Integrated Transport Network

ITN is part of OS MasterMap and is provided to most public authorities under their Mapping Services Agreement, but until now it has not been well used because of a lack of software to display and interpret it. It contains a wealth of information about roads, their categories, and traffic restrictions such as one-way streets and banned turns. RouteMap displays these by means of coloured lines, with the full ITN data for any link just a mouse click away.

RouteMap includes network analysis functions to find the best vehicle path between any two points, and to produce isochrones or ‘isolines’ – the routes within a particular time or distance of a location. A to B routing can include intermediate points and blockages. The paths generated may be used in other applications, for example to provide a buffer around a route for accident analysis or to generate a catchment area.

Translation of ITN data

RouteMap works with GML or compressed GZ files, translating them intelligently into MapInfo tables. The line styles, format, file names and locations may be changed, but the defaults provide a sensible structure for most users.

Traffic sign symbology

Using our experience and understanding of traffic orders and their signing, we have added the appropriate regulatory and warning signs to the display, making restrictions readily apparent and easy for non-specialists to interpret. Compulsory and banned turns may also be shown as bent arrows to make it clear exactly which movement is affected.

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Traffic sign symbology (cont)

Signs even have plates under them where this is needed to correctly indicate the restriction concerned. Equally we intelligently filter out most signs that are not present on site, despite being recorded or implied in ITN. RouteMap understands where a traffic order would be needed.

Visualisation of ITN data

RouteMap displays the ITN network colour coded by road type:

• Motorway

• Trunk

• Other primary routes

• Class A, B or C

• Minor roads

• Local roads

• Other roads

• Pedestrianised streets

• Restricted access roads

Routing and analysis

RouteMap provides the following route generation and analysis, in each case generating a feature that may be used in any MapInfo function (such as buffering) or in other software.

• Find vehicle paths between any two points on the network, taking account of turning restrictions and one-way streets.

• Find vehicle paths from A to B passing through intermediate points or avoiding temporary obstructions.

• Identify all the roads within a particular driving time or distance of a location of interest.

• Colour-code the map by driving time or distance from a point of interest.

• The distances used may be actual road lengths or with a user-defined penalty applied to less suitable road types.