The entity records written out by the CCOGIF mirror those obtained from the reader. The ccogif_XXX attributes must be defined to be meaningful before the feature is written to the output file. If a feature is passed into the writer with an attribute named “ccogif_record_code”, the value of that attribute is inspected to see if it contains one of the values: ccogif_point, ccogif_line, or ccogif_area. If this attribute does not exist, the geometry type of the feature is used to determine which type of entity is to represent the feature.
No topology is normally created by the CCOGIF writer when writing entities to the CCOGIF file, except when polygon data is written to a area themes. In this case, a coverage is computed by intersecting the boundaries and holes of all polygon and donut features written to the group. The coordinates for the lines delineating the resulting areas are written out as LFLR records to the group’s “generic” linear data theme, and the AFLR records are written to whatever theme the original polygons were directed at.
If some other topology is required, it can be defined through other means (that is, elsewhere in the mapping file or by an external tool) and presented to the writer as ccogif_XXX attributes on the entity features. This would require, however, that every aspect of the CCOGIF entity, including the entity ID and any other internal references, be correctly defined on the feature before it makes its way to the CCOGIF writer.