A sheet is represented by a two-dimensional matrix of squares, each square containing an
item to visually display the sheet (a square of 32x32 graphic pixels), five logic switches and three integer values (two having a range from 0 till 1023, one having a range from 0 till 127). See also
sheet editing.
In the main function the
main sheet is predefined, which is displayed in the program window as an
item layer. It is the main sheet that determines the program window size. By setting an item into the main sheet this item is displayed in the window.