Aerial physics help

[SharpBeast]

Yo sup peoples. It's Beasty.
Lets cut to the chase, as some of you might have noticed, my latest animations have weird aerial time in them(like in jumps, e.t.c.).
I have totally no idea on how should I fix this. So if someone here would be so kind and give me some tips 'n advices to fix this problem of mine I would be grateful. Also if it is not hard could someone make an example of proper arial time-spacing. I would love ya.
Peace..

[Caleb]

Basically you just need to know what momentum is. If you jump, the speed at which you leave the ground will determine how high you go, obviously. You can't just randomly create this momentum upwards. It needs to be built on the ground, because as soon as you leave the ground, gravity comes into play and there's nothing you can do to stop it since you're airborne. Also keep in mind, gravity controls vertical momentum and air controls horizontal momentum, meaning that the speed that your stick has sideways won't change much throughout all the frames where he's airborne. For this reason I always move my stick horizontally by around the same amount as last frame and only then do I move him up or down.

As for rotation, this is also mainly momentum. If you kick a leg into a certain direction and aren't standing on the ground, you'll keep rotating in the speed and direction you threw your leg in until it's stopped by something (usually landing).

So yeah, just gotta know your momentum.

[SharpBeast]

Basically you just need to know what momentum is. If you jump, the speed at which you leave the ground will determine how high you go, obviously. You can't just randomly create this momentum upwards. It needs to be built on the ground, because as soon as you leave the ground, gravity comes into play and there's nothing you can do to stop it since you're airborne. Also keep in mind, gravity controls vertical momentum and air controls horizontal momentum, meaning that the speed that your stick has sideways won't change much throughout all the frames where he's airborne. For this reason I always move my stick horizontally by around the same amount as last frame and only then do I move him up or down.

As for rotation, this is also mainly momentum. If you kick a leg into a certain direction and aren't standing on the ground, you'll keep rotating in the speed and direction you threw your leg in until it's stopped by something (usually landing).

So yeah, just gotta know your momentum.

Any good ways to find it? I mean I am struggling with it(if you have seen my animations then you know what I'm talking about), or some method to improve it.

[Caleb]

Honestly I feel like you just have to find this out by yourself. I don't have access to Pivot so I can't animate anything for you and even if I could it'd just be hocus pocus to you anyways. Just take your time with animation, I tend to play my animation with every frame I add to see if I didn't mess up. Also, when you're not great at animation yet it's better to add too many frames than to add too little. The more frames there are, the easier it is to screw up and so the easier it'll be to see how you should animate it instead (possibly with some CC from someone here). Also, don't shy away from tutorials here. There's a whole section devoted to it, so you might as well try and see if stuff helps.

[Gifgiff]

One other thing that can be helpful to think about is drinking fountains.



No really, drinking fountains are amazing. Check out that arc! It's the same sort of arc most objects will follow as they sail through the air. These arcs are so important they've got a name: parabolas. They're useful because, ignoring air resistance, the center of mass of any object will move in a parabola as it sails through the air.

Here are some more parabolas:


The center of mass of an object is the point it rotates around when spinning freely. A hammer's center of mass would be close to the heavy part:

A person's center of mass shifts around depending on their position, but usually it hangs around near the belly.


Make the center of mass of an object follow a parabola and space it like Caleb said (even horizontal spacing, but eased vertical spacing), and bam! Hand-made life-like physics.

(For the purposes of example, I cheated and made these animations in Blender so that they'd have good, consistent spacing. I'd never have been able to get the spacing that perfect in Pivot, but it doesn't need to be perfect to look good)

Here's what the spacing of these animations looks like:


...Of course, true-to-life physics can look pretty stale and uninteresting. As far as I can tell, what tends to look best in animation is usually not what the universe says is technically correct, but rather your own interpretation of what the universe does. A lot of personality can be packed into a bouncing ball just by changing the way it moves through the air. Still, I've found having a good sense of the spacing and trajectory of thrown objects in real life helps to keep things believable when you get stuck.


So basically, whenever I'm struggling to make a midair trajectory look right, I try to think about these sorts of things:
1. Everything Caleb said -- especially that gravity pulls down, not sideways, so it only affects vertical velocity.
2. Ignoring air resistance, every object's center of mass will move in a parabola as it sails through the air.
3. What looks good is probably not realistic, and that's fine

[Caleb]

^That's one of the best explanations on physics I've ever seen on here. Mind if I quote this and paste it to the tutorial section? I might add some things to clarify what you mean when you mentioned me.

[Gifgiff]

Sure! If you want, we could edit it a bit so it reads like a proper tutorial, too. Around halfway through making those examples, I realized the post was getting a little out of hand, so I was thinking of reusing the images in it for a tutorial anyways. Feel free to change any of the wording in it. We could make changes and send it back and forth a couple times in PMs, too, if you think that'd help.

[SharpBeast]

Honestly I feel like you just have to find this out by yourself. I don't have access to Pivot so I can't animate anything for you and even if I could it'd just be hocus pocus to you anyways. Just take your time with animation, I tend to play my animation with every frame I add to see if I didn't mess up. Also, when you're not great at animation yet it's better to add too many frames than to add too little. The more frames there are, the easier it is to screw up and so the easier it'll be to see how you should animate it instead (possibly with some CC from someone here). Also, don't shy away from tutorials here. There's a whole section devoted to it, so you might as well try and see if stuff helps.

Tut Section I've read it.(and I have watched Hyun's tutorials on animating too, even if they are in flash, they are still very helpfull)
I also tend to check on my animation every 1-3 frames to see if everything is ok(that is the reason my footwork is not shaky anymore).
I will try to find that out, but thanks anyway.