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<DIV dir=ltr><FONT face="Times New Roman" color=#000000 size=2>For any individual Abbey, the azimuthal equidistant projection (originally invented by the monk, Postel) might do in either a spherical or an ellipsoidal case. This projection is identical to what is viewed on a radar screen. The French Hatt projection is one variant used for hydrographic projections of harbor surveys in the 19th and early 20th centuries.</FONT></DIV>
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<FONT face=Tahoma size=2><B>From:</B> proj-bounces@lists.maptools.org on behalf of Carlo A. Bertelli (Charta s.r.l.)<BR><B>Sent:</B> Sun 07-Aug-11 16:16<BR><B>To:</B> proj@lists.maptools.org<BR><B>Subject:</B> [Proj] Little sphere projection<BR></FONT><BR></DIV>
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<P><FONT size=2>Hello,<BR>I'm trying a simplistic approach to a topological representation. I'm<BR>mapping the possessions belonging to a group of abbeys in a regional<BR>space. Il works well at a small scale, but when the abbeys are<BR>clustered in major towns, the representation ties properties to the<BR>cluster and not to the single abbey. The fact is that towns (and<BR>clustering) play a significant role in this story (yes this happens in<BR>the 18th century), asks for a better representation.<BR>My idea is analysing each town cluster using a little sphere (or<BR>ellipsoid) centered on the town whith an emisphere that only covers<BR>the space of the region, so to show larger distances in town (so to<BR>distinguish any abbey) and reduced distances far from the town center.<BR>I think it should not be impossible to craft ad hoc projections, but I<BR>have no idea on how to do it. Could someone help me?<BR>TIA<BR>c<BR>_______________________________________________<BR>Proj mailing list<BR>Proj@lists.maptools.org<BR><A href="http://lists.maptools.org/mailman/listinfo/proj">http://lists.maptools.org/mailman/listinfo/proj</A><BR></FONT></P></DIV></BODY></HTML>