First off, this looks amazing.

Sorry if this is a stupid question, but what does this mean: "Speck renders atoms and bonds not with polygons, but with imposters. This means you can zoom in as close as you like and surfaces remain smooth, not faceted."

I've only ever heard of imposters as bitmaps or simpler models, replacing the original 3d models at a distance. But I guess this is something entirely different... Could you point me in the right direction on this topic?