I need to draw a map .I have the latitude longitude values of it .I was able to map these to screen coordinates and then draw the map.Once the map is drawn,as the mouse moves over the map i need to show the latitude and longitude values. This is where i am struck .For the initial case its simple,just rearrangement of window to view port mapping formula .i.e.,
u = (x-xmin)* sx+ umin
v = (y-ymin)* sy + vmin
But once the zoom and pan operations are applied on the map, I dont know how to get the latitude longitude values for each screen coordinate .
If some one knows how to solve this ,Please help me
Thanks in advance