<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0cm;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";
mso-fareast-language:EN-AU;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I have not used org2ogr. I have just realised that the C API for GDAL uses a mixture of STD and CDECL. How annoying. Anyway – I have carefully checked and all are correct. I get a stack balance problem if they are not anyway. It’s hard to see how I could get the arguments wrong – one is the string “WGS84”, and the other is an integer.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I still don’t know whether proj.dll is required.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Chaitanya kumar CH chaitanya.ch-at-gmail.com |GDAL| [mailto:5rm5yuc82t@sneakemail.com] <br><b>Sent:</b> Wednesday, October 19, 2011 6:36 PM<br><b>To:</b> marc.hillman@tpg.com.au; dev4cx4m9z@snkmail.com<br><b>Cc:</b> gdal-dev@lists.osgeo.org<br><b>Subject:</b> Re: [gdal-dev] Confused about datum transformations<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>Marc,<br><br>You don't need to rebuild proj.4; you are already using it.. Since you were able to use ogr2ogr to do the transformation, it works.<br><br>What you need to do is find out if the arguments you are passing to the transformation builder are good. Especially 'MapSRS'. If it doesn't show any problem, plug some debug messages in the OSR code in ogrct.cpp and rebuild gdal.<o:p></o:p></p><div><p class=MsoNormal>On Wed, Oct 19, 2011 at 12:46 PM, <<a href="mailto:dev4cx4m9z@snkmail.com">dev4cx4m9z@snkmail.com</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>Thanks for all the suggestions – they have given me many possibilities to eliminate, but I still haven’t really got an answer to the original question.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;color:#1F497D'>Am I required to have proj.dll built with support for the datums/projections I want to use, or is it sufficient to set GDAL_DATA such that gcs.csv and pcs.csv are visible? I’m working in <a href="http://VB.NET" target="_blank">VB.NET</a>, and I’m not confident I can rebuild PROJ with the required datums, so I wish to avoid if possible. I’d even be prepared to use SetGeogCS explicitly as I only use a few datums. If I use SetGeogCS, I can’t see what purpose proj.dll serves.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;color:#1F497D'>I have set GDAL_DATA to the correct folder.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;color:#1F497D'>I have checked that the datum numbers I use are in the gcs.csv file.</span><o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'> </span><o:p></o:p></p><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0cm 0cm 0cm;border-color:-moz-use-text-color -moz-use-text-color'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:10.0pt'>From:</span></b><span lang=EN-US style='font-size:10.0pt'> <a href="mailto:gdal-dev-bounces@lists.osgeo.org" target="_blank">gdal-dev-bounces@lists.osgeo.org</a> [mailto:<a href="mailto:gdal-dev-bounces@lists.osgeo..org" target="_blank">gdal-dev-bounces@lists.osgeo.org</a>] <b>On Behalf Of </b><a href="mailto:dev4cx4m9z@snkmail.com" target="_blank">dev4cx4m9z@snkmail.com</a><br><b>Sent:</b> Tuesday, October 18, 2011 4:12 AM<br><b>To:</b> <a href="mailto:gdal-dev@lists.osgeo.org" target="_blank">gdal-dev@lists.osgeo.org</a><br><b>Subject:</b> RE: [gdal-dev] Confused about datum transformations</span><o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I’m not sure the code will help too much, but here are the relevant code fragments. I’m using a hand crafted VB.net wrapper which explains some of the syntax<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Private WGS84SRS As New OGRSpatialReference ' Coordinate system in WGS84<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Private MapSRS As OGRSpatialReference ' Coordinate system of map<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Private ctWGS84toMap As OGRCoordinateTransformation ' Coordinate transform from WGS84 to map<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>With WGS84SRS<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> GDALError = .SetProjCS("WGS84 Datum")<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> Debug.Assert(GDALError = OGRError.OGRERR_NONE, GetLastErrorMsg())<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> GDALError = .SetWellKnownGeogCS("WGS84") ' Define WGS84 coordinate system<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> Debug.Assert(GDALError = OGRError.OGRERR_NONE, GetLastErrorMsg())<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>End With<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>With MapSRS<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> GDALError = .SetProjCS("Map coordinate system")<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> Debug.Assert(GDALError = OGRError.OGRERR_NONE, GetLastErrorMsg())<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> GDALError = .ImportFromEPSG(3577)<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> Debug.Assert(GDALError = OGRError.OGRERR_NONE, GetLastErrorMsg())<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>End With<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>ctWGS84toMap = GDAL.CreateCoordinateTransformation(WGS84SRS, MapSRS) ' Create a coordinate transformation - WGS84 to map<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Debug.Assert(ctWGS84toMap IsNot Nothing, GetLastErrorMsg())<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>Marc,<br><br>Can you provide the code leading to the error?<o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Tue, Oct 18, 2011 at 1:21 PM, Marc Hillman <<a href="mailto:dev4cx4m9z@snkmail.com" target="_blank">dev4cx4m9z@snkmail.com</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I have a GIS database, and all data is stored in WGS84 datum. I have developed an application using GDAL, and I now need to translate my WGS84 coordinates to several different datums, depending what map is loaded. I seem to be going around in circles, and need a nudge in the right direction. I am defining an OGRSpatialReference for each datum (WGS84 and current map) and then attempting to create an OGRCoordinateTransformation for the transformation.. This last step fails with a PROJ.4 error (“No PROJ.4 translation for destination SRS, coordinate transformation initialization failed”<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>My question is - Do I need PROJ.4 to do the translation? Can I not just use ImportFromWKT to define my OGRSpatialReference? If so, is there a nice canned list of all the WKT somewhere? I’m keen to avoid PROJ.4 if possible as I’m not sure I can build it.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><br>_______________________________________________<br>gdal-dev mailing list<br><a href="mailto:gdal-dev@lists.osgeo.org" target="_blank">gdal-dev@lists.osgeo.org</a><br><a href="http://lists.osgeo.org/mailman/listinfo/gdal-dev" target="_blank">http://lists.osgeo.org/mailman/listinfo/gdal-dev</a><o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><br><br clear=all><br>-- <br>Best regards,<br>Chaitanya kumar CH.<br><br><a href="tel:%2B91-9494447584" target="_blank">+91-9494447584</a><br>17.2416N 80.1426E<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com" target="_blank">www.avg.com</a><br>Version: 2012.0.1831 / Virus Database: 2092/4558 - Release Date: 10/17/11<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US><br>This email message is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply email and delete the original message. </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com" target="_blank">www.avg.com</a><br>Version: 2012.0.1831 / Virus Database: 2092/4558 - Release Date: 10/17/11<o:p></o:p></p></div></div></div></div><p class=MsoNormal><br>_______________________________________________<br>gdal-dev mailing list<br><a href="mailto:gdal-dev@lists.osgeo.org">gdal-dev@lists.osgeo.org</a><br><a href="http://lists.osgeo.org/mailman/listinfo/gdal-dev" target="_blank">http://lists.osgeo.org/mailman/listinfo/gdal-dev</a><o:p></o:p></p></div><p class=MsoNormal><br><br clear=all><br>-- <br>Best regards,<br>Chaitanya kumar CH.<br><br>+91-9494447584<br>17.2416N 80.1426E<br><br><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com">www.avg.com</a><br>Version: 2012.0.1831 / Virus Database: 2092/4560 - Release Date: 10/18/11<o:p></o:p></p></div></body></html>