as Api>::Fence, FenceValue)
) -> Result<(), DeviceError>;
unsafe fn present(
&self,
surface: &<Self::A as Api>::Surface,
texture: <Self::A as Api>::SurfaceTexture
) -> Result<(), SurfaceError>;
unsafe fn get_timestamp_period(&self) -> f32;
}
Required Associated Types§
Required Methods§
sourceunsafe fn submit(
&self,
command_buffers: &[&<Self::A as Api>::CommandBuffer],
surface_textures: &[&<Self::A as Api>::SurfaceTexture],
signal_fence: (&mut <Self::A as Api>::Fence, FenceValue)
) -> Result<(), DeviceError>
unsafe fn submit( &self, command_buffers: &[&<Self::A as Api>::CommandBuffer], surface_textures: &[&<Self::A as Api>::SurfaceTexture], signal_fence: (&mut <Self::A as Api>::Fence, FenceValue) ) -> Result<(), DeviceError>
Submit command_buffers
for execution on GPU.
Update fence
to value
when the operation is complete. See
Fence
for details.
A wgpu_hal
queue is “single threaded”: all command buffers are
executed in the order they’re submitted, with each buffer able to see
previous buffers’ results. Specifically:
-
If two calls to
submit
on a singleQueue
occur in a particular order (that is, they happen on the same thread, or on two threads that have synchronized to establish an ordering), then the first submission’s commands all complete execution before any of the second submission’s commands begin. All results produced by one submission are visible to the next. -
Within a submission, command buffers execute in the order in which they appear in
command_buffers
. All results produced by one buffer are visible to the next.
If two calls to submit
on a single Queue
from different threads are
not synchronized to occur in a particular order, they must pass distinct
Fence
s. As explained in the Fence
documentation, waiting for
operations to complete is only trustworthy when operations finish in
order of increasing fence value, but submissions from different threads
cannot determine how to order the fence values if the submissions
themselves are unordered. If each thread uses a separate Fence
, this
problem does not arise.
Valid usage:
-
All of the
CommandBuffer
s were created fromCommandEncoder
s that are associated with this queue. -
All of those
CommandBuffer
s must remain alive until the submitted commands have finished execution. (Since command buffers must not outlive their encoders, this implies that the encoders must remain alive as well.) -
All resources used by a submitted
CommandBuffer
(Texture
s,BindGroup
s,RenderPipeline
s, and so on) must remain alive until the command buffer finishes execution. -
Every
SurfaceTexture
that any command incommand_buffers
writes to must appear in thesurface_textures
argument. -
No
SurfaceTexture
may appear in thesurface_textures
argument more than once. -
Each
SurfaceTexture
insurface_textures
must be configured for use with theDevice
associated with thisQueue
, typically by callingSurface::configure
. -
All calls to this function that include a given
SurfaceTexture
insurface_textures
must use the sameFence
.