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<p class="MsoNormal">OK, with the help of your GDALGetRasterCount() hint I fixed it. The problem was that before
<a href="https://github.com/OSGeo/gdal/pull/12124">#12124</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Gdal.OGRGetDriverByName(Gdal.shortname(getdriver(dataset))) returned NULL for raster types, but from #12124 on it returns a non-NULL pointer, and the code flow went to wrong branches.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Uff, that tricky. Thanks<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">From:</span></b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none"> Joaquim Manuel Freire Luís <jluis@ualg.pt>
<br>
<b>Sent:</b> Monday, May 12, 2025 12:39 AM<br>
<b>To:</b> Joaquim Manuel Freire Luís <jluis@ualg.pt>; Even Rouault <even.rouault@spatialys.com>; gdal-dev <gdal-dev@lists.osgeo.org><br>
<b>Subject:</b> RE: [gdal-dev] GDAL 3.11 broke part of the Julia wrapper<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Sorry, forgot to pass the pointer. Also here it says the layer count is zero<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">ccall((:GDALDatasetGetLayerCount, libgdal), Cint, (Ptr{Cvoid},), ds.ptr)<o:p></o:p></p>
<p class="MsoNormal">0<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">From:</span></b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none"> gdal-dev <</span><a href="mailto:gdal-dev-bounces@lists.osgeo.org"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">gdal-dev-bounces@lists.osgeo.org</span></a><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">>
<b>On Behalf Of </b>Joaquim Manuel Freire Luís via gdal-dev<br>
<b>Sent:</b> Monday, May 12, 2025 12:34 AM<br>
<b>To:</b> Even Rouault <</span><a href="mailto:even.rouault@spatialys.com"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">even.rouault@spatialys.com</span></a><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">>; gdal-dev
<</span><a href="mailto:gdal-dev@lists.osgeo.org"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">gdal-dev@lists.osgeo.org</span></a><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">><br>
<b>Subject:</b> Re: [gdal-dev] GDAL 3.11 broke part of the Julia wrapper<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Right. But I do that I get another error that I’m not sure how to interpret. It comes from some Julia internal<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">ccall((:GDALGetRasterCount, libgdal), Cint, (Ptr{Cvoid},), ds)<o:p></o:p></p>
<p class="MsoNormal">Internal Error: MethodError: no method matching unsafe_convert(::Type{Ptr{Nothing}}, ::GMT.Gdal.IDataset)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">From:</span></b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none"> Even Rouault <</span><a href="mailto:even.rouault@spatialys.com"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">even.rouault@spatialys.com</span></a><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">>
<br>
<b>Sent:</b> Monday, May 12, 2025 12:15 AM<br>
<b>To:</b> Joaquim Manuel Freire Luís <</span><a href="mailto:jluis@ualg.pt"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">jluis@ualg.pt</span></a><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">>; gdal-dev <</span><a href="mailto:gdal-dev@lists.osgeo.org"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">gdal-dev@lists.osgeo.org</span></a><span style="font-family:"Calibri",sans-serif;mso-ligatures:none">><br>
<b>Subject:</b> Re: [gdal-dev] GDAL 3.11 broke part of the Julia wrapper<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p><o:p> </o:p></p>
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<p class="MsoNormal"><span lang="PT">Le 12/05/2025 à 01:04, Joaquim Manuel Freire Luís via gdal-dev a écrit :<o:p></o:p></span></p>
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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">I’m afraid this one is not going to be easy, and I don’t know how much help I can provide to find the issue. The think is that
<a href="https://github.com/OSGeo/gdal/pull/12124">https://github.com/OSGeo/gdal/pull/12124</a> (which is a very big PR) broke my Julia wrapper.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">For example, this used to write a png image but now it errors with<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">julia> gdalwrite("lixo.png", mat2img(UInt8.([1 2 3; 4 5 6; 7 8 9])))<o:p></o:p></p>
<p class="MsoNormal">ERROR 1: Cannot guess driver for lixo.png<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">But maybe more concrete is this failure where it tries to extract info from a gdal dataset (a pointer )<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><br>
Gdal.GDALGetRasterYSize(dataset.ptr)<o:p></o:p></p>
<p class="MsoNormal">49<o:p></o:p></p>
<p class="MsoNormal">Gdal.GDALGetRasterCount(dataset.ptr)<o:p></o:p></p>
<p class="MsoNormal">1<o:p></o:p></p>
<p class="MsoNormal">Gdal.GDALDatasetGetLayerCount(dataset.ptr)<o:p></o:p></p>
<p class="MsoNormal">0<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Here, first two are correct be the third is now wrong.<o:p></o:p></p>
</blockquote>
<p>Why is GDALDatasetGetLayerCount() == 0 wrong on a raster dataset ? It looks like the expected result<o:p></o:p></p>
<p>If I'm looking at the correct source code <a href="https://github.com/GenericMappingTools/GMT.jl/blob/94649db2b48d3223c8b8628b6fac4d3df60b8938/src/gdal_utils.jl#L859">
https://github.com/GenericMappingTools/GMT.jl/blob/94649db2b48d3223c8b8628b6fac4d3df60b8938/src/gdal_utils.jl#L859</a> , then this line is fragile. Rather than testing if OGRGetDriverByName() returns a non null pointer to guess if that dataset is raster or
vector, you could indeed test GDALGetRasterCount() != 0 to infer this is a raster dataset.<o:p></o:p></p>
<pre>-- <o:p></o:p></pre>
<pre><a href="http://www.spatialys.com">http://www.spatialys.com</a><o:p></o:p></pre>
<pre>My software is free, but my time generally not.<o:p></o:p></pre>
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