Treffer: Development of an application for updating 3D city models by citizens

Location Based Services (LBS), are the ability to find the geographical location of the mobile device and provide services based on this location information. With the concept of LBS, TellMaris focuses on tourists and citizens who travel European countries, especially in a region of the Baltic Sea, and use their mobile devices to get information they need on the move. Since TellMaris project is being developed and its database has been set up by retrieving data from the Shape file, one of the next important steps is to update this 3D city models if some buildings have been changed. The application of this thesis gives users possibilities to change some parameters of the buildings. After the implementation of data updating, users can view the 3D scenes in the neighbor frame with another Java applet, or VRML model could also be created if the user wants to view it in the VRML browser. In order to implement the development of the application in the thesis, which is about to update the 3D city model and create a 3D scene, basic Java/Java3D would be used as the programming language; some geometrical theory about handling the building information, such as calculating bounding boxes, height, triangulation, etc, is the necessary mathematical knowledge for setting up the geometrical models; Oracle 9i, as a DBMS, stores all the values of buildings and offers a safe data environment; web services let this application conveniently be used, because all users in the LAN are welcomed to visit it, even in the internet; and at last, VRML will be introduced for it can also be generated in this application. The application consists of two part: one is the Java applet which communicates with the server, sending and getting information from the server and database; the other part is a frame which shows the 3D Scenegraph and gives a visual impression to the user. Via this application the user will eventually get any needed information about his target building, and he is also allowed to change some parameters of the building and then ...