Autodesk 15606-011408-9320 User Guide - Page 169

Glossary access key An alphanumeric string used by Autodesk MapGuide Server to determine whether a map layer has permission to gain access to a resource. In the Autodesk MapGuide Server Admin, you can assign one or more access keys to a resource. Then, when a map author sets up a layer to use that resource, the author must type one of the valid access keys in the Map Layer Properties dialog box. arbitrary XY coordinates Coordinates that have no corresponding latitude and longitude values. An arbitrary XY coordinate system is suitable for floor plans or very small sites. attribute data Alphanumeric data that describes the characteristics of map features. Attribute data is maintained in tables and databases, which are linked to map layers in Autodesk MapGuide Author. Examples of attribute data include street names, building addresses, land-use codes, and population counts. Attribute data is used either to label map features, create themes, or generate reports. See also spatial data. attribute table See database and table. BNA file format A data format that includes files created in ESRI Atlas GIS. You can convert these files to latitude/longitude SDF files using the Autodesk MapGuide SDF Loader. bookmark A saved view position and zoom magnification identified by a URL that you specify. When you use a bookmark, the map is redrawn at the view position and zoom magnification saved in the bookmark. buffer A polygon that locates its boundaries at a certain distance from a point, line, or other polygon. An example of a buffer is a polygon whose boundaries are 200 feet from the bank of a river. centroid A point designated as the center of a polygon. A centroid is typically computed using information derived from the boundary of the polygon. Computed centroids generally lie within the polygon, but they can also lie outside of the polygon. CGI Common Gateway Interface, an interface that allows server applications to work with web servers. You can use the CGI version of the Autodesk MapGuide Server Agent to work with either Microsoft Internet Information Server or a Netscape Internet Server. character spacing ratio The ratio of the distance between text characters to average character width. For example, if the distance between text characters is 3.5 mm, and the character spacing ratio is 0.5, the average character width is 7 mm. coordinate system Any of a number of reference systems used to define the unique location of a point in space and to reference point, line, and area information by defining its geographic location. A coordinate system is usually defined by a projection, an ellipsoid definition, a datum definition, one or more standard parallels, and a central meridian. Glossary | 169