Finally, I use the solution of changing the PROJ_LIB environment variable when my VB program start. I can now call the projection function (pjTransform) but the result are bad. I have a gap of about 100 meters between the real position and the projected coordinates.
<br>My aim is to project WGS 84 coordinates from garmin GPS to various european state coordinates. This is my first attempt to use proj4 and I don't know what I do wrong.<br>Here is the definition I use :<br>WGS 84 (epsg : 4326) : +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs <>
<br>Lambert 72 Belge (epsg : 31370) : +proj=lcc +lat_1=51.16666723333333 +lat_2=49.8333339 +lat_0=90 +lon_0=4.367486666666666 +x_0=150000.013 +y_0=5400088.438 +ellps=intl +units=m +no_defs no_defs <><br><br>Someone can help me ?
<br><br><div><span class="gmail_quote">2006/8/1, Eric Miller <<a href="mailto:EMiller@dfg.ca.gov">EMiller@dfg.ca.gov</a>>:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
That VB wrapper hasn't been updated to know about the<br>pj_set_searchpath() function. I'm not sure if the pj_set_finder()<br>function will work. You could try it. See the AddressOf operator. I<br>seem to recall it doesn't work due to calling convention issues.
<br><br>If you can figure out how to change the PROJ_LIB environment variable<br>from within your VB program, that should work. Just do it during<br>program startup before any proj.4 functions are called. Or, maybe, use a
<br>batch file that launches your VB program and sets the PROJ_LIB<br>variable?<br><br>>>> <a href="mailto:gheysen.t@gmail.com">gheysen.t@gmail.com</a> 8/1/2006 1:19:04 AM >>><br>Hello,<br><br>I have wrote a little program in vb to download and upload GPS data.
<br>This<br>software use 2 specific functions to transform the data from WGS 84 to<br>Lambert 72 (Belgium) and from Lambert 72 to WGS 84. I want to replace<br>these<br>functions by the proj.4 vb wrapper so I can use this software in other
<br>contry than Belgium. I have test, without problem, this wrapper with<br>the<br>file "exemple.mdb".<br><br>My problem is that I have Qgis installed and thus I have already a<br>"Proj_lib" environment variable. If user uninstall Qgis, the
proj.4 is<br>uninstall. How can I have two versions of Proj.4 install on the same<br>computer. I have read than I can use pj_set_finder() or<br>pj_set_searchpath()<br>to override this environment variable. This function is it available
<br>through<br>the vb wrapper ? If yes, how can I use this in vb ?<br><br>Thanks in advance.<br><br>Gheysen Thibaut.<br>_______________________________________________<br>Proj mailing list<br><a href="mailto:Proj@lists.maptools.org">
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