'General'

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"Pose to Pose Pop-Through Animation" by Keith Lango


Kill Mr. Roboto!
Here's where things get a little less formulaic for me and I start to rely on experience and a good eye for animation. The deleting of keys.
Many a young animator struggles with having too many keys. Especially if they're just going straight ahead. After awhile they don't know what they're looking at anymore (at least I didn't back then). The solution for me was to key smartly. But in the pose to pose world, the problem is it can be TOO organized, things can be too structured. What's needed is some good old fashioned editing.
I try and look at the spine mostly. I found that alot of the rigidness in my work comes from the spine being too tight.
So I'll go in there and shuffle things around, deleting keys and some breakdowns here and there. I'll also try having
a lower spine control not settle into the pose until almost near the end of the hold.
Sometimes I'll have the head take longer, or somesuch. This is the massaging part of animation that is very difficult to define as a step or a process. So here's a look at a close up of the dope sheet and the corresponding animation change that goes with the edit.
It's a very subtle effect, but when you do this for the whole shot, it really starts to loosen things up and defeating that robotic feel. And remember, this is still all with linear keyframes. There's no ease in or ease out from key to key. The plus side of this is that when the time comes to start adding ease in and out by switching the fCurves over to spline interpolation and then filtering the tangencies, you're not in for any surprises. Oh, one last thing here: I took the time to really tweak the whole hip/weight transfer flow in the part where he kicks the fallen tablet out of the way. This again is something that you just need to use your animator's eye to spot and fix.
This is the place where I try to address anything that really needs fixing, before going into spline curves.
F-Curves, away!
Now I'm ready to switch the fCurves from straight linear interpolation to a spline interpolation with edited/filtered curve tangencies at the keyframes. Here's a quickie peek at the curves for one control object...
What this is going to do is really smooth out alot of the remaining jerkiness of the animation. Pose hits have ease to them, transition breakdowns have some flavor besides straight through. There's no surprises here, I'm not really adding anything new, but I'm taking what I already have and applying this neat smoothing to it all.
It's like icing on an already pretty tasty cake. The trick is to not violate the extremes as they have been defined already. Spline interpolation by default tends to overshoot the holds, really making things sloppy. So I try and keep the holds pretty tight with a minimum of overshoot, while the keys in the middle transition areas are pretty smooth. Now if I wanted, I could go through each control object and delete select keys in the middle of curve transitions to make things smoother, and I may yet do that for this piece. Generally if I want to loosen things up even more I'll do it in the fCurve editor by deleting some frames along the curve that are hitching the motion a little bit. Still, if you want the absolute best animation you can get, then that's a step worth taking in my opinion. Like I said, I didn't do that for this piece as it is seen here.
Update: The statement directly above is especially true when you want to get even finer, more natural motion. In taking your work from serviceable to excellent in quality, you're going to spend at least half your time in the finessing of the keys and curves. Yes you can produce OK animation by doing everything up to this point, but you'll be leaving the work short of all it can be by not going the final mile. You can expect to spend 50% of your time on the last 15% of the animation to bring it to a level of excellence. Now if your producer/employer states that the budget doesn't support that level of quality, then you'll have to leave that undone and live with what the preceding efforts give you as far as results. But for your own work at home or for your portfolio and personal growth I highly recommend spending the time it takes to generate the absolute best animation you're capable of. Employing that level of discipline will best serve you in the end.
Here's the motion with the spline ease curve interpolation...
The animation of the body is pretty much done here. Like I said, I could go in and tweak it more. Since this is a personal clip and not for work, I may. That's the nice thing about personal pieces, no deadlines and no quotas. Well, sometimes no deadlines. I did 3.25 minutes of animation in 7 weeks for my short film "Lunch". As you can see, THAT had a deadline and this method helped me meet it. :o)
Comparison Shopping
For the ultra curious, I have made a side by side comparison of the preview animations as they progressed. The way it works is this:
pop1 vs. pop2
pop2 vs. Linear
Linear vs. Cleaned Up Linear
Cleaned Up Linear vs. Linear Offset
Linear Offset vs. Splined Curves
Splined Curves vs. Final Animation