Issue turned out to be that in some circumstances, the `group_by` iterator will create multiple groups for a single key - and sometimes those groups can be empty. This lead to situations where an animation track will end up empty until enough changed to re-shuffle things in the query iterator.
The fix is switching to `into_group_map_by` - which will put all grouped items into a hashmap instead, ensuring no duplicate keys.
…to avoid re-processing timeline info
- move generating animation to first thing in a frame, and notifying
about timeline changes to last, to ensure that it happens before the
time updates
- re-generate the animation tweens whenever you start playing or
manually seek a new time in the timeline to prevent inconsistencies
This PR adds an initial animation timeline.
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Co-authored-by: Brandon Thomas <echelon@gmail.com>
Co-authored-by: Danny McGee <dannymcgee@gmail.com>
Lee-Orr