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<p class="MsoNormal">Hi<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I was just trying to parallelize buffering of a large set of polygons using GDAL 2.1 in C#.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">My code is something like the following:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white">List<Geometry> polygonList =
</span><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New"">List of polygons…</span><span lang="EN-US" style="font-family:"Courier New""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white">var result = new ConcurrentBag<Geometry>();</span><span lang="EN-US" style="font-family:"Courier New""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white">Parallel.ForEach(polygonList, polygon =><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white">{<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white"> var polygonBuffer = polygon.Buffer(1, 1);<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white"> result.Add(polygonBuffer);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:9.5pt;font-family:"Courier New";background:white;mso-highlight:white">});</span><span lang="EN-US" style="font-family:"Courier New""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I get a System.AccessViolationException in ogr_csharp.dll on the Buffer(…) line. Since my method runs fine using a normal foreach or if I omit the Buffer(…) method, I assume it has something to do with thread safety and
OGR.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">So is my problem just that OGR Buffer(…) isn’t thread safe or am I doing something wrong here?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Regards, Casper<o:p></o:p></span></p>
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