# How to predict projectile bounce? **URL:** \ **Category:** World Creation\ **Tags:** bounce, unreal-engine, projectile, question\ **Created:** [May 15, 2015, 5:54pm UTC](https://forums.unrealengine.com/t/how-to-predict-projectile-bounce/318753 "2015-05-15T17:54:54Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![intoxicat3](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@intoxicat3](https://forums.unrealengine.com/u/intoxicat3)\ **Post date:** [May 15, 2015, 5:54pm UTC](https://forums.unrealengine.com/t/how-to-predict-projectile-bounce/318753/1 "2015-05-15T17:54:54Z")
Is there any way to predict projectile bounce? My calculations are different than Projectile Movement Bounce. I’m using actor with projectile movement (bounce set to true) but it’s bouncing different than my simple calculations for bounce. ---
**Author:** ![anonymous\_user\_199281e7](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_199281e7](https://forums.unrealengine.com/u/anonymous_user_199281e7)\ **Post date:** [May 15, 2015, 6:50pm UTC](https://forums.unrealengine.com/t/how-to-predict-projectile-bounce/318753/2 "2015-05-15T18:50:03Z")
not really sure how your predicting your bounces… however if there not lining up with your auctial bounces its most likely an issue with the size and shape of the projectile and the prediction … i.e if its a ball that bouncing off of a wall that ball is likely not a perfect ball and the engine is just getting the few vertices that are colliding and if your using a thin line for your predictions its not likely hitting straight on the wall. with a higher res ball this would likely be a small but notifiable deviation, with a low res ball this could really be a large deviation. only advise i can offer is to try using the same object for prediction and auctial \* your prediction ball could even be invisible and just log a path for another graphic is the only way i could advise… this would also take any weight on the projectile in to account etc. witch could also be the prob. sry if its kinda a vague answer not totally sure what you are working with here. ---
**Author:** ![InterSlayer](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@InterSlayer](https://forums.unrealengine.com/u/InterSlayer)\ **Post date:** [May 19, 2015, 9:41pm UTC](https://forums.unrealengine.com/t/how-to-predict-projectile-bounce/318753/3 "2015-05-19T21:41:49Z")
> **[A new, community-hosted Unreal Engine Wiki](https://forums.unrealengine.com/t/a-new-community-hosted-unreal-engine-wiki/141494)** > > After over a year in maintenance mode, the official Unreal Engine Wiki is now permanently offline. These resources now live on a new community-run Unreal Engine Community Wiki — ue4community.wiki! You will be able to find content from the official... I was able to calculate projectile paths using above + DrawDebugLine. My specific circumstance was 2D in 3D space, and assume it would work just as well for full 3D bouncing. ---
**Author:** ![Vahid](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Vahid](https://forums.unrealengine.com/u/Vahid)\ **Post date:** [September 29, 2016, 2:01pm UTC](https://forums.unrealengine.com/t/how-to-predict-projectile-bounce/318753/4 "2016-09-29T14:01:38Z")
I need this too