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Hi all,<br>
<br>
Apologies for reviving this thread (below), but does anyone have a
solution other than using a different data format? I ask because I
will be do some teaching using QGIS and want to work with shapefiles
for that.<br>
<br>
This is a problem that's emerged for me only with recent versions of
QGIS, so something must have changed to cause the behavior. Might it
be at the level of GDAL?<br>
<br>
Best wishes,<br>
<br>
Peter<br>
<br>
<br>
<br>
<br>
<div class="moz-signature">-- <br>
Peter Aldhous, PhD<br>
Science journalist<br>
Contributor, <a href="https://medium.com/matter">MATTER</a><br>
phone: 415 800 3471<br>
cell: 415 503 7323<br>
email: <a href="mailto:peter@peteraldhous.com">peter@peteraldhous.com</a><br>
web: <a href="http://www.peteraldhous.com/">www.peteraldhous.com</a><br>
twitter: <a href="https://twitter.com/paldhous">@paldhous</a><br>
<br>
<pre wrap="">I can verify this same behavior on Win7 with QGIS 2.4 64b. I think it
has to do with the shapes crossing the 180^(o) line. If you zoom in to
a smaller area that includes only countries in one hemisphere, the
borders look OK. Also, it's not only Robinson and Mollweide: any
global projection will show strange trapezoids (even "Google" mercator)
I also see that if you use the <b class="moz-txt-star"><span class="moz-txt-tag">*</span>spatialite database file<span class="moz-txt-tag">*</span></b> from
naturalearthdata.org this problem disappears. You can switch to other
world projections with no problem.
On 29/06/2014 16:59, Peter Aldhous wrote:
</pre>
<blockquote type="cite" style="color: #000000;">
<pre wrap="">I don't think the image came through, but the problem is that every
polygon ends up as a trapezoid, so I end up with a collection of
overlapping trapezoids
Peter Aldhous, PhD
Science journalist
Contributor, MATTER <a class="moz-txt-link-rfc2396E" href="https://www.medium.com/matter"><https://www.medium.com/matter></a>
phone: 415 800 3471
cell: 415 503 7323
email: <a class="moz-txt-link-abbreviated" href="mailto:peter@peteraldhous.com">peter@peteraldhous.com</a> <a class="moz-txt-link-rfc2396E" href="mailto:peter@peteraldhous.com"><mailto:peter@peteraldhous.com></a>
web: <a class="moz-txt-link-abbreviated" href="http://www.peteraldhous.com">www.peteraldhous.com</a> <a class="moz-txt-link-rfc2396E" href="http://www.peteraldhous.com/"><http://www.peteraldhous.com/></a>
twitter: @paldhous <a class="moz-txt-link-rfc2396E" href="https://twitter.com/paldhous"><https://twitter.com/paldhous></a>
On 6/29/14, 6:54 AM, Peter Aldhous wrote:
</pre>
<blockquote type="cite" style="color: #000000;">
<pre wrap="">Hi all,
I'm using the KyngChaos install of QGIS on the Mac (Mavericks and
Lion, on different machines), and I've been having problems with
projections including Robinson and Mollweide from QGIS 2.2 onwards.
Everything was fine in QGIS 2.0, but in 2.2 and 2.4, re-projecting a
world Natural Earth shapefile to a Robinson projection, for example,
gives this:
Any idea what might be going on, and how to fix it?
Thanks,
--
Peter Aldhous, PhD
Science journalist
Contributor, MATTER <a class="moz-txt-link-rfc2396E" href="https://www.medium.com/matter"><https://www.medium.com/matter></a>
phone: 415 800 3471
cell: 415 503 7323
email: <a class="moz-txt-link-abbreviated" href="mailto:peter@peteraldhous.com">peter@peteraldhous.com</a> <a class="moz-txt-link-rfc2396E" href="mailto:peter@peteraldhous.com"><mailto:peter@peteraldhous.com></a>
web: <a class="moz-txt-link-abbreviated" href="http://www.peteraldhous.com">www.peteraldhous.com</a> <a class="moz-txt-link-rfc2396E" href="http://www.peteraldhous.com/"><http://www.peteraldhous.com/></a>
twitter: @paldhous <a class="moz-txt-link-rfc2396E" href="https://twitter.com/paldhous"><https://twitter.com/paldhous></a>
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