Hidden-line elimination:

This skeletal view is called as Wire-frame Model. Although not a realistic representation of the object, it is still very useful in the early stages of image development for making sure that all the corners and edges are where they should be. For some situations such as preliminary designs, centre-line diagrams of structural frames, so on. these are not only quite' sufficient, but even preferred over the more realistic views.

Sometimes, for checking during image creation, or for easier interpretation of the final display, hidden lines and surfaces are not completely omitted, but shown as dashed or lighter lines. It is called as Partial Wire-frame.

The most realistic view, of course, is the one that our eyes would see, namely with the hidden lines and surfaces completely removed. Thus, for realism in 3-D representation, the lines and surfaces which are hidden by the surfaces visible to the observer should be rubbed out or covered up, or better yet, not drawn in the first place, removed from the plotting data by a computer graphics algorithm.

Hidden-line elimination refers to wire-frame diagrams without surface rendering and polygonal surfaces along straight edges. Hidden-surface removal refers to all of kinds of surfaces, involving curved ones. For the simplified and conceptual treatment planned herein, we shall use the phrases "hidden-line" and "hidden-surface" interchangeably.