// mesh densities
dense=0.01;
coarse=0.5;

// lattice parameters
a=1;
c=3;

// polygon order
h=6;


//bases
For i In {1:h}
Point (i) = {a*Cos(2*Pi/h*i),a*Sin(2*Pi/h*i),0,coarse};
Point (i+h) = {a*Cos(2*Pi/h*(i)),a*Sin(2*Pi/h*(i)),c,coarse};
Line (i) = {i,i+h};
EndFor


For i In {1:h-1}
Line (h+i)={i,i+1};
Line (2*h+i)={h+i,h+i+1};
EndFor
Line (2*h) = {h,1};
Line (3*h) = {2*h,h+1};


// fcc point
Point (2*h+1) = {0,0,c,dense}; 
For i In {1:h}
Line (3*h+i)={h+i,2*h+1};
EndFor



//faces
For i In {1:h-1}
Line Loop (i)={-i,i+1,h+i,-2*h-i};
Plane Surface (i) = {i};
Line Loop (h+i)={2*h+i,-3*h-i,3*h+i+1};
Plane Surface (h+i) = {h+i};
EndFor
Line Loop (h)={-h,1,2*h,-3*h};
Plane Surface (h) = {h};
Line Loop (2*h)={3*h,-4*h,3*h+1};
Plane Surface (2*h) = {2*h};

Line Loop (2*h+1)={h+1,h+2,h+3,h+4,h+5,h+6};
Plane Surface (2*h+1) = {2*h+1};


// volume
Surface Loop (1) = {1,2,3,4,5,6,7,8,9,10,11,12,13};
Volume (1) = {1};