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<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>Sam,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>Sam,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>Not to my knowledge. There are a couple of hurdles we
need to jump before that step.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>The big one:</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>GEOS is predominantly 2-D engine: PostGIS buffer and
many other functions piggy -back on that.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>so the big question is whether to expand GEOS to handle new 3d
types thus deviating more from its JTS roots or use another engine like Boost or
CGAL.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>The other option is just to build into PostGIS core, but not
sure how much effort is involved there.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>Olivier is working on much of the 3D
stuff and many of the PostGIS core dev are having a code sprint
in Paris.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>I think there is still space left if you want to chat up
with them and you can make the trip.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial><A
href="http://trac.osgeo.org/postgis/wiki/DevWikiEvent">http://trac.osgeo.org/postgis/wiki/DevWikiEvent</A></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>Hope that helps,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial>Regina</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial><A
href="http://www.postgis.us">http://www.postgis.us</A></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=490471608-02052012><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV><BR>
<BLOCKQUOTE
style="BORDER-LEFT: #0000ff 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px"
dir=ltr>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B>
postgis-devel-bounces@postgis.refractions.net
[mailto:postgis-devel-bounces@postgis.refractions.net] <B>On Behalf Of </B>Sam
Hariton<BR><B>Sent:</B> Tuesday, May 01, 2012 4:06 PM<BR><B>To:</B>
postgis-devel@postgis.refractions.net<BR><B>Subject:</B> [postgis-devel]
ST_Buffer in 3D supporting Z<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV class=gmail_quote>Is anyone looking at adding the ability for st_buffer
to keep Z coordinates as well for 3-dimensional spaces? If so, I'd like
to help.<BR><BR>The Postgis 2.0 docs state: <SPAN
style="BACKGROUND-COLOR: rgb(228,247,221); FONT-FAMILY: 'Lucida Grande',Verdana,Geneva,Arial,Helvetica,sans-serif; COLOR: rgb(46,46,46); FONT-SIZE: 13px">This
function ignores the third dimension (z) and will always give a 2-d buffer
even when presented with a 3d-geometry.</SPAN><BR><BR>Right now <BR><BR>
<BLOCKQUOTE
style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex"
class=gmail_quote><SPAN>
<DIV>select st_astext(st_buffer(geomfromEWKT('POINT(0 0
0)'),1));</DIV></SPAN></BLOCKQUOTE><BR>Generates a flat Polygon/Circle of
radius 1 (completely dropping the z dimension):<BR><BR> POLYGON((1
0,0.980785280403231 -0.195090322016128,0.923879532511287
-0.382683432365089,0.831469612302546 -0.555570233019602,0.707106781186548
-0.707106781186547,0.555570233019603 -0.831469612302545,0.382683432365091
-0.923879532511286,0.19509032201613 -0.98078528040323,1.61554255216634e-15
-1,-0.195090322016126 -0.980785280403231,-0.382683432365088
-0.923879532511288,-0.555570233019601 -0.831469612302546,-0.707106781186546
-0.707106781186549,-0.831469612302544 -0.555570233019604,-0.923879532511286
-0.382683432365092,-0.98078528040323 -0.195090322016131,-1
-3.23108510433268e-15,-0.980785280403231
0.195090322016125,-0.923879532511288<BR> 0.382683432365086,-0.831469612302547
0.555570233019599,-0.70710678118655 0.707106781186545,-0.555570233019606
0.831469612302543,-0.382683432365094 0.923879532511285,-0.195090322016132
0.98078528040323,-3.73640463187386e-15 1,0.195090322016125
0.980785280403231,0.382683432365087 0.923879532511288,0.5555702330196
0.831469612302547,0.707106781186545 0.70710678118655,0.831469612302544
0.555570233019604,0.923879532511286 0.382683432365092,0.98078528040323
0.19509032201613,1 0))<BR><BR>Whereas, if it had z support it should actually
generate a Polyhedral Surface/Sphere of radius 1 centered on (0 0 0)<FONT
color=#888888><BR></FONT></DIV>
<DIV class=gmail_quote><BR></DIV>
<DIV class=gmail_quote> - Sam</DIV>
<DIV class=gmail_quote><BR></DIV></BLOCKQUOTE></BODY></HTML>