I was asked if Mantra or karma has the possibility of Rendering Double Refraction Material.
Because my shader knowledge is just in the base level it would be nice if somebody has some advice's, tips.
i add some links that i have found about Birefringency.
Wiki
https://en.wikipedia.org/wiki/Birefringence [en.wikipedia.org]
Technical Papers
https://www.cg.tuwien.ac.at/research/publications/2008/weidlich_2007_rrbuc/weidlich_2007_rrbuc-paper.pdf [www.cg.tuwien.ac.at]
http://www.ijfcc.org/papers/150-K00012.pdf [www.ijfcc.org]
Research Render
https://cgg.mff.cuni.cz/ART/about/ [cgg.mff.cuni.cz]