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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?
Hand animation never seems to capture the feeling of "weightiness" properly. The models just jerk around as if they had no mass or center of gravity. With motion capture, the center of gravity is always apparent, and the model doesn't seem like a hollow marrionette.
I used to bulls-eye womp-rats in my pants
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...
Well, that clarifies it. More lifelike, but lacking in life.
So it takes longer, but in some cases it maybe traditionally isn't longer, but it's probably not quicker. Other great quotes:
Actually, that is the entire point of motion capture: It captues the fluidity of the actor exactly.
If you can tell the difference either way, then the method was not implemented properly. There is no "is one better than the other?" there's only "which is best for the job."
Consider this: If you want to use mocap, but it causes wiggly meshes, then you have an implementation problem. Do you write the code or adjust the model/actor to solve it, or do you use the video as reference and manually keyframe it? Do you even care? Will the gamer care? Is it worth the money?
I realize this isn't exactly a either/or type of discussion, but it will quickly turn into one. One guy will have seen bad mocap, another will have seen bad keyframing. Done right, either technique will be extremely convincing. It's fun to discuss, but let's keep this out of the realm of absolutism.
"Derp de derp."
Who says motion capture has to be disjointed and separated? If you insert appropriate animations between different captured actions, the result could look very smooth. Just because many games have crappy motion capture doesn't mean the technology is flawed, we are just waiting for someone to do a better job.
No matter which technique you choose, there's going to be some degree of animation involved. To make it look right, most often a hybrid approach can yield the best results. 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? It can't be done accurately with motion capture, but you can use motion capture along with traditional animation techniques to create realistic looking physical movement. Or take gun recoil-- motion capute is probably going to produce something very realistic, but using that data verbatim in a game engine will likely result in poor playability. Animation fills in the gaps.
I don't really see what the argument is about here. There is plenty of work for both the motion capture proponents and the animation proponents!
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.
I have seen tehcnology which makes a character walk realistcially using just a neural net controlling the system through genetic evolution. And 15-20 years ago they were able to create a stick figure which always maintained it's center of balance whichever way you attempted to move it.
Surely we have the technology to create a system where we can tell a character to go move from point A to point B, while ending up in a pose similar to a specified pose, all with algorithms. This would result in the smoothest and most realistic animation, and with proper "key frames" you can still define end poses which you want the character to try to end up in so that you can make artisitcally intersting motions. In theory if you had a system like this would be able to make a character limp and drag their leg, or crawl along the ground dragging both legs with their arms simply by telling them to move towards a point by whichever means they can and shutting off the apropriate bits of their body.
This of course is not the simplest thing in the world to implement. Someone needs to start a company to implement this technology into a library which you can just plug into your game.
If you want the best example of hand animation looking good on real people, check out any of the wrestling games made by Aki, especially the WCW vs. NWO games on N64. Compare that to something like Smackdown for PS2, and it's still 100x better.
Hey Tecmo, care to bring back Tecmo Super Bowl with hand-drawn animation? I think it would make a football game move much better. Developers need to shoot a LOT of mocap data to make it look better than now.
I'm on top of my game like I'm standin' on Xbox.
Remember that a lot of animation is done with motion capture these days... such as Gollum in LOTR - and most people agree that Gollum is one of the best pieces of animation around!
Robots are everywhere, and they eat old people's medicine for fuel.
Check out Splinter cell for the xbox or PC. ALL of the animations for Sam Fisher were not done with mocap. Everything was had drawn and animated and it looks perfect. This isthe type of game that I would have expected to see a great deal of mocap (lots of character movement in different areas) but instead they managed to make a game that's fun to play and visually innovative in the fluidity of the character movements.
Looking at games like MGS2, motion capture doesn't seem at all necessary. That game had fantastic animation, especially in the cinematics. Same thing with Splinter Cell, Jak and Daxter, and numerous other games. The only possible reason I can see for motion capture is either as a marketing gimmick (as it was with Enter the Matrix). I guess that motion capture is better if you're basing a game on a movie, so you can catch the subtle mannerisms of the actors (assuming they agree to be featured in the game at all).
Kaydara makes an animation package supporting all the major file formats (Maya, 3ds, XSI, Lightwave) and is meant to do only one thing, which it does really well : animating your characters. It's also one of the really good motion capture packages. It has motion blenders, inverse kinematics, the works. I've seen this software run and it's really amazing. You can take the skeleton of a 4 foot monkey with long arms and map it to a tyranosaurus rex who has little arms for example and the animaton will scale realisticly and with minimal effort. You can even put your own keyframes over the motion captured data and the when you have finished keyframing a small portion of the animation you can have it blend back with the original motion captured data, so the animation is never disjoint.
...Aside from the aesthetic benefits of animation over straight mocap, many animators these days are hurting for work :P
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.