View Full Version : Billiard Balls

05-06-2008, 08:10 AM
I've got a dynamics question. I am trying to animate the classic pool ball break and I'm running into some issues. The ball break is working ok but I'm having trouble getting the balls to interact with the table. How do I get the balls to stay flat on the surface of the table and to bounce off the bumpers in a realistic fashion? Do I put collision objects on each side of the table?

If you know of any tutorials on this that you can point me to, it would be much appreciated. Thanks for the help.

05-06-2008, 09:39 AM
What is happening to the balls? Are they falling through the table? It should be pretty basic to get them to bounce off of the walls. You can make 5 collision objects set to plane (flour walls and the table) and make sure your balls are set to sphere on collision. That is going to be a lot easier of a calculation than the mesh itself. I'm rendering right now or I'd do a little test on it but I think you can set it up that way and be in the ballpark.

05-06-2008, 09:53 AM
Expanding on what Surrealist said, you may want to set the four bumper walls to Bounce, and set the ground plane to Stick. Having the ground set to stick should keep the balls to stay flat on the surface.

05-06-2008, 09:54 AM
The issue I am having right now is when the other balls start to move, they dip a little below the table surface and then come back up to their initial level (see attached). I've finally got the beginning of the break to look the way I want it minus this dipping problem.

Would you have the billiard balls each on their own individual layer or all together? I currently have them on one layer.

I'm fairly new to dynamics, I don't get to use them too often so forgive my ignorance.

05-06-2008, 10:19 AM
One other issue I am seeing is that the balls keep spinning even when they have stop moving. How do I get that to stop? I just hate it when my balls spin!!

05-06-2008, 10:55 AM
I would think separate layers would be good. Now I think they are being calculated as pieces it seems. That might be why they are dipping. There is a way to get them to stop moving too.... in the middle of a render again and I don't remember the setting.... sorry. But set each ball at center and you can change it from pieces to a whole solid object for each ball. Someone else can chime in but I think that might be better.

05-09-2008, 07:27 AM
Just an update. I was about to give up on the balls being on one layer and seperate them out when the Dynamics God decided he had toyed with me long enough and allowed me to get the effect I was going for. I've got the break to work with all the balls being on one layer and I also got them to stop spinning when they're not moving. Just used the hunt-and-peck method with the settings till something worked.

Thanks for the help Surrealist and BlueApple :beerchug:

05-09-2008, 08:27 AM
Ah...good. because I finally got a chance to play with it and realized I did not know how to make each ball work as both a collision and a hard Fx object. There must be a way. And I guess you discovered, stop by stabilizer. I think that is the setting to get them to stop...

Do you mind posting the settings or the scene? I am curious what you did to get it all to work.

05-09-2008, 09:17 AM
I used just hardfx on the cue ball and the other balls without a collision. I did the same thing as you first with the collision and hardfx but could never get it to work. Anyway, take a look.

I have to admit my ignorance. I haven't attached a scene/object to a post before so if it doesn't come through right feel free to call me an idiot and I'll try to repost.

05-09-2008, 10:09 AM
Thanks for that. It opened fine. Looking at it now.