Object Semantics

The semantics of a digital map object contain attributes (properties, metadata) of the object, similar to database fields. Unlike a database table, different instances of objects within the same layer can have different sets of attributes, and some attributes can be repeated with different values. For example, one object of the "forest" type may have an attribute "vegetation type" with the value "pine" and an attribute "average tree thickness," while another object of the "forest" type may have an attribute "vegetation type" with the value "birch" and an attribute "vegetation type" with the value "fir" without specifying tree thickness.

Object semantics consist of a semantic characteristic code and its value.

Object semantics can be mandatory (affecting the appearance, also mandatory), optional, general, service, or repeatable.

Values for mandatory semantics must always be assigned to the object. When semantics affecting the appearance are changed, the object's conventional sign (symbol) automatically changes.

Optional semantics may be left unfilled for individual object instances.

Assigning semantics to an object is performed using the Classifier Editor tools.

General semantics can be assigned to any object on a vector map.

Service semantics are usually general, have fixed numeric codes, and predefined purposes.

For example:

31001 SIGN DISPLAY SCALE IN PERCENT

31002 SIGN DISPLAY COLOR RGB

31003 FONT HEIGHT IN MM

31004 FONT NAME

31007 OBJECT COLOR WEIGHT IN PERCENT

31017 VECTOR SIGN ROTATION ANGLE

31109 LABEL TEXT IN CLUSTER

31201 STREET NAME

31202 HOUSE NUMBER

31203 BUILDING NUMBER

31204 STRUCTURE NUMBER

31205 PROPERTY NUMBER

31206 STREET CODE

31207 CITY (SETTLEMENT) NAME

31208 CITY (SETTLEMENT) CODE BY OKATO

31209 POSTAL INDEX (ZIP CODE)

32798 OBJECT IDENTIFIER IN DATABASE

32799 OBJECT IDENTIFIER GUID

32800 OBJECT CLASSIFICATION CODE

32801 FLAG FOR OBJECT HAVING A LINK TO A SUBORDINATE OBJECT

32802 FLAG FOR OBJECT REFERENCED BY A MAIN OBJECT

32803 FLAG FOR OBJECT BELONGING TO A GROUP OF EQUAL RIGHTS OBJECTS

32804 LINK FROM OBJECT TO LABEL

32805 LINK FROM LABEL TO OBJECT

32850 OBJECT CREATION DATE (or DATE-TIME of object creation, if this type is set in RSC for code 32850)

32851 OBJECT CREATION TIME (not used if code 32850 is of DATE-TIME type)

32852 OPERATOR NAME

32853 OBJECT UPDATE DATE (or DATE-TIME of object creation, if this type is set in RSC for code 32853)

32854 OBJECT UPDATE TIME (not used if code 32853 is of DATE-TIME type)

32855 UPDATE OPERATOR NAME

32859 UTC START DATE (automatically calculates the number of days from the specified date to the current date with a sign — for planning systems)

32860 LABEL TEXT UTF-16, LONGER THAN 126 CHARACTERS

32861 OBJECT COMMENT

Object semantics are filled according to their type, specified in the digital classifier of the vector map. The value of a semantic can be a string, number, date, color, file reference, URL link, GUID, classified value from a reference list, a computed mathematical formula, or a programmed numeric or string formula (composite string). Programmable semantics are implemented through external dynamically linked libraries.

User semantics are used to record arbitrary object properties not described in the list of semantics in the RSC classifier. User semantics can be created during the import of vector data (SHP, KML, MIF, DXF, WFS, GML, JSON, and others) when field names (keys) of object attributes are not found in the selected RSC classifier. To support such semantics in various tasks (Map Editor, Map Calculations, Object Search, and others), temporary semantics with codes in the range of 660000 and above are created in the RSC classifier for the duration of the GIS session. The semantic name is filled based on the field name in the source vector data. This enables working with user semantics and semantics from RSC in a common list across various tasks. When several maps with the same classifier are opened simultaneously, the list of temporary semantics will be supplemented with user semantics from all maps. When opening different map combinations, temporary codes may have different values in different sessions.

When exporting vector maps to SXF and TXF files, user semantics are recorded with code 32862 and data entries in the format "field_name:value". During import, such semantics are converted back into temporary semantics with the addition of a new code in RSC.

On the map, semantics are recorded with codes in the range of 60000 and above. The correspondence between the semantic code on the map and the field name is stored in the map metadata. When opening a map, temporary semantics are automatically added to the RSC based on the list of field names of user semantics.