Finding your way across an unfamiliar city is a challenge for most people's sense of direction. Software that generates personalised maps showing only relevant information, and carefully chosen views of selected landmarks, could make disorientation a thing of the past. Thanks to online services such as Google Maps and Microsoft Live maps now contain more information than ever. It is possible to toggle between a regular schematic, a ‘bird's eye view’ that uses aerial photos and even three-dimensional representations of a city's buildings. Those multiple perspectives can help users locate themselves more accurately. Direct routeGrabler's team at Berkeley, working with researchers at ETH Zurich, used a perceptual study of San Francisco from the 1960s to help identify which landmark buildings to include on a map of the city. They found that landmark buildings came in three varieties. These categories were used to give each building in San Francisco a rating on the basis of its score in each of the three categories.
When generating a map, the user can choose to display those landmarks in one of two ways. They can be displayed as straightforward three-dimensional depictions, but that masks the buildings' facades. To provide the user with more information, the team added an oblique projection option, which shows all visible sides of the building. Although the buildings look distorted compared with a regular three-dimensional depiction, it is possible to see all the facades a building presents to the street, including both facades for a building on a corner. But buildings depicted this way can hide some streets. This is avoided by widening the map's roads, and shrinking the height of the buildings so that roads remain visible behind even tall buildings. The user's final decision is to choose the purpose of their map. On a shopping map, all the major shops become semantically important and are included on the map. A food map, by contrast, will show fewer shops but more of the city's restaurants.More information:
http://technology.newscientist.com/channel/tech/dn14562-personalised-maps-s%20%20how-the-view-from-the-street-.html