The MGE Writer writes all elements to the current master file. It extracts the conversion parameters required to translate coordinates from feature coordinate units to internal Units of Resolution (UORs). It also determines the dimension of the master file.
When writing to GG/MGE, one of the Data Source types from ODBC, MDB or ORACLE has to be selected. Against the Database Server Name, an empty database has to specified which the writer uses to write all the tables like mscatalog, feature, etc. For instance, with Access (MDB) as the data source, an empty database .mdb or .accdb file would suffice. When an existing database is used, new records are appended to the existing tables. The username and password are optional and may or may not apply in every case.
A cell library file may optionally be used by the MGE Writer. Cell libraries contain named symbol definitions which can be used to depict point features. If a cell library is specified, the MGE Writer reads in all the cell definitions for later when cell features are output. The MGE Writer can use either 2 or 3 dimension cell libraries, and will automatically convert the cell definitions to be of the correct dimension for output.
The MGE Writer then outputs each FME feature it is given. Most often, a single FME feature corresponds to a single design element. However, some of the IGDS element types cause several elements to be output as a complex unit (with the complex bit turned on). This occurs when a multi-line text object, a cell, or a closed shape or linear feature with more than 101 coordinates is output. The MGE Writer hides all of the details of complex element output.
Tip: Tip: Since coordinates in design files are ultimately stored as integer UORs, it is possible for precision to be lost or overflow to occur when they are output. Care must be taken to ensure that the conversion parameters in the seed file preserve the data precision and range.