Jaroslav Krivánek is a visiting researcher at the Cornell University Program of Computer Graphics. Prior to this appointment, he worked as assistant professor at the Czech Technical University in Prague. He received his Ph.D. from IRISA/INRIA Rennes and Czech Technical University (joint degree) in 2005. In 2003 and 2004 he was a research associate at the University of Central Florida. He received a Masters in computer science from the Czech Technical University in Prague in 2001. Jaroslav’s research focuses mainly on realistic rendering and global illumination.Pascal Gautron is a R&D Engineer at Thomson Corporate Research France. In 2006 he received a Ph.D. in computer graphics from the University of Rennes 1, France, in collaboration with the University of Central Florida. He was a postdoctoral fellow at Orange Labs in 2007. His main research interest is high quality real-time rendering using graphics hardware, including global illumination and participating media.