Figure 5.17 types of projection
In both multi view projection and axonometric projection, the
observer is considered to be at infinity, and the visual rays are
perpendicular to the plane of projection. There fore, both are
classified as Orthographic Projections.
In Oblique projection, the observer is considered to be at
infinity, and the visual rays are parallel to each other but
oblique to the plane of projection.
In Perspective, the observer is considered to be at a finite
distance from the object, and the visual rays extend from the
observer’s eye, or the station point (SP), to all points of the
object to form a so-called “cone of rays.”