Mark Tibboel Creating high quality indicative routes in heterogeneous virtual environments

In this thesis we will attempt to close the gap between fast grid-based method and -approximation methods that solve the Weighted Region problem. In order to compare both methods, we will define a formula to calculate the -value of grid-based methods and define the bounds of the -value for -approximation methods. Furthermore, we will improve on heuristics for A* grid methods for weighted regions and present an adapted version of the Hierarchical A* method that improves the running times of A* grid in heterogeneous environments. Finally, we present three pruned graph methods that reduce the construction and query times of Steiner-graph methods. Acknowledgements. This research has been supported by the COMMIT/ project (http://www.commitnl.nl/).