[css-animationworklet] When do time-based animations run?

[majido]

From @RByers on September 22, 2016 15:50

Only when on-screen? What if some JS queries the value of one of it's output properties?

Can we look to WebAnim here? Eg. @shans says that WebAnim defines that the timestamp for an animation that hasn't started yet is null.

Copied from original issue: WICG/animation-worklet#6

[majido]

I believe this is now addressed in the specification here. Specifically:

• WorkletAnimation start logic follows the same logic as regular animations with some additional restrictions to allow setup for off-thread animators.
• WorkletAnimation is allowed to return stale computed style to Javascript thus not requiring a blocking sync from potentially off-thread animator running in worklet context.

Please re-open this issue if this does not address the initial concern.