Add particles at rendertime

[Mikael]

Hi!

I wonder how to add particles at rendertime that follows/based on a previous rendered bgeo-sequence of particles?

I guess it is pretty much what krakatoa do.

I read these threads and found it very interesting, but sadly there is currently no clusterThis for H12.5

http://forums.odforce.net/index.php?/topic/9633-generate-millions-particles-at-rendertime/

http://forums.odforce.net/index.php?/topic/7916-mantra-clusterthis-procedural-geometry-dso/

I also read this thread where they use delayed load shader, but as I understand they never add particles after the delayed load.

http://forums.odforce.net/index.php?/topic/10065-krakatoa-shader/

Most of these threads and posts are some years old, so how do people solve this now?

And I'm not awesome at programming so solutions without to much programming would be nice.

Thanks,

Mike

[DanBode]

in 12.5 they added a geometry shader called "point replicate porcedural"

it duplicates all your points n times and lets you use a cvex shader to position them.

I haven't gotten a chance to try it yet, but this should do what you need.

[Mikael]

that works nice! thanks! I also found the point replicate SOP, anyone have any thought on were it is best to crank up the particles? If I crank up with the SOP I would get bigger ifd and more network traffic(since I send to renderfarm), but if I use the procedural do I get increased rendertime?

[ikarus]

If you can generate it at render time it's less of a memory load on the machine, which probably the better choice.

[Mikael]

the point replicate procedural feel pretty slow to me. if I crank up my particles using the SOP I have a render time of approx 3 min (but a huge ifd file) and when I use the SHOP I get a render time close to 1 hour (but a pretty small ifd file). Am I doing anything wrong? or is there any checkbox or something I've missed?

[Naeem]

You could reduce the size of your IFDs by writing out your points to disk after the point replicate SOP and then using Delayed Load Procedural at render time.