I have GoogleMaps-object. Also I have SouthWest and NorthEast point in GLatLng-format. Also I have (x,y) of cursor over my object. I want know GLatLng under cursor without use map.onMouseMove (only use DOM-onMouveMove). I try write JavaScript-code:
var w = map.getSize().width;
var h = map.getSize().height;
var left = map.getBounds().getSouthWest().lat();
var right = map.getBounds().getNorthEast().lat();
var top = map.getBounds().getSouthWest().lng();
var bottom = map.getBounds().getNorthEast().lng();
var x = e.pageX - map_canvas.offsetLeft;
var y = e.pageY - map_canvas.offsetTop;
var lng = top + (bottom - top) * x * 1.0 / w;
var lat = left + (right - left) * (h - y) * 1.0 / h;
But in this way I do not have enough accuracy. What is the normal transformation formulas in the geographic coordinates of the screen?