tolerance = 0.1;
height = 266 + tolerance;
rail_depth = 27.4 + tolerance;
extra_depth = 75 + tolerance;

rotate_vector_cos = 0.94; // 'x' of 20 degree rotation
rotate_vector_sin = 0.34; // 'y' of rotation

left_edge = -rotate_vector_sin * rail_depth;
right_edge = height * rotate_vector_cos;



points = [
  [left_edge, rotate_vector_cos * rail_depth], // top left
  [left_edge, 0], // drop to axis
  [left_edge, -extra_depth], // top to bottom of box
  [right_edge, -extra_depth], // bottom right
  [right_edge, rotate_vector_sin * height], // top right

  [left_edge + height * rotate_vector_cos, 
     rotate_vector_sin * height + rotate_vector_sin * rail_depth] // top point?
];



polygon(points = points);



