Converting RGB object space normal map to tangent space normal map

Development Asset Creation
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Hey peeps! Trying to do a object space normal to tangent space normal conversion in Unreal 5. This youtube video by Cody Gindy illustrates the process. - Making 3D animation look painterly (it’s easier than you think) - YouTube

ObjToTangSpace
ObjToTangSpace1786×714 173 KB

I’ve been able to paint the object space map… but the conversion in UE is killing me - you notice the crazy artifacts in the images. Tried a few simple things… any help would be greatly appreciated!!

I’ve found this formula Tg→ N = 0.5 + [ Tg→ ⋅ N → o b j (N → × T g →) ⋅ N o b j N → ⋅ N → o b j] / 2

And attempted to replicate it through the mat editor… not great at math here…

ObjToTangSpaceTry3
ObjToTangSpaceTry31784×507 129 KB

Help?

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Hi i am having the same problem did you have any luck with it?

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No unfortunately. Still looking about. Was hoping someone from Epic would chime in on it.

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oof

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Hi there! I have found that using xNormal to convert the world space to tangent space has been pretty effective. What I have yet to find a solution to is how to handle flat surfaces. Nothing seems to like adding any sort of color variation to the world space normals when trying to convert to tangent space.

xNormal has a tool that allows you to select your mesh and the world space normal, and use these to convert your texture map to tangent space