undo actor combining

Hello all,

to begin: I have a really hard time understanding optimization in UE4, I just can’t wrap my head around it.

I wanted to increase my fps and had read somewhere that combining actors to one bigger mesh should improve framerate etc.
but I combined some objects a little too much, this resulted in always having the same (combined) actor rendered constantly. which should be split in 3 or 4 seperate actors to improve framerate.
I can’t undo the combining anymore because it hit me quite late that I had to split it.

is there a way to decombine/seperate/detach the models from each other?

with kind regards

You need a 3rd party program such as Blender (free). You would need to select the parts individually and then export them, then re-import into UE.

Also check your mesh triangle count, to optimize use meshes with a lower triangle count, or look at lights if you use any, disable dynamic light from light sources for instance.

I have done all that, my scene only uses a lightsource and a skylight with a lightmassimportancevolume. the only thing i can see which is very heavy is when I use the shader complexity viewport, it shows that my trees are darkred and de fog in the distance is bright white (which is very bad I understood).

I dont know the triangle count, where can I find it?

Add a Cull Distance Volume to fade (cull) out objects in the distance. For trees use trees with max 10 maybe single trees with 20k triangles, everthing higher is not feasible, a normal tree can be optimized to around 5-8 maybe 10 k and still look decent. There are also very good trees with 2k triangles, blend them with higher counts.

If you go into a mesh view (double click a mesh) in the upper left corner is the number.

does cull distance volume work with painted foliage, because my scene has a lot of trees and grass. for the trees and grass I have set a culling amount each (in the foliage painting mode) which works quite wel for me.

ah i see, some of my cliffs in my scene exist out of more than 1.6 million vertices. need to tune that down a bit

Additional many trees (like with Speedtree) offer LOD levels when imported, but this can look a bit sad sometimes so i normally relay on culling, at least for isolated trees, besides the cull volume there is a cull distance option in each mesh (panel setting).

ah right, I have set the cull distance in the foliage editor under each specific object.

i can’t seem to edit the screensize per LOD, it is greyed out?

oh, nvm the screensize per LOD issue, solved it already :slight_smile:

how does the profiler for the GPU and CPU work, you can see which task is taking the most time to complete, but how can I find the source of the task so I can optimize it to run better?