Estrange behavior of particles previz in 2.56 anybody?

Hello everybody,

I´m having an issue when previz particles in latest official beta in my computer at home running Vista.

I set my particles and a collision object in a way that particles get stucked to this object. I then push play button and the previz seems to work fine. Problem arises if I let the previz reach the end of the timeline and start again or if I scrubb the timeline. The particles reach the collision object and start to bounce rythmically, all in phase. If I reload the file I got the same problem even if I close Blender and open it again. In fact when I reload, sometimes it gives me a first OK previz, sometimes particles rock the cashbah :RocknRoll: from the very beggining. I asumme that somehow previz has been stored in memory??

I first thought I was doing something wrong so, as soon as I arrived at work, I made this very simple scene with Blender 2.55 64 bits running on Win7 and no such weirderness. I saved the scene and brought it back home to test it. The problem strikes back.

********************************* EDIT *******************************************

Well, just in case you’re interested. I installed 2.56 at work and 2.55 at home. Both 2.56 installs show the same weird behaviour and both 2.55 installs seem to work allright (tho’ something strange tends to happen while scrubbing in the timeline).

So I don´t know if this can be called a bug but it’s really bugging me.


Sadly 2.56a didn’t solve the problem.

Try lowering your cache step. I had the same problem and this seemed to take care of it. It seem like at the default (10) some of the particles have a chance to wind up in an indeterminate position and therefore it goes “whoops too far past collision” and then move them back and then advances them again and repeats the process. At least that seems like the behavior, because my particles were definitely passing the collision bounds.