Marc Herrlich

Classification of Player Roles in the Team-Based Multi-player Game Dota 2

Computer games are big business, which is also reflected in the growing interest in competitive gaming, the so-called electronic sports. Multi-player online battle arena games are among the most successful games in this regard. In order to execute complex team-based strategies, players take on very specific roles within a team. This paper investigates the applicability of supervised machine learning to classifying player behavior in terms of specific and commonly accepted but not formally well-defined roles within a team of players of the game Dota 2. We provide an in-depth discussion and novel approaches for constructing complex attributes from low-level data extracted from replay files. Using attribute evaluation techniques, we are able to reduce a larger set of candidate attributes down to a manageable number. Based on this resulting set of attributes, we compare and discuss the performance of a variety of supervised classification algorithms. Our results with a data set of 708 labeled players see logistic regression as the overall most stable and best performing classifier.

Exergames for Physiotherapy and Rehabilitation: A Medium-term Situated Study of Motivational Aspects and Impact on Functional Reach

Exergames are increasingly considered as an exercise instruction modality in health applications. Studies are typically conducted in non-situated contexts and capture short-term effects. We present first results from a medium-scale study conducted over the course of 5 weeks and integrated into a normal rehabilitation program. The study features three groups, comparing manually adjustable exergames with the identical games in adaptive versions and manual physiotherapy interventions without games. The results indicate that the exergames and traditional therapy are comparable regarding measures of competence and enjoyment, while exergames led to significantly higher scores for autonomy, presence, and in a functional reach test. With traditional therapy, scores for tension-pressure and effort-importance were significantly higher. The initial results of the broader study presented in this paper deliver insights regarding motivational aspects of exergames and traditional therapy and point out which motivational aspects could be strengthened in future implementations.

Using Game Engines for Visualization in Scientific Applications

In recent years, the computer gaming industry has become a large and important market and impressive amounts of money are spent on the development of new game engines. In contrast to their development costs, the price for the final product is very low compared to a professional 3D visualization/animation program. The idea to use this potential for other purposes than gaming seems obvious. This work gives a review on three Serious Gamingprojects, analyzes the encountered problems in a greater context and reflects the pros and cons of using game engines for scientific applications in general.

A Tool for Landscape Architecture Based on Computer Game Technology

Modern computer game engines have reached a level of visual quality that makes them usable for other tasks and applications than mere entertainment. In this paper we will present our prototype of an interactive tool for landscape architecture based on the well-known CryENGINE and the game Farcry. We will present the steps necessary to automatically derive a valid Farcry level for real GIS data and show some preliminary results.

The influence of music on player performance in exergames for parkinson's patients

Music therapy and music and rhythm in general can support standard physiotherapy for people suffering from Parkinsons disease to improve the motion performance and quality, sometimes even helping to overcome motion blocks. With the availability of cheap motion-tracking devices, exergames have become an interesting option to complement traditional physiotherapy. However, the role of music and rhythm in the context of games for this special audience is still largely unexplored. Based on a prototype exergame we developed, a user study was conducted to compare the effects of different auditory clues and their absence in exergames for this target group. The results show significant performance differences with music versus without music, but surprisingly no differences were found between music synchronized with the interaction and unsynchronized background music.

A multi-touch system for 3D modelling and animation

3D modelling and animation software is typically operated via single-pointer input, imposing a serialised workflow that seems cumbersome in comparison to how humans manipulate objects in the real world. Research has brought forth new interaction techniques for modelling and animation that utilise input with more degrees of freedom or employ both hands to allow more parallel control, yet these are separate efforts across diverse input technologies and have not been applied to a usable system. We developed a 3D modelling and animation system for multi-touch interactive surfaces, as this technology offers parallel input with many degrees of freedom through one or both hands. It implements techniques for one-handed 3D navigation, 3D object manipulation, and time control. This includes mappings for layered or multi-track performance animation that allows the animation of different features across several passes or the modification of previously recorded motion. We show how these unimanual techniques can be combined for efficient bimanual control and propose techniques that specifically support the use of both hands for typical tasks in 3D editing. A study proved that even inexperienced users can successfully use our system for a more parallel and direct modelling or animation process.

Integrated rotation and translation for 3d manipulation on multi-touch interactive surfaces

In the domain of 2D graphical applications multi-touch input is already quite well understood and smoothly integrated translation and rotation of objects widely accepted as a standard interaction technique. However, in 3D VR, modeling, or animation applications, there are no such generally accepted interaction techniques for multi-touch displays featuring the same smooth and fluid interaction style. In this paper we present two novel techniques for integrated 6 degrees of freedom object manipulation on multi-touch displays. They are designed to transfer the smooth 2D interaction properties provided by multi-touch input to the 3D domain. One makes separation of rotation and translation easier, while the other strives for maximum integration of rotation and translation. We present a first user study showing that while both techniques can be used successfully for unimanual and bimanual integrated 3D rotation and translation, the more integrated technique is faster and easier to use.

Instrument-mounted displays for reducing cognitive load during surgical navigation

PurposeSurgical navigation systems rely on a monitor placed in the operating room to relay information. Optimal monitor placement can be challenging in crowded rooms, and it is often not possible to place the monitor directly beside the situs. The operator must split attention between the navigation system and the situs. We present an approach for needle-based interventions to provide navigational feedback directly on the instrument and close to the situs by mounting a small display onto the needle.MethodsBy mounting a small and lightweight smartwatch display directly onto the instrument, we are able to provide navigational guidance close to the situs and directly in the operator’s field of view, thereby reducing the need to switch the focus of view between the situs and the navigation system. We devise a specific variant of the established crosshair metaphor suitable for the very limited screen space. We conduct an empirical user study comparing our approach to using a monitor and a combination of both.ResultsResults from the empirical user study show significant benefits for cognitive load, user preference, and general usability for the instrument-mounted display, while achieving the same level of performance in terms of time and accuracy compared to using a monitor.ConclusionWe successfully demonstrate the feasibility of our approach and potential benefits. With ongoing technological advancements, instrument-mounted displays might complement standard monitor setups for surgical navigation in order to lower cognitive demands and for improved usability of such systems.

Virtual Reality for User-Centered Design and Evaluation of Touch-free Interaction Techniques for Navigating Medical Images in the Operating Room

Computer-assisted surgery has pervaded the operating room (OR). While display and imaging technologies advance rapidly, keyboard and mouse are still the dominant input devices, even though they cause sterility problems. We present an interactive virtual operating room (IVOR), intended as a tool to develop and study interaction methods for the OR, and two novel touch-free interaction techniques using hand and foot gestures. All was developed and evaluated with 20 surgeons. The results show that our techniques can be used with minimal learning time and no significant differences regarding completion time and usability compared to the control condition relying on verbal instruction of an assistant. Furthermore, IVOR as a tool was well received by the surgeons, although they had no prior experience with virtual reality. This confirms IVOR is an effective tool for user-centered design and evaluation, providing a portable, yet realistic substitution for a real OR for early evaluations.

Proxy-based selection for occluded and dynamic objects

We present a selection technique for 2D and 3D environments based on proxy objects designed to improve selection of occluded and dynamic objects. We explore the design space for proxies, of which we implemented the properties colour similarity and motion similarity and tested them in a user study. Our technique significantly increases selection precision but is slower than the reference selection technique, suggesting a mix of both to optimise speed versus error rate for real world applications.