donner::editor::NothingToPresentRetry Class Reference

Paces re-posting a render request whose worker result had nothing to present. More...

#include "donner/editor/RenderCoordinator.h"

Public Types
using	Clock = std::chrono::steady_clock
	Steady clock used to pace identical retry attempts.

Public Member Functions
bool	noteFailure (const RenderAttemptIdentity &attempt, Clock::time_point now)
	Record that the result of attempt had nothing to present.
bool	mayPost (const RenderAttemptIdentity &attempt, Clock::time_point now) const
	Whether attempt may be posted at now.
bool	retryScheduled () const
	True while a retry of the failed request is still scheduled.
std::optional< float >	secondsUntilRetry (Clock::time_point now) const
	Seconds until the scheduled retry is due, or nullopt when none is scheduled or it is already due: the wake for it has fired, and the next frame that asks for a render posts it.
void	reset ()
	Forget the failed request, once a result presents or the document is replaced.

Static Public Attributes
static constexpr std::array< std::chrono::milliseconds, 3 >	kRetryDelays
	Delay before each successive retry of the same failed request.

Detailed Description

Paces re-posting a render request whose worker result had nothing to present.

Such a result (no compositor tile: a failed readback, a lost device, refused surfaces) marks nothing rendered, and every idle frame asks for a render, so without pacing the identical request would be posted again on every frame. The failed request may be posted again after each delay in kRetryDelays; once the last retry fails too, an identical request is held until something about it changes. A different request is never held.

Member Function Documentation

mayPost()

bool donner::editor::NothingToPresentRetry::mayPost ( const RenderAttemptIdentity & attempt, Clock::time_point now ) const

nodiscard

Whether attempt may be posted at now.

Parameters

attempt	The request about to be posted.
now	Current time.

noteFailure()

bool donner::editor::NothingToPresentRetry::noteFailure	(	const RenderAttemptIdentity &	attempt,
		Clock::time_point	now )

Record that the result of attempt had nothing to present.

Parameters

attempt	The request that produced the result.
now	Current time.

Returns

True when this failure used up the last retry.

secondsUntilRetry()

std::optional< float > donner::editor::NothingToPresentRetry::secondsUntilRetry ( Clock::time_point now ) const

nodiscard

Seconds until the scheduled retry is due, or nullopt when none is scheduled or it is already due: the wake for it has fired, and the next frame that asks for a render posts it.

Parameters

now	Current time.

Member Data Documentation

kRetryDelays

std::array<std::chrono::milliseconds, 3> donner::editor::NothingToPresentRetry::kRetryDelays

staticconstexpr

Initial value:

= {
      std::chrono::milliseconds(100), std::chrono::milliseconds(500),
      std::chrono::milliseconds(2000)}

Delay before each successive retry of the same failed request.

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The documentation for this class was generated from the following file:

• donner/editor/RenderCoordinator.h