Wind Tunnel effect in POPS

[bandini]

Not exactly what I want, but as close as I can come to describing it. Basically, I want particles to flow around and cling to an object. I know about the creep sop - it's not exactly what I'm looking for. Particles should not start on the object's geo, and they should be free to leave it once they reach a certain lifespan or escape velocity or other condition of my choosing. I have heard mention of people using sdf volumes to create avoidance fields for the particles. I am interested in trying this. Just not sure how it is done. Anyone have a simple example hip they can share?

Thanks!

[pclaes]

The clinging to an object can be seen here (basically playing with the "STATE"):

http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&p=97495#97495

The SDF collisions are here:

Have a look at the "volume sample/gradient ..." vops. They will allow you to access the value of a voxel as well as the gradient. You can use the gradient vector (normalized or not) as your force.

Or perform a search on the forum for "volume gradient, sdf collisions, volume sample".

Have fun!

[bandini]

Thanks, Peter!

The clinging to an object can be seen here (basically playing with the "STATE"):

http://www.sidefx.co...c&p=97495#97495

The SDF collisions are here:

http://forums.odforc...dpost__p__62434

Have a look at the "volume sample/gradient ..." vops. They will allow you to access the value of a voxel as well as the gradient. You can use the gradient vector (normalized or not) as your force.

Or perform a search on the forum for "volume gradient, sdf collisions, volume sample".

Have fun!