The light derives its direction from the owning GameObject's
transform (local -Z). On load this legacy field is folded into the object's
rotation (see migrateLegacyLightDirection in instantiate.ts) and is no
longer written back out. Retained only so pre-migration scenes still load
with the correct sun angle.
Deprecated
The light derives its direction from the owning GameObject's transform (local -Z). On load this legacy field is folded into the object's rotation (see
migrateLegacyLightDirectionin instantiate.ts) and is no longer written back out. Retained only so pre-migration scenes still load with the correct sun angle.