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Hoaxer: What kind of shadows are used in Source engine - are they fully dynamic, or are they partially static lightmaps - do you use a combination of lightmaps and dynamic shadows?

Gabe Newell: We use a combination of dynamic and static lighting. Objects that move cast dynamic shadows whereas static objects cast, well, static shadows that are cheaper. On DX9 you get soft dynamic shadows as well. We also have a full radiosity solution for static bumped lighting (bump maps work with static lights). If you were to put a static light next to a bump-mapped object, the light direction would be correct (traditionally light maps and bump maps have been mutually exclusive).