Vertex Normals Issue [Bug?]

[indexofrefraction]

Hi,
I encountered an issue that i never had before and i'm not sure if it is Corona related.
I'm importing Steps from Solidworks with all geometry then having Normal Tags.
Now in Corona i get some meshes that render completely wrong!

See attached pictures :
#1 Ceiling Panel rendering wrong
#2 Ceiling Panel rendering correctly after having the Normal fixed by the old "VertexNormalTool" Plugin
Mesh Object (original / fixed) attached

It would be nice if it could be checked what is the issue here.
Geometry? Normals? Lights?

best, index
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[bnji]

Hello @indexofrefraction,
Thank you for commenting about this.
Actually, this issue is more common than you'd think.
It is related to how data for the normals is being exported to the exchange file format (STP, STL, etc.).
Usually, CAD and CAM apps use this data in a certain way, and the DCC app (3ds Max, Cinema 4D, etc.) interprets it differently.
The usual workaround for this is to remove the Normals tag from the imported objects, and if you still want some extra control over the object's normals, you can add a Normal tag again.
Another workaround for this is exporting your objects using the .OBJ file format instead of using .STP or .STL file formats.
I hope this helps.
Perhaps someone else has another interesting idea for this.
Looking forward to hearing from you.