KeyGML Q and A

What is OS MasterMap ?

The Ordnance Survey now provide the definitive digital map of Great Britain as their OS MasterMap product. This seamless database (no more tiles) reflects the real world with themed feature layers, polygon data and the important TOID (unique Topographic Identifier for every feature). OS MasterMap is replacing the old Land-Line product.

How is the data supplied ?

OS MasterMap is supplied as "chunks" in .gz files which are the compressed version of .gml files (Geography Mark-up Language). Only the data required may be selected by area and theme when you want it. Latest updates are available as change only files. Note that .gml files can be very large indeed.

How do I read OS MasterMap into AutoCAD ?

KeyGML has been developed by KeyTERRA-FIRMA Ltd. to read OS MasterMap .gz and .gml files and provide a structured, selective and intelligent input to AutoCAD.

What is KeyGML ?

KeyGML is AutoCAD application software that works within the AutoCAD 2006, 2007, 2008 and 2009 platforms (including AutoCAD Map but not the LT versions) to read OS MasterMap .gz and .gml files and to draw the mapping data within the AutoCAD drawing.

I have my whole Authority area stored in tiles as 1:1250 / 1:2500 .dwg files - can I continue to work like this ?

It is very common for AutoCAD users who need OS mapping to have translated Land-Line data purchased as .ntf or .dxf files into individual drawing tiles and manage these with a product such as AutoZoom Pro. Following user requests after the introduction of the initial release of KeyGML the Batch mode option was added to enable the automatic production of 1:1250 or 1:2500 tile drawings from a whole set of OS MasterMap chunks.

I am only interested in "Land-Line type" mapping for my specific project area - how can KeyGML help ?

Traffic Engineers and Landscape Architects for example may only need coverage for a specific project. KeyGML will populate the AutoCAD drawing (from one or more OS MasterMap chunks) only with data defined as being within a closed 2D Polyline. Data may also be extracted from buffers defined from road centres for example.

What are the main features of KeyGML ?

* One or a number of .gz or .gml files (chunks) may be selected for multiple input.

* Removal of identical TOIDS (note that features crossing the edge of a chunk are not "trimmed" and may be in more than one adjoining chunk).

* Polygons represented as closed polylines or solid hatch.

* OS feature codes to AutoCAD layers and blocks (symbols) by user controlled settings.

* Input by specified themes and groups.

* TOID recognition (and other attribute data such as areas)

* Change only update file input.

* ITN input.

* Link to ADDRESS-POINT (e.g. extract area of interest defined by post code)

* Tools to help with the transition from Land-Line tile based data.

* Printed manual and on-line help system.

* Desktop (dongled) and Network (NLM) versions of KeyGML are available.

How long will KeyGML take to read my OS MasterMap files ?

Bearing in mind the size of some .gml files the following will give an idea of performance :-

P4, 2GHz, 512 Mb. RAM, Windows XP.

102 Mb file takes just over 1 minute to read and less than 3 minutes to create a 10 Mb AutoCAD "Land-Line type" drawing.

Note that the intention is not to create large AutoCAD drawings as KeyGML enables input selection by area(s) of interest and features only.

Are there any other technical considerations ?

Yes. Here are some additional points :-

* KeyGML for AutoCAD 2005 or 2006 is not able to read compressed files directly but we recommend Picozip by Acubix or similar ZIP utility that has a batch feature enabling you to uncompress unlimited number of files in one go, ready to be processed with KeyGML.

* Following a very simple installation routine KeyGML may be run from its own desktop shortcut. The program directory is added to the AutoCAD Support File Shortcut Path and the KeyGML menu loaded.

* It is not practical to apply the Change Only Update option to hundreds of tiles created by the Batch mode option.

What does KeyGML cost ?

Initial copy: £800.00

Subsequent copies: £250.00

5 copies with NLM: £2,000.00

Annual Service Agreement renewal (per site): £200.00

Who has written the software and where do I get it from ?

KeyGML has been created by KeyTERRA-FIRMA Ltd. who are a member of the Key Systems Group of Companies. Key Systems are Ordnance Survey Licensed Developers and Autodesk Authorised Developers.