[Mesa-dev] [PATCH 3/3] glx/dri3: Request non-vsynced Present for swapinterval zero.

[Eero Tamminen]

Hi,

On 12/15/2014 07:46 AM, Keith Packard wrote:
> Mario Kleiner <mario.kleiner.de at gmail.com> writes:
>
>> Restores proper immediate tearing swap behaviour for
>> OpenGL bufferswap under DRI3/Present.
>
> Hrm. I'd love for this to be controlled by the GLX_EXT_swap_control_tear
> extension, but that one uses negative interval values to indicate
> tearing, instead of providing a new API, and we can't tell the
> difference between 0 and -0.
>
> Are you sure you don't want GLX_EXT_swap_control_tear and an interval of
> -1 instead of an interval of 0 with tearing?

Interval 0 is used for benchmarking.

It's expected to do whatever is fastest, that's what your
competitors already do.

(Quick check on Windows 8.1 Intel driver indicates that
in windowed/composited mode frames can even get dropped
although in fullscreen mode every tearing frame is shown.)


	- Eero