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The Source Engine is Valve Corporation's current game engine, which debuted in Counter-Strike: Source. Since then, it has had many improvements with the release of subsequent games, such as the addition of advanced facial animation in Half-Life 2: Episode One, and better support for cinematic-style animations, shadows, lighting and long rendering distances in Half-Life 2: Episode Two. One notable addition was that of HDR and bloom support with the technology demo Half-Life 2: Lost Coast. Support for soft-particle physics was added with the release of Team Fortress 2.

[edit] Origins

The Source engine was built on top of GoldSrc, Valve's previous-generation rendering engine, which was itself based on the original Quake engine, with some changes from the Quake II engine incorporated. Source was mainly developed after the original Half-Life was released, and once ready, Valve's internal projects were slowly transitioned to the new engine.

[edit] External links

• Developer wiki