@Leaf:
Well you wanted some help with the IF statement, so I wrote it
Basicly it checks if the my entity was clipped in the last frame, which means that it is potentially invisible (if clipped = on), so I check if clipped is off or not on (!= on).
Then I check if the distance of the my entity to the camera is below or equal a certain value.
Just enter a value for "many_quants"

@xXxGuitar: No problem mate

EDIT:
An quick example Code:

---

action my_bounding_box_char
{
  wait(1);
  c_updatehull(my,my.frame);
  wait(2);
  
  while(me)
  {
    if(my.clipped != on && vec_dist(my.x,camera.x <= 500)
    {
      beep;
    }
    wait(1);
  }
}

---

That code should bring some noise into your level (due to the "beep;")