[Gmsh] surface normals

[Jack Chessa]

I am sorry to bother you I am sure you are swamped with questions about
gmsh.  But I have on that I cannot figure out.  I am useign 1.46 on RH
and I cannot get the surface normals to flip.  I tried changing the sign
of the Physical Surface definition but this has no effect. Is this a bug
oor just my mstake.   Here are two example *.geo files which produce the
same surface normals (-z direction)

// file 1
L = 1;
h = L/3;
Point(1) = {0,0,0,h};
Point(2) = {L,0,0,h};
Point(3) = {L,L,0,h};
Point(4) = {0,L,0,h};
Line(1) = {1,2};
Line(2) = {2,3};
Line(3) = {3,4};
Line(4) = {4,1};
Line Loop(5) = {4,3,2,1};
Plane Surface(6) = {5};

Physical Surface(10) = {6};


and
// file 2
L = 1;
h = L/3;
Point(1) = {0,0,0,h};
Point(2) = {L,0,0,h};
Point(3) = {L,L,0,h};
Point(4) = {0,L,0,h};
Line(1) = {1,2};
Line(2) = {2,3};
Line(3) = {3,4};
Line(4) = {4,1};
Line Loop(5) = {4,3,2,1};
Plane Surface(6) = {5};

Physical Surface(10) = {-6};


Only the last line has changed! Any Ideas?

Thanks
Jack

Ps. Thanks for a very usefull program!

-- 
Jack Chessa
Department of Mechanical & Industrial Engineering
University of Texas at El Paso

Office: Engineering Building E101M
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