Collision on steep angled terrain

We have built a mountainous terrain in our game with several angles too steep to climb (often you slide down the side) but we’ve run into a snag with the collision. We consistently fall through the terrain when falling. Even just creating terrain with the UE4 toolkits and the 3rd person blueprint template you can walk up to the steeper hills and jump against them until you eventually clip through it and fall.

I’ve created several levels with multiple projects and UE4 versions(4.0.2, 4.1.0, 4.1.1) and this is consistent across them all. I tried adjusting the character capsule larger and smaller and playing with the terrain collision thickness property but nothing seems to help. Any suggestions?

I am also experiencing the same issue.

I am also having this issue. I have files if needed @ Epic

Have you tried enabling “Continuous Collision Detection” or CCD on your character?

#This Has Been Going on Since the Beta

I’ve been in dialogue with Epic about this since the Beta.

Collision on Landscapes used to be Heavenly Perfect

Then Physx 3.3 came around, and it’s never been fully fixed.

I NEED Landscapes to work for my game!

It used to be extremely frequent that my character would fall through landscape, post Physx 3.3. (pre UE4 release)

Now it is still frequent enough that I classify Landscapes as broken

#It’s Not Epic’s Fault

As far as I know the reason this is going on is because of bugs in the Physx 3.3 code, and Epic has been in dialogue with them about it for some time now.

#Landscapes are still Broken

Epic please have Nvidia fix this as soon as you can!

Thank youuuu!

PS: I’ve been resisting making my own post so I am now venting here.

PSS: I can’t release a game in UE4 as I want to, with Landscapes, until this fixed.

#Prior Threads on This Topic for Reference

I absolutely encourage the existence of this current thread, these other links are for Epic’s and Porter’s Reference




for the info , it is very much appreciated

I too have this issue. On some places I keep falling through the terrain. It mostly happens when coming up to a steep wall etc… I am going to solve this by adding extra collision walls but somehow I wonder if there is a bug in the terrain part?

Best regards/


This issue has been fixed and will be in 4.3 !

#Solution Thread


Still having the same bug… 4.4.3

It’s back in 4.7.1.

Hi GuyPaddock,

I have not been able to reproduce this on my end. Can you be a bit more specific. Are you retopologizing your terrain or is it after simply using a strong strength sculpt tool? How steep is the angle of the landscape before you see the collision error?

Hi everyone,

While I was unable to reproduce this error on my end, we have had a number of users experience this collision bug. I went ahead and put in a bug report, UE-11447 to be assessed by the development staff. Can you try the workaround suggested below and see if that fixes your error:

Hi Guy,

We just fixed a new bug in 4.7 where collision for landscape components containing XY offset data (generated by the Retopologize tool) was broken. The fix will be in 4.7.3 which should be out next week. If you’re using source code you can apply the fix directly before then if you’d like:


Thought I’d mention that I just encountered this bug in 4.10.1.
No retopology, simply sculpting and smoothing. changing the component size and then back again seemed to fix it temporarily but with more sculpting it happened again.

Hi ,

The fixes for this came through in 4.7. Can you list what steps you are taking to reproduce this in a clean, blank project with no additional content? Is your landscape created in editor or imported from an outside source such as World Machine?