# Chain of vectors (itinerary-like)?

hi there

I m pretty new to Paraview sorry, my need is basic but I couldnt find any answer so far accross discussions/examples etc.
My input data is a serie of points defined by their (x,y,z) coordinates respectively (csv, one line per point) and I need to print a vector from point A to point B, and a vector from point B to point C etc… similarly to an itinerary with steps on a map. I need to be able to print a trajectory made of 50M points minimum.

Can I achieve this with Paraview and how?
The closest I could get to trace a single vector is reproducing this : https://vtk.org/Wiki/VTK/Examples/Python/GeometricObjects/Display/OrientedArrow in a custom filter, but it seems a lot of computation to print a single vector ?..

thanks a lot!
Charlie

A simple programmable filter should do the trick. Juste create a polyline cells for your points.

Hi Mathieu!
I did using the following script (https://stackoverflow.com/questions/22438140/how-to-connect-points-in-paraview)
I am able to plot lines between point using the polyline, but not the arrow itself, I need to be able to show the direction of the itinerary (arrow starting from point and ending A to B, then another from B to C …) .
Is it doable using a polyline?

thanks
Charlie

Then this is completely different. You want to use a Glyph filter.

Thanks I will try, do you recommend to pre-compute the vectors (ie to be displayed between points) outside ParaView, or can I do it directly in ParaView (ie vector to be displayed at point A is computed using B(Xb,Yb,Zb) - A(Ax,Ya,Za) ? )
Thanks

You can compute the vectors using a programmable filter.

Hi Mathieu
I have managed to compute the vectors that are used to orientate the glyphs (ie towards next point). However I m now struggling with the 2D arrows that are always centered on the point they belong to.

• Is there a way to offset the 2Dvectors glyph along their orientation vector ? even with coding?
Thanks a lot
Charlie

this is what I got for now, not so great as per the position of glyphs…

Set CenterX to 0.5

Hi Mathieu, sorry but I could not find anywhere any reference or example on how/where to change “CenterX” - can you please elaborate? what does this variable/method refer to / how do I do that ? Thanks again !!

Charlie: Try by setting the X component of the `Translate` property in the `Glyph Transform` group.

Actually, setting the first component of the Center property to 0.5 should be better.
Mkae sure to show advanced options first by clicking on the cog wheel, top right.

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big Thanks Mathieu, thanks Joachim … I know have nice arrows! (I used Mathieu s way) please see below !

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Hi Mathieu,
just fyi I have opened a new topic because it seems it doesn’t scale on the Windows GUI client : Paraview Gui crashes on Windows 10 with large file
Charlie