S.T.A.L.K.E.R.: Clear Sky
, is the stand-alone prequel to Stalker: Shadow of Chernobyl
, a first-person shooter computer game
by Ukrainian developer GSC Game World.
The game consists of a roughly 50/50 mix of new areas and old, remodelled areas from the previous game. The X-ray graphics engine has been updated to version 1.5 and includes DirectX 10
support (later patch 1.5.06 included DirectX 10.1). Additionally, the AI received an overhaul to accommodate the new faction wars feature.