Vector mapping is a digital representation of topographic map features with attributed points, lines and polygons. OSNI Large-scale vector product contains 190 feature types or levels, known as attributes.
Key features
- complete coverage of Northern Ireland, with rural areas surveyed at 1:2,500 scale and built up urban areas surveyed at a more detailed scale of 1:1,250
- contains height information including spot heights and bench marks - all heights are above mean sea level at Belfast
- the rich topographical data model and structure allows interactive access to information on features and makes large-scale vector suitable for a wide range of spatial queries
- other vector, raster and address data, including the user's own datasets, can be used to increase functionality for example vector mapping can be overlaid with orthophotography using suitable software
- projection consistent with other OSNI mapping data
- all data fixed on the Irish Grid and capable of transformation to other reference systems
- supplied either as pre determined tiles or as a bespoke clip out centred on a site specific area
Technical Information
- vector data format
- represents the real world in an organised and consistent way, according to a logical series of rules
- contains 17,335 individual tiles, each based on the original large-scale maps of Northern Ireland surveyed at either 1:1,250 or 1:2,500 scales
- every tile is edge-matched across the whole country, enabling the build up of a complete coverage
- information can be stored for each individual piece of geometry, enabling links to the user's own data
- scale free, can be viewed at a range of zoom scales without any loss of clarity
- available in a range of data formats: - NTF, DXF and DWG
- ESRI GDB and MapInfo TAB formats available for full Northern Ireland coverage only
- detail is being constantly updated by OSNI
- typical file size per tile 1MB
- area covered by 1:1250 tile 0.6.km x 0.4km
- area covered by 1:2500 tile 1.2km x 0.8km
- bespoke user-defined area available
Applications
- spatial queries
- geo-demographic analysis
- distance and area measurement
- property conveyancing
- planning and resource management
- land registration
- generation of paper products and bespoke cartographic representation