The Animations: Any other game I've seen don't quite come close to the animations of doom3
Actually, the HL2 animation surpass them. And yes, I'm stating this as fact. Not only does valve use a muscle system, which provides more realistic detail in both movement and facial expression, but they have also detailed the animation and models right down to the eyeballs.
personally I think Carmacks goal with doom3 is to take gaming a step closer to CG Movies (a'la shrek, toy-story, final fantasy, etc)
They certainly got the unrealistic plastic "sheen" problem down pat.
As a matter of fact id stated themselves that they used motion capture for the 'human' actors ingame.
Motion capture is industry standard, and humans only account for about 5% of the NPC's in D3 in any case.
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