Distributed rendering of interactive soft shadows

ABSTRACT

Recently several distributed rendering systems have been developed which exploit a cluster of commodity computers by connecting host graphics cards over a fast network to form a compositing pipeline. This paper introduces a new algorithm which takes advantage of the programmable compositing operators in these systems to improve the performance of rendering multiple shadow-maps, for example to produce approximate soft shadows. With an nVidia GeForce4 Ti graphics card the new algorithm reduces the number of required render nodes by nearly a factor of four compared with a naive approach. We show results that yield interactive-speed rendering of 32 shadows on a 9-node Sepia2a distributed rendering cluster.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism