Resolve the effective ObjectStyle for an IFC type, merging user overrides on top of the built-in defaults.
Resolution order (highest priority last wins): _default → per-type default → per-type user override
Optional
Resolve the effective ObjectStyle for an IFC type, merging user overrides on top of the built-in defaults.
Resolution order (highest priority last wins): _default → per-type default → per-type user override