On 29/08/2024 20:45, Michael Strauß wrote:
Yes, that makes sense. In any case, we shouldn't be using a system
timer, but simply record the timestamp at v-sync, and then pass this
precise timestamp to all AnimationTimers. It shouldn't matter when
Yeah, I still think however that this is not en
, 2024 at 11:45
*To: *
*Cc: *openjfx-dev@openjdk.org
*Subject: *Re: Bug: Times passed to AnimationTimer should not fluctuate
Yes, that makes sense. In any case, we shouldn't be using a system
timer, but simply record the timestamp at v-sync, and then pass this
precise timestamp to all AnimationTimers.
iscrepancy
(AbstractPrimaryTimer:264).
Does not explain the issue John raised though.
-andy
From: openjfx-dev on behalf of Michael Strauß
Date: Thursday, August 29, 2024 at 11:45
To:
Cc: openjfx-dev@openjdk.org
Subject: Re: Bug: Times passed to AnimationTimer should not fluctuate
Yes, that m
Yes, that makes sense. In any case, we shouldn't be using a system
timer, but simply record the timestamp at v-sync, and then pass this
precise timestamp to all AnimationTimers. It shouldn't matter when
AnimationTimers are invoked between frames, as long as the timestamp
corresponds to the v-sync s
I think they're a bit separate. Even with VSync, the time it takes to
kick the FX thread in action is still going to be between 0-30ms. If it
then passes `System.nanoTime()` to the AnimationRunnables, you're
basically saying that they should render a frame at the precise time of
VSync-Time +
The entire idea of using a system timer in the presence of v-sync is
wrong, it simply can't work reliably. We get accurate frame
synchronization for free from Direct3D, we should use that instead of
system timers.
There's a JBS issue with a detailed analysis:
https://bugs.openjdk.org/browse/JDK-81
TLDR; AnimationTimer is being fed a time not based on the time the next
frame is expected to be rendered but the time of when the FX thread is
finally scheduled to do the callbacks. This time fluctuates wildly, and
is a time that's useless for doing frame accurate calculations of
animations (s
