<HTML><HEAD><TITLE>Re: [Gvsig_english] world file and on-the fly transformation forvectorlayers</TITLE>
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<DIV><FONT face="Times New Roman" color=#000000 size=3>Hello,</FONT></DIV>
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<DIV><FONT size=2>> Rahkonen Jukka wrote:<BR>> <BR>> > Most simple format could take just source and target<BR>> > coordinates for two or more reference points for performing a<BR>> > simple vector warp.<BR>> <BR>> Actually, for warping the minimum is just one control point.<BR>> <BR>> -Jukka-</FONT><BR></DIV>
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<DIV><FONT face="Times New Roman" color=#000000 size=3>That's an interesting point. I've always though that the only honest transformation is the one done with two control points (keeping proportions and allowing rotation). With just one control point, you are not allowing rotation (it can be useful sometimes, though), and with three points or more, you are stretching the map, so it's not the original map anymore.</FONT></DIV>
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<DIV>As for Ernesto's issue, I think the third solution proposed by Ben is my favorite: the app would say "There is a WLD file available, shall we use it?"</DIV>
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<DIV>Regards,</DIV>
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<DIV><FONT face="Courier New" size=2><FONT face="Times New Roman" size=3>Juan Lucas Domínguez Rubio<BR></FONT>---</FONT></DIV>
<DIV><FONT face="Courier New" size=2><FONT face="Courier New" size=2><FONT face="Courier New" size=2>Prodevelop SL, Valencia (España)</FONT></DIV>
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<DIV><FONT face="Courier New" size=2>Tlf.: 96.351.06.12 -- Fax: 96.351.09.68<BR></FONT><A href="http://www.prodevelop.es/"><FONT face="Courier New" size=2>http://www.prodevelop.es</FONT></A><BR><FONT face="Courier New" size=2>---</FONT></DIV></FONT></DIV></FONT></DIV>
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<FONT face=Tahoma size=2><B>De:</B> gvsig_internacional-bounces@listserv.gva.es en nombre de Rahkonen Jukka<BR><B>Enviado el:</B> jue 30/09/2010 10:45<BR><B>Para:</B> Users and Developers mailing list<BR><B>Asunto:</B> Re: [Gvsig_english] world file and on-the fly transformation forvectorlayers<BR></FONT><BR></DIV>
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<P><FONT size=2>> Rahkonen Jukka wrote:<BR>> <BR>> > Most simple format could take just source and target<BR>> > coordinates for two or more reference points for performing a<BR>> > simple vector warp.<BR>> <BR>> Actually, for warping the minimum is just one control point.<BR>> <BR>> -Jukka-<BR>_______________________________________________<BR>Gvsig_internacional mailing list<BR>Gvsig_internacional@listserv.gva.es<BR><A href="http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional">http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional</A><BR></FONT></P></DIV></BODY></HTML>