Cards leaves, Lighting (normals) adjusted.
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Hey PowerDesign,
I can assist you with your issue, but seeing as how you are using an external application that has their own support as well, I would also refer yourself to the SpeedTree documentation found below to make sure you are taking all the correct and required steps before importing your model into the engine.
Working with SpeedTree in UE4
http://docs.speedtree.com/doku.php?id=ue4_introduction
If you could provide me with some simple steps so I can reproduce the issue on my end, we can go from there. More specifically, the type of leaves you added to the branches (you mention card leaves) but are these camera facing leaves, and/or do they have an added mesh to them (cross-foil, tri-foil, plane etc.).
I will also need the import settings you are selecting when importing your tree into the engine.
Cheers,
Hi Andrew, I also posted it to SpeedTree forum.
Oh, for this model, the results are the same in 4.8 and 4.6. But we do have other models showing difference between 4.8 and 4.6.
The difference between SpeedTree Modeler and UE4 is because UE4 displays the normals at the positions of the vertices before applying the facing shader. ← Not really valuable as normal visualization.
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Finally, I found this is due to the new Use MikkTSpace Tangent Space checkbox defaulting to checked.
Glad you were able to discover the correct answer!
I marked your answer as resolved, and thank you for supplying the answer in your response as it will help others who are experiencing the same issue find the correct resolution.