LINES: vertical, horizontal, right & left questions

About 15 years ago, I vaguely recall reading that the first vertical lines of chinese characters progressed from the left to right, as suitable from the directions of the strokes inside the characters, but that either the way a scroll was held in the hand to write on or something in the printing process (i forget which) resulted in the current right-to-left vertical line. Would anyone know just how early that happened? In Wiki it says that in Korea today, they are sometimes mixing (from the)left-vertical writing with horizontal left to right columns in newspapers. I wonder if any Chinese or Japanese are trying this and whether any software supports it. Also, I wonder if Chinese, like Japanese made horizontal writing on the side of cars or trains go right-to-left on the right-side of the vehicle and left-to-right on the left so it would flow in the aerodynamically? correct direction, or not. I hope someone can answer these questions and others can ask and answer more.