Topics: Sphere, Vincenty, Geodesic, Great Circle, Spherical Triangle, Polygon, Centroid, Center of Mass, Vector, Area, Haversine Description: This extension includes a large suite of tools for calculating geometric attributes of vector features and for selecting and naming graphics. All tools are available at the ArcView license level. Among many other functions, this extension offers tools for calculating the true area and centroid of polygons as they lay on the sphere, thereby avoiding errors caused by projection distortions. This extension also offers tools to calculate true lengths of polylines as they lie on the spheroid, using Vincenty’s equations. This manual thoroughly explains all algorithms used to calculate geometric attributes on the sphere and spheroid. This extension also includes a tool to create a new shapefile from within ArcMap, either by creating an empty shapefile or by converting graphics. Output: Several tools produce point, multipoint, polyline or polygon shapefiles. Some geometry tools produce new shapefiles while others add new fields to attribute tables. Recommended Citation Format: For those who wish to cite this extension, the author recommends something similar to: Jenness, J. 2011. Tools for Graphics and Shapes: Extension for ArcGIS. Jenness Enterprises. Available at: http://www.jennessent.com/arcgis/shapes_graphics.htm Requires: ArcGIS 9.1 or better (at any license level) or ArcGIS 10. The 'Build Polygon' function requires ArcView 9.2 or newer. This extension has not been tested with ArcGIS 9.0, and I am sure it will not work with ArcGIS 8.x. For detailed instructions on installation and operation, view the on-line PDF version of Tools for Graphics and Shapes Manual Source.