Reversing timeline

We don't have plans to support it at the moment, as not all playables types used by timeline can support it.

 

Could you explain the use case? It's always helpful when we understand the problem you are trying to solve, as opposed to the feature you need to solve it.

 

You can play it in reverse by setting playableDirector.time via script and then

• Manually evaluating it from script using playableDirector.Evaluate()
• OR setting playableDirector.playableGraph.GetRootPlayable(0).SetSpeed(0); after calling the playableDirector is playing (plays at a speed of 0).

The latter option will keep the engine playing timeline, which occurs between Update() and LateUpdate(). This is more efficient because timeline animation will be evaluated during the normal animation evaluation phase. When using Evaluate(), the animation phase needs be to run again.

What won't work however is

• Audio
• Signals/Notfications
• Cinemachine cameras with noise or effects that rely on the previous frame may give different results than playing forward.
• Any custom playables that expect time to go forward.
• Particles will work, but will be less efficient, as moving backwards causes them to re-simulate from the start of the clip.

So if these are acceptable trade-offs, then it can be scripted.

I hope that helps. And thanks for the updated use-case.

 

The efficiency should be roughly equivalent. Animation might be slightly slower, as animation clips are optimized for forward playback, but it may not be a noticeable difference.

For particles, I'd recommend measuring. I did some measurements recently and was pleasantly surprised how efficient the simulation was. It will be slower, but the length and complexity of particles will determine how much slower.