Fit plane dip angle and dip direction

[Graham]

Hi,

I am fitting planes to points on geological structures to obtain their orientation (dip angle and dip direction). When I save the planes as a .dxf and do a direct measurement of the plane in CAD, the dip angle and dip direction do not match what is reported in the CC Object name; both are off by a few degrees.

However, if I fit a plane to the original plane (fitted to the points), the orientation is the same as the .dxf version.

Any thoughts on this discrepancy?

Thanks in advance.

[daniel]

Which version of CC are you using? I know the way the dip and dip direction are computed changed a while ago (but it was mainly a matter of quadrants and signs, therefore the difference should be huge and not of a few degrees).

How do you fit a plane to the original plane? I guess it's with the CAD software? I hope both planes are then at the same position?

[Graham]

I'm using version 2.7.

By fitting a plane to the original plane, I mean re-doing the fit > plane in CC on the plane originally created by using the point cloud. This orientation matches the .dxf version I can measure in CAD, but does not match the orientation in the object name. Yes both planes are at the same position.

[daniel]

Hum, I couldn't reproduce the issue with the 2.8 beta version (and I don't remember any change that could explain this).

Can you test on your side with the 2.8 beta? And if you still observe this difference, can you send me your cloud maybe? (cloudcompare [at] danielgm.net).