In continuation to my introductory post, KDE Marble lacked auto centering feature in Navigation Mode i.e. when the location of the gps device went off the display area, the user had to manually bring the location back to the visual area, which was very inconvenient especially if you are in a car and using Marble for Navigation.
The user now have two options for auto recentering:
1) The gps device location always remains on the center of the map.
Before Auto Centering ( GPS Device Location Represented by arrow on the map)
After Auto Centering the device location is always on the center of the screen.
2) Second, auto centering is done when the gps device reaches a custom rectangular area defined on the visible map area or viewport (which is currently 65% of the area around the center of the map), so that recentering is not performed over and over again.
Before reaching the rectangular area:
When the device crosses the rectangular area, auto centering is performed.
Plan for coming week: 1) Auto zoom in and zoom out functionality is to be added to Navigation Mode in Marble (it's near completion :) ).
2) Routing Instructions are to be shown on the map while navigating.