Particles : Hide particles before collision?

Beginners
1

Hi,

I’m trying to hide particles before colliging with a box. I was thinking to do that with “pstate” parameter and intance it with Chops in geometry but that doesn’t work.

Does someone already do that?

Thanks !

2

Just hide them or is it okay to kill the particles once they cross a given plane?

3

Here is an example :

test_particles.jpg
test_particles.jpg914×504 115 KB

I don’t know if this is the good way? And I don’t understand how this happen. But this is the result I want.

I can kill particles also but the idea is to see the particles after colliding with white box SOP and hidding them before. Do you have an idea about killing particles?
test_pyrogues.8.toe (7.86 KB)

4

This is a hard one.

Right now the closest I came up with was changing alpha based on a change in velocity.

I don’t know if this will work in your project, but it’s worth looking through this, and seeing if it will transfer to what you’re doing.

Cheers,
M
vChange.tox (2.83 KB)

5

Killing\Deleting points can be more expensive then hide them in this case.

Try groups and point attribute approach, you can hide\un hide points just by change custom attributes in them.

I use Matthew file and added red nodes.

hope it helps.

Barak.
point_attribute_disapear_example.toe (6.71 KB)

6

Thank you Matthew, barakooda.

I find a way to use both technics and having the result I want.

I also understand the first picture I got : My particles’ emitter was out from screen (top) so we don’t see it. But If you put it in the middle of the screen it will show some particles at the beginning.
When particles hit the collider they don’t really split herself, they generate new particles with new life! So we can use the “life(0)” value like alpha parameter to show or hide this new particles.

Don’t know if you’ll understand my explanation … :wink: