regionof

Regionof is not a fixed language construct but a generic term used in programming libraries and mathematical descriptions to denote an operation that yields a region associated with an object or dataset. The precise meaning of regionof depends on context: it may refer to the smallest region containing an object, a region of interest used for further processing, or a user-defined region selected by a criterion. Because there is no universal standard, regionof semantics and return types vary by domain and library.

In computational geometry and computer graphics, regionof(shape) commonly returns a Region instance that represents the shape's bounding region, often the axis-aligned bounding box or a minimal enclosing rectangle. In image processing, regionof(image, mask or criterion) can produce a mask or a set of coordinates that delineate the region of interest (ROI) for subsequent analysis. In spatial databases and GIS, regionof(lon/lat, radius) might define a circular region or a polygonal region around a location.

Return values typically support common region operations such as containment tests, intersection checks, area calculations, and bounds queries. See also ROI, bounding box, and region in mathematics. While regionof appears in multiple ecosystems, users should consult the specific library’s documentation to understand exact inputs, return types, and performance characteristics.