Traditional Culture Encyclopedia - Photography major - The orthographic projection of a straight line on the plane is.

The orthographic projection of a straight line on the plane is.

Thinking analysis: Answer according to the different positional relationship between the straight line and the plane. When the straight line and the plane are perpendicular, the projection of the straight line in the plane is a point; When a straight line is parallel to a plane, the projection of the straight line in the plane is a straight line parallel to the straight line.

answer: a point or a straight line parallel to the straight line.