i think mix is a method of the class CSB.  it's not so much referencing itself as referencing it's constructor, init.   and all the constructor does, really, is make an assign an object with the main properties we need to reference to define a surface (as stated above).  so it's basically saying:  class CSB takes an object and defines it's color, shine and bump properties.  the CSB mix method lets you assign a mix of colors to an item's color, a mix of shines to an object's shine, and a mix of bumps to an object's bump.  so if you keep creating CSB instances, you can keep mixing mixes.

bb- that is so cool!  so pardon, but why does that work?