line of direction, principal的用法和樣例：
例句
- All points along any line perpendicular to the orientation line are the same color.
與方向線(xiàn)垂直的任何一條線(xiàn)上的所有點(diǎn)為同一顏色。 - The angle of the orientation line determines which corners the starting and ending lines pass through.
方向線(xiàn)的角度決定起始線(xiàn)和結束線(xiàn)經(jīng)過(guò)的角。
