attaching 2 poly data

hey there.
where these two shapes are attached, I want to smooth the border of their intersection in a way that the sharp distinction between them fades or gets qualified, meaning the sharp distinction between two objects gets smoother, as if we fill the space so that the resulting U shape is more gradual compared to this.

I would truly appreciate your help with this.

@Charles_Gueunet

hey there. no ones could suggest me any idea or solution for this problem?

To be fair, ParaView isn’t really a mesh editing tool. Perhaps software like MeshLab or Blender may be useful.

I appreciate your suggestions, however I need to implement a solution based on the vespa deformation. I was wondering if anybody could give me any clues on how to acheive such performance through the vespa deformation.

Hello @sabaya

I have a solution to propose, but you will certainly have to update it to your needs.
Here is an example where I merged two triangulated surface with Vespa, and selected the “intersecting” area:

I have a cone with a scalar field set to value 1, and a cube with a scalar field set to 0, both triangulated.
Then, I use the Vespa boolean operation, with the interpolate attribute set to ON to get a single mesh from both. This mesh has points with the value 0 on the cube, and 1 on the cone.
In oder to select the interface, we use a trick here.
First, let’s subdivide our mesh, so we introduce new points with values between 0 and 1 around the interface.
Then, using the find data interface (cf 1 in the screenshot), select points with a scalar value between 0.1 and 0.9.
In order to include points from both the cone and the cube, I playes with the selection by extending it (+, cf 2 in the screenshot)
Finally, Freeze the selection and use the VESPA Region Fairing to smooth only this part.

Unfortunately, due to an issue with Eigen on my side I cannot show you this last part.

Thank you for the great suggestion, I will try to implement it and inform you of the result sir.

dear sir. I hava another question about “boolean”.
I am using the vtklinearextrusionfilter on my instances of data, after which I need to implement a boolean operation ( either through vtkbool or vespa), but I keep getting errors when using the result of vtklinearextrusionfilter in boolean operations. I was wondering there is any post processing method on the result of vtklinearextrusionfilter possible so that it can be further used in boolean operations without causing errors.

Hello @sabaya ,

Could you please provide more insights about what those errors are ?
The linear extrusion filter may disconnect every cells (you can check with a connectivity filter) which would result in a mesh non suitable for boolean operations. If this linear extrusion is mandatory, you need to build a watertight surface around your resulting mesh, the Alpha Wrapping in Vespa may helps you in this regard.

Best,

Hi there.
I tried two cases. First I tried to extrude one of my polydatas and then implement the boolean operation on one original data and the extruded data,
where I received these errors from VTKBool and vespa boolean.

VTKBool :
Capture

vespa boolean:


In the second case, using vtkclippolydata, I divided the polydata into two parts, and then extended them by scales of
10 and 20, respectively. Next, I decided to use the union operation instead of the vtkAppendPolyData, where I received these errors:

VTKBool:
Capture3

Vespa boolean:


they are attached by their sides though :frowning:

your proposed AlphaWrapping solution seems to work fine for the first case. thank youu.
but it takes too much time.