( remake of GLSL shader by Protarget )
: h sin 43758.5453 t 9 / 60 mod - * dup floor - ;
: b
2dup 2dup
311.7 127.1 z* h swap drop x - dup *
-rot
183.3 269.5 z* h swap drop y - dup *
+ sqrt
r> 2dup
<
dup 2dup >r >r >r >r swap
t x + cos *
t x + sin *
r> * swap r> not * +
-rot 2dup +
r> * >r> not r> * +
>r
rot >r
1 +
;
: a 1 + 0 b b b drop ;
0 >r 999 >r
-1 a a a drop
r> 400 * cos
r> h *
1.7 * dup dup