AF Manager class for dynamic animation frame request/cancel

[phoenixbf]

See #1342

[gkjohnson]

Great, thanks! A couple comments but I think this is the right direction

[gkjohnson]

Lets call this FrameScheduler for now.

[gkjohnson]

When changing the system being used for callbacks we will have to cancel all previous callbacks and reregister them with the new function. Eg if the "LRUCache" schedules an unload event it will be waiting until that event fires before scheduling another one. So if the last event is scheduled using the "xrSession" callback and then the session closes, the scheduled callback will never be fired.

So we'll need to keep track of all scheduled callbacks and rAF handles to swap over the scheduled events.

[gkjohnson]

@phoenixbf - just wanted to check in to see if you had any more questions on the changes needed here.

[phoenixbf]

@phoenixbf - just wanted to check in to see if you had any more questions on the changes needed here.

Hi, performing some local testing in order to have a clean rAF tracking system and handling swaps

[phoenixbf]

I've added management of pending AF.
It basically keeps track of requested AFs via handle as suggested, providing methods to cancel or flush all pending AFs. When entering XR session, it internally flushes and completes all pending, switching to this.xrsession.requestAnimationFrame for new requests.

So far I tried the above logic in both local and online setups without any evident issues, also with mutiple tsets. If this is the right direction, it should be probably instantiated in TilesRendererBase and then referenced by LRUCache, PriorityQueue, etc. during their initializations

[gkjohnson]

Thanks the direction of this looks great. I think we can cut down on some code redundancy in the implementation but we can deal with that once everything is working.

If this is the right direction, it should be probably instantiated in TilesRendererBase and then referenced by LRUCache, PriorityQueue, etc. during their initializations

This sounds good to me. Looks like the "LRUCache", "PriorityQueue", the "throttle" function, and "QueryManager" are all places where rAF is used (though the throttle function can maybe be changed to "queueMicrotask")