Limitations of Wire-frame Modeling:

Though wire-frame modeling is straightforward and simple in concept, it contains a number of restrictions as given below.

• From the viewpoint of engineering applications, this is not possible to measure mass and volume properties of a design. Other applications, such like NC path production, cross-sectioning, & interference detection also encounter difficulty while wire-frame modeling is utilized. Because the wire-frame model database has just low-level information such as lines and points, the wire-frame methods are restricted in scope while high-level information is needed by particular applications such as procedure planning.
• In the wire-frame, the virtual edges (profile or silhouette) are not typically provided. For instance, a cylinder is defined by three edges, i.e., two circles and one straight line. However the straight line is not sufficient to represent the profile or silhouette of a cylinder.
• There are various wire-frame representation schemes. But, ambiguous representations of real objects might be created. For instance, the wire-frame model, illustrated in Figure 2(a), might be recognized as either a block or an inward corner. Figure 2(b) might be considered as either a boss or a hole. Figure.2(c) is only a nonsense object.
• The formation of wire-frame models typically involves more user attempt to input essential information than that of solid models, especially for big and complicated parts. For instance, let the creation of a 3-D model of a simple cube. In the wire-frame model, we have to draw 12 lines, while with solid modeling technique a cube might be formed by providing the location of three corner points. In addition, the latter model gives more information, such like outside or inside of the part.

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