Both Sci-Fi, yes... Both FPS, yes...
However niether need high-end PC's (unless you want to run at full graphics, even then Doom3 isn't any more demanding that Halo)
So how are they different?
Stories are completely different for one,
In terms of films, Doom3 would be Resident Evil or Project Code 24
Half-Life2 would be Stargate, or Star Trek.
The differences being that although HL2 is more real world set, the actual dynamics of the game edge more towards the scifi; whereas Doom3 has elements of scifi but is relying more on the horror side of things.
Secondly is the graphics engines, HL2's is very much designed for realism ... Doom3's is designed for Atmosphere.
You then cometo gameplay, HL2's is an evolution or rather a single step up from Half-Life. Doom3 is again built for atmosphere, to give the player a sense of being chased and anxious all the time. (however Valve and id always have had EXTREMELY different playability engines, now it is far more apparent)
Next up is the Level detail, although HL2 has destoryable terrain which is interactable with the physics engine; makes a nice touch. Everything for it has to be pre-scripted. Which means the levels are only as interactable as the level designer makes them.
Which also means although the world seems complete and fully interactiable, your still doing a PointA->PointB style of challenge gameplay. The new Chapters setup does give you a little freedom from this, but still the game is 100% linear.
Doom3 on the other hand is a fully interactive world. Yes, you have mission objectives, but the route you take is completely upto you as the player. Also the only things scripted ingame are the cutscenes; those bits your see of the creatures bursting from the walls, that had nothing to do with the level design or anything like that. Those creatures have either tracked the player til they think they can attack safely else just heard them and decided to make thier own door.
Sorry but the main reason i think HL2 and Doom3 are different beasties is that ID Software has tried to make Doom3 and evolution on thier previous titles and give the player as awesome a single player experience as possible.
Valve on the other hand have just added to thier Half-Life formula hoping that the "if it ain't broke, don't fix it" saying is true.
you want to know what Half-Life2 is like there are many places sporting the HL1.5 engine exe which will upgrade HL with the Source engine. Sure the new polycounts and animations make HL2 nice and all; but really HL2 is all superficial.
Doom3 is the one thats gone from superficious violence and a reason to just blast at anything that moves to a game with more depth than the atlantic ocean.
id software have really tried their best to bring to the table a title worthy of carrying the name Doom3; and just watch the trailer again, don't look at the graphics, look at what it's showing you as part of the game. And remember no scripted game events; it is an OPEN GAME.
Doom3 is exactly what i'd hoped Space Hulk would be when i started it 3years ago... as i'm finally nearing the completion of my game, only another 8months to go with it if all goes well; i just hope it can be half the game that Doom3 is. The player is finally playing the game rather than playing a linear story with action.
sorry but that excites me, but i guess to most of you HL2's glitz seems far better.
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