My trimmed down _real quick_ stab at it.
Looks a little off in the way that I expected.
Have to try an atan2 in there to see what happens.

.... and I'm off to work.

#version 3.7;

#include "math.inc"
#include "functions.inc"
#include "rad_def.inc"
#include "colors.inc"
#include "rand.inc"

#default {
    pigment { rgb <0.07,0.37,0.75> }
    finish { ambient 0 }
    }

global_settings {
     assumed_gamma 1.0
     // max_trace_level 10
     }

light_source { <60.0, 120.0, -50.0> rgb 1 }

camera {
    ultra_wide_angle
    location <0, 75, 0>/10
//    location <0.0, 15.0, -25.0>
    up y
    right x*(image_width/image_height)
    look_at <0.0, 6.0, 25.0>*0
    }

#declare Line = 0.1;

#declare START = <0, 0, 0>;
#for (T, 0, tau)

#declare END = <cos(T), 0, sin(T)>;

#local wall_vec = vnormalize (END - START);
#local wall_vec = <wall_vec.u, 0, wall_vec.v>;
#local wall_th  = degrees (acos (vdot (wall_vec, x)));

cylinder {<0,0,0>, x, Line rotate -wall_th*y translate x*3 translate END pigment
{Red}}

#end

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