JackFlexibleDoubleSide Shader

     This is a double side shader which can be pluged to assign
separate side (front and back face).

     This shader can be pluged with every nodes provided from the button back of

each parameter that's why its name like that (hope it's not too long)

,actually my co-worker named it for me(first, its name is JackDS ^^).

     And, it has 'Swap' parameter to be used for swaping or checking looks.

     It need to connect to other shaders before attach to objects.

     Works fine on renderMan 6.5 (latest version).

     Any comments or suggestions feel free to mail me : jacksaran@hotmail.com

     Thank you.