View Full Version : Help with particles collision self detection

06-10-2003, 05:30 AM
Im trying to animate particles to represent water filling up a cup, I selected the detect self collision, create a collision for the cup, but the particles just keep in the bottom of the cup, all of them, they donīt collide each other, only collide with the cup. I donīt know why, is it a bug? Iīm using version 7 for pc and only one hv emitther, thanks.

06-10-2003, 07:34 AM
Did you use FX_Start? This actually calculates particle interactions, the realtime preview doesn't.

06-10-2003, 08:44 AM
FX start...huh...I was trying to find out wast it was made for:eek:
Well, back to the manual...
I thought that the final render was the final calculation. It behaves like motion saving options, u have to play all the way the animation and then itīs ready, is it? I have to render to see the self collision, or fx_start calculate for preview too?

06-10-2003, 10:27 AM
For a start look at the demo scene included in LW:

This does exactly what you're trying to do.

Anything other than simple collision requires you press 'fxstart', which makes LW do full dynamics simulation for particle stuff. You can then save the motion and keep it for later use.

06-11-2003, 06:39 AM
Dodgy, I remembered I saw something like that one day, just didnīt remeber where:D
My cup experiment is almost there...Im playing with the particles size and props for a better looking animation...
Just for curiosity, I tryed to fill a long tube and it didnīt work fine...
I have to use a larger particle size to fill it up faster, but it causes the particles to look so artificial...Iīm testing on!!!

06-11-2003, 03:12 PM
you might be able to cheat and move the bottom of the tube upwards to make it seems as if the tube is filling faster. I really don't know if it would work but its a thought,


06-12-2003, 05:22 AM
Heheheh, thatīs a great idea, but if the tube is transparent...
iīm found another problem, it seems that my partycles are traspassing the tube :( I tryed to keep the particle size the same as the hypertexture but itīs still hapenning, the tube is a simple curve lathed...the collision is set on object....

06-12-2003, 07:54 AM
when you get this thing to work i would really llike to see it. i tried to show fluid moving through a pipe/filling it. i ended up putting it on the back burner out of frustration.

it would be nice to see what you come up with!

06-12-2003, 09:39 AM
Kthegene, so do I want hehehehe
The physical simulation is my goal here, since the"liquid" is not chosen yet. I had some succes with my cup scene with the chrome preset. Now, I want something that look/behaves like water for the tube test. Needs a lot of tweeking....

06-17-2003, 06:14 AM
Blast! I analysed "scenes/features/particlefx2/ fxcollisioncupswish.lws but I canīt figure out!
That scene is perfect, but I canīt get the same!

That scene is a recorded motion, the collision detection settings are-

detection none
selfdetection crowd
force 350 %
viscosity 10% (i think its viscosity)

Particle weight, everything is equal, fx-start, etc. I copied to my scene, but itīs not like the example...am I missing something? Could be my cup model? Any tip? Man, Iīll post some pics later...

About the particles transpassing the cup, itīs now ok (it needs some space for the particles to collide the object surface).