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<p class=MsoNormal>Hello guys,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I just started to work a little with your map and wanted to
write a small test application to see it in action (I wanted to used it later
for easier map editing on OSM).<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Now I have a little problem. Your map is a rectangular with
the same width as height. So for the Longitude (width) it’s pretty easy
for me to convert the pixel-coordinates to actual geographical coordinates:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>(x/width)*360.0f-180.0f<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>This
gives me the coordinate of x (my mouse pointer on the map).<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>I
tried to do the same for the Latitude (height):<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>((y/height)*180.0f-90.0f)*-1.0f<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Well,
it doesn’t seem to give me the correct results. This is probably because
the earth is an ellipse and you display it as a rect. So the distance between
each degree Latitude decrease in your rectangular map, but I absolutely have no
idea of how to correctly calculate it.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>I’ve
spent some time searching and the best I’ve come up so far are these
formulars:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><a
href="http://en.wikipedia.org/wiki/Latitude#Common_.22latitude.22">http://en.wikipedia.org/wiki/Latitude#Common_.22latitude.22</a><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>But
there are so many of them and I don’t know which to use (if any of these
is even the right one). I tested some but nothing good came out of it </span><span
style='font-size:10.0pt;font-family:Wingdings'>L</span><span style='font-size:
10.0pt;font-family:"Courier New"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Please
guys, can someone put me in the right direction?<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Thank
you!<o:p></o:p></span></p>
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