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<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2>Margie,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2>Unfortunately I think the answer is no. Most of the
work going on in 1.4 is to improve speed of existing functionality and
reorganize the source to make it more maintainable.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2>Someone please correct me if I am wrong.
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2>I for one would be very elated if we had better 3D support
since CityGML and similar initiatives are becoming more of a hot topic around
here.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=439075015-07102008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=439075015-07102008></SPAN><FONT face=Arial><FONT
color=#0000ff><FONT size=2>Thanks,</FONT></FONT></FONT></DIV>
<DIV><FONT><FONT color=#0000ff><FONT size=2><SPAN
class=439075015-07102008></SPAN></FONT></FONT></FONT><SPAN
class=439075015-07102008></SPAN><FONT face=Arial><FONT color=#0000ff><FONT
size=2>R<SPAN
class=439075015-07102008>egina</SPAN></FONT></FONT></FONT><BR></DIV>
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<FONT face=Tahoma size=2><B>From:</B>
postgis-devel-bounces@postgis.refractions.net
[mailto:postgis-devel-bounces@postgis.refractions.net] <B>On Behalf Of
</B>Huntington, Margaret (US SSA)<BR><B>Sent:</B> Tuesday, October 07, 2008
11:47 AM<BR><B>To:</B> postgis-devel@postgis.refractions.net<BR><B>Subject:</B>
[postgis-devel] Dropped DM (Time) dimension with
intersections<BR></FONT><BR></DIV>
<DIV></DIV><!-- Converted from text/rtf format -->
<P align=left><SPAN lang=en-us><FONT face=Arial size=2>Hello, </FONT></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>Currently I</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>’</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>m using PostGIS
1.3.3. </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>From past discussions</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2> and from
testing</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial
size=2>,</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>both</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>the</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>st_intersection</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>st_extend</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>method</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>s</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2> return 2D</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>results</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2> w</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2>ith</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2> 4D</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>input</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>geometries</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>. As a temporary work-around, I had
hoped</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>st_intersection might work with</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2>
3DM</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>geometries. </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>(Plan was to interpolate the altitude value within the
function call if PostGIS could calculate the time dimension).</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial size=2> I found time
components are also dropped</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us> <FONT face=Arial size=2>by st_i</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2>n</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial
size=2>tersection</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>with 3DM geometries</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>. I abandoned usage
of</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>4D</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>bounding boxes since these too</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>effectively</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>degrade</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>4D geometries down to 2D geometries</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2> (altitude and time
are zeroed out)</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2>.</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us> </SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>polyGeometry geometry;</FONT></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial size=2>
bbGeometry geometry;</FONT></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial size=2>
intersectionGeometry geometry;</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2> </FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> </SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial size=2>
coorddims smallint;</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
</SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> -- both
polygon and linestring have a</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>n expected</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>zmflag</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>value</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>of 1</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2> </FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial size=2> polyGeometry
:= 'SRID=4326;POLYGONM((0 0 0, 0 10 4, 10 10 4, 10 0 0, 0 0
0))'::geometry;</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
</SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> bbGeometry
:= 'SRID=4326;LINESTRINGM(0 0</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us> <FONT face=Arial size=2>1.5</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2>, 10
10</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>2</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial
size=2>)'::geometry;</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial
size=2> </FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> </SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2>
intersectionGeometry := st_intersection(polyGeometry,
bbGeometry);</FONT></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> --
st_intersection method drops the time dimension; zmflag value of
0</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial
size=2> </FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>coorddims :=
st_zmflag(intersectionGeometry);</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial size=2>If I were
to</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>download</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2> the subversion</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us> <FONT face=Arial size=2>snapshot, the</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>current</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>1.4 version, might st_intersection work with either 3DM or 4D
geometries?</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us><FONT
face=Arial size=2> Are bounding boxed</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial size=2>or
st_extend</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>improved for either 3DM or 4D geometries?</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2>
I</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>had incorporated</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
<FONT face=Arial size=2>polygons</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us> <FONT face=Arial size=2>only</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial size=2>as
a</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>possible</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT
face=Arial size=2>work-around</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us> <FONT face=Arial size=2>to the</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial size=2> bounding
box</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us> <FONT face=Arial
size=2>and st_extend 2D limitations</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us><FONT face=Arial size=2>.</FONT></SPAN><SPAN lang=en-us></SPAN><SPAN
lang=en-us></SPAN></P>
<P align=left><SPAN lang=en-us><FONT face=Arial size=2>Margie</FONT></SPAN><SPAN
lang=en-us></SPAN><SPAN lang=en-us><FONT face=Arial
size=2> </FONT></SPAN><SPAN lang=en-us></SPAN><SPAN lang=en-us>
</SPAN></P></BODY></HTML>
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