Tools>Fit>Plane and RANSAC

[ripo]

Is there a method in cloudcompare how the RANSAC algorithm accurately approximates the plan? I want to know the error that the algorithm RANSAC commits and the relative goodness of approximation between the plane and the point cloud.

[daniel]

The qRansacSD algorithm creates on output all the detected planes alongside with the points that were used to fit the plane (the points generally comes first and underneath you'll find the plane entity). So you can select both entities and compute the distances to get the RMS (use the 'Cloud to mesh distances' computation tool).

[Nicola]

Hello everyone!
I'm a geologist who's writing a paper about rock planar discontinuities recognition by the means of photogrammetric survey and cloudcompare tools like the Plane fitting (Fit>Plane). So i was wondering where can i find the bibliographic references about the algorithm used by this tool.
Though this is my first post on the forum i'm following Cloudcompare project from a lot of time and i would like to thank Daniel for his work!!!
waiting for answers, many thanks

[daniel]

Well, it will be hard to point a particular article for this. We are simply doing a least squares best fit of set of points by a 3D plane. In effect it's a simple application of Principal Component Analysis (https://en.wikipedia.org/wiki/Principal ... t_analysis).

Hence, Pearson's article (cited on the wikipedia page) should be the best source:

Pearson, K. (1901). "On Lines and Planes of Closest Fit to Systems of Points in Space" (PDF). Philosophical Magazine. 2 (11): 559–572. doi:10.1080/14786440109462720.

[Nicola]

thank you! this is what i was searching for :D!