delta time is a float value, the time spent since the previous tick. This is tied to FPS. every frame is called a “tick”, so 60 FPS is 60 ticks a second.
If you move object X 10 units per tick, someone playing a game with 60 FPS vs someone playing with 400 FPS will see the object move at different speeds. To ensure that both players regardless of FPS will see object X move at the same speed, the speed is multiplied with world delta seconds.
the “Tick” method provides world delta seconds as function argument. If not using the Tick method, you can access the World Delta Seconds from Gameplay Statics
Get World Delta Seconds | Unreal Engine 5.5 Documentation | Epic Developer Community
Multiply the speed of any effect that requires it.
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