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R. Preiner:
"Interactive Curved Reflections in Large Point Clouds";
Supervisor: M. Wimmer; Institut für Computergraphik und Algorithmen, 2010; final examination: 2010-05.

In the field of real-time rendering, computer graphics observes a continuously growing power of visualizing of scenes of continuously growing complexity. In the past few years, a number of rendering techniques have been developed that let the quality of the rendered images converge towards photorealism. Especially in the field of realistic scene illumination, Global Illumination (GI) techniques represent an important field of research. Previous to this work, for the first time we have applied a GI algorithm also to point clouds, which enables us to achieve realistic illumination of diffuse and glossy objects in real-time. This thesis elevates the power of visualization of this GI-Renderer to the next level. For the first time, it implements a realistic, physically based rendering of mirroring surfaces also for point clouds. Current real-time approaches addressing curved mirroring surfaces in polygon scenes either are extremely imprecise or cannot handle each arbitrary type of surface. Especially concave surfaces represent a significant difficulty for current physically based methods. Up to now, physically correct mirror reflections on complex surfaces can only be produced by offline algorithms. We introduce a novel rendering technique called "Screen-space curved reflections", which enables us to produce physically correct mirror reflections on arbitrarily complex surfaces. Our method bases on the approach, for each point in the scene to find the pixel in the framebuffer that contains its reflecting surface point. This is achieved by the application of a fast 2D root finding in a new error function called "mirror-space error function". Although our method raises high demands on the hardware, we are able to render common scenes at interactive frame rates.

http://publik.tuwien.ac.at/files/PubDat_188977.pdf