distorted mesh view - paraview 5.10.0

ParaView Support
1

Hello,
I’m visualizing a structured multi-block data set with paraview, but I have some problems in doing that.

distorted1
distorted11911×594 52.7 KB

The first image show the mesh associated with block number 1. The blocks are treated as time steps by paraview.
Then I add the mesh associated with the other block.

distorted2.png
distorted2.png1910×657 79.9 KB

The third image shows the same mesh as the second but with surface with edges representation.

distorted3
distorted31885×755 252 KB

Everything works until I deselect the first block from the extract block filter in order to visualize only the last block.

distorted4
distorted41907×738 231 KB

The mesh is completely distorted. Is a paraview bug?
Thank you

2

Is you dataset really small or really big in the 3D space ?

3

It is medium sized.
This is the mesh block I can’t see properly.

4

It does not appear distorded here

image
image1920×1148 315 KB

5

You have to zoom a lot as displayed in the previous images I uploaded.
This is how I see the mesh near the trailing edge…

distorted5
distorted51912×941 197 KB

Also a state file…edit the path to the vtk file…
distorted5.py (3.8 KB)

6

This is only a visual artifact, I’m not sure why it appears though.

@martink @timothee.chabat

7

I tried to visualize different meshes, each with a different number of points…
It appears only for a number of radial points greater than…let say at least 160… this is not a big number

8

It seems there is indeed a bug with how the display is made. My wild guess is that there is some floating point error happening when too much points lives in a too small geometrical space.

The selection does appear correctly though

image
image1056×752 110 KB

Sadly I don’t have any workaround in mind.

9

That is almost certainly a floating point issue. Tiny cells in a larger area. Try playing with the shiftscale setting in paraview for that representation.

10

Echo-ing Ken response, I just stumbled upon this in the release notes of ParaView (thanks Mathieu) :

“Focal Point Shift Scale” method (left) fixes rendering problems with floating-point precision compared to the “Auto Shift Scale” coordinate rescaling method (right).

Image : https://www.kitware.com/main/wp-content/uploads/2021/01/shift-scale-improvements.png

See section Faithful rendering of meshes with significantly different cell sizes of the ParaView 5.9 Release Notes.

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