TechnoClass::Unlimbo assigns SightIncrease = Get_Sight_Bonus(coord) from the caller's coordinate (code/techno.cpp:1742 as of ecd2968). Structure placement passes a bare cell — building->Unlimbo(cell) on deploy in UnitClass (code/unit.cpp:1947) and tech->Unlimbo((Cell)cell) in HouseClass::Place_Object (code/house.cpp:2753) — and Coord(Cell const &, LEPTON z = 0) (code/coord.h:61) gives it Z = 0. By then ObjectClass::Unlimbo has already run Coord_Fixup, which sets PositionCoord.Z to the ground height (BuildingTypeClass::Coord_Fixup, code/builtype.cpp:1615), so a structure on raised ground ends placement with a bonus of 0 while its own coordinate says otherwise.
The only reader, TechnoClass::Look (code/techno.cpp:7940), recomputes the value from Get_Coord().Z before using it, so no reveal radius is wrong. The effects are that the structure's first look after placement is forced non-incremental (the recomputed bonus exceeds the stored 0), and that the stored value serialized into saves and the desync dump is wrong for every structure on raised ground.
Seeding from PositionCoord — SightIncrease = Get_Sight_Bonus(PositionCoord); — or dropping the assignment, since Look() rewrites it, fixes both. Units are unaffected either way: their per-cell look rewrites the field.
TechnoClass::UnlimboassignsSightIncrease = Get_Sight_Bonus(coord)from the caller's coordinate (code/techno.cpp:1742as of ecd2968). Structure placement passes a bare cell —building->Unlimbo(cell)on deploy inUnitClass(code/unit.cpp:1947) andtech->Unlimbo((Cell)cell)inHouseClass::Place_Object(code/house.cpp:2753) — andCoord(Cell const &, LEPTON z = 0)(code/coord.h:61) gives it Z = 0. By thenObjectClass::Unlimbohas already runCoord_Fixup, which setsPositionCoord.Zto the ground height (BuildingTypeClass::Coord_Fixup,code/builtype.cpp:1615), so a structure on raised ground ends placement with a bonus of 0 while its own coordinate says otherwise.The only reader,
TechnoClass::Look(code/techno.cpp:7940), recomputes the value fromGet_Coord().Zbefore using it, so no reveal radius is wrong. The effects are that the structure's first look after placement is forced non-incremental (the recomputed bonus exceeds the stored 0), and that the stored value serialized into saves and the desync dump is wrong for every structure on raised ground.Seeding from
PositionCoord—SightIncrease = Get_Sight_Bonus(PositionCoord);— or dropping the assignment, sinceLook()rewrites it, fixes both. Units are unaffected either way: their per-cell look rewrites the field.