Why is my mesh inversed when Imported to Unity? So I modeled this sword and all the parts were separate meshes. I used a mirror modifier when I was modeling and then I applied the modifier when I was done to make the parts into solid meshes.
Put a UV map on everything and it all looked good in Blender.

Then I put it into Unity and I got what you see in the picture. Part of the sword is inversed. Oddly, the inversed part actually maintains the proper silhouette. It maintains the correct shape, but then is shaded like the front half is missing.

Does anyone have an idea of what's going on and how to fix it?

Thanks,
James
One possible reason for this could be that the normals actually were inverted in Blender but if you have Backface Culling disabled then the mesh could look right even though it's not.  The lighting may look weird but the polygons will look like they are facing outwards.



Backface culling is an optimization that disables shading on polygons that are not supposed to ever be seen.  

When in Edit Mode, you can activate a tool that will show you which direction the normals are pointing in.  Just make sure that the size is adjusted appropriately for the model's scale otherwise you may not see them.



To correct the normals, you can use Ctrl+n which is also shown in the following image as a toolbar button labeled Recalculate.  

You can also selectively flip the direction of faces using the button labeled Flip Direction which can also be located in the Faces Menu Ctrl+f with the alternate name Flip Faces 



(The different names are a mistake, both use bpy.ops.mesh.flip_normals())