Math problem

[Ofnuts]

(05-04-2023, 12:27 PM)rich2005 Wrote: I do not understand that. As the window moves what is subtraced off one side is added to the other side so sum total space is constant.

That's also what I thought, but this is only true if the window is an integer multiple of the cell. Otherwise depending on offset you can have a varying total number of grid lines across the window:

   

(illustration of numbers above, scaled 20x)