Tuesday, March 29, 2005

COGNET GIS Advisor Newsletter

Check out the COGNET GIS Advisor Newsletter for more information on the GTViewer Family of Products:



March 29, 2005 - Vol. 1, Issue 1

Counting Features with GTViewer

GTViewer provides the ability count features or elements in a polygon. There are several ways to perform counting:

Method 1:

  • Create a polygon with session graphics (redlines). The Rectangle, Shape, or Circle element can be used.
  • Select the session graphic you wish to use for the counting. Use the Draw/Select command (or press the northwest arrow icon on the session graphics toolbar), then click on the session graphic element you wish to use. The session graphic will highlight and vertex handles will be displayed when it is selected.
  • Select Tools/Count to get to the Count Options dialog. This option will only be enabled if there is a single valid polygon element is selected.

Method 2:

  • Use the Attribute Info Mode and review a feature or element.
  • The Attribute Info Dialog box will have a Count button at the lower right if GTViewer can make a closed polygon out of the selected element. Press the Count button to get the Feature Count Options Dialog.

Method 3:

  • Perform a Thematic Query to highlight features.
  • You can select and/or create a session graphic polygon to count in (as described in Method 1) or you can choose to count all highlighted elements (an no polygon needs to be selected).
  • Select Tools/Count to get to the Count Options dialog.

The Count Options dialog is shown below. Depending which method you used from the above list, different options will be available to you on the Count Options dialog. Methods 1 and 2 will always provde the By General Rules and By Feature option. However, if Method 3 is used, you will have the By Highlighted Feature (All) and possibly the By Highlighted Feature (in Shape) option if a polygon was also selected.


The By General Rules method allows you do specify basic conditions that must be met before an element will be counted:

  • Only Features with Attributes – with this option selected, all features in the polygon must have a linkage to database information before they will be counted.
  • Ignore Text Elements – with this option selected, text elements are not counted. For Framme data, this option does not ignore symbols even though they are technically text elements (fonts are designated as either text or symbol and this characteristic will allow symbols to be counted even when text is ignored). This option does not affect the counting of symbol elements.
  • Only Visible Features – with this option selected, only elements that are currently visible will be counted. Visible means that their Category is displayed and the features are not filtered. The elements do not have to be currently in the view to be counted with this option selected, they just have to be in the selected polygon.


The By Feature method allows you to specifically define which feature or features you want to count. You can select more than 1 feature by holding down the Ctrl button when selecting.

The By Highlighted Feature (in Shape) method allows you to count highlighted elements that may result from a Highlight Query or an External Application. This option is only available if a valid polygon element has been selected and Highlighted elements are present (as the result of a Thematic query or a custom application).

The By Highlighted Feature (All) method allows you to count all highlighted elements that may result from a Thematic Query or a Custom Application. No selected shape is required to use this method and this option will be available anytime highlighted elements are present.


Once you have selected the method to use for counting, press the OK button. The counted elements will highlight on the screen as they are counted. When counting is complete, you will be presented with a Count summary dialog. This dialog will show the total count for each feature counted. If the features were linear elements, the total length of the linear elements that fell inside the polygon will also be presented.


The view will highlights all of the features that are in the selected Polygon. Linear elements that pass through the polygon or are only partially contained by the polygon are highlighted appropriately:

You can select an item in the Count summary dialog box and press the Detail button (or just double-click on the item). A Count Details dialog will be displayed showing the primary record for each feature in the selected group. The primary record is the record for a feature with the lowest display priority value.

In the Detail dialog you can select an item and press the Locate button (or just double-click on the item) to locate the specific feature in the current view. The Detail dialog also have several other options:

  • The Info button will display the standard Attribute Info dialog for the selected element.
  • A Copy button is available on both the Summary dialog and the Detail dialog. By pressing this button, the contents of the dialog will be copied to the Windows clipboard. The information can then be pasted into another application like Excel.
  • The Save button will save the information as a Comma Separated Value (.csv) file.

The Count Functionality in GTViewer provides an easy way to gather information about your data. Count results can be easily saved as reports and the graphical results can also be exported to other applications. This is just one feature that lets you get the most out of your data.

Monday, March 28, 2005

Emphasize Session Graphics Mode

All of the GTViewer family of products support a unique command that many users may not be aware of. The Emphasize Session Graphics mode is found under the View menu and is the toolbar button with the red/green/blue stripes fading to gray:


This simple command is a little mislabeled, but it can significantly impact the way you view your data in certain situations. The job it does is very simple; it grays out all graphics except Session Graphics (Redlines) and Highlighted Elements. Highlight Elements are produced by the following:

  • Locate Queries
  • Thematic Queries
  • Feature Counting
  • Custom Applications

The reason I say Emphasize Session Graphics is mislabeled is because it does more than just emphasize redlines; it also emphasizes highlighted elements.

So, what does this mode do for you? It makes it very easy to tell Session Graphics (Redlines) from the rest of the data, and it makes the results of your queries (especially Thematic and Feature Counting) very easy to see amidst all of the other data. In fact, the Thematic Query dialog box allows you to automatically activate the Emphasize mode.

Here is an example of a Thematic Query with and with the Emphasize Session Graphics mode:



Here is the same query is Emphasize Session Graphics turned on:




Thursday, March 24, 2005

Thematic Queries in GTViewer

GTViewer offers a very powerful tool called Thematic Queries (sometimes called Highlight Queries). This posting will describe what this feature does and what it can do for you.

Locate Queries are the type of query most GTViewer users are familiar with. These queries allow the user to key in a search criteria, show a list of matching results, and then graphically locate on a single item in the list.

A Thematic Query is very different. It allows the user to key in a search criteria, but instead of showing the tabular results, it highlights all of the features matching the specified search criteria thereby creating a Theme. The user can specify the color and weight of the Theme. Multiple Thematic Query results can be displayed at the same time and the Emphasize Session Graphic mode can be used to enhance the display of a Theme. The Thematic Query is easier to describe with pictures than with words. The first example below shows a Circuit highlighted in Red. This Thematic Query let the user select from a list of Circuit ID, then let the user pick the color and weight properties.




The following picture shows 3 circuits highlighted in Red, Blue, and Magenta.



The Thematic results are highlighted elements. This fact has some implicit meaning that is worth going over. Besides seeing the visual results of a Thematic Query, you can also:

  • Count Thematic Query Results in polygons (with the Feature Counting command)
  • Convert Thematic Query Results to Session Graphics (with Tools/Convert Highlighted Elements to Session Graphics)
  • Reviewed Results as if they were regular features in the graphics (the original element does not have to be displayed)
  • Print Thematic Query Results
  • Exported Thematic Query Results (to a .gtg or DGN file).

Thematic Queries have a variety of uses. One of the more innovative uses I have seen came from a customer who was Highlighting all elements that had a specific Tax Code property. First, the Thematic results were used to verify that the Tax Code properties were correct. This task is easily done when you can visually see the results as a whole. Second, the Count command was used to create two different reports. For the first report, session graphics shapes were drawn around features that were not in the appropriate Tax Boundary. The Thematic results in the polygons were counted and a report created with the features with the wrong Tax Code property. For the second report, the Tax Boundary shapes were used to count all of the highlighted features to produce a report of all features in the Tax Boundary. The Count reports show the total lengths of linear elements automatically.

Wednesday, March 23, 2005

GTViewer Keyboard Shortcuts

GTViewer can use a variety of Keyboard shortcuts to perform tasks. While this information is in the GTViewer documentation, many users are not familiar with them.

Magnify Mode

Page Up – Increase size of Magnification Area
Page Down – Decrease size of Magnification Area
Esc – End Magnify mode
+ – Zoom In
- – Zoom Out


View History Navigation (not in Magnify mode):

Ctrl-Page Up – Previous Location
Ctrl-Page Down – Next Location


Panning (in any mode)

Left Arrow – pan to the left
Right Arrow – pan to the right
Up Arrow – pan up
Down Arrow – pan down


Selected Element Modification

Shift-Left Arrow – Rotate selected element(s) to the left
Shift-Right Arrow – Rotate selected element(s) to the right
Shift-Up Arrow – Scale selected element(s) up
Shift-Down Arrow – Scale selected element(s) down

Ctrl-Left Arrow – Move selected element(s) to the left
Ctrl-Right Arrow – Move selected element(s) to the right
Ctrl-Up Arrow – Move selected element(s) up
Ctrl-Down Arrow – Move selected element(s) down

Del – Delete selected element(s)

Ctrl-X or Shift-Delete – Cut selected element to clipboard
Ctrl-C or Ctrl-Ins – Copy selected element to clipboard
Ctrl-V or Shift-Ins – Paste selected element from clipboard
Ctrl-Z or Alt-Backspace – Undo Last Drawing command.


Selected Dimension Element Edit Modification

Space - Toggle Dimension Orientation
+ - Scale Dimension Text Up
- - Scale Dimension Text Down
Enter - Toggle Inside/Outside


Selected Leader Line Element Edit Modification

Space - Toggle Arrow Head
+ - Scale Arrow Up
- - Scale Arrow Down

Print to Scale

L – Set to Landscape Orientation
P – Set to Portriate Orientation
+ – Set to next larger scale
- – Set to next smaller scale
Esc – Cancel Print to Scale Mode
Shift-P – Print Preview


Zoom In/ZoomOut (Zoom, Attribute Info, Pan, Magnify, and Extract Modes)

+ – Zoom In
- – Zoom Out

Attribute Info Mode

Ctrl
and Mouse Click – Search for Linked files only.


Keyboard Accelerators

Alt-B - Previous View
Alt-A - Attribute Info Mode
Alt-Z - Zoom Mode
Alt-P - Pan Mode
Alt-F - Fit Data
Shift-Alt-F - Fit Session Graphics
Alt-R - Refresh View
Alt-D - Display Filter
Alt-O - Overview
Alt-M - Magnify
Shift-Alt-M - Measure Mode
Alt-E - Toggle Emphasize Session Graphics
Alt-H - Toggle Hide Raster
Alt-L - Locate XY
Ctrl-N - New Session
Ctrl-O - Open File
Ctrl-P - Print
Ctrl-S - Save Session
Ctrl-V or Shift-Insert - Paste from Clipboard
Ctrl-C or Ctrl-Insert - Copy selected session graphics to Clipboard
Ctrl-Z or Alt-Backspace - Undo Last Redline
Ctrl-X or Shift-Delete - Cut selected redlines to Clipboard
F1 - Help
Shift-F1 - Context Sensitive Help
F6 - Next Window Pane
Shift-F6 Previous Window Pane

Friday, March 18, 2005

Linkages and Embedded Data

The GTViewer Data format supports two different approaches for associating tabular data with graphical elements. This post describes the two approaches in detail.

Linkages

  • Linkages are keys placed on the graphic elements to link them to tabular records in one or more tables.
  • A Linkage can be made up of one or more 32-bit integer values.
  • There are two basic Linkage Types: 1Key and 2 Key. While rarely used, there is also support for 3, 4, 5, and 6 keys systems as well as using 1 key and 2 key with repeat modes so that you can have 6 one key links or three 2 keys links on the same element.
  • The Linkage Type is defined in the ASCII Data Info section in the .GTM file. Types 1 and 3 (genrally used for Framme, MGE, Shapefile, and GeoDatabase data) are 2 Key; types 2 and 4 (generally used with Smallworld and G/Technology data) are 1 Key.
  • Linkages only take up space in an element if they are specified. So, if you are very concerned with the graphics file sizes, do not use linkages on elements you do not wish to link to tabular data. GTConv provides an option drop linkages on categories of data if you wish to reduce the file size.
  • A Category is assigned a Data Id. The Data Id corresponds to one of the tabular datasets defined in the ASCII Data Info section. The dataset assigned to the Category determines how the linkage will be interpreted on the graphics elements (1 Key or 2 Key). More than one Category can use the same Data Id, but one category cannot use more than one ASCII Data Info section.
  • With Framme data, the linkage is 2 Key. The two 32-bit integers used to create the Linkage are from the feature’s RB_PRMRY (gid) and RB_SCDNRY (ufid) values in the tabular data records. It is also possible to merge multiple Framme segments together and still maintain their data integrity by offsetting the GID values by segments (this is handled automatically by the GTData utilities).
  • With Smallworld Data, the linkage is 1 Key. The 32-bit integer used to create the linkage is from the feature’s Object Id value found in the tabular data. However, the 2 Key system is now generally being used to add some additional flexibility.
  • With MGE and MicroStation Data, the linkage is 2 Key. The two 32-bit integers used to create the Linkage are from the feature’s Entity Number and Mslink values. The Entity Number and Mslink values come from the element’s original MicroStation linkage. The Entity number corresponds to the table number (defined in the miscatalog table) and the Mslink value corresponds to the tabular records’ MSLINK attribute values. MGE data require two keys because the Mslink values are not guaranteed to be unique across multiple tables; the entity number ensures uniqueness across the records from all tables.
  • With Shapefile data, the linkage is 2 Key. The two 32-bit integers used to create the Linkage are from the table number (unique number assigned to each table) and the tabular record’s row id. These Linkages work very similarly to the MGE Linkages; the differences are that the table number is contrived and the row id is an implicit mslink value.
  • With G/Technology Data, the linkage is 1 Key. The 32-bit integer used to create the Linkage comes from the G3E_FID attribute on the tabular records. However, the 2 Key system is now generally being used to add some additional flexibility.
  • It is possible to have up to three 2 Key Linkages or six 1 Key Linkages on a single Element. It is very rare than more than a single linkage would be needed; however, this functionality does exist to support unusual source data types.
  • All records with a common linkage from the tabular data will be displayed when an element is reviewed. For example, if a feature has several records from different tables and/or several records from a single table associated with it, all of these records will be displayed when the element is reviewed as long as all of the records have the same key as the element.
  • Examples of 1 Key and 2 Key Linkages are shown below:





Embedded Data

  • An element can have a Linkage and/or Embedded data.
  • Embedded data is a text string embedded in the element itself. A Linkage is a Key embedded in the element that points to data somewhere else.
  • Embedded data can be any string value; however, if it follows a simple format, GTViewer, GTVx, GTWeb, GTSketch, and Pocket GTViewer will interpret the information as a tabular record (just as if it were a Linkage pointing to an actual tabular record).

The format for the embedded data is as follows:

\t Table Name

\a Attribute Name

\v Attribute Value

  • The tabular record string can contain 1 or more table entries (\t).
  • For every \a there must be a \v.
  • All \a and \v pairs will correspond with the preceding \t.
  • If the SessionGraphicsDataStructureFile entry is defined in the .GTM file, display priorities and alternates names will be applied to the formatted embedded data.

    Example:

    \tTestTable\aattr1\vvalue1\aattr2\vvalue2

    Table: TestTable

    attr1=value1
    attr2=value2
    attr3=value3

  • The element structure supports multiple types of embedded data; however, only Type 1 is currently implemented and Type 1 is a basic Text String.
  • The maximum size of a Type 1 Embedded Data string is 2 to the 32nd power (4,294,967,296) characters; however, the practical limit will be significantly smaller.
  • Embedded data provides a very easy method for adding tabular data to session graphics. While this data cannot be processed as efficiently as relational data in a dedicated tabular record structure, it can quiet easily handle most data collection needs.
  • Embedded data can be retrieved from elements via code with GTViewer, GTVx, GTRead, and PGTReportX. There are also GTData utilities that can dump out the data like GTFormatInfo which reads a .gtg file and output all of the embedded data according to supplied formatting templates. Safe Software’s FME is also able to read .gtg files and understands the table structure embedded in the elements.
  • GTViewer can Export embedded data as comma separated value files (with no coding required) and can export the embedded data as XML. Both of these options are available from the Draw/Export/Export Data menu in GTViewer.
  • Embedded Data can significantly increase the size of element. Too much embedded data can degrade performance on slower machines (such as the handhelds).
  • Embedded data can be used in any Category; however, it is generally only used in Session Graphics Categories since it is more efficient to use linkages for large amounts of data.













Thursday, March 17, 2005

GTViewer 4.0.x.14 is Available

GTViewer version 4.0.x.14 is now available. An excerpt from the readme.txt file is shown below:

-----------------------
04.00.00.14 - 03/17/05
-----------------------

- NEW - ApplicationInactivityTimeout entry has been added to the Additional Properties section to specify a number of minutes a document can be inactive before GTViewer will close.

- FIX - Elements that use a style rule to control the weight were not highlighted correctly. The element weight was used instead.

- FIX - Links on features with repeating components would double the entries on the
Link Tab. Seen only when using externally or internally linked files.


Tuesday, March 15, 2005

FME Support

GTViewer provides a variety of tools for converting data into the GTViewer format. GTData contains a variety of tools to convert data; GTConv utility is used for DGN files, GTShapeConv is used for Shapefiles, etc. There is also the GTCreate ActiveX control which is part of the GTViewer SDK that can be used to convert any data into the GTViewer format. This control is used in our G/Technology data conversions and with Personal GeoDatabase conversions. The latest conversion tool for GTViewer is a Reader and Writer Plug-in for Safe Software’s FME (Feature Manipulation Engine). For those not familiar with FME, it is an application that can take one format and convert it to another, and it deals specifically with spatial data such as GIS and AM/FM data. FME reads and writes a large number of formats. By adding GTViewer to the list of supported FME formats, GTViewer no longer has to focus on Intergraph, ESRI, and SmallWorld data; GTViewer is now available for a much broader audience.

FME can be used for more than just creating GTViewer data from another data source. It can also read GTViewer data and convert it to any of the formats supported by FME. Specifically, if you are creating redlines in GTViewer, you can now easily takes these redlines back to a variety of formats; previously, GTViewer could only convert its redlines to DGN, DXF, and XML. The FME Reader for GTViewer will handle all data attribution that has been embedded on redline graphics, so if your data collection process stores attribution on the redlines; this data is handled automatically.

FME is a power and flexible application that allows the user to perform a variety of tasks when data is converted. The data can be reprojected, moved, merged with other data, created from other sources, transformed, etc. FME is generally more interested in the geometry and attributes for the data it translating than the styles used to render the data; however, the GTViewer writer plug-in was designed to easily specify different styles (based on feature type, attributes, or any user-defined differentiator) and take full advantage of GTViewer’s dynamic style system. Also, the Style Manager in GTViewer allows a user to create, define, and edit Dynamic Style rules and mappings on-the-fly to quickly and easily define styles and symbology for a dataset. GTViewer’s support for TrueType fonts, layered symbols, and complex User-defined linestyles allows just about any data to be accurately reproduced in the GTViewer format.

Monday, March 14, 2005

Customizing GTViewer

GTViewer is highly customizable and extendable. You can modify certain aspects of existing functionality or create customized applications that take advantage of GTViewer’s functionality. There are two different approaches to customizing GTViewer and the task you are trying to accomplish determines the approach to take. The two approaches are:
  1. Writing a custom OCX that is called by GTViewer
  2. Writing your own application that uses the GTVx ActiveX control.

There are many differences between these two approaches even though the end results may be very similar.

OCX Approach

Writing a custom OCX for GTViewer is the more limited of the two approaches; however, it generally requires the least amount of development to create a complete application. The OCX approach is ideal for creating applications that perform inspections, inventory, custom queries, and custom display control; however, it can also be used for complicated tasks like tracing. With GTViewer, a custom application appears as a menu item under the Query menu. When activated, GTViewer will create a dialog (modal or non-modal) and insert your OCX into this empty dialog. GTViewer also makes the necessary calls to establish 2 way communications between the OCX and itself (which allows access to data, views, display controls, metadata, etc.).

GTVx

An alternative approach to customizing GTViewer is to use the GTVx ActiveX control to create a custom application or to embed GTViewer functionality into an existing application. GTVx is an ActiveX control that provides GTViewer’s functionality. The functionality of GTVx is nearly identical to that of GTViewer and it also provides additional functionality that is not included in GTViewer (such as a set of data conversion and manipulation methods and the Data Monitor). The GTVx control can be used by writing as little as one line of code; however, it provides no interface other than a right-mouse menu (similar to the one in GTViewer); so it is the custom application’s responsibility to create an appropriate interface. While GTVx’s minimal interface may require some additional coding to create a complete application, it also provides an extreme degree of flexibility when creating custom applications. Also, template applications are available to provide most of the standard GTViewer interface.


Requirements:

OCX: Only license GTViewer, Visual Basic

GTVx: a GTViewer license to run and a GTViewer SDK to develop with, Development Environment supporting ActiveX controls (Visual Basic, Visual C++, .NET).

Suitable Applications:

OCX: Inspections, Inventory, Data Collection, Tracing, or any application that extends the functionality of GTViewer.

GTVx: Applications that need to fit very specific workflows and requirements, existing applications that need GTViewer’s viewing capabilities, tracking applications (for trucks, calls, or outages), and custom printing applications (mapbooks).

Friday, March 11, 2005

GTExtract versus GTPack

A common question I get asked is what is the difference between GTPack and GTExtract. Both of these utilities are delivered as part of GTData and appear on the surface to do pretty much the same thing. However, they are actually very different in how they work.

When using GTViewer, you can create an extract by rectangular fence or by polygon at any time. An extract is a self-contained file with all of the graphic data, tabular data, queries, display settings, redlines, etc. An extract is a .GTX file (see last post for more info on Extracted Files). An extract is a single file, where as non-extracted data (.GTM file and dependencies) is a collection of files.

GTExtract

GTExtract is virtually identical to the Extract Command found in GTViewer. The difference is that GTExtract is run from a Command Prompt and takes keyed in parameters instead of interactively selecting the area to extract. GTViewer’s Extract Command and GTExtract perform the exact same task both resulting in an Extract file (.gtx). GTExtract allows a range to be explicitly defined on the command line or the default range (-dr) can be used. The default range is the same as the Dataset’s range defined in the .GTM file.

GTPack

GTPack has the same options as GTExtract and produces an Extract File (.gtx) as output; however, GTPack differs in that it does not actually perform an extract of the data. Instead, it “packs” all of the component files specified by a .GTM file into an Extract File. The result is usually the same as running GTExtract with the default range option; however, GTPack will outperform GTExtract by a significant margin because it doesn’t have to determine which elements are database records are in the extract range. GTPack always takes all of the data and packs it into the Extract file.

So, if you are going to extract your entire dataset into a single Extract File, it is more efficient to use GTPack than GTExtract. If you want to extract a specific area out of the data, you must use GTExtract.

The GTViewer SDK also includes an ActiveX control called GTExtractX that is equivalent to GTExtract only it is in the form of an ActiveX control that can be used in Visual Basic Application or any development tool that can utilize ActiveX controls.

Unextracted versus Extracted Data

Many people ask what the difference is between Extracted and Unextracted data is to GTViewer. This is a good question because to the end user it appears to be the same. There are different uses for each and I will explain these below:

Unextracted Data (.GTM)

  • Unextracted data is what is created when data is converted to the GTViewer format.
  • Unextracted data always contains a .GTM file and all of its dependencies (.gtg, .gtn, .flt, .dfn, etc.) See previous post for more information on the different file types.
  • The .GTM file is the file you open in GTViewer or the file you create a new Session from in GTViewer.
  • Unextracted Data can be used by GTViewer, GTVx, GTWeb Server, GTPack, and GTExtract.
  • Unextracted Data is never modified by the end-user. It can be shared with any number of users simultaneously.
  • A Session File (.gts) is always created to store user information and redlines when a .GTM file is opened in GTViewer.
  • You can update any of the components of the Extracted Data without updating the entire thing.
  • Incremental Updates are supported with Unextracted.


Extracted Data (.GTX)

  • Extracted Data is single file, the .GTX file. The file is self-contained and includes all graphic data, tabular data, queries, display settings, etc.
  • Extracted data is created by GTViewer (Extract Command), GTVx, GTPack, GTExtract, GTExtractX, and GTWeb Server. GTViewer can create an Extract file by placing a rectangular fence or a Polygon in the map view and then extracts only the data in the specified area.
  • Pocket GTViewer only reads Extract Files. GTViewer, GTVx, GTWeb Server, GTPack, and GTExtract can read Extract Files as well.
  • An Extract File contains a session file and can store all of the user session information such as redlines, display settings, etc. When used in this mode, an Extract file is a single user file. However, a Session File (.gts) can be created with an Extract file too (just like it is with a .GTM file) and will allow a .GTX file to be used by multiple users simultaneously.
    The only data not stored in an Extract File are Raster files and externally linked file.
  • Extract Files support Passwords and data expiration.

GTViewer Competitive Upgrade Offer

Press release from GITA:


Competitive Upgrade for Viewers

MADISON, Ala.— March 7, 2004— Graphic Technologies, Inc. (GTI), today announced competitive upgrades for several widely adopted viewing software products. “Upgrade your current viewer to GTViewer for one year of maintenance at $75 per copy,” said Mike Stokes, president of GTI. “After doubling our software revenue for each of the last two years, we have gained confidence from our customers to offer this competitive upgrade.”

GTViewer offers several advantages:

  • Platform flexibility. Companies using multiple geospatial vendors can standardize on GTViewer for office and mobile needs. A single user interface and a standard set of applications can be used across the enterprise.
  • Vendor flexibility. Looking to change your current GIS platform? GTViewer can be a point of stability during the migration of geospatial engines.
  • Easy to learn. Typical end user training time is 15 minutes for basic operation.
  • Easy to use. Simple and intuitive interface is adored by GTViewer users and envied by those using products clogged with desktop baggage.
  • Speed. GTViewer consistently provides fast response, especially on large data sets.
  • Enterprise friendly. Unite disparate data and systems into a shared standard.
  • Cost. GTViewer annual maintenance for the upgrade is $75 per copy.
  • Customizable. Build powerful applications using VB, VC++, or .NET. Over 150 methods are exposed by GTViewer to simplify development.
  • Power to spare. GTViewer’s robust data model allows sophisticated applications to integrate with the back office geospatial system. Work sketch and costing, inspections, traces, and analysis applications generate impressive return on investment.


    Contact GTI for more details:
    Call Charlie Marlin at (256) 774-5247 or email info@gti-us.com

Thursday, March 10, 2005

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

Wednesday, March 09, 2005

GTViewer Introduction

I am using this medium to provide information on GTI's GTViewer family of products. The focus will of course be GTViewer, but there will also be information on Pocket GTViewer, GTVx, GTWeb, GTSketch, GT/Trace, GTCad, and Pocket GTCad. I hope that this Blog will be useful to all GTViewer users as well as those considering GTViewer as a viewing platform.

Joey Rogers