// I-9.fe
// Schoen's surface p. I, number 9

parameter height = .5 

// Programmer: Ken Brakke, brakke@susqu.edu, http://www.susqu.edu

/* Commands:
   gogo - typical evolution
   layers - 4 x 4 grid of two layers
   transforms off - show just single fundamental region
   setcolor - to color one side yellow, as in my web page.

   To turn off showing all the edges in the graphics display,
      hit the "e" key in the graphics window.
*/


// Transforms
view_transform_generators 3
1 0 0 2  0 1 0 0  0 0 1 0   0 0 0 1 // x translation
1 0 0 0  0 1 0 2  0 0 1 0   0 0 0 1 // y translation
swap_colors 0 1 0 0   1 0 0 0  0 0 1 height   0 0 0 1 // half-turn, up z-axis

vertices
1   0 0 0 fixed
2   1 0 0 fixed
3   1 1 0 fixed
4   0 1 0 fixed
5  -1 1 0 fixed
6  -1 0 0 fixed
7  -1 -1 0 fixed
8   0 -1 0 fixed
9   1 -1 0 fixed
10   0 0 height fixed
11   1 0 height fixed
12   1 1 height fixed
13   0 1 height fixed
14  -1 1 height fixed
15  -1 0 height fixed
16  -1 -1 height fixed
17   0 -1 height fixed
18   1 -1 height fixed

edges
1  1 2 fixed
2  2 3 fixed
3  3 1 fixed
4  1 4 fixed
5  4 5 fixed
6  5 1 fixed
7  1 6 fixed
8  6 7 fixed
9  7 1 fixed
10  1 8 fixed
11  8 9 fixed
12  9 1 fixed
13  10 11 fixed
14  11 12 fixed
15  12 10 fixed
16  10 13 fixed
17  13 14 fixed
18  14 10 fixed
19  10 15 fixed
20  15 16 fixed
21  16 10 fixed
22  10 17 fixed
23  17 18 fixed
24  18 10 fixed
25  1 10
26  1 10
27  1 10
28  1 10
29  2 11
30  3 12
31  4 13
32  5 14
33  6 15
34  7 16
35  8 17
36  9 18

faces
1   1 29 -13 -28
2   2 30 -14 -29
3   3 25 -15 -30
4   4 31 -16 -25
5   5 32 -17 -31
6   6 26 -18 -32
7   7 33 -19 -26
8   8  34 -20 -33
9   9 27 -21 -34
10  10 35 -22 -27
11  11 36 -23 -35
12  12 28 -24 -36

read
hessian_normal

// typical evolution
gogo := { l .8; r; g 5; u; g 5; u; g 5; r; g 5; u ; g 12;
          r; u; V; g 20;
          hessian; hessian; V; V; hessian; hessian;
    }

// 4x4 grid of two layers
layers := { transform_expr "abc"; show_trans "R"; }

// Set inside color to yellow
setcolor := { set facet backcolor yellow }

/* Commands:
   gogo - typical evolution
   layers - 4 x 4 grid of two layers
   transforms off - show just single fundamental region
   setcolor - to color one side yellow, as in my web page.

   To turn off showing all the edges in the graphics display,
      hit the "e" key in the graphics window.
*/