PRT Loader as velocity field

Since today, I can’t pick anymore a PRT loader (with a realflow’s bin sequence) as a velocity source. ( But I can pick it as a distribution)
I use the same bin sequence than yesterday, everything is the same…
And if I open the max file I saved yesterday, I can simulate with the PRT loader as a velocity source. But if I delete the PRT loader from the velocity source, I can’t pick it anymore.

That is strange, but it will be changed in Beta 4 anyway (we updated all picking filters).

The easiest way to hack this is to open the file StokeUI.ms in your Thinkbox\Stoke MX\Scripts\ folder and locate the line

rollout paramsVelocityFieldRollout "Velocity Field" (
The line right after it is the

fn filterSources obj = ...

Replace that line with

fn filterSources obj = (true)

This will technically remove all filtering and allow you to pick anything, even if it is not a valid source.
Save the file, restart Max and you should be able to pick any object.

In Beta 4, that function will use better methods to test for Max Force SpaceWarps, Stoke-supported particles, FumeFX and Ember objects. But for now the above hack should do…