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Motion Capture Or Animation For Games?
Thanks to TotalGames.net for their article discussing whether videogames should use traditional animation or motion capture to capture the movements of in-game characters. The piece points out: "One of the major problems with motion capture is the way that moves can sometimes appear disjointed and separated, as a character goes from one set of moves to another", but an advocate for motion capture comments that the process is "..a lot faster, as long as you can retain the subtleties from the point of motion capture to the raw data to the point where it reaches the engine." Can you tell the difference?
I dont want to play Mario and watch some actor whos been digitally captured, I wanna see some goddamn animation.
Likewise, I don't want to play Manhunt and see animation, then I want motion capture...
If the animator is any good, the sense of gravity and weight is much better in models animated by hand, rather than motion capture.
Motion capture will always look more realistic, but so far there is a severe lack of animation skills in the industry. Mark of Kri and Jak and Daxter (both for PS2) are the only games I can think of off the top of my head that have well done character animation by hand.
In the end it comes down the type of game you're creating. You would never give a colorfully animated character a motion captured animation set, and giving realistic people exaggerated animations would give the game an entirely different tone.
"Motion capture is fine and good, but what about when you are trying to model the movement of a 50-ton 20-foot tall rock monster or something?"
You use a poor-man's motion capture. You video tape an actor (or a creature?) and anlyze its movements. How many frames does it take a step? What frame does it shift its weight?
Walking with Dinosaurs comes to mind. I watched the making of it, and boy was that cool and insightful. They had these birds that were kind of like pterydactls(sp?) with features similar to bats. They did kind of a four-legged walk with their hands located at the mid-joint of their wings. They had a terrible time animating these guys because they've never seen a creature here on earth that does that. So, eventually they figured out that a guy using crutches walking like a four-legged animal worked quite well. They didn't mo-cap it (that I saw) but they did analyze the vids frame by frame.
Another example popped into mind: Monsters Inc. Got the DVD? Watch the making of it. You can see a guy walking on a treadmill with cardboard tubes hanging from his arms. He was acting like a monster who's arms were really really long.
Yeah I know you weren't quite looking for the answer to this, but what they do to figure these problems out is amazing.
"Derp de derp."
There's actually been quite a bit of research to do motion blending so that the transition between states are not noticeably unnatural.
So the real answer is, it's not a limitation of mocap, but current application of the technology.
When you fell, you fell like a 600 pound man:)
"Another World" did the motion capture thing right. Also "Flashback" (both done by the same company) had good motion capture too.
There's a place for both in games I think. Motion capture is great, and a must for 3D games, but hand animated sprites still kick all kinds of ass in the right games.
Depends on what you're doing, actually.
With Rainbox Six, for example, they took a man, punched him *really hard* in various spots with a pole, and recorded him falling down. That simulates being shot.
The problem with this, or course, you see in games like Splinter Cell; Sam's running, or jumping, or rolling, or shooting. But he can't really run into a jump, miss, land, roll into a shooting stance and start peeling off rounds.
But nowadays, with tons of processor, and a good physics model, it can be just as good to build your models properly, and let the engine figure it out. Terra Nova: Strike Force Centauri, Die By The Sword (I believe) and Oni, for example, played with this early on; Unreal Tournement 2003 seems to be the current champ.
Myself, for video games, I'd avocate using mocap to more accurately build your models and tweak your physics engine, then let the engine actually do things. When my model's running up a hill, I want to see him leaning forward to place his center of gravity. When he gets shot, I want to see him fall back, then down, then start rolling down the hill. When he's lying on the ground, I want to see his arm tracking where I'm aiming; I want to see him use his other arm to lift himself up off the ground.
Vintage computer games and RPG books available. Email me if you're interested.
As has been pointed out elsewhere, there's a lot of good research on how to combine both. However, the key issues in choosing a method are:
Animated characters move in non-physical ways. A character can turn its head left to right in one or two frames. A human can't (without injury) and that puts a hard limit on mocap's usefulness there (except, see below).
Assuming you want realistic human motions, using a realistic human as model is essential. This can be a living human or a high-quality biomechanical software model driven by an animator or an algorithm. The latter is more interesting, since it allows more than just recombinations of recorded motions.
The main thing missing in motion capture, IMO, is real-time feedback. I worked on a system that used only 12 6DOF body sensors (magnetic, long time ago), but allowed you to drive an animated character in real-time. The effects were really good, IMO, in that the actor could adapt the way a puppeteer learns the motions of her puppet.