Remedy

The missing intersection must be found, and the active curves amended so that they intersect. When the surface fails in this way, the patch boundary network is displayed with additional information to help locate the problem. Points between curves are found that nearly intersect, and these are indicated with a star symbol - see Figure 3:127 below. Also, the curve segments either side of one of these points are displayed with a broken line. This is particularly useful for finding problems where multiple curves are all supposed to intersect, but some of them do not.

Figure 3:127. Graphical highlighting of curves that do not quite intersect