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<p class="MsoNormal">Hi All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am looking for some direction on if GDAL has the capability has the ability to build a super-polygon from a series of small polygons…I have played a bit with the OGR Geometry classes but I can’t<o:p></o:p></p>
<p class="MsoNormal">seem to quite get what I need.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Let’s start with a simply example.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Polygon A has vertices in (X,Y) format of <0, 0>, < 0,1>, <1,0>, <1,1><o:p></o:p></p>
<p class="MsoNormal">Polygon B has vertices in (x,y) format of < 1,0 >, <1,1>, <2,0>, <2,1><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Since Polygon A and B share a common side with vertices < <1,0> and <1,1> I want to build super polygon that contains the coordinates of the outer perimeter of the points.<o:p></o:p></p>
<p class="MsoNormal">When complete the new polygon C will thus have points <0,0>,<0,1>,<2,0>, <2,1><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I had first looked at OGRPolygon.AddRing wherein A and B above would be OGRLinearRings and then by making a call to C.getExteriorRing() but this seem to report the first ring added.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Am I heading in the correct direction or is this something that I will essentially have to do manually by first creating a OGRLinearRing from the vertices of polygon A, then creating a OGRPolygon to which I execute addRing.<o:p></o:p></p>
<p class="MsoNormal">Then interrogating that ring to see which line segments are common between A and B and removing the ones that are common and adding the line segments that aren’t common.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Bill<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt">++++<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt">William Cassanova | Senior GFS Developer | The Weather Channel | 770.226.2368 | bcassanova@weather.com<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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