Projections of Points
The front view, top view and side view of point are denoted by various notations, which are given in the following table by considering point A.
| Actual Point | A |
| Front view | a' or AF |
| Top View | a or AH |
| Side View | a'' or AP |
Point Situated in I-Quadrant
When the point (say A) is situated in first quadrant as shown in (a). Its front view a’ is always above reference line x-y and top view a always below x-y. The distance between reference line x-y and front view a' is h which is equal to the distance between actual point A and HP. The distance between reference line x-y and top view a is w which is equal to that of actual point A and VP. Figure b shows orthographic view of point A.
Point Situated in II-Quadrant
When the point (say B) is situated in second quadrant as shown in Figure a. It’s both front view b’ and top view b are always above reference line x-y, as shown in b.The distance between reference line x-y and front view b’ is h which is equal to the distance between actual point B and HP. The distance between reference line x-y and top view b is w which is equal to that of actual point B and VP.Figure b shows orthographic view of point B.
Point Situated in III-Quadrant
When the point (say C) is situated in third quadrant as shown in Figure a. It’s front view c’ is always below x-y reference line and top view b is above x-y reference line as shown in Figure b.The distance between reference line x-y and front view c’ is h which is equal to the distance between actual point C and HP. The distance between reference line x-y and top view c is w which is equal to that of actual point C and VP.Figure b shows orthographic view of point C.
Point Situated in IV-Quadrant
When the point (say D) is situated in fourth quadrant as shown in Figure a. It’s both front view d’ and top view d are always below reference line x-y, as shown in Figure b.The distance between reference line x-y and front view d’ is h which is equal to the distance between actual point D and HP. The distance between reference line x-y and top view d is w which is equal to that of actual point D and VP.Figure b shows orthographic view of point D.
