Fixing orientation of point clouds in webODM when images don't have GPS

For photogrammetry outputs from images that don’t have GPS, since ODM (of course) doesn’t know which way the pointcloud should be oriented, the output point cloud is often upside down or in some other incorrect orientation. In theory you can zoom roate the pointcloud in potree and set the camera view (under “scene”), but there seems to be an issue in potree where you can’t fully rotate the point cloud in all orientations so it isn’t possible to actually reorient the point cloud correctly.
I think this is a potree issue, but I thought I’d check here to see if anyhone has figured out a work-around.

Also, this might be a bit of an ODM issue as well because ODM seems to consistently make pointclouds that are upside-down if the image don’t have GPS. This is consistent enough that it makes me wonder if there might be a hacky fix that one could implement in ODM to address this.

Here’s an example of a point cloud that is upside down:
In this case the grey is supposed to be floor, but you can see that there isn’t anyway to rotate the model enough to get it in the correct orientation…
https://bit.ly/point-cloud-orientation-ex01

And another one (also upside down, hence me wondering why this seems consistently the opposite of the correct orientation)
https://bit.ly/point-cloud-orientation-ex02

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Mmm… Have you tried the “ground” camera control method? It let’s me orient my data however, and doesn’t slow down when you get close.

CloudCompare has a simple way of rotating a cloud to a “ground level”, you just select three points.

It’s a button with a triangle at the left side.

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yeah I’ve tried that, but all the datasets seem to only be able to do like one rotation and then they get stuck and can’t turn further. It would probably be ok if potree had a setting that provided the standard x,y,z rotation wheels (I imagine there’s a technical name for this) like they have on sketchfab for fixing model orientation, but since it doesn’t have something like that, it can be quite hard to rotate model in a reproducible way.

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It’s the problem I mentioned here:

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