Shadow Algorithms for Real-time Rendering

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 difficult 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 efficient to slower but accurate, adapted only to smaller or only to larger sources, addressing directional lights or positional lights, or involving GPUor CPU-heavy computations. This tutorial tries to serve as a guide to better understand limitations and failure cases, advantages and disadvantages, and suitability of the algorithms for different application scenarios. We will focus on real-time to interactive solutions but also discuss offline approaches if needed for a better understanding. In the future, we will provide you with more information via our webpage: http://www.mpi-inf.mpg.de/resources/ShadowCourse/.