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jimiclaybrooks
05-02-2018, 07:22 PM
141502 I"ve tried rather unsuccessfully to get these pool balls to act like real pool balls. They don't roll when struck by the cue ball. Any help with this would be much appreciated. thanks

GraphXs
05-02-2018, 07:48 PM
I just tried with some layout objects and it seems to work. Attached sample test. Maybe it could be the size of your objects?

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jimiclaybrooks
05-03-2018, 03:29 AM
Thanks GraphXs, but I'm in LW 2015 so I can't open this file. I do appreciate the help, I'll keep trying to get some positive results. Did you use the default settings? Looks like you did.

OjN
05-03-2018, 07:40 AM
Do you have friction in the table plane?
You maybe need change the proprieties of you Billiard table and incease friction

jimiclaybrooks
05-03-2018, 08:30 AM
thanks, I'll try that.

jimiclaybrooks
05-03-2018, 11:14 AM
I have to say, I'm really frustrated with the bullet dynamics system here. First, the entire rack of balls (15 in a pyramid) wouldn't move hardly at all. So, I went for the simple, like I usually do. Just three balls, two balls and a cue. One or both balls go flying off the table!! Either the balls won't roll on the table or else they go off into space like projectiles! But a normal roll like a real pool ball, unobtainable. And I've played with all of the settings, which by the way, don't seem to be behaving consistently. This is very frustrating! Why, for instance, would the one ball just change course in the middle of a roll? Without touching anything, it just turns almost 90 degrees and heads in a different direction! WHAT?????

BeeVee
05-03-2018, 11:20 AM
Share your scene? Maybe we can better help then.

B

GraphXs
05-03-2018, 12:45 PM
Here is a 2015 sample version. attached

BeeVee
05-03-2018, 02:18 PM
Looking at the scene that GraphXs posted, I was wondering why all the balls were rolling off the edge, then checked the World Properties and saw that gravity was also 4m in the X! Changed the balls to sphere shapes as well and they are behaving quite nicely.

B

141533

BeeVee
05-03-2018, 02:45 PM
Slightly updated and even have some backspin on some of the balls, reckon you could animate the cue on the Bank to give it some spin too...

B



141534

jimiclaybrooks
05-03-2018, 06:46 PM
OK, here's the scene I'm working on. Its nine ball instead of a full rack, but at this point I'd settle for nine balls. I'm really interested to see if anyone can fix this. Thanks

jwiede
05-03-2018, 07:30 PM
Is there a reason you can't use similar settings to the ones provided in post #10 above?

Did you review how the scene posted in #10 was changed from the original to yield a working physics simulation?

jimiclaybrooks
05-04-2018, 08:35 AM
no, I didn't have time yesterday. doing that now, thanks. Well I did look at it, and I'm not seeing anything that will help me. First off, pool balls don't roll over one another, which has been a problem. Secondly, these balls don't look heavy enough. They move like they're not that heavy at all, so that's another problem. And thirdly, the balls don't react to one another realistically. i do appreciate the help and the efforts made, but this doesn't really show me what I need to see.

XswampyX
05-04-2018, 01:35 PM
Have a look.

141562

A couple of things I noticed about your original scene...

It's too small, bullet likes larger objects so mine is 10 times the size.

You created a nice looking table, but it isn't very bullet friendly. Use a hidden simpler mesh for your collision objects.

You have each ball set with it's own physics in bullet, every time you need to test a setting you have to change every ball.... what a ball ache! :D
Use a null for each setting and then assign it as an envelope.

You are going to have problems getting the balls to stop spinning/rolling this is just how bullet physics is. You will have to freeze each shot and start the simulation again.

Hope it helps.

jimiclaybrooks
05-04-2018, 04:44 PM
Thanks for the tips. It seems you didn' t notice, but there's a low poly collision obj that I used for the simulation, not the table. Its just for show. The balls were scaled at actual size, which is 2 inches. Didn't know that would be a problem. Great tip on the null, I'll try that, but realistically, I think I'll just get a camera and shoot a break on a real table. At this point, it would be a lot less hassle, and it would show what I really need, which is the reaction of the balls being hit by the cue. I was a high school champ in billiards, so I'm well aware of how the balls react on a breakup. Thanks again for the help.

XswampyX
05-05-2018, 06:10 AM
Thanks for the tips. It seems you didn' t notice, but there's a low poly collision obj that I used for the simulation, not the table. Its just for show. The balls were scaled at actual size, which is 2 inches. Didn't know that would be a problem. Great tip on the null, I'll try that, but realistically, I think I'll just get a camera and shoot a break on a real table. At this point, it would be a lot less hassle, and it would show what I really need, which is the reaction of the balls being hit by the cue. I was a high school champ in billiards, so I'm well aware of how the balls react on a breakup. Thanks again for the help.

I did notice.... and it's wrong. Objects in bullet need to be 3d and simple. I changed out your collision object for a better one. Also you can't have the bed of the table sharing the physical properties of the bumpers around the side as they are completely different. So I changed that over to a new layer.

The scene is posted above, why don't you actually look at it?

Strange.

jimiclaybrooks
05-05-2018, 05:59 PM
In my defense, my wife is very sick, so I'm distracted alot of the time. I don't have dedicated time like I used to, where I can just sit down and work. Also, I have a job that breaks up my day, so I'm out alot as well. That said, I just don't have time to work on these new features in LWave. I certainly didn't know or appreciate the issue with scale, and it would have taken me quite a long time to figure that one out, if I'd been on my own. So I owe you one for your help with this scene. It works alot better than I thought it would. Maybe this summer I'll have some time to really play around with my new toys, school will be out, and I'll be on break. And hopefully, wifey will be doing better as well. We'll see... thanks again for your help. Much appreciated.

XswampyX
05-05-2018, 06:31 PM
Oh... Hope it all goes well for you. In my defence... I can be an arse!

Good luck with it all.

SBowie
05-06-2018, 07:35 PM
In my defence... I can be an arse!that's a great line. I'm sure I'll be able to use it often, too, if you don't mind being plagiarized.