Speedtree: Using custom srt LODs

Development Asset Creation
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Greetings,

This is my first question so apologies if I posted it in the wrong place or something.

So say I made a tree in Speedtree ue4, and I used individual leaves as opposed to a plane with branch/leaves texture on it,
Obviously the model ended up being too heavy, and I have around 200k tris on the leaves alone, the LOD settings in Speedtree removed only about 20k which is clearly not enough (especially if I was planning to make a forest scene or something)

So I looked up solutions, and I tried the following:

  • Using the “Simplify” option in speedtree: which got me to a great result, but it’s pretty much similar to using a branch/leaves texture on a huge plane, which I try to avoid.
  • Increasing the LOD settings in Speedtree: including leaf collision (which removes leaves that are too close in proximity), model was still way too heavy
  • Using LOD on leaves: which removes leaves the smaller the model is in screen size whilst increasing the size of the surviving leaves, that option is not ideal, the amount of leaves I need to remove to sustain a playable scene makes the size of the other ones enormous.
  • Adding a mesh LOD in Unreal within the static mesh editor: the problem here is, it seems to only import fbx and obj files, which I don’t possess.

So ideally, what I tried to do is make a high-poly tree model, add 2 LODs, simplify said tree in Speedtree turning individual leaves into a plane mesh with textures generated in Speedtree, export that as srt, import it as an LOD mesh; Problem solved: Christmas.

So to summarize TL;DR-style: Is there a way to use other trees as LOD meshes in UE4 and/or any other way to turn single leaves to frond textures ?

Thanks in advance,
**

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I actually found a MUCH simpler answer to my question than where I was headed.

To anyone concerned, Speedtree actually does this for you using billboards. what this does is it saves a couple of pictures of your tree (this happens automatically, no need to even simplify in Speedtree), then it adds the images to the 3rd LOD level with a 3-plane mesh (so it basically looks good from all angles).
So all you do is check “Both” where it asks you to import “Mesh” or “Billboards” whilst importing the tree.

You can also change the distance that LOD appears in UE by going to the static mesh editor, checking off “Auto-compute LOD distance”, then changing the “Screen Size” in the LOD you want to change, and there you go.

I would also suggest using “Leaf collision” in Speedtree if you have loads of leaves. use “spread then cull” if you want to roughly keep the same amount of leaves, and “cull then spread” if you want to reduce tris and/or leaf amount.
There are lots of other very useful settings there, so I’d check them out if your tree’s too heavy.

Have fun making trees !

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This is great news RamJ, thanks! I am actually trying to figure out the LOD/Speedtree/UE workflow at the moment with the latest speedtree and it seems to have a couple different options.