Large number of dynamic objects
 

Hello. I'm been a Maya newbie for a little over a year now :p , and the thing that has always given me the most pain is dynamics. So I've been running some tests to try to work it out, and my main problem is that when I have a large number of dynamic objects they won't animate.

I made a large block of cubes by using "duplicate special" to duplicate one cube along the x axis a few times, then selecting that whole line of cubes and duplicating them along the z axis, then selecting all of the cubes and duplicating them along the y axis to create a block of maybe 50 or 100 cubes total.

Then I select them all, and go "create active rigid body", then I select them all again and apply a turbulence field or something to test them.

I hit the play button, but the problem is that it just plays through the entire sequence length with no animation at all. I know that a dynamics scene with 50 dynamic objects will take a long time to calculate and play, but it never says "Calculating...press escape to interrupt", and it never freezes up. It just plays the whole sequence with no dynamic animation at all.

Smaller numbers of cubes in a block, like 10 or 20, will sometimes animate, but never a larger number.

Any ideas or advice would be greatly appreciated. Thanks!

because you don't like square numbers other than 100?
i'm kidding

i made 100 cubes, selected them all, made them a rigid body and applied turbulance to them all, and it worked

i did as you said, cept i had them sitting above a soft body plane, although i don't think that made a difference
are you using the default turbulance? maybe you need to increase the force of your field

Hi Chirone. Thanks for replying!

I am using the default turbulence, but it always works on smaller numbers of cubes so I was assuming that turbulence wasn't the problem.

Have you tried making a solid block of cubes like I was talking about? I just tried making 100 duplicate cubes just using the "duplicate special" command and making them along the x axis so they are all in a straight line, and that animates fine with dynamics and turbulence.

The problem arises when I try to make a solid block of dynamic cubes that are aligned exactly with each other; so if I applied gravity to them they would remain stationary until disturbed by turbulence or a moving dynamic object.

Personally, my suspicion is that the problem is in the way I'm making the block; using special duplicate over and over again. Is there a better way to make a solid block?

Thanks!

are they all linked up in the dynamic relationship editor?

Rgh! I just tried creating the block a slightly different way and it worked. I hate it when this happens after I've already asked for help!

This time I made a line of cubes using special duplicate, then without deselecting or reselecting any of the cubes first (like I had done before) I just used special duplicate again on different axis until I had a block. I never even had to leave the special duplicate window.

But I do have a new problem. Turbulence does animate them when they are dynamic now, but I tried making a static dynamic cube and keyframing it moving through the block of active dynamic cubes, (trying to make a destructible block) and baking the animation (using default bake settings) but Maya crashed when the cube hit the block. I tried playing it without baking, but it took so long it seemed pointless if I couldn't bake it.

Is Maya usually unstable when dealing with calculation-heavy processes, or do I have a problem?

Thanks again!

Hello hammer.horror. Yeah I think they were. I still don't know why it didn't animate the other way, but I did find a work around. Thanks.

yeah i did create 100 blocks

maybe it's a hardware issue? how much RAM have you and what's your processor like?

when maya crashes can you see what the error was? (probably a whole bunch of garble but there might possibly be something useful there... but probably not)

I've got an Intel Core 2 Quad Q6600, with 4GB RAM.

The crash is always a full lockup with no error message. I just have to kill the program with the Windows Task Manager.

I'm thinking (hoping) that my install of Maya might be corrupt. It seems like it has been slower than it used to be. I reinstalled Maya not too long ago, but I brought over the My Documents folder unchanged from the last install.

Have you ever known the contents of the My Documents>maya folder to slow down or break an install for any reason?

Thanks!

i've never used the default directories when creating projects, so i can't really say
i've only seen the My Documents folder whenever i retrieve things sent to me via msn

i don't see anything wrong with your specs, i think its the same as mine... no wait, mine is Intel Core2 Quad Q9300

maybe you should post your scene if it's small enough?

Are you sure its crashed, if it freezes it could be just that maya is calculating it and taking ages to do it, though saying that it should do it. I would probably give, strangly, ncloth a go, if you have it.

There is also "dynamica" that you can get form a thread over on CGtalk, I think the thread is "Disney Dynamics System" thats pretty good, nice and fast and you can have lots and lots of objects in there.

As for slowing down, I managed to mess maya up, not sure what I did, but it wouldent script anything, had to delete the preferences and it solved it.

Well, it showed all the telltale signs of a crash, like the cursor being frozen as an hourglass when hovering over it. But I guess maybe it was my mistake.

Either way, thanks for the tip about the preferences. I'm going to try a reinstall of Maya, after saving my projects somewhere else and deleting the My Documents folder. Couldn't hurt.

And thanks a bunch for the Disney's Dynamica information! That sounds awesome.

Here are the links for anybody else who is curious:
http://forums.cgsociety.org/showthre...light=dynamica
http://www.bulletphysics.com/Bullet/wordpress/

I get the same issue as InverseTelecine. A small number of objects (about 40) and Maya Dynamics works fine. Any more and when I play the animation Maya hangs for about a minute then it plays and nothing moves.

Hello cgwhiz. I'm glad (or maybe not) to hear that somebody else has the problem as well.

Could you tell us what you were doing at the time? Maybe we can figure out some common traits.

I haven't had the time to reinstall Maya yet, so I don't know if that will help. But after I do, if I still have the problem, I'll post a scene to see if it does the same thing for anybody else.

Hi InverseTelecine,

I'm using Maya 2008 with SP1 - I just reinstalled last week so it's a clean install.

If I create a new scene, then a ball and then gravity I can play it and the ball falls as it should.

But, if I then create a cube, and 'duplicate special' it so I have about 100 cubes, when I play it Maya freezes for a few minutes and then plays the animation but nothing moves.

I do have an old PC - it's about 3 years old and only 1/2 Gig of RAM. I thought this was the problem.

Thanks for replying cgwhiz.

That sounds like it's exactly my problem too. I think (hope) we can rule out system requirements as the cause considering the difference between our two computers. I have a quad-core with 4GB RAM.

Besides, even if the system requirements were the problem it would still be a problem, since Maya should not do that when faced with a lot of dynamics and fewer system resources. It should just play through really slowly, not play through with no animation at all.

I've been short on time lately, so I can't make a demo scene where this error happens and post it right now, but I should have time soon. If you want to speed things along a little you could post one cgwhiz! :) But if you don't want to, no problem. I'll get to it sometime.