cotmatrix and direction of mean curvature normal about gptoolbox

[alecjacobson]

mean curvature normal is the mean curvature H times the unit normal N, so if the mean curvature is negative then the mean curvature normal H*N will point in the opposite direction of N.

I'm surprised there aren't more red dots.

discrete mean curvature can also be zero H=0. E.g., in the case of a flat one-ring around a vertex.

If you normalize a near zero-length mean curvature normal vector to get a unit length vector, then you'll just see a seemingly random vector that's determined by floating point error.

[SuwoongHeo]

@alecjacobson Thank you for your answer sir. My original problem is computing mesh normal using a linear operator. So I thought Laplacian with cotangent weight is a good approximation for this problem.
I had computed the magnitude of mean curvature H from |L*V|. The minimum value of H was near 1e-09(The point I plotted above has H value of 1e-07). I think it is not in the range of floating point error.