Casting Shadows in Real Time

Shadows are crucial for enhancing realism and provide important visual cues. In recent years, many important contributions have been made both for hard shadows and soft shadows. Often spurred by the tremendous increase of computational power and capabilities of graphics hardware, much progress has been made concerning visual quality and speed, making high-quality real-time shadows a reachable goal. But with the growing wealth of available choices, it is particularly dicult to pick the right solution and assess shortcomings. Because currently there is no ultimate approach available, algorithms should be selected in accordance to the context in which shadows are produced. The possibilities range across a wide spectrum; from very approximate but really ecient to slower but accurate, adapted only to smaller or only to larger sources, addressing directional lights or positional lights, or involving GPU- or CPU-heavy computations. This course tries to serve as a guide to better understand limitations and failure cases, advantages and disadvantages, and suitability of the algorithms for dierent application scenarios. We will focus on real-time to interactive solutions but also discuss oine approaches if needed for a better understanding. In the future, we will provide you with more information via the course webpage: http://www.mpi-inf.mpg.de/resources/ShadowCourse/.

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