Pictorial Views
A view of an object (actual or imagined) as it would be seen by an observer who looks at the object either in a chosen direction or from a selected point of view. Pictorial sketches often are more readily made and more clearly understood than are front, top, and side views of an object. Pictorial drawings, either sketched freehand or made with drawing instruments, are frequently used by engineers and architects to convey ideas to their assistants and clients.
In making a pictorial drawing, the viewing direction that shows the object and its details to the best advantage is chosen. The resultant drawing is orthographic if the viewing rays are considered as parallel, or perspective if the rays are considered as meeting at the eye of the observer. Perspective drawings provide the most realistic, and usually the most pleasing, likeness when compared with other types of pictorial views.
Several types of nonperspective pictorial views can be sketched, or drawn with instruments. In the isometric pictorial, the direction of its axes and all measurements along these axes are made with one scale. Oblique pictorial drawings, while not true orthographic views, offer a convenient method for drawing circles and other curves in their true shape.
In order to reduce the distortion in an oblique drawing, measurements along the receding axis may be foreshortened. When they are halved, the method is called cabinet drawing.