MbRegion Region

Class MbRegion is declared in file region.h.

Region MbRegion is a derived class of MbPlaneItem, Fig. 1.

Fig. 1

A region is described by a set of contours contours. The contours of a region are closed and do not intersect themselves or each other. Among the contours of the set, one contour is external and the others are internal and lie inside the external contour. In the set contours the external contour is always the first one.

A region represents a connected set of points of a two-dimensional space whose boundaries are described by two-dimensional closed contours. The contours of a region are oriented so that when moving along any contour, the described point set lies to the left of the contour. That is, the external contour of a region is oriented counterclockwise, and the internal contours are oriented clockwise.

A region is shown in Fig. 2:

Fig. 2

A region is used to describe two-dimensional connected areas. Boolean operations can be performed on regions.