Render (HRB) particle with transparent object

[mtmorrione]

I am using the Hardware Render Buffer (HRB) to render a scene with a transparent torus and MultiStreak particles shooting through the hole. If the torus is opaque the particles render correctly with geometry mask turned on. If the torus is transparent the particles do not render correctly (behind / infornt) as they go through the hole. I read that z depth could be used to solve this problem. I can't find a good explaination of how to do this.

Can anyone explain the z depth method or some other technique?

Thanks,

Mike

[DjVoyager]

Are you colliding the particles with the torus? Does the torus has a transparency material on?

[mtmorrione]

Are you colliding the particles with the torus? Does the torus has a transparency material on?

No I am not colliding the particles with the torus, they are simply passing through the hole. The torus has a blin material and that I have made transparent.

Thanks for any help.

Mike

[stealth kid]

as far as i know, you cannot get z-depth information from hardware rendered particles unless you instance geometry to them. but try this: split your torus into 2 pieces, one should be behind the particles and one should be in front of them, relative to the camera. render all of this things separately, so that you will have 3 layes, and then compose them. i have not tryed this method, but maybe it will work. and make sure you have a good alpha channel for the torus pieces so that the seams will not show in the final image. i hope this helps you.