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<p class=MsoNormal>Good day!<o:p></o:p></p>
<p class=MsoNormal>I am trying to set the Projection Definition for a
GDALDataset as follows (from the GDALWarp API):<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>const
char *pszDstWKT = NULL;<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>OGRSpatialReference
oSRS;<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>oSRS.SetUTM(
11, TRUE );<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>oSRS.SetWellKnownGeogCS(
"WGS84" );<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>oSRS.exportToWkt(
&pszDstWKT );<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>if(GDALSetProjection(srcDataset,
pszDstWKT) == CE_Failure)<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>{
//handle failure<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>{else<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>{<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> const
char *defString = srcDataset->GetProjectionRef();<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> cout<<”Length:
“<<strlen(defString)<<endl;<o:p></o:p></span></i></p>
<p class=MsoNormal style='text-indent:.5in'><i><span style='font-size:10.0pt;
font-family:"Arial","sans-serif"'>cout<<”Projection: ”<<defString<<endl;<o:p></o:p></span></i></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>};<o:p></o:p></span></i></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Firstly, I get a compiler error with the oSRS.exportToWKT
statement:<br>
invalid conversion from ‘const char**’ to ‘char**’. <o:p></o:p></p>
<p class=MsoNormal><span style='font-family:Wingdings'>à</span> So I changed
the const char* to char*, which bypassed that little error.<o:p></o:p></p>
<p class=MsoNormal><span style='font-family:Wingdings'>à</span> As this was
used exactly as the GDALWarp API Tutorial describes, why does this happen?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Secondly, After the GDALSetProjection(…) call
succeeds, the projection information is supposed to be printed out to standard
out, along with the length of the definition string.<br>
However, the output is as follows:<br>
$ Length: 0<o:p></o:p></p>
<p class=MsoNormal> $ Projection: <o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>Why is the projection string still empty? <o:p></o:p></p>
<p class=MsoNormal>I know that the pszDstWKT contains the projection
information as set up, since when printed out to screen it’s displayed
correctly.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thank you in advance!!<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-family:"Lucida Calligraphy"'>Warm Regards<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Lucida Calligraphy"'>Francois
Maass<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Lucida Calligraphy"'>B.IT<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Lucida Calligraphy"'>University of
Pretoria<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Lucida Calligraphy"'>Cell: 072 397
0294<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Lucida Calligraphy"'>Email:
fieliesm@gmail.com<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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