Directions of principal curvature

[Tom_V]

Before starting I should say that I am out of my depth both in respect of mathematical knowledge and use of CC, so I may need some basic concepts spelling out!

I have a nice point cloud of an irregular rock surface that features a clear convex ridge. I am interested in the possibility of “sheet fractures” forming in this rock. I would like to use an equation (see DOI: 10.1029/2011GL049354) that predicts whether the rock in question would experience the tensile stress to create such fractures. Two key terms in this equation relate to (1) the gaussian directions of principal curvature: k1 and k2; (2) the magnitude of curvature in those directions (1/radius). I would like to calculate (1) and (2) using Cloud Compare.

I have been playing with [Tools > Other > Compute Geometric Features] but I really don’t know what I am doing. Can anybody please suggest how I can obtain these values?

Thank you in advance!

Tom

Ridge for CC forum.JPG (136.49 KiB) Viewed 910 times

[daniel]

Well, sadly CC won't output the "directions" of curvature.

And it will only output their combined amplitude:
Gaussian curvature = k1 * k2
Mean curvature = k1 + k2