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<pre><span lang="EN-US" style="color:#1F497D">Hello<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></pre>
<pre><span lang="EN-US" style="color:#1F497D">I want to implement a vector mbtile viewer and am considering using gdal to extract the data.<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="color:#1F497D">I am wondering if gdal public API allows to :<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></pre>
<pre style="margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span lang="EN-US" style="color:#1F497D"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">   </span></span></span><![endif]><span lang="EN-US" style="color:#1F497D">Retrieve metadata such as :<o:p></o:p></span></pre>
<pre style="margin-left:72.0pt;text-indent:-18.0pt;mso-list:l0 level2 lfo2"><![if !supportLists]><span lang="EN-US" style="color:#1F497D"><span style="mso-list:Ignore">o<span style="font:7.0pt "Times New Roman"">   </span></span></span><![endif]><span lang="EN-US" style="color:#1F497D">the min and max zoom levels for each layer<o:p></o:p></span></pre>
<pre style="margin-left:72.0pt;text-indent:-18.0pt;mso-list:l0 level2 lfo2"><![if !supportLists]><span lang="EN-US" style="color:#1F497D"><span style="mso-list:Ignore">o<span style="font:7.0pt "Times New Roman"">   </span></span></span><![endif]><span lang="EN-US" style="color:#1F497D">the min and max tile indexes for each layer and zoom level <o:p></o:p></span></pre>
<pre style="margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span lang="EN-US" style="color:#1F497D"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">   </span></span></span><![endif]><span lang="EN-US" style="color:#1F497D">Extract efficiently all the features of a given tile (with specific x/y indexes) at a given zoom level<o:p></o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D">I am currently reading the MBTILES implementation source code (mbtilesdataset.cpp) and there seems to be quite a lot of tricks internally (for instance with SetSpatialFilter)<o:p></o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D">Would somebody have an example using gdal to extract efficiently a tile for a given layer, given tile index and given zoom ?<o:p></o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D">Regards<o:p></o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D">Christophe<o:p></o:p></span></pre>
<pre style="text-align:justify"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></pre>
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