I am trying just to drop a 10-letter logo onto the floor and watch each letter bounce around alittle. It's 180 frames/ 30 FPS and around 60 and sometimes 90 frames it freezes and won't calculate the physics any more. Is anyone else having these problems with the physics engine? The lighting is one from the GI wizard. Thanks

I'd suggest rendering it without the GI and see if it still freezes. It's probably just getting too comlicated for your cpu with both turned on....

I tried using a 3 pt lighting (instead of GI) but the physics calculation slows down so much it is really almost stalled. It's a pretty simple animation - a ten letter logo with each individual letter dropping to the floor using a directional force, bouncing alittle and then coming to rest. My CPU isn't slow, it's a dell inspiron 8600, P 1.7, 1 G, 256 MB video ATI card. Any ideas or is it just limitations of the software?

I don't know, I think it might just be your computer. Not that your computer is really all that slow, but I just upgraded from a 1.4 ghz to a 2.8ghz pentium, and it is really a huge difference. For example, in poser 5, my old computer would lock up like yours is when trying to render a single frame of dynamic hair, and the new one will render that same frame in about 5 minutes. For something you could relate to, I made a physics animation recently of a few gemstones (about a dozen)dropping and bouncing. I rendered 5 seconds of it at 15 fps, at a resolution of 320x240, and it took about two hours. If I were going to do that same animation at 640x480, 30Fps, I'd leave it to render when I went to bed, and expect it to be done by morning. Add GI to that, and I'd have to leave it rendering friday night, and hope it'd be done monday morning! If I were to venture a guess, I'd say that the area where yours is locking up is right around when the letters start to collide with each other, and it suddenly has more interactions to calculate. Try leaving it rendering while you sleep, or go to work, or school, whichever, and see if it's still going when you get back. If you know that it takes, say, 2 hours to get to frame 90 where it slows to a crawl, and you leave it going for 8 hours while you work/sleep/school, and it's only on frame 101 when you get back, there's a problem.... Of course, I could be wrong....

Actually I think you may be right. When the letters collide and roll around alittle that's when the real slow down occurs. Thanks for the help

C3 will calculate physics for the first 24 frames or so and then render them. Then it will stop rendering and calculate the next set of frames before rendering them. Then C3 will appear to freeze because objects are really bouncing around by now and the CPU is very busy doing calculations until the objects settle down and it can start rendering each frame sooner again.

Message edited on: 10/02/2004 23:14

If you want to take some of the stress off your CPU "bake" the physics onto your text objects before you do any rendering. Run your animation to frame 180 in the Assembly room. All the calculations will be done. Change the motion for each object from physics to explicit. This will set up keys for all the motion and the down force can be deleted. CPU will just have to take care of the lighting/texturing at render time. Don't know if it will solve your problem but it should get to the freeze point alot faster. mdc

Dagnabit. Rendo ate my reply and I didn't even realize it. Yeah, run the physics FIRST and save the keyframes. A lot less hair-pulling that way if you have to tweak the materials and starting velocities and so forth. Once you got the physics nailed down, switch it off and render the animation.

If physics is still taking a real long time, do the simulation withlow-poly stand-ins. Then it's what, copy and paste the keyframes? I remember doing this but I don't remember how I did it... BTW: The first physics run I did for an actual image took six hours. That was on an ancient powermac, tho, and I was trying to generate the results of dropping an armful of fantastical weapons on a set of stone stairs. The next time I used it practically was on a g3 powerbook and it was fast enough to be a good alternative to hand-placing an ornate dagger on a table (using physics, I just allowed it to settle naturally to the table's surface. Then I rendered the still).

Message edited on: 10/03/2004 13:41

nomuse, I'm glad this place didn't eat this reply, too, because I learned something from it... albeit only remotely related to the original thread... I just spent hours trying to imagine how a complex object would settle onto a flat surface... didn't even think of using physics, because I really don't do that many animations (and those that I do are usually limited to the rotating logo variety). Thanks for the tip... I think I'll go set this up and see if I got anywhere close...

Thanks for the "baking" idea. It does make a big difference. Thanks again