Seeing the moon split the warehouse into hard lines is a quick check of the layout. A sharp contrast means the light source is close, the shadows long, and anything moving will leave a distinct silhouette that can be traced. If the dark spots are uneven, it usually signals a potential blind spot or a hidden door that could hide a threat. Keep a mental map of those shadow edges—when they shift, so does the risk. If you hear a crack or a faint echo, cross-check it with the light pattern; it’s often the first clue that someone or something is moving. So yeah, light and dark aren’t just a poetic backdrop; they’re a low‑cost sensor that can tell you when the place is safe or not.