Hi there I was following some of the Entagma tutorials on SOP solvers and I came across a minor problem shown above. How do I get the SOP solver to function on the first frame? Currently it is saying that Vdbadvect1 requires a vector although the VDBanalysis is plugged in and set to Gradient, it seems to work every now and then when I disconnect it and hook it up. After multiple attempts and adding a switch node to Input one with condition $F==1 and switching to the previous frame it still doesn't work..

Thanks!

The problem is that the node with the display flag in your solver was converting your VDB to polygons, and that result is being fed into the next iteration of your loop. The VDB operators in the next loop see polygon geometry, shout “WTF?”, and your loop breaks.

Attaching a fix. Just convert to polygons outside the solver.