It should be possible to calculate map position based on grid reference. The result can theoretically pinpoint position on the map with the accuracy of the grid square. Because of fault in grid reference calculation this is not possible.

Altis:

player setpos [4600,5600,0]
mapgridposition player; //"046056"

player setpos [4700,5700,0]
mapgridposition player; //"046056" <- should be "047057"

player setpos [4800,5800,0]
mapgridposition player; //"048058"

player setpos [4900,5900,0]
mapgridposition player; //"048058" <- should be "049059"

modified format on stratis:

offsetX = 0;
offsetY = 8192;
class Zoom1
{
zoomMax = 0.2;
format = "XY";
formatX = "Aaa";
formatY = "000";
stepX = 100;
stepY = -100;
};

player setpos [4400,5600,0];
mapgridposition player; //"Aee056"

player setpos [4500,5700,0];
mapgridposition player; //"Aee056" <- should be "Aef057"

player setpos [4600,5700,0];
mapgridposition player; //"Aeg056" <- should be "Aeg057"

player setpos [4700,5800,0];
mapgridposition player; //"Aeg058" <- should be "Aeh058"

etc.