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<DIV><FONT face=Arial size=2>Hi list,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>If the next question is a stupid one, excuse me. I
am newbe.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>context:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I use mapserv CGI (no mapscript) and a Apache
webserver with PHP (on a windows machine for testing). I am building a
web-application with dynamic maps. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>problem:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I use a template file to get information about the
map-features on the current map. The tags [shpmidx] and [shpmidy] provides
information on the exact position of a feature (see <A
href="http://mapserver.gis.umn.edu/doc36/template-reference.html">http://mapserver.gis.umn.edu/doc36/template-reference.html</A> ).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>With simple lineair algebra it is possible to
calculate the xy-position of this feature on the actual generated image.
(a lineair transformation from "real world" lat-lon coordinates to "image"
x-y pixelcoordinates).</FONT></DIV>
<DIV><FONT face=Arial size=2>I use these information to create some kind of
javascript rollover interface; if the mouse hovers a feature, the webapplication
respons immediately, without the need of connecting to the server.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So far so good. Everything works fine. So now for
the problem. If I deploy a projection ("proj=stere") Nothing works
anymore. That is because [shpmidx] and [shpmidy] gives the lon-lat stuff, but i
need the xy coordanates on the generated image of the map. Sure it should be
possible to write transformations for projected maps (a lot of sinus and
cosinus, arctangens etcetera i suppose) but i believe that's a ticket to the
nearest snake pit.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Is there a solution for this (withhout the need of
writing my own transformation formulas)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Or, if I have to write transformation, does anybody
now the formulas for this projection:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2><FONT size=2>
<P>PROJECTION</P>
<P>"proj=stere"</P>
<P>"lat_0=52.156160556"</P>
<P>"lon_0=5.387638889"</P>
<P>"k=0.0000999908"</P>
<P>"x_0=0.000"</P>
<P>"y_0=0.000"</P>
<P>"ellps=bessel"</P>
<P>END</P></FONT></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Cheers,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Marco</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Marco Pieck, <A
href="mailto:marco@mediaeval.nl">marco@mediaeval.nl</A><BR>Mediaeval Vorm &
Visie<BR><A
href="http://www.mediaeval.nl/">http://www.mediaeval.nl/</A><BR>postbus 1050,
6501 BB Nijmegen, the Netherlands <BR>tel: ++ 31 24-3818196, fax: ++
31 24-3818183<BR></DIV></FONT></BODY></HTML>