Shading in valve's source engine

Abstract

Starting with the release of Half-Life 2 in November 2004, Valve has been shipping games based upon its Source game engine. Other Valve titles using this engine include Counter-Strike: Source, Lost Coast, Day of Defeat: Source and the recent Half-Life 2: Episode 1. At the time that Half-Life 2 shipped, the key innovation of the Source engine’s rendering system was a novel world lighting system called Radiosity Normal Mapping. This technique uses a novel basis to economically combine the soft realistic