Hello. This must be a common problem. I have a car model - consisting of multiple body panels, light covers etc. (each a thin shell - like in real life.) I would need to create a solid (filled) collision object. Obviously directly converting to SDF is not working - it tries to fill thin panels and not the inside and fails.
What are common methods (besides hand modeling) on solving this? (Couple ideas coming to mind would be some sort of voxel-flood-fill from the inside or wrapping a spherical mesh from the outside.)

Depends on how and where you want to use the asset. You might want to try Convex Hull (Shrinkwrap) or Convex Decomposition applied on the whole model or per piece. Using a combination of simple convex shapes, like boxes, capsules and cylinders is also an option.

DaVlas
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