BVTKNodes gallery

I’m starting this thread in a hope to form a gallery for scientific visualization renderings which utilize BVTKNodes add-on (original repository by Silvano Imboden, and my fork repository). BVTKNodes is a Blender add-on which allows creation and execution of VTK pipelines in Blender Node Editor. I hope that people will post and tell here how they have used BVTKNodes. Both renders and node tree images are welcome, since examples are the best way to learn. Feel free to post and also discuss! Are you using Blender and VTK?

Here is head data show case example:

7 Likes

Kitchen flow example, stream tracer + tube filter, coloring by integration time.

4 Likes

Just added fin example to my fork. Domain outline with tubes, plane slice with density data, and arrows from momentum vectors. Tried two different lightings.

2 Likes

Ok, this one is more art than scientific visualization, but the stream tracer ribbons in pictures do originate from CFD simulation. This is the OpenFOAM motorbike tutorial case (laminar SIMPLE solution), including the motor bike model (triangulated model --> reflections artefacts). The only thing I did was add smooth shading to faces, otherwise model is original.

This is a bit of a breakthrough for me, to get OpenFOAM data via BVTKNodes directly into Blender. Attached also image of node tree. Warning: Reading OpenFOAM cases with BVTKNodes like this has many many limitations. It took me quite some time to make this work.

3 Likes

Here is a visualization test of the computational hex-dominant volume mesh (created with SnappyHexMesh) for the same motorBike tutorial case, using latest add-on version. Color ramp (blue-to-red) goes from 3 to 6 refinement levels. 21 million verts in final Blender mesh, almost too large for my machine to render :slight_smile:.

1 Like

Here is example of two overpressure isosurfaces (using two vtkContourFilter nodes) around a flying object. Smooth shading, no extra mesh manipulation.

Nice to see that this is actively developed.

Hi,
this looks promising. A way to bypass Paraview in order to get CFD data into Blender.
Currently trying to get it to run on Windows.

Thomas

And … giving up for now.
I get as far as getting VTK compiled against the python. But Blender does not recognize the installed VTK.

Thomas

Hi @pmn77,

Following discussion in How to install Python packages with "pip" (Blender 2.8) I tested in Windows that you can install VTK into Blender’s python like this:

run CMD.EXE as administrator
cd C:\Program Files\Blender Foundation\Blender\2.80\python\bin
python.exe -m ensurepip
python.exe -m pip install vtk

After that you can “import vtk” in Blender’s Python Console. Edit: Currently it seems to install VTK 8.1.2 so I downgraded the add-on to use VTK 8.1.2 (was previously 8.2.0), because of the easy pip installation.

There was a bug in BVTKNodes logfile path for Windows which I fixed, so you should install the updated add-on from github. Thanks for the bug report!

PS. You can report bugs in github using the Issues tab.

BR,
Tuomo

Thanks a lot for your work :slight_smile: Any chance you can share the Blender files for these pictures? Would be very greatful (I am using CFD and currently learning Blender - your HQ content is awesome!). Also have you been successful to create transient renderings inside of Blender?

Hi, thanks for feedback!

I’ve been thinking about creating a “Blender How-To for OpenFOAM users” to OpenFOAM wiki Blender page or somewhere over there, but have not yet done this. Maybe one day…

Meanwhile, to learn Blender I suggest you go through tutorials in Youtube and Blender Cloud. To learn about BVTKNodes, the best material now is the Blender Conference 2018 BVTKNodes presentation by Silvano and Lorenzo. After that you can try out some of the node setups shown in this thread. Beware: It is not as easy as Paraview. Also, I am still learning how to use VTK…

Edit: I have not animated transient data with BVTKNodes. There is currently bug in Blender 2.8 which makes it necessary to use cumbersome workarounds for changing time steps.

BR,
Tuomo

1 Like

Would really love to see that Tuomo and happy to learn from you :slight_smile:

Thanks a lot for your links. Please let me know once you decided to open a new thread or step-by-step instruction on Github or any other platform, would be happy to help you and supply you with some CFD simulations if necessary.