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<p class="MsoNormal"><span lang="EN-US">Hi<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">I’m playing around with the QGIS (d01bfd1) snap functionalities in python and I’m trying to get it return all the segments in the vicinity of the point of interest.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"> sl = QgsSnapper.SnapLayer()</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black">
<u>sl</u>.mLayer = canvas.currentLayer()</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"> sl.mTolerance =
</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:maroon">50</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"> sl.snapTo = QgsSnapper.SnapToSegment</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
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</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"> snapper = QgsSnapper(canvas.mapSettings())</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"> snapper.setSnapLayers([sl])</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"> snapper.setSnapMode = QgsSnapper.SnapWithResultsWithinTolerances<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> (retval, result) = snapper.snapMapPoint(point_of_interest_in_map_coordinates)<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">If I choose a point near two coinciding polygon edges I only get one result.<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">If I choose a point near a place where three different polygon edges meet at the same point, I still only get one result.<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">I though using the snap mode SnapWithResultsWithinTolerances (or even in this case SnapWithResultsForSamePosition) would allow the snapper to give me more than one result?<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"><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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