[Gmsh] Subdivide extruded surfaces?

[Rui Maciel]

I've defined  a volume by extruding a rectangular transfinite surface 
(example provided below) and now I'm looking for a way to control how 
that volume is refined.  Until now I was able to set the number of 
subdivisions in the extrusion's direction by specifying the number of 
layers, but I haven't found a way to refine surfaces or even how to 
subdivide individual line segments used to define a surface.

So, my questions are: is there a better way to set how a extruded volume 
is subdivided in the extrusion's direction?  And does Gmsh provide a way 
to subdivide surfaces or even individual lines used to define surfaces?  
If so, can anyone provide an example?


Thanks in advance,
Rui Maciel


x = 1.00;
y = 1.00;
h = 0.10;

div = 1;

Point(1) = {    -x/2,    -y/2, -h/2, 1e+22};
Point(2) = {     x/2,    -y/2, -h/2, 1e+22};
Point(3) = {     x/2,     y/2, -h/2, 1e+22};
Point(4) = {    -x/2,     y/2, -h/2, 1e+22};

Line(1) = {1, 2};
Line(2) = {2, 3};
Line(3) = {3, 4};
Line(4) = {4, 1};

Line Loop(6) = {1, 2, 3, 4};
Plane Surface(6) = {6};

Transfinite Line{1:4} = div;
Transfinite Surface{6} = {1, 2, 3, 4};

Recombine Surface{6};

Extrude {0, 0, h} {
   Surface{6}; Layers{ 2*div}; Recombine;
}