12 Geographical Data Visualization on Mobile Devices
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information results in a bigger dot. In addition, if the user moves fast, a greater portion of the map is presented to help the users orient themselves and the amount of
information about buildings is reduced.
In general, using a map for orientation implies a mental effort to switch between
the egocentric perspective of the viewer and the geocentric perspective of the map.
The effort is smaller if the map is forward-up (the top of the map shows the environment in front of the viewer) rather than north-up (the top of the map always
shows the northern part of the environment). Indeed, as shown by various studies
(e.g. [18, 34]), the number of navigational errors is lower with a forward-up map
compared to a north-up map. Moreover, forward-up maps allow the users to better
understand their orientation and to reach targets faster [33]. A further investigation
on the orientation of mobile maps has been carried out by Winter and Tomko [37]
who argue that it is more intuitive for the users to find their actual position at the
bottom of the map rather than at its center, where their positions are typically shown.
Indeed, by looking down at the device in their hand, the users perceive the bottom of
the map as the closest part to their body, and the map as showing all features in the
space ahead of them. This suggests a map design that moves the user’s position to
the bottom of the mobile map to reduce the cognitive workload of map reading.
12.3.2 Perspective Views and 3D Map-based Techniques
In recent years, some attempts have been made to explore the use of perspective
maps and 3D graphics to communicate geographical information on mobile devices
for navigation purposes. Perspective views (Fig. 12.8) are based on showing maps
with an inclination that should make it easier for users to match what they see in the
display with their view in the real world.
Fig. 12.8. Perspective views: maps are inclined to make it easier for users to match what they
see in the display with their view in the real world. Source: iGO Website
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information results in a bigger dot. In addition, if the user moves fast, a greater portion of the map is presented to help the users orient themselves and the amount of
information about buildings is reduced.
In general, using a map for orientation implies a mental effort to switch between
the egocentric perspective of the viewer and the geocentric perspective of the map.
The effort is smaller if the map is forward-up (the top of the map shows the environment in front of the viewer) rather than north-up (the top of the map always
shows the northern part of the environment). Indeed, as shown by various studies
(e.g. [18, 34]), the number of navigational errors is lower with a forward-up map
compared to a north-up map. Moreover, forward-up maps allow the users to better
understand their orientation and to reach targets faster [33]. A further investigation
on the orientation of mobile maps has been carried out by Winter and Tomko [37]
who argue that it is more intuitive for the users to find their actual position at the
bottom of the map rather than at its center, where their positions are typically shown.
Indeed, by looking down at the device in their hand, the users perceive the bottom of
the map as the closest part to their body, and the map as showing all features in the
space ahead of them. This suggests a map design that moves the user’s position to
the bottom of the mobile map to reduce the cognitive workload of map reading.
12.3.2 Perspective Views and 3D Map-based Techniques
In recent years, some attempts have been made to explore the use of perspective
maps and 3D graphics to communicate geographical information on mobile devices
for navigation purposes. Perspective views (Fig. 12.8) are based on showing maps
with an inclination that should make it easier for users to match what they see in the
display with their view in the real world.
Fig. 12.8. Perspective views: maps are inclined to make it easier for users to match what they
see in the display with their view in the real world. Source: iGO Website