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- The first step is to make sure your model consists of 1 smoothing group. It also helps to triangulate your model using a modifier, that way you do not have to worry about any application changing your triangles.
- When exporting your lowpoly model for xnormal using these settings:
The important points are smoothing groups, and tangents & binormals
- When loading your lowpoly model into Xnormal make sure Use exported normals is enabled.
- After baking your normal map, export your low poly models for Unreal using the SAME FBX settings as before.
- When importing your model into Unreal, enable Import Tangents and Explicit Normals