Hi all,

Pumps! world of pain. Just trying to pump some flip about. The shelf tool either error, or if they don't the result is that the fluid (the particles you see inside the dop) just vanish on frame 2.

I'm using a flip tank rather than emitting from an object. I've set up a pump object in sops, with 2 voxel grids using rasterize attributes, a scalar one called pump set to 1 and a vector one called v set to 0,1,0. I use volume source in dops to import them, source field v, target field vel, and source field pump, target field pump.

Pretty please how do I set up a pump manually to work with a flip tank?


I should mention I can do it in Houdini 17.5 just not later versions, and a hip that works in 17.5 is broken in 19.5.

cheers,

A.

Ok...

good news/
so with a bit of judicious butchery of other peoples hip files I've managed to cobble something together that works.

bad news/
I've almost no idea what it's actually doing.

Here's my very patchy theory...

scalarfield1 just says here have a scalarfield called pump, it has no size or values yet.
sopsolver1 merges in the pump object again and does something with some data.
gasresizefield1 takes the pump field and makes it the size of the pump object.
the source node just puts values into the vel and pump fields.

One thing I don't get is how the sop solver is generating the "size" data. There's nothing I can see that links the size of the pump object to the data called size.

any info to help me out would be great,

cheers,

A.