This is a text file that contains a large number of predefined Feature Codes for point, line, and text features. The Master File associates point features with symbols in the CARIS Symbol File, text features with fonts in the CARIS Font Definition file, and line features with symbolization patterns in the Master File itself. The effect that these associations have on the display of persistent data depends on whether that data is ESRI or CARIS format.
For CARIS data, every feature has a Feature Code. Thus, CARIS points, lines, and text are associated with symbols, symbolization patterns, and fonts, respectively, via their feature codes, if those feature codes are defined in the Master File. By default, use of the symbolization patterns is turned off in the SDM, and can be turned on via the method MapAPI.setSymbolizationOn.
For ESRI data, there are no feature codes. Thus, there are no built-in associations. However, an ESRI point-feature layer can be associated with a Feature Code in the Master File (and thereby a symbol), via the Data Profile. ESRI line-feature layers cannot be associated with a symbolization pattern at the present time, and there are no text features, as such, in ESRI files. (Text can be placed in ESRI layers using the annotation concept, again via the Data Profile.)
Various API methods create transient features. These methods all take a Feature Code as an argument. This feature code determines (via the Master File) the symbol for point features or the symbolization pattern for line features. (Symbolization for line features must be turned on in the Map, in order for these patterns to be displayed.) Transient text features do not use the Master File. It is strongly recommended that feature codes used in creating transient features be from among those defined in the Master File.
Is is also recommended that the Master File not be changed. If you need special feature codes or symbols, talk to RITI.