View Full Version : How to fill object with falling sphere's, and then remove the object

11 November 2010, 02:48 PM
Hello all, a couple of weeks ago i posted a thread about my scene because i couldnt get it to work. PsychoSilence gave me some tips, tweaked my setup a bit, but it's still not working like it's supposed to (now when i open his tweaked file it's not working at all anymore).

Maybe my setup is way to overcomplicated, so what do you guys suggest on how to build a scene like this:
A logo, consisting of two letters, the M and the W. I want two emitters above the letters to emit particles (spheres) that fall into the letters (which are invisable) to form the logo. On a given frame i want to disable the deflector, and let the spheres fall onto the groundplane.

The way i build my scene:
I made my logo editable polly, removed the top face of the M and the three top faces of the W, add a shell modifier, and a Physx Collision Shape. I have a couple of invisable tubes (with Physx Collision Shape) to guide the sphere's into the open letters. This setup works, the letters fill up with sphere's.
But how to 'disable' the Physx Collision Shape. I know you can't just disable it, but isnt there a workaround??? I tried to chop my letters into a front and backside, which i animated out of the scene between two frames time (Animated Geometry enabled). This doesnt work, the spheres keep in place. PsychoSilence add a melt modifier to the letters, but this smashed the sphere's to the ground instead of falling do to gravity.

I hope you guys have some advice, because i've watched a lot of tutorials, but didnt find anything usefull for my problem.

11 November 2010, 05:46 PM
For something like this I would use a second flow with an Initial State Birth op.

Simply setup your first system and on the frame before you want the particle collisions with the Collision Shape object to cease, make that as your Initial State frame, in the 2nd system calculate the initial state, set its emit time to the initial state frame.

Back in the first system, add an Age Test, set it to absolute, set it on or one frame after your initial state frame, and a new event with a delete operator to kill the first system particles.

Posted an example: max2010

11 November 2010, 10:58 PM
Wow, thank you so much, it worked like a charm!!! Max still crashes every 6 changes I make to my scene, but that's another problem all together:)

Thanks for the help, now it's time for some finetuning! I'll post a link to my final result when it's done.

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11 November 2010, 10:58 PM
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