斑主用的是哪個(gè)版本的ＴＰ啊？４..０以前版本的manual有沒mentioned？

Solution: DB`$Ru@  
The plastic material with the rough diffusing surface can be modeled in [0u.}c;(  
TracePro, but as two separate properties (select Define/EditPropertyData). m_m8c8{
Y  
rFmKmV  
MATERIAL PROPERTY %j'G.*TD  
A TracePro Material Property can be created, and the index of refraction of =#i4MXRZ{  
the material is entered here, as well as an absorption coefficient if it is X,TTM,1w  
known (this would be for absorption losses just from propogating through a =.36y9Mfo  
given thickness of a clear polished sample of the material, unrelated to the kmlG3hOR,  
diffusing surface finish.  Entering zero for the absorption coefficient is ]C16y. ~e  
propobly a reasonable estimate for a transparent material. .tRr?*V|l  
YlswSQ  
The Material Property is applied to the Object (Define/Apply Properties). <0u\dU  
/m`}f]u  
SURFACE PROPERTY d4Co^A&  
A TracePro Surface Property can specify 5 possible outcomes for light incident +yf(Rs)!  
on a surface - Specular Transmission, Specular Reflection, Scattered *Y85DEA  
Transmission (BTDF). Scattered Reflection (BRDF), and Absorption. ic*->-!  
~+O