In a couple RPG settings (such as Pathfinder), line of sight is defined as coming from the corners of the character's square while every map program I've used draws line of sight from the center of the square. This comes up any time a player wants to peak around a corner and has to either move their token into an adjacent square or position themselves straddling the line. While not the biggest deal, it'd be a nice quality of life feature if it was calculated from all four corners or at the very least was an option. Edit Diagrams included to showcase actual vs. current behavior where P is the player and E are enemies where terribly drawn lines in MS Paint indicate line of sight.