4DFlow Pathline Streamline

mwestphal · October 30, 2023, 9:14am

There is only the velocity field on your data, the is no flow field.

mar.premi · October 30, 2023, 9:18am

But I can see the flow

mwestphal · October 30, 2023, 9:28am

These are glyphs representing the flow, but the flow data itself is missing from the Volume data you shared.

mar.premi · October 30, 2023, 9:32am

Ok I understand… Because I use a program call Mass (that merge the flow with the contours) for extract the vtk data.
I can only export these things.

mwestphal · October 30, 2023, 9:36am

I’m afraid that is a question for Mass, not ParaView.

woodscn · November 2, 2023, 10:21pm

The ParticlePath filter computes pathlines.

For the benefit of anyone interested, streamlines are computed by integrating along a vector field. Pathlines show the path a particle would follow if it were placed in that same vector field. For steady-state vector fields, there is no difference. For time-varying vector fields, this means that you advance the vector field in time as you’re moving the particle along.

mar.premi · November 17, 2023, 10:19am

Hi, I need help again.
In the software before I made an interpolation and so I have a pretty ugly contours
I found the filter smooth to adjust the contour but there is some way to smooth also the flow out of the contours? Because if I use Smooth filter also for the 4dflow it smooth also the inside and I don’t want that.
I saw the possibility to use extract selection but I don’t understand how to use it!

Do you have any suggestions?

mwestphal · November 17, 2023, 10:20am

please share a screenshot

mar.premi · November 17, 2023, 10:23am

Before the smooth of the contours:

After the smooth of the contour:

Can I remove the arrows of the velocity field out of the contour?

mwestphal · November 17, 2023, 10:25am

Hide the glyph filter ?

mar.premi · November 17, 2023, 10:26am

I don’t understand.
I want to “cut” the velocity field with the contour to obtain the velocity field only inside of the contour and then export them

mwestphal · November 17, 2023, 10:30am

You can use the Polydatadistance trick for this I think.

mar.premi · November 17, 2023, 10:52am

I create the filters but then this happen

mwestphal · November 17, 2023, 10:58am

The programmable filter should have your velocity field has an input.

mar.premi · November 17, 2023, 11:04am

Both clipper and slicer?
import paraview.modules.vtkPVVTKExtensionsFiltersGeneral as ext

inpMain = self.GetInputDataObject( 0, 0 )
inp = self.GetInputDataObject( 0, 1 )
out = self.GetOutput()

clipper = ext.vtkPVMetaClipDataSet()
clipper.SetInputDataObject(1998753LV_3dflow_vec_ph001.vtk*)
clipper.SetInsideOut(True)
function = vtk.vtkImplicitPolyDataDistance()
function.SetInput(1998753LV_3dflow_vec_ph001*)
clipper.SetDataSetClipFunction(function)
clipper.Update()

outData = clipper.GetOutputDataObject(0)
out.DeepCopy(outData)

and same for the other?

mwestphal · November 17, 2023, 11:07am

Absolutely not. Please follow the steps in the link I shared closely.

mar.premi · November 17, 2023, 11:15am

nothing happen

I’m appying them correctly?
The volume is my velocity fiels and the surface is the contour?

mwestphal · November 17, 2023, 1:49pm

please share your data

mar.premi · November 17, 2023, 2:00pm

woodscn · November 17, 2023, 4:06pm

It looks to me like the velocity field glyphs protrude out of the contour even before the smoothing. I’m not sure you’ll be able to get the result you want without cutting a bunch of the arrows in half, and I’m not sure if that’s what @mwestphal is suggesting.

The nature of arrow glyphs like that is that they protrude out of the velocity field pretty easily. Perhaps a stream tracer filter will do what you want?