fxarc: ESRI ARC/Info Coverages

A coverage-based translator, converting to nodes, polylines, polygons and text with or without column attributes.

The system is directory based, each directory known as a workspace containing sub-directories known as coverages which in turn contain tables. Multiple workspaces can be open, and selection is done on tables across all coverages. Coverages have no inherent symbology, so the default symbology will be assigned to all graphic primitives.

Currently version 6 and 7 coverages are handled but only tables with associated column information (i.e. those with entries in the “info” sub-directories) are selectable.

Nothing is known about the projection or units of measure of ARC/Info coverage data. These must be set by the client if required.

Extensions to Standard Commands

open/close

open | close <dir> ...

Multiple workspaces can be open for selection at a time.

select

select {* | <column>, … } from <table> where <conditions>

Selection can be on all, none or selected column attributes.

Additional Commands

point_column

point_column <column_name>

When retrieving point data, the default action is to create marker (node) graphic primitives. This command specifies a column from the non-graphic meta data, whose text values are to be used to create text primitives instead of marker primitives.

point_text

point_text <text>

When retrieving point data, the default action is to create marker (node) graphic primitives. This command specifies a constant text value to be used to create text primitives instead of marker primitives.

query_coverages

query_coverages { <client_string_array> }

Returns to the client the names of all unique coverages in all “open” workspaces. If no parameters are supplied the information will simply be printed on the client.

query_tables

query_tables { <client_string_array> { <client_string_array> } }

Returns to the client the names and types of all unique tables in all coverages in all “open” workspaces.Possible values for table types are type are point, text, arc, node and polygon. If no parameters are supplied the information will simply be printed on the client.

query_workspaces

query_workspaces { <client_string_array> }

Returns to the client the names of all “open” workspace directories. If no parameters are supplied the information will simply be printed on the client.

Entity Translation

The following table gives the mappings between the various ARC/Info feature classes,
their ARC/Info feature attribute tables (FATs), and the Eim entity types which the translator produces to represent them:

The following ARC/Info feature classes (and corresponding feature attribute
tables) are not handled:

section <coverage>.sec<subclass>
route <coverage>.rat<subclass>
region <coverage>.pat<subclass>