The apron of the sheet is what separates adjacent sheets, and in this context provides a border around the outside of the sheet
curling_sheet_apron(
sheet_length = 0,
sheet_width = 0,
apron_behind_back = 0,
apron_along_side = 0
)
A data frame containing the bounding coordinates of the sheet's apron
The length of the sheet, from back board to back board
The width of the curling sheet, from side wall to side wall
The extension of the apron beyond the back board
The extension of the apron running along the side walls