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Add force in event tick eventually crashes

Surely there is a simple explanation. I have an actor that I apply force to continously in an Event Tick. The more I add the faster the game will crash and I can also see that the collision isn’t able to keep up anymore, starting to lag behind the actor.

Is adding force in an Event Tick bad? I thought Add Force already accounts for delta seconds at least.

Yes that certainly shouldn’t crash. Do you get a call stack or other information when it crashes?

I don’t get anything. After some more testing I’m not sure it’s actually crashing, it’s just that the game “freezes”. Is this considered a crash? I noticed the same thing happens at some point when I fall down from the map into empty space. But it’s not like the editor is crashing or anything.

Are there limitations in the physics engine? I really don’t have any experience with this type of thing. For example, if I apply a force equal to what a 60000 gravity would cause (much more than I need but just for arguments sake), the collision doesn’t work anymore and the actor just moves through the ceiling. Seems that happens because the trace lags behind quite a bit. Both Add Force and the collsion are running per tick in the blueprint though. Can’t quite wrap my head around why the trace starts to lag behind if both is updated every tick.

Hi Gigantoad,

I haven’t reproduced this yet, and we would like to look into this further. So we can take the proper approach for a potential bug, can you please make a Bug Report for this over on the AnswerHub: https://answers.unrealengine.com/index.html

Please include a screenshot of your Blueprint to show how you are applying the force to the actor, as well as mentioning any specific steps or settings which will help us to reproduce this.

Thanks!