GeodeCallbackState.h File Reference

Lifetime helpers for asynchronous WebGPU callback userdata. More...

#include <memory>
#include <utility>
#include <webgpu/webgpu.hpp>

Include dependency graph for GeodeCallbackState.h:

Namespaces
namespace	donner
	Top-level Donner namespace, which is split into different sub-namespaces such as donner::svg and donner::css.

Functions
template<typename State>
void *	donner::geode::retainWgpuCallbackState (const std::shared_ptr< State > &state)
	Retains callback state independently of the initiating stack frame.
template<typename State>
std::shared_ptr< State >	donner::geode::takeWgpuCallbackState (void *userdata)
	Transfers ownership retained by retainWgpuCallbackState into the callback.
template<typename State>
void	donner::geode::notifyWhenSubmittedWorkDone (const wgpu::Queue &queue, const std::shared_ptr< State > &state)
	Registers a submitted-work-done callback for all work currently submitted to queue, in the AllowSpontaneous callback mode. State must expose onWorkDone(), which runs exactly once when the queue drains, typically during a device.poll(...) (it may also run on submit or during another thread's poll), on whichever thread drives the queue at that point.

Detailed Description

Lifetime helpers for asynchronous WebGPU callback userdata.

Function Documentation

notifyWhenSubmittedWorkDone()

template<typename State>

void donner::geode::notifyWhenSubmittedWorkDone	(	const wgpu::Queue &	queue,
		const std::shared_ptr< State > &	state )

Registers a submitted-work-done callback for all work currently submitted to queue, in the AllowSpontaneous callback mode. State must expose onWorkDone(), which runs exactly once when the queue drains, typically during a device.poll(...) (it may also run on submit or during another thread's poll), on whichever thread drives the queue at that point.

Parameters

queue	Queue whose currently-submitted work is observed.
state	Shared callback state; retained until the callback runs.

retainWgpuCallbackState()

template<typename State>

void * donner::geode::retainWgpuCallbackState

(

const std::shared_ptr< State > &

state

)

Retains callback state independently of the initiating stack frame.

WebGPU callbacks may run after a bounded wait returns, and on another thread. The callback owns the returned userdata until it calls takeWgpuCallbackState, so releasing the initiating frame cannot leave WebGPU with a dangling pointer.

Parameters

state

Shared callback state to retain.

Returns

Opaque userdata owned by the eventual callback.

takeWgpuCallbackState()

template<typename State>

std::shared_ptr< State > donner::geode::takeWgpuCallbackState

(

void *

userdata

)

Transfers ownership retained by retainWgpuCallbackState into the callback.

Parameters

userdata

Opaque userdata returned by retainWgpuCallbackState.

Returns

Shared callback state owned by the callback invocation.