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When I imported this model into Unity a few parts of the model seem to be inside out. (the wings and the left engine)
I opened the model in blender, selected the relevant components, and recalculated normals. Now nothing is inside out.
However you can see that those parts are now really dark. And I can't fix this.
The problem itself can be seen in blender as dark faces. Similar to the problem seen when faces are inverted.
I have already tried:
recalculating normals on all components (the rest are unchanged)
checking that the normals actually ARE facing outwards by showing the weights of the normal
checking that both parts share the same material
why are these faces darker? how can I fix it?