I am not exactly sure what you mean, but here are a few old, fuzzy photos of dual 1992 built shelves in a 14x32 x 18' high room[dismantled in 2008]? The lower shelf has two tracks and the upper three. At this height it is best to "stair-step" the tracks up for line of sight from the floor, especially for little folks.
Although this operation eventually had scenicked corners and building fronts/murals along the walls it was basically a "run and display" layout for long trains. The glassed end wall was round with 0156 curves.