View Full Version : Open for Critiques - Squash & Stretch

12 December 2004, 10:03 PM
I'd appreciate your critiques on this squash and stretch exercise. It's a bouncing tennis ball.



12 December 2004, 11:11 PM
You really need to work on your timing and spacing. The motion is way too fast and unrealistic. The ball should slow down as it reaches the top of the bounce and speed up as it reaches the ground. It should spring up off the ground and slow down again and then gradually pick up speed before it hits the ground again and springs up, and so on. Ball bouncing is a great way to experiment with rhythm in your animation. It seems like the speed of the ball is constant here, ie. there is no rhythm. Check your arcs; they should resemble the McDonald's logo; round at the top and sharp at the bottom. The squash and stretch is a nice touch, though you'll want to exagerrate it much more once you work out the timing.

12 December 2004, 03:43 AM
I had to do this same assignment for a class of mine and my teacher said that the more you exaggerat, the more it shows you got the point. Are you going for realistic or are you just practicing? If you are going for a natural look, the timing is extreamly quick (I know how annoying that can be to get it down, I did a few different ones before I even got close) but if you are going for a cartoon look, try to exaggerate the motions, especially the squash and stretch part. Just have fun with it, make it look silly! Even if it looks like a cartoon, you will be able to prove you know how to do it. :)

12 December 2004, 08:40 PM
Thanks for the comments. I've made a second attempt based on GregRinaldi's comments. I thinks it's much better, but I would still like to know what I could improve on. (



12 December 2004, 11:19 PM
looking much better for second try..

I think you improve by (it is just theory..for me.)
*place little more hang time after second 2~4 frame..?
*do not go for DEAD STOP...It can roll off or tiny little bounce..
It looks like ball is stuck like magnetic..

frist bounce in 2nd try is "WOW" by looking at 1st try..
great improvement..

12 December 2004, 02:56 AM
Much, much better anvar. Sanghoon is right though, add a bit more hang time and some momentum at the end by letting the ball roll to a stop. When you finish this animation, you may want to try doing another where you treat the ball like a character. See what it would be like if the ball had a personality and bounced around on it's own. These excercises are great for practicing timing and spacing without have to deal with a complex character rig.

12 December 2004, 07:15 PM
I had a third try at this squash and stretch exercise. This time I tried to give the ball a little bit more personality. I also have some questions for you guys.

1. When animating a ball in 2D animation it is suggested never to transition from stretch to squash to stretch. Is this also the case in 3D computer animation? And wouldn't that mean that those keyframes would have to be back to back, all within a frame of each other (stretch-squash-stretch)? Because I don't know how to follow that guideline without doing it any other way.

I have seen some computer animations of bouncing balls where they transition from only squash to stretch. Is this a good idea?

2. Is timing a matter of trial and error and experience gained therefrom?

Here is the link to the third animation. (

thanks again,


12 December 2004, 08:40 PM
Your third attempt shows some real improvement, nice stuff.

There are two things that kind of stick out at me at this point - at the extreme "in the air" positions, when the ball is at the height of its parabolic trajectory on each bounce, there is some slight jerkiness in the movement. I think you can smooth this out using spline keys in the graph editor, but without examining your timeline I can't be sure that that will be enough.

If you're not familiar with the curves created by the program, this would be a great project to start learning them. If you're in Maya, select the ball and go Window > Animation Editors > Graph Editor.

If in MAX, go to 'Track View Selected'. Can't remember which menu item that's under (it's at the top of the screen towards the right-hand side). In the track view that appears there should be a button to show your curves.

The only other thing I notice....for your assignment, are you allowed to have the ball roll to a stop at the end?

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