GoldSrc

GoldSrc (also known as Goldsource) was a game engine used internally by Valve Corporation. It was a heavily modified Quake engine that debuted with the release of their science fiction first-person shooter video game Half-Life. The engine also powered future titles developed by or with oversight from Valve, including Half-Life's expansions, Day of Defeat, and multiple titles in the Counter-Strike series.

GoldSrc was eventually succeeded by the Source engine with the releases of Counter-Strike: Source and Half-Life 2 in 2004.

Development

The basis of GoldSrc is the engine used in the video game Quake, albeit with heavy modification by Valve Corporation, at the time called Valve Software. While the engine served as the basis for GoldSrc, Gabe Newell has stated that a majority of the code used in the engine was created by Valve themselves, not taken from Quake. GoldSrc's artificial intelligence systems, for example, were essentially made from scratch. The engine also reuses code from other games in the Quake series, including Quake World, and Quake II, but this reuse is minimal in comparison to that of the original Quake. In 1997, Valve hired Ben Morris and acquired Worldcraft, a tool for creating custom Quake maps. The tool was later renamed to Valve Hammer Editor and became the official mapping tool for GoldSrc.