Tactical Path Finding in Urban Environments Arno Kamphuis, Michiel Rook, Mark H. Overmars Department of Computer Science, Faculty of Science Utrecht University, Padualaan 14, 3584 CH Utrecht, The Netherlands Telephone: +31 30 2531454, Fax: +31 30 2513791 E-mail: arnok@cs.uu.nl, mlrook@cs.uu.nl, markov@cs.uu.nl Abstract In this paper we address the problem of finding paths for small groups of characters in an urban environment taking tactical information into account. This approach presents a way to plan the paths using an existing road map and extending this to a network of corridors. The road map is searched for a globally useful path, after which the corresponding corridors are traversed to find a tactically sound path for all characters in the group. Our approach is capable of utilizing nearly 100% of the available free space in the environment, including almost all tactically useful locations. The generated paths for the group of characters are realistic in the sense that they mimic paths that real humans would follow. After a pre-processing step, the approach is able to produce the paths in real-time. Keywords Games, Path Finding, Tactical Information, Formations 1. Introduction Advanced games and simulation environments need to be able to plan/generate paths for a large number characters. In order to retain the suspension of disbelief [19] for users these paths should be believable or realistic. However, this is not an easy task, especially when tactical information is needed. In this paper we focus on finding paths in tactical training simulations and games. In order to do this realistically we need to rely on military tactics, techniques and procedures. These tactics, techniques and procedures are documented in the so-called ”doctrinal” literature. This literature covers four main areas: • Military doctrine Fundamental principles by which the military forces, or elements thereof, guide their actions in support of objectives. • Tactics The employment and arrangement of forces in battle. • Techniques How to carry out tactics. • Procedures How to perform tasks.