particle up-rez.

[super gnu]

in houdini you can take a particle system (specifically grains in this case) and replace the original particle with a cloud of new particles randomly positioned around the original centrepoint. this is great for adding apparent detail in sand simulations etc..

however uprezzing 10x (the default) basically makes an alembic file 10x the size. which is logistically very painful.

is there any way to do things like this as a rendertime operation? an option in the pointparticle shader? i guess its too obscure and specific to expect a new feature in vray eh...

[joconnell]

It's stoke pretty much.

[vlado]

is there any way to do things like this as a rendertime operation? an option in the pointparticle shader? i guess its too obscure and specific to expect a new feature in vray eh...

This was requested before, and it's totally doable, but my worry is that users would need this process to be controllable and I have no idea what kind of control is needed...

Best regards,
Vlado

[super gnu]

hm well beyond my desire to avoid 800gb alembic files, im rather inexperienced in this field, so id not be the best to advise on what features may or may not be useful.

i guess the ideal in the end is to advect new particles based on the velocities of surrounding ones. that would give the most convincing "upres" but in my case a simple "replace each particle with 10 smaller ones" is, while not ideal, probably sufficient.. and to replicate the control present in the houdini setup, you just have a number to replace with, a scatter radius, and an option to control new particle size, the last two of which are linked by expression to the original particle radius.

-it could get a touch complicated when it came to choosing colours for the new particles. making them take only the parent colour isnt ideal. in my case im using random colours from a palette, so its easy (in houdini) just to apply the colouring after the duplication is done.

stoke can do this kinda stuff in max you say John? to an imported alembic? of 35 million particles? without falling over?

i really must take Bobo up on his offer of a trial.. i cant really carry on moaning about node based stuff being hard to pick up. if im setting the damn thing up in houdini.