Armchair explorers who soar over 3D cityscapes on their computer may be used to the idea of maps with an extra dimension. But they are now getting accurate enough to offer much more than a preview of your next holiday destination. Accurate, large-scale 3D maps could soon change the way we design, manage and relate to our urban environments. As part of a project at the Ordnance Survey (OS), the UK government's mapping agency, to demonstrate the potential of 3D mapping, the coastal resort of Bournemouth in southern England has probably become the best-mapped place on the planet. Lasers were fired at the town from the ground and from the air to capture the height of buildings, trees and other features, using a technique called Lidar. Adding information from aerial photos and traditional surveys produced a full-colour 3D map, built up from more than 700 million points. The map is accurate to 4 centimetres in x, y and z - by comparison 3D structures in Google Earth are accurate to about 15 metres. OS is not the only organisation to be exploiting improvements in the hardware and software needed to capture and model cities in 3D. Detailed digital 2D maps, like those the OS maintains of the UK, already underpin the everyday activities of businesses and governments the world over.
They are annotated and overlaid with everything from the layout of electric cables to data on air pollution. Companies are now building large-scale 3D maps to be used in the same way. Now it's not just buildings, but floors within the building that could be annotated. The new generation of maps can capture details like mailboxes and lamp posts too small to appear in existing city-scale virtual maps. Infoterra, a firm based in Leicester, UK, supplied 3D data used in Google Earth, and will launch its own 3D city-mapping service, Skape in January 2010. It also uses Lidar to capture the heights of buildings and other features, and uses aerial images taken from a low angle to provide surface detail at a spatial resolution as low as 4.5 centimetres. Competition between Google Earth and Microsoft's Virtual Earth to wow home users with 3D maps is partly responsible for the maturing of large-area 3D maps. But even as this technology goes pro, consumers may still have a role to play. Google's newly launched Building Maker allows any web user to translate an aerial photo in Google Earth into a 3D building. The results are less accurate than a Lidar-based map. But flying planes to get laser data is not cheap, so crowd-sourcing may be necessary outside commercial and urban areas. Future maps may still need help from enthusiasts more interested in eye candy than urban planning.
More information:
http://www.newscientist.com/article/mg20427366.400-3d-mashup-maps-let-you-edit-the-world.html
More information:
http://www.newscientist.com/article/mg20427366.400-3d-mashup-maps-let-you-edit-the-world.html