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<p class=MsoNormal>I have a table with many single ring polygons. Some of the
polygons rings in the table may be contained by other polygons in the same
table. What I would like to do is to assemble all the contained rings into a
single polygon. But it gets a little more convoluted than that. Some of the
rings contained by another poly may contain rings of other poly’s too,
so:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Poly1Ring contains poly2ring, poly3ring and poly4ring<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Poly2Ring contains poly3ring.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>What is the best method to combine these polygons to effectively
cut holes where the rings are contained?<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><br>
Rob.<o:p></o:p></p>
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