Shading before copying (or keeping groups after copying)

[rurik]

Hello

I have a rain effect where I use motion blur. Since my particles are in front of a black background, the Motion Blur makes them hard to read. However when they hit the ground they are fairly visible.

I'm copying some metaballs to the particles, and have been playing with shading the final result. I realized boosting specularity makes the motion blurred raindrops much more visible, but then makes the colliding drops too bright.

I'm using a Copy SOP to add geo to my particles, but this makes me loose my groups. How would I go about shading the two groups separately? Do I have to create two Copy SOPS or is there another way?

Thanks

[yongbin]

It is wierd that copy sop doesn't have that funtionallity. Mightbe that option is exist, but we didn't find.

I tried this, but it seems no easy way.

My last approach is make attrib from group, and after copy regroup by this attrib. My approach isn't really that efficient I feel, but hope it help.

* if you have only two groups, make 2 copy will better.

copy_with_group.101.hipnc

[dobin]

hmm, why metaballs?

you can use render POP inside pop network or primitive SOP outside if you have particles already cached to set the render type as sphere, lines, tubes, etc.

[rurik]

Thanks Yongbin, that sounds like a great approach!

Dobin, Metaballs are useful in my case because I am making raindrops and the slight merging of the metaballs when they collide with each other is quite nice.

Thanks

[dobin]

ah, I see...

I would use vdb from particles in conjunction with vdb smooth, though