particles colliding with the other objects

[gjaegy]

Hi,

I thought I would have found an answer in the forums, however, I haven't found any relevant similar topic...

Basically, I would like to have my particle systems to collide with the other objects (terrain, vehicles, etc..); mainly made of a custom-derived height field shape (terrain), and some convex decomposition shapes. I guess I will have something like 1000 particles per FX, and about 4 FXs at most. I am not interested in collision detection between particles themselves (will set the mask filters accordingly).

What would be the best approach to complete this ?

I guess the CL (miniCL, nVidia, etc..) doesn't fit here, as they don't take into account all the physic shapes, and are limited to a given restricted space (cube). Or maybe I am wrong ?

I might try to create a single sphere/box for each particle. However, I am affraid that the insertion/deletion of the rigid bodies (when particles are being created or when they have reached the end of their lifetime) might cause some performance issue... Pure speculation though.

Another idea, would be to simply consider particles as points (no volume), and use a simple ray tracing along their velocity vectors - I am pretty sure that would sufficient for my needs, even if some collisions might be missed).

Before I start implementing this approach, I would like to check whether anybody has already implemented this, and which solution would be the most appropriate here.

Any input ?

[codetiger]

Thanks for the good explanation. I too just posted the same topic few hours back and waiting for a response. I am willing to work with an existing project if already started or would like to start this. But just wanted to make sure whats the best way to do this.

My initial thought was:
1) Disable collision among particles.
2) Use a point Shape (no volume, no edges, and no rotations even, the shape is just represented by one vector)

[xexuxjy]

I would have thought that a sphereshape was your best choice to represent a particle, I guess you could come up with a custom point collision shape but I would have thought that it would have to have margins on it which would then pretty much make it a sphere anyway.
Disabling collisions between particles would be easy enough with collision masks, and you could tag certain surfaces as reacting to particles. I do think that you'll run into performance issues with any decent number of particles though.
Be interersting to see if anyone else has done something like this.