GTViewer File Types

I am often asked what the different GTViewer file types are. Here is a list of the file types (by extension) with descriptions and where they are created.

A. Main File Types:

.GTM – GTViewer Manager File
- ASCII
- Points to multiple component files (.gtg, .gtn, .flt, etc.)
- Can be opened by GTViewer, GTVx, GTExtract, GTPack
- (Data is view only, user cannot change any values in the data)
- Used to Create Extract (.GTX) and Session (.GTS) files
- Can be shared by any number of users and can be placed on a CD
- Component files can be distributed in multiple directory, drives, etc.
- Component file limit is 2G each

.GTX - GTViewer Extract File
- Binary
- Single, self-contained file with no dependencies
- Can be opened by GTViewer, GTVx, Pocket GTViewer, GTExtract
- Created from a .GTM file or another .GTX file
- Can be created by GTViewer, GTExtractX, GTExtract, GTPack
- When opened directly, they are single user.
- Session information stored in the file (view settings, filter settings, session graphics (redlines).
- Write access must be available to store session information
- Optional Password protection

.GTS – GTViewer Session File
- ASCII
- Points to an existing .GTM, .GTX, or .GTW file.
- Can be opened by GTViewer and GTVx
- Can be created from a .GTM, .GTX, or .GTW file
- Stores only view settings, display settings, session graphics (redlines)
- Multiple session files can be created for the same source data (.GTM, .GTX, or .GTW)

.GTW – GTWeb Extract File
- Binary
- Single file, but defines which GTWeb Object files are required to use it.
- Can be opened by GTViewer
- Created by GTWeb Server or GTConv
- Primary use is for Detail Drawing/Internal Worlds


B. GTM Component File Types:

.GTG – Graphics File
- Binary
- Contains GTViewer Graphics elements and any embedded data for one category
- Can be imported and exported by GTViewer, GTVx, and Pocket GTViewer

.GTN – Spatial Index File
- Binary
- Spatial index for a single .GTG file
- Created by GTIndex or GTConv

.DFN – Font file
- Binary
- Holds font information for one text or symbol font
- Created by GTFont
- Can be modified by GTFontEdit

Color.txt – Color Table File
- ASCII
- Maps color numbers to RGB color values with ranges of 0 to 255
- Created by GTConv or manually

Linestyle.def – User-defined linestyle definition file
- ASCII
- Created Manually

Style.def – Dynamic Style Definition file
- ASCII
- Created Manually

Style.map – Maps Dynamic styles to filter ids and zoom level ranges
- ASCII
- Created Manually

Filter#.FLT – Display Filter Definition Files
- ASCII
- Contains default display settings (display status, min display threshold, max display threshold, selectability) for each filter id in a single category.
- Contains filter id names and group names
- Created by GTConv, GTCreate, or Manually

Data.txt – Tabular Data File
- ASCII
- Pipe delimited data values with table headers
- Created by GTDataConv, FV2ASCII, or Manually

Data.tab – Tabular Data Definition File
- ASCII
- Table header information
- Includes all alternate names, display priorities for tables and attributes

Data.idx – Tabular Data Index file
- Binary
- Created by GTDataConv, FV2ASCII, and GTCreate

Data.ref - Tabular Data Reference File (Framme Data only)
- Binary
- Created by GTDataConv, FV2ASCII, and GTCreate

Query#.qry – Query File
- Binary
- Created by GTQuery

.GTP – Display Filter Preset File
- Created by GTViewer or GTVx

GPSInfo.ini – GPS Coordinate Projection Information
- ASCII
- Created by GTViewer and Pocket GTViewer

DgnExport.ini - DGN Export parameter File
- ASCII
- Created Manually


C. Temporary Files Used to Create the Component File:

Linkage#.Key – Mapping of Feature Keys to Element Position
- Binary
- Created by GTGetKeys
- Used by GTQuery

Query#.txt – Query Definition Files
- ASCII
- Created Manually
- Used by GTQuery

Data.fer – Reverse lookup for Framme Reference features to Master Feature key
- Binary
- Created by GTRefSort
- Used by GTQuery for certain query types