OMG Thanks So Much, Its Actually Ticking The Use CCD (Continues Collision Detection) BRU! Otherwise My Bullet Shells Were Just Traveling Through The Map, What An Annoyance, Seriously, Wasted Almost An Entire Day To Figure Something So Simple Out, Why Doesn’t UE Just Have CCD Ticked Normally And ONLY Allow Us To Untick it When We Need To, BRU
I have the same bug in UE 5.0.3. Tried to use p.bUseUnifiedHeightfield=0 console command, but it doesn’t help
I tried to enable Use CCD on the mesh, it helps, but not fully. In this case 80% of attempts to drop objects are succesful - they collide as supposed , but in 20% of cases they still fall through landscape.
Must have said this 10 times the past month.
Increase the landscape collision thickness.
I increased thickness from 128 to 500 and it got worse not better 
What thickness are you using?
Depends on the size of the object and its speed.
That said, there should not be any adverse effects from setting the thickness to huge numbers.
landscape collision thickness doesn’t work
Physics object will penetrate it in my test even with infinite collision thickness
But same object doesn’t penetrate regular cube with 3.0 Z-axis scale
3.0 Unreal Units on a standard cube is 3 units which happen to also be 3 meters.
If setting your landscape thickness to 6 doesnt stop the object falling, something is wron with your landacape (delete, start over), or your engine…
I thought the unreal engine unit was CM ? did it change ?
Also having issues with this, and also actual TSR crashes from it when items penetrate in the landscape half-way. On UE 5.4…
Anyone managed to fix this ?
Engine units have always been Uu.
Which map down to cm i think.
I can’t seem to find a landscape thickness option in UE 5.4, is it still a thing ?
@Mind-Brain
May be able to confirm. I haven’t touched UE5 in ages because it’s unreasonably broken.
I know, its painful, it does not seem to be there, I think we switched to unifiedheightfields… so no obvious solution 
Hey @Ahuaeyn1
As far as I know, Landscape Thickness was deprecated in 4.14 and so was probably removed since. I don’t work with landscapes often, I prefer more refined built areas in my projects, not big on landscapes.
What I know of are two options:
Use CCD and shorten your substep delta to increase the amount of physics ticks, the lowest I found that worked was somewhere around .002 but I advise against such a low tickrate. This will impact your performance significantly, and get exponentially heavier per physics object with this tickrate- but you could get better reactions with say .025 or .02 (default is .0333 I think?) I’m thinking with something heavy that the player interacts with- maybe like a big boulder to push- it only activates being a physics object when the player gets near enough, and then once its velocity reaches 0 AND the player is far away it stops being a physics object. After that, just keep the amount in range of the player to a minimum.
The other option is whatever it is you’re trying to do, maybe let it be computed by the system and let you THINK it’s physics. Say shooting a basketball- You can use arc prediction and have it follow that path, then on collision with the backboard use its momentum for a new arc downward, etc. In my experience, physics assets are highly reliable for one thing over anything else: Clipping 
Even in that exercise I was thinking of the basketball net cloth simulation clipping through the ball as it goes through the hoop.
Hope this helps! To start I’d try raising the substepping so it does more detections more often, but not TOO low.
Also, I’m going to mark this topic closed. It doesn’t need to be necro’d every few years, since the original issue has been long since resolved and completely changed over the years. It’s time for a new thread with modern issues and solutions, I think. 
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