[Gmsh] Gmsh -- mean plane definition

[Romain Quey]

Hello,

I am wondering about one step of the 2-D mesh process within Gmsh.

Actually, I would like to know how the "mean plane" is defined in the
case where all the points of a 'plane surface' are not really in a
same plane.
In the source code, I found that the resulting plane is defined
according to a least squares criterion; but which form of the criterion
is it about? In other words, which expression is minimized?

I am using this option to approximate (slightly) non-planar faces by
planar ones...

I thank you in advance for your answer (in fact, it is for a 
presentation next week),... and thank you for Gmsh too!

Yours sincerely,

-- 
Romain QUEY, PhD student
Ecole des Mines de Saint-Etienne
Centre SMS / Dpt MMF (UMR 5146)
158 cours Fauriel
42023 Saint-Etienne, cedex 2
Tel. 04.77.49.97.38 - Fax. 04.77.42.66.78
E-mail : quey at emse.fr