Particle-based Rendering for Porous Media.. Proceedings of The Annual SIGRAD Conference, Linköping University Electronic Press, 2010. [PUMA: 2010 sfb716-b3 sfb716-d3 vis(us) vis-ertl vis-gis visus visus:ertl visus:grottel visus:hilferrf visus:reina visus:zaunerts]