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<div dir="ltr" data-setdir="false">Hi Marian,</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">I think you are looking at an abstract method, that is implemented differently for each type of geometry.</div><div dir="ltr" data-setdir="false">So you need to dig deeper into the code to find the specific implementation of the bounding box or boundary method for polygons.</div><div dir="ltr" data-setdir="false">The link below at line 138 gives the boundary method for the multipolygonv2 geometry.</div><div dir="ltr" data-setdir="false"><a href="https://qgis.org/api/2.18/qgsmultipolygonv2_8cpp_source.html#l00138" rel="nofollow" target="_blank">https://qgis.org/api/2.18/qgsmultipolygonv2_8cpp_source.html#l00138</a><br></div><div><br></div><div dir="ltr" data-setdir="false">This may not specifically be what you are looking for, but hopefully it will help you find it.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">-Thayer</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div><div><br></div></div><div id="ydp36c73fd3yahoo_quoted_2749264778" class="ydp36c73fd3yahoo_quoted"><div style="font-family:'Helvetica Neue', Helvetica, Arial, sans-serif;font-size:13px;color:#26282a;"><div><div dir="ltr">Message: 3<br></div><div dir="ltr">Date: Thu, 8 Oct 2020 18:17:25 +0000<br></div><div dir="ltr">From: "Tudorache, Marian" <<a href="mailto:Marian.Tudorache@navcanada.ca" rel="nofollow" target="_blank">Marian.Tudorache@navcanada.ca</a>><br></div><div dir="ltr">To: "<a href="mailto:qgis-user@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user@lists.osgeo.org</a>" <<a href="mailto:qgis-user@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user@lists.osgeo.org</a>>,<br></div><div dir="ltr"> "Qgis-user <<a href="mailto:qgis-user-bounces@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user-bounces@lists.osgeo.org</a>><br></div><div dir="ltr"> (<a href="mailto:qgis-user-bounces@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user-bounces@lists.osgeo.org</a>)"<br></div><div dir="ltr"> <<a href="mailto:qgis-user-bounces@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user-bounces@lists.osgeo.org</a>>,<br></div><div dir="ltr"> "<a href="mailto:qgis-user-request@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user-request@lists.osgeo.org</a>"<br></div><div dir="ltr"> <<a href="mailto:qgis-user-request@lists.osgeo.org" rel="nofollow" target="_blank">qgis-user-request@lists.osgeo.org</a>><br></div><div dir="ltr">Subject: [Qgis-user] bounding box algorithm<br></div><div dir="ltr">Message-ID:<br></div><div dir="ltr"> <<a href="mailto:YTBPR01MB36777A269FA5AB1C954B8F23E60B0@YTBPR01MB3677.CANPRD01.PROD.OUTLOOK.COM" rel="nofollow" target="_blank">YTBPR01MB36777A269FA5AB1C954B8F23E60B0@YTBPR01MB3677.CANPRD01.PROD.OUTLOOK.COM</a>><br></div><div dir="ltr"> <br></div><div dir="ltr">Content-Type: text/plain; charset="utf-8"<br></div><div dir="ltr"><br></div><div dir="ltr">Hi,<br></div><div dir="ltr"><br></div><div dir="ltr">The question is for the developers of QGIS.<br></div><div dir="ltr">In my python classes I use a lot the boundingBox function for QgsGeometry class.<br></div><div dir="ltr">I would like to know if it is possible to see the algorithm for this function.<br></div><div dir="ltr"><br></div><div dir="ltr">I found this but it is not really the algorithm<br></div><div dir="ltr"><br></div><div dir="ltr"> 858<<a href="https://qgis.org/api/2.18/classQgsGeometry.html#adfc04c94b51cdeb55942b699fdd4d564" rel="nofollow" target="_blank">https://qgis.org/api/2.18/classQgsGeometry.html#adfc04c94b51cdeb55942b699fdd4d564</a>> QgsRectangle<<a href="https://qgis.org/api/2.18/classQgsRectangle.html" rel="nofollow" target="_blank">https://qgis.org/api/2.18/classQgsRectangle.html</a>> QgsGeometry::boundingBox<<a href="https://qgis.org/api/2.18/classQgsGeometry.html#adfc04c94b51cdeb55942b699fdd4d564" rel="nofollow" target="_blank">https://qgis.org/api/2.18/classQgsGeometry.html#adfc04c94b51cdeb55942b699fdd4d564</a>>() const<br></div><div dir="ltr"> 859 {<br></div><div dir="ltr"> 860 if ( d->geometry<<a href="https://qgis.org/api/2.18/structQgsGeometryPrivate.html#ac49a8dd9cb78a9d041d1a46ac6a7ef15" rel="nofollow" target="_blank">https://qgis.org/api/2.18/structQgsGeometryPrivate.html#ac49a8dd9cb78a9d041d1a46ac6a7ef15</a>> )<br></div><div dir="ltr"> 861 {<br></div><div dir="ltr"> 862 return d->geometry<<a href="https://qgis.org/api/2.18/structQgsGeometryPrivate.html#ac49a8dd9cb78a9d041d1a46ac6a7ef15" rel="nofollow" target="_blank">https://qgis.org/api/2.18/structQgsGeometryPrivate.html#ac49a8dd9cb78a9d041d1a46ac6a7ef15</a>>->boundingBox<<a href="https://qgis.org/api/2.18/classQgsAbstractGeometryV2.html#ac6806e752aeda4f347741a0c7eb37167" rel="nofollow" target="_blank">https://qgis.org/api/2.18/classQgsAbstractGeometryV2.html#ac6806e752aeda4f347741a0c7eb37167</a>>();<br></div><div dir="ltr"> 863 }<br></div><div dir="ltr"> 864 return QgsRectangle<<a href="https://qgis.org/api/2.18/classQgsRectangle.html" rel="nofollow" target="_blank">https://qgis.org/api/2.18/classQgsRectangle.html</a>>();<br></div><div dir="ltr"> 865 }<br></div><div dir="ltr"> 866<br></div><div dir="ltr">Where<br></div><div dir="ltr">I create some polygons with QGIS which are exported to another system which use a bounding box formula that gives infinity.<br></div><div dir="ltr">The other system includes a check of the South Pole in the bounding box it also takes in consideration the orientation of the polygon coordinates.<br></div><div dir="ltr">It seems in one of the orientation the South Pole is inside the bounding box and if I switch the orientation the South Pole is not anymore inside.<br></div><div dir="ltr">QGIS seems to be immune of how the coordinates are oriented. Regardless of the order QGIS gives a finite bounding box without having a South Pole inside.<br></div><div dir="ltr"><br></div><div dir="ltr">Can someone help me?<br></div><div dir="ltr">Thank you,<br></div><div dir="ltr">Marian<br></div><div dir="ltr">Anyone can help me?<br></div><div dir="ltr"><br></div><div dir="ltr">________________________________</div></div>
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