How to add actor's location in TArray in Tick using c++?

Yes, you can do that but given the number of elements you will be adding I’d suggest one or more of the following:

  • Be sure to initialise your array to a suitable (large) number of elements to avoid needing to allocate / reallocate lots of memory as the array increases in size
  • Use some sort of smoothing. When I’ve made systems like this before I’ve tried where possible to make it more of a keyframe system with interpolation between those points. Keyframes would normally be made at important points. The exact implementation / suitability depend on your game of course
  • Consider using Network Replay Capture features of UE4 (Unreal Engine 4.6 Released! - Unreal Engine). May be suitable, may not be depending on your game

Reading some of this might help: TArray: Arrays in Unreal Engine | Unreal Engine Documentation The Slack feature may prove interesting whilst you’re developing / optimising.