Hi Michal<br><br><div class="gmail_quote"><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
But I have no idea how to create and install gtx file with geoid data?<br></blockquote><div><br>the gtx file description could be found on vdatum noaa pages : <br>
<a href="http://vdatum.noaa.gov/dev/gtx_info.html#dev_gtx_binary">http://vdatum.noaa.gov/dev/gtx_info.html#dev_gtx_binary</a><br><br>
some Vertical Datum could be found on <a href="http://download.osgeo.org/proj/vdatum/">http://download.osgeo.org/proj/vdatum/</a>
<br>You need to install them on the same directory as your proj nad file (
directory containing nadgrid data, EPSG dictionnary etc..). <br>Look at your
PROJ_LIB environnement Variable for the path of this directory.<br> <br></div><blockquote class="gmail_quote" style="margin:0pt 0pt 0pt 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Is there something like geo2bin? To compile text data in binary format?<br>
<br></blockquote><div><br>I'm not aware of such utilities, for french geoidgrids I have to write my own utilitiy to convert from french geoid format to gtx format (you could look this code on gitorious <a href="http://gitorious.org/proj4-sandbox/proj4-cmake/blobs/ign/proj/src/ign2gtx.c">http://gitorious.org/proj4-sandbox/proj4-cmake/blobs/ign/proj/src/ign2gtx.c</a> )<br>
<br>When your write "text data" do you mean like *.lla file ?<br><br> <br></div><blockquote class="gmail_quote" style="margin:0pt 0pt 0pt 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
How to aware proj that new gtx file exists and where?<br>
<br></blockquote><div> </div><div>A) add theses gtx files on your nad directory ( PROJ_LIB envVar)<br>B) add the "+geoidgrids" option on your proj description<br><br><br>Nicolas DAVID<br></div></div>