<div dir="ltr">Thanks, Brent and Paul for your suggestions.<div><br></div><div>I just tried gdal_polygonize.py and the result looks OK, but the lines are very jagged.</div><div><br></div><div>I also tried gdal_contour and it has the option to create polygons. And that result is looking better.</div><div>And gdal_contour is also easier to call from a C# application that a Python script ;)</div><div><br></div><div>I need to investigate further but I'll use gdal_contour.<br clear="all"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><br></div><div dir="ltr">Thanks,<br>
<br>Paul</div></div></div></div></div></div></div></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Op ma 10 apr 2023 om 23:10 schreef Brent Wood <<a href="mailto:pcreso@yahoo.com">pcreso@yahoo.com</a>>:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div style="font-family:verdana,helvetica,sans-serif;font-size:16px"><div>
<div dir="ltr">I have done this with QGIS, if you have a grid with categorised values, QGIS can generate a polygon shapefile with the cell boundaries merged by cell value.</div><div dir="ltr"><br></div><div dir="ltr">QGIS uses gdal_polygonize.py under the hood to do this (via a simple GUI interface), so if you work out the command line parameters you need, you could run it from the command line.<span></span><div><br></div></div><div><br></div><div dir="ltr">HTH,</div><div dir="ltr"><br></div><div dir="ltr">Brent Wood<br></div><div><br></div><div><br></div><div><div id="m_-5798385960369351636ydp6fd40e7byiv0881113880yqt89560"><div dir="ltr">On Fri, 7 Apr 2023 at 10:34, Paul Meems <<a shape="rect" href="mailto:bontepaarden@gmail.com" rel="nofollow" target="_blank">bontepaarden@gmail.com</a>> wrote:<br clear="none"></div><blockquote style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>Hello List,</div>I'm working on a C# application that uses Golden Software Surfer to create maps, but I also need to export the data to a polygon shapefile. <div>Unfortunately, Surfer creates a shapefile with shapes on top of each other instead of inside each other, and Golden Software support couldn't help with this issue. </div><div><br clear="none"></div><div>I have a grid-file in Surfer Bin Grid format that can be converted to other raster formats, a border shapefile created using ST_Convexhull, and a text file indicating the values of the polygons. </div><div><br clear="none"></div><div><img src="cid:1876fcb253dcb971f161" alt="image.png" style="width: 480px; max-width: 560px;"><br clear="none"></div><div><br clear="none"></div><div>Can anyone recommend a way to use GDAL/OGR to make a polygon shapefile from these resources, or suggest an alternative approach?<div><br clear="none"></div><div>Regards,</div><div><div><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr">
<br clear="none">Paul<br clear="none"><br clear="none"></div></div></div></div></div></div></div></div></div></div></div>
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