This paper will present the major findings of the author’s hovedfag (M.A.) thesis [1], which investigates how the player engages in the structuring of courses of action in computer games. Since the player’s engagement may be said to be a problem solving process, this paper presents a scheme of problem solving in modern computer games that proposes the concept of computer game agency. The scheme...

The floristic results are presented of a number of expeditions to the Aran Islands made during the years 1969-1976 by the author and by Professor Moore, Mr. White and other members of the Botany Department of University College, Dublin, and a few other helpers. They are critically compared with the results obtained by nineteenth-century explorers of the islands; the numerous discrepancies are a...

Rendering of shadows is a very important ingredient in three-dimensional graphics since they increase the level of realism and provide cues to spatial relationships. Area or volumetric light sources give rise to so called soft shadows, i.e., there is a smooth transition from no shadow to full shadow. For hard shadows, which are generated by point light sources, the transition is abrupt. Since a...

In the infrared spectrum, two contributions to shadows exist: one part are reflective shadows resulting from occlusion of instantly reflected infrared rays, and the other part are thermal shadows occurring through occlusion of irradiance in the past. The realization of thermal shadows requires a thermal balance calculation in 4D (3D geometry in 1D time) which is computational expensive, and the...

In a natural environment, cast shadows abound. Objects cast shadows both upon themselves and upon background surfaces. Previous research on the perception of 3-D shape from cast shadows has only examined the informativeness of shadows cast upon flat background surfaces. In outdoor environments, however, background surfaces often possess significant curvature (large rocks, trees, hills, etc.), a...

Rendering shadows quickly is an active area of computer graphics research. This dissertation improves the practicality of using a small number of point-sampled light sources to approximate soft shadows. Results are presented from two perceptual experiments demonstrating the perceptual efficacy of soft shadows as spatial cues for a specific set of tasks . A third experiment found coarse point-sa...