Artifacts with multiple collider objects

Workflow
#1

Hi,
I’m no TFD expert so maybe this is an obvious one but…… I want to make a smoke sim creating mist over water on a lakeshore with TFD v1-0_1465.
Mist is emitted from a subdivided plane just above water level on which I have removed some polygons so smoke is not created “inside” the terrain, only above water. It has a noise volume emission texture.
I have 4 colliding objects :
-3 cylinders (submerged wood poles)
-a low-poly proxy of the terrain using baked polygon reduction.

Collision with the cylinders only does work as expected, but using the terrain as a collider gets me weird artifacts.
Strangely enough, those artifacts seem to be “aligned” with the vertical poles.

On the 1st frame of the sim (frame 0) it looks correct but from frame 1 on it shows this weird artifact here’s a top view showing vertical streaks in the sim on various frames

Any idea how I can fix this ?

TFD-artifacts
TFD-artifacts2604×868 370 KB

#2

Try checking on “smooth object collision” also see if giving the colliders some “bulk” helps ( extrusion). You can also try increasing the sub-steps and the resolution. But the smooth object collision it may do the trick.
My tutorial Set … TurbulenceFD (TFD) For Cinema 4D Fundamentals | Software | Training

#3

Hi Paul and thank you for your input.

-I first thought this would be because the terrain had no thickness so I tried extruding the faces inwards, didn’t change anything.
-I tried checking “smooth object collision” : didn’t fix it either.
-I wondered about sub-steps but I didn’t feel like the smoke was miving fast enough for this to be the reason missing on the collisions so… I finally posted my message here.

Your answer convinced me this must have something to do with the terrain thickness so I slept over it and gave it a new try with a fresh mind. This time I gave the terrain a “cleaner” thickness by using a cloth-surface and…. now it does work as expected :slight_smile:

Now that I can finally run my sim I ran into another weird thing, but that’s gonna be for a new thread, see you there maybe ?

1 Like
#4

Glad you got that sorted…now to get a surgeon to put your hair back.