(Sorry for the delay in answering, we had a local Web-outage)
Hi Jerome Olivier,
The problem with deflectors are based on the speed the particles have. It is not a question of groups. Normally (!), but it is clear that the event happen, hence the red cubes are escaping not the pyramids. So, it is a question for the support. I can’t fix that. http://www.maxon.net/support/support-questions.html
Some typical notes: The deflector is not a constant observation during the frame, it takes a look at a particle and “decides” that it might not hit the deflector during that frame, so no bounce. The next frame checks for particles with the deflector and the particle too far away will be perhaps already behind the deflector. You might check with the support about this, as I think it is nothing that I can solve with an explanation, it seems to be a technical limitation.
My only answer is, introduce a second deflector, which might be tricky. This can be set behind the first deflector and bounce the escapers back int the game. Not that this will not work if the first deflector is set to bounce on both sides, this can create an endless trap.
The other way would be to slow them down when they come close to the deflector with a second deflector first, but set to event only. The energy loss during the bounce can be simulated in that way, e.g., slowing the particle down for the time being (event) and the second deflector bounces them with a little bit more (than before) back. I would even think that this comes closer to reality, as the bounce moment is certainly dependent on the material, on both sides (foam vs metal for example).
I have attached an example.
Again, you might request input from the support about this. Or just check my file, as one of my workarounds for this.
As a side note, normally the processing works nice without any concerns of the XGroup, but if something doesn’t work as expected, that would be my first place to check. First things on top, a logical process down then to the last “event”. (See image).
All the best
Sassi