看一下幫助,裡面有 U,ELqi \
INTERFACE r [ t m m'] ? vK'9{q|g
COAT k coat coat' |0DP}
`~
-k !G>(j
+k WhenwQT
The signs in front of k can be used to instruct ASAP to either propagate only a reflected ray (-k: t=0) at that object or to propagate only a transmitted ray (+k: r=0) at that object. Ps |QW
+ 指只有折射沒有反射光, g`{Dxb,t
- 指只有反射沒有折射。