hi, i’d like to aks what your preferred way is to make collisions for organic levelparts.
isn’t it possible to use the actual ground geometry somehow? do i still need to create convex forms?
thx in andvance!
sascha
Hi Sascha,
There a couple of ways to go about doing this for organic shapes.
The first method you can do in UE4 without having to add any collision meshes. You can open the mesh in the mesh viewer/editor and change the collision complexity from Default to “Use Complex Collision as Simple.”
This will use your current geometry as the collision mesh. I wouldn’t necessarily recommend this though because if the mesh has any sharp angular edges the collision won’t work as well. This can also be a performance hindrance because you now have two copies of your mesh that are being rendered. If it’s vertex heavy this can be a performance hit as well.
The second method would be to use your 3D modeling software (looks like you’re using Max) and make a lower resolution mesh for your collision. In Max there are a couple of modifiers that can make this easier and do a fairly good job with maintaining borders for your mesh and getting rid of anything else inbetween that isn’t needed.
Multi-Res and Proptimizer are the modifers to try. If you’ve not used these before just add them to your stack for your mesh and click generate in the details panel for them. Adjust the value from 100 to say 50 or 25. This will reduce the poly count to 50 % or 25 % of the original mesh polys.
I hope this helps and if you have any questions feel free to ask! 
Tim
ah, thank you tim! a colleague also hinted me to this “Use Complex Collision as Simple.” rollout just minutes ago.
this did the trick. i feared to somehow have to recreate the organic floors with convex closed meshes. that gave me shivers 
the optimizing tools are already known, but thank you anyway for your detailed answer!
solved!