The wireframe of a surface patch is produced by displaying its
boundary curves and a number of other iso-parametric curves in both
parametric directions, as depicted in Fig.
8.1. Small-scale wireframes on raster screens
provide only a rough idea of the underlying shape and are not very
appropriate means to judge the nature of the surface and its
smoothness and fairness. Furthermore, depending on the density of
iso-parametric lines and their actual shape, they may mislead the
designer about the actual shape of the surface.
Figure 8.1:
Wireframe model of bicubic B-spline patch
