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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi Guys,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’ve been studying the tile generation code for ka-map
and as I’m not used GIS type calculations am having some trouble with
understanding some of the maths regarding scale etc, in the kaMap zoomToExtents
method, especially the following line and its significance: this.cellSize =
newScale/(oMap.resolution * inchesPerUnit[oMap.units]);, which translates in my
case to scale/(72*39.3701).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>For example if I had the following 529.166 = 1500000/(2834.6472)
with the first part being my scale and the second part being how many pixels
there are in a meter, what is the significance of 529.166?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The cellsize variable is then used in the later equations
and methods to ultimately produce the tiles in tile.php without having to pass
a geo extent for each image to tile.php, I have been modifying the system and
it works but I would like to understand how it is working, if anyone has any
insight for someone who should have paid more attention to his maths teacher at
school, it would be most appreciated.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Chris </span></font><o:p></o:p></p>
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