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Author Topic: Inverted normals laserdata  (Read 1976 times)

Bastiaan Veenstra

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Inverted normals laserdata
« on: July 19, 2020, 04:09:23 PM »
Hi everyone,

Currently we are experiencing problems with importing laserdata into Metashape 1.6.3.10732 (and 1.6.2).
As shown in the attached image, some normals are inverted. Of course we are able to invert normals, but when selecting the entire pointcloud and using that function, it inverts normals based on the view from the camera, so the normals on the other side, which are facing correctly, are also inverted because of the view from the camera.

Is there any way to fix this without selecting every surface individually and inverted the wrong normals?

With best regards,

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Bastiaan Veenstra - 3D designer
« Last Edit: July 19, 2020, 05:19:47 PM by Bastiaan Veenstra »

James

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Re: Inverted normals laserdata
« Reply #1 on: September 02, 2020, 02:14:34 PM »
Just in case you are using Cyclone to export your laser data, the latest version (2020) allows you to export normals, whereas previously it seems it wasn't doing that properly/at all.

I have only tried it with the e57 format, but was having the same problem as you show until i upgraded my version of cyclone.

It does seem like metashape should be able to do a better job of estimating normals though, as quite often it estimates them pointing away from the scanner position, which i think should be included in e57 and ptx file types, for it to check against.

Even if you do get your normals all pointing the right way, the filter dense cloud function seems to scramble them all again, so do any decimation before you import if possible!