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Polygon Overview


Within a spatial framework, it is often necessary to select certain items or identify a particular area in space. SADA allows the user to draw polygonal shapes for defining areas and selecting items in space. Polygons are very flexible and can be used for defining irregularly shaped spaces. The polygons need not be convex; however, it is important for their boundaries to not cross each other. When a polygon is drawn, items or space located inside the polygon is selected. While the polygon is present, only the items or space within the polygon will be utilized in the analysis.