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<DIV>Hi Girish,</DIV>
<DIV> I would really welcome the addition of dual scattering. For
now the scheme that I settled on for the shader is the one proposed by Sadeghi
et al (2010), with the R,TT and TRT components being calculated using
approximations given by J. Ou et al (`ISHair: Importance Sampling for Hair
Scattering’). Sadeghi et al explicitly mention dual scattering in regards to the
diffuse component and give some details on the implementation, that you may find
interesting. I decided on this over other physically accurate models since it
does not require pre-computation and is quite artist friendly. More advanced
models can definitely be added later though.</DIV>
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<DIV>Stuart</DIV></DIV></DIV></BODY></HTML>