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Vendetta
02-06-2010, 05:12 PM
I'm animating in flash again, and I'm trying to make some one jump forwards off a building. After the first frame in the air, I'm not sure what to do. Does he slow down and then start falling normally? Or does he immediately start falling? Obviously, if he was jumping up, he would start slowing down as he got higher, and then fall. Whatever I try, it always turns out terrible looking. Can anybody help? it might be kind of confusing, sorry.

Bonk
02-06-2010, 05:52 PM
. . . . . . . . . . .o .^o o
. . . . . . . . o . . . . . . . . o

. . . . . .o . . . . . . . . . . . . o

__o__o
. . . . .| . . . . . . . . . . . . . . .o
. . . . .|
. . . . .|
. . . . .|. . . . . . . . . . . . . . . . o
. . . . .|
. . . . .|. . . . . . . . . . . . . . . . etc

the ^o means that that position is slightly above where the ^ actually is

Anyway, if the diagram doesn't help then know that if the animation is realistic, the decent will be smooth; a few frames of up, one or two of lingering at the peak, and then aggressive easing for the fall. For a more cartoony animation, the linger will last longer and then the guy will start falling very fast from this peak.

And if you still aren't happy with it, post the swf.

Vendetta
02-06-2010, 05:55 PM
ok, thanks

Tork
02-06-2010, 06:11 PM
on earth the gravity is 10 meter every second.
wich means every second the speed of a falling object on earth, would increasing 10 meter every second.
so right at the point it starts falling, it falls at zero meters every second
one second later, it falls 10 meter every second, 2 seconds after it dropped, it falls 20 meters every second.
hope this helps :)

EDIT: lol, sorry i just read your post again, and i just noticed hes jumping forward.. oh well, sorry :P

Überschall
02-07-2010, 09:42 AM
Still kicks into effect though, there has to be a point where the force of his upward jump and gravity reach equilibrium, so there would be a frame where he's still in the air. After that, the 10m/s² kick in, until he reaches a point when falling where gravity and air resistance equal out, so his speed doesn't increase anymore.

Zed
02-07-2010, 10:07 AM
http://i771.photobucket.com/albums/xx353/Zed31415/SuicideJump.gif

I'd say the best thing you can do is get the positions you want him to be in right first and then try to place him in the right place along the path Bonk described afterwards. He needs to go up fast, up slow, nowhere, down slow, down fast. Play around along those guidelines until you have something that looks about right.

Vendetta
02-07-2010, 12:26 PM
Okay guys, I think I just had him positioned really wrong. Everyone's help is greatly appreciated!

Brownoser
02-07-2010, 12:37 PM
quick 30 second animation for basic jump physics (minus the 'blob effect')

http://i48.tinypic.com/k4xnab.jpg

edit: ahh i posted it 10 seconds to late

Miccool
02-07-2010, 12:56 PM
The horizontal component will stay constant as gravity only affects the vertical component. So....

Horizontal component will change like this:
o--o--o--o--o--o--o--o--o--o--o--o--o--o--o--o--o--o--o

And vertical will change like this
o------o-----o----o---o--o-o-oo-o-o--o---o----o-----o------o

Vendetta
02-07-2010, 02:51 PM
I see, that makes sense. So after he jumps there should be no easing at all? When he starts to fall downwards is when I start to speed him up, right?

Zed
02-07-2010, 03:04 PM
Nonono. Up and down there is easing. Side to side there is not. If you like you could do the two parts separately. He goes up a lot, he goes up a bit, he stops, etc. But all this time he is moving sideways at a constant speed.

Miccool
02-07-2010, 04:10 PM
http://img24.imageshack.us/img24/9509/physicsconcept.gif

Scarecrow
02-07-2010, 11:31 PM
actually horizontal motion should gradually slow down as long as not force is being applied to it. it's due to friction with the air

Miccool
02-07-2010, 11:40 PM
Yeah, but that doesn't make any observable difference really....

Scarecrow
02-08-2010, 12:12 AM
not usually, but sometimes it just looks odd without it

Tork
02-08-2010, 01:12 AM
here, you might want to check this guy out,
http://www.youtube.com/watch?v=3KSr1pozm6Y
eaah, you never thought of that, eah! :D
good luck <3