Passing by. Xiayi to Yemiao passes through Matou, along the highway from Matou Town to Yemiao Township in Xiayi County from west to east to Wang Lou, Huang San Village, Yemiao Township. Spatial position of road centerline. In a narrow sense, it refers to the spatial position passing through the center line of the road longitudinally; In a broad sense, it refers to the position of a three-dimensional strip entity with a certain width, including the center line of the road.