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Ethan Alpert wrote:
<blockquote
cite="mid1FB6937A87F9074C9A2B8F9D9137EB1603A8CC96@COMAIL01.digitalglobe.com"
type="cite">
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<div><span class="451275519-28072005"><font color="#0000ff"
face="Arial" size="2">You should be using the units of the laea
projection rather than decimal degrees to set the EXTENT. </font></span></div>
<div><span class="451275519-28072005"></span> </div>
<div><span class="451275519-28072005"><font color="#0000ff"
face="Arial" size="2">It's very difficult to know from a lat/long box
what the output of the projection will be. It's best to use the units
of the projected coordinate system.</font></span></div>
<div><span class="451275519-28072005"></span> </div>
<div><span class="451275519-28072005"><font color="#0000ff"
face="Arial" size="2">-e</font></span> </div>
</blockquote>
Thanks. That worked.... For all the other newbies, and since this was
so confusing to me, I thought I would post the solution for people to
google later.<br>
<br>
My previous extent was in lat/lon<br>
EXTENT -85 32 -75 3<br>
<br>
Since I just wanted the North Carolina area, so I used the cs2cs
conversion program to convert from Lat Lon to Lambert Azimuthal Equal
Area Projection coordinates.<br>
<br>
C:\mapserver\data>cs2cs +proj=latlong +datum=WGS84 +to +proj=laea
+ellps=clrk66<br>
+lat_0=45 +lon_0=-100<br>
-85 32 <---type lower left coords here<br>
1417368.72 -1316195.76 0.000 <br>
-75 38 <--- type upper right coords here<br>
2159115.16 -450114.08 0.000<br>
<br>
New extent is <br>
EXTENT 1417368.72 -1316195.76 2159115.16 -450114.08<br>
<br>
# Projection (global, in Map object)<br>
PROJECTION<br>
# Projection parameters can be defined in two ways...<br>
# This is the traditional Proj.4 definition of Lambert Azimuthal
Equal-Area<br>
# projection for the Continental U.S.<br>
"proj=laea"<br>
"ellps=clrk66"<br>
"lat_0=45"<br>
"lon_0=-100"<br>
END<br>
<br>
# My tif layer:<br>
LAYER <br>
NAME elevation<br>
DATA "elevation/05539624.tif"<br>
TYPE RASTER<br>
STATUS ON<br>
END<br>
<br>
# Another layer with the a projection:<br>
<br>
LAYER<br>
NAME counties<br>
DATA "counties/co37_d00"<br>
TYPE POLYGON<br>
STATUS ON<br>
CLASSITEM "STATE"<br>
CLASS<br>
NAME counties<br>
EXPRESSION "37"<br>
STYLE <br>
COLOR -1 -1 -1<br>
OUTLINECOLOR 5 5 5<br>
END<br>
END<br>
PROJECTION<br>
"init=epsg:4326"<br>
END<br>
END<br>
<br>
<br>
--<br>
PHP Stuff:<br>
<a class="moz-txt-link-freetext" href="http://www.douglassdavis.com/">http://www.douglassdavis.com/</a><br>
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