Wayland presentation extension (video protocol) WIP after RFCv2

Michel Dänzer michel at daenzer.net
Fri Apr 13 10:29:07 UTC 2018

On 2018-04-13 11:43 AM, Daniel Stone wrote:
> On 13 April 2018 at 10:17, Michel Dänzer <michel at daenzer.net> wrote:
>> Also, both higher-level APIs I know of which allow the application to
>> specify a target timestamp for presentation (VDPAU and
>> VK_GOOGLE_display_timing) use "not before" semantics. So, maybe the
>> not_before flag can be dropped, and flags can be added later for
>> different semantics, if a need for them ever materializes.

Just to be clear, I meant that the default semantics should be "not before".

> ... that being said, VK_GOOGLE_display_timing's 'present margin' is
> probably enough to cover these, rather than having to deal in absolute
> timestamps.

Not sure what you mean. presentMargin is the amount of time the
application could have delayed the vkQueuePresentKHR call while still
allowing to meet the desiredPresentTime as closely as possible. It
doesn't affect that the image shouldn't be presented before

Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer

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