Sim inside tube object

Hi, want to simulate inside the tube object, but no matter what I do there is no collisions.
Doesnt work with reversing normals, applying clotch or connect.


Post your scene file up, basic scene with your tfd and I will set it up for you

tfd inside.c4d (321.8 KB)
Uploaded scene file

Very odd. For a start the buoyancy seems to be reversed and I fixed that by deleting the container and creating a new one. But I cannot get the hollow cube to act as a tube. I tried creating a new elongated cube and extruded the ploys ( which you need to do anyway to get thickness for the collider) but still no joy. Perhaps Jascha could have a look and see what the issue is. Try emailing support.

indeed very odd, as it does not work in any hollow object. Where can I download other versions? maybe previous older would work

Yes testing again on an old tutorial setup it seems not to be working as it used to. Ask Jascha about older versions and a fix…if needed.

ok i have it working in an older file using the tfd v1462 but it does not work with your file. very odd i must be missing something !! I will post a file in a minute or two

Here I have it working scene file below. Tear it apart and see if you can replicate it. The scene is part of my tutorial set
My TFD Tutorials
fillproj.c4d (1.2 MB)

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Your collision object needs walls that are thicker than one voxel. As it is, it’s “wall” has zero thickness, since it’s only one layer of polygons. As a result, the simulation will treat it as a solid tube.
Below are your tube and a simple (somewhat resized) C4D Tube object side by side for comparison to illustrate the required “wall” thickness.

The simulation must resolve collision objects on a voxel grid. In order for the walls to show up, they must be thick enough to cover at least one voxel.
To check that the sim has resolved your collision object correctly, you can look at the Collision channel in the viewport. To do this,

  • check Container/Cache/Cache Collision
  • run the sim on one frame s.t. the collision object gets converted
  • In Viewport Preview
    • set Channel to Collision
    • set Shader to None
    • set Preview Mode to Single Slice
    • ensure Range Start is 0 and End is 1

Then you should get sth. like the image below.

Here the blue region is solid and the red region is free space where the fluid can move.


I tried extruding his object and as soon as the emitter was inside his object it failed.

How does the Collision channel of the extruded object look like?

Not sure as I am rendering ATM but his scene file is in the post above.