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<DIV dir=ltr align=left><SPAN class=646530913-23052006><FONT face=Arial
color=#0000ff size=2>One big difference is that GETTILE uses a different
labeling algorithm which attempts to avoid problems with labels spanning
multiple tiles. You will likely get labeling artifacts if you are tiling
WMS requests for data that is labeled. How important is that in your
case?</FONT></SPAN></DIV>
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<DIV dir=ltr align=left><SPAN class=646530913-23052006><FONT face=Arial
color=#0000ff size=2>The tile size in MG is currently set to 300x300 pixels. We
chose a bigger size because labeling would behave better the bigger tiles are,
there would be less http requests made to the server, and the set-up time
overhead to draw a map image is usually a lot longer than the actual time it
takes to draw the geometry, so by having bigger tiles that overhead is
distributed across more features.</FONT></SPAN></DIV>
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<DIV dir=ltr align=left><SPAN class=646530913-23052006><FONT face=Arial
color=#0000ff size=2>However, I see that for overlay with Google Maps, the
ability to set tile size down to 256 may be useful, especially if you expect
that caching the tiles would give a significant performance
boost.</FONT></SPAN></DIV>
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<DIV dir=ltr align=left><SPAN class=646530913-23052006><FONT face=Arial
color=#0000ff size=2>Traian</FONT></SPAN></DIV>
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<FONT face=Tahoma size=2><B>From:</B> Andy Morsell
[mailto:amorsell@spatialgis.com] <BR><B>Sent:</B> Monday, May 22, 2006 11:35
PM<BR><B>To:</B> users@mapguide.osgeo.org<BR><B>Subject:</B> RE:
[mapguide-users] WMS Polygon clipping problems<BR></FONT><BR></DIV>
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<DIV dir=ltr align=left><SPAN class=060512203-23052006><FONT face=Arial
color=#0000ff size=2>Regarding people making tiles on their own: with Google
Maps, if one wants to add their own layers, they have to use the GTileLayer
interface. By definition the Google Maps API automatically makes one call
to the layer source per 256x256 pixel tile. I don't think there is a way
to override this and instead use a visible extent overlay. It does look
like you might be able to change the tile size, but you are stuck with tiles
regardless. So, if using MGOS as the source, we have to use one WMS call
per tile or possibly use the GETTILEIMAGE operation. I have not
experimented much with the latter and would rather stick with WMS calls anyway
for conformity.</FONT></SPAN></DIV>
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<P><SPAN lang=en-us><FONT face=Tahoma size=1>Andy </FONT></SPAN><BR></P>
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<FONT face=Tahoma size=2><B>From:</B> Traian Stanev
[mailto:traian.stanev@autodesk.com] <BR><B>Sent:</B> Monday, May 22, 2006 5:33
PM<BR><B>To:</B> users@mapguide.osgeo.org;
users@mapguide.osgeo.org<BR><B>Subject:</B> RE: [mapguide-users] WMS Polygon
clipping problems<BR></FONT><BR></DIV>
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<P><FONT size=2>OK. I'll check what can be done. It's really a one line change
when it comes down to it, but I'm not sure what other code calls that function
that might be affected. Since people seem to make tiles on their own, the change
is probably worth the performance loss this change
entails...<BR><BR>Traian<BR><BR><BR>-----Original
Message-----<BR>From: Andy Morsell [<A
href="mailto:amorsell@spatialgis.com">mailto:amorsell@spatialgis.com</A>]<BR>Sent:
Mon 5/22/2006 8:22 PM<BR>To:
users@mapguide.osgeo.org<BR>Cc: <BR>Subject:
RE: [mapguide-users] WMS Polygon clipping problems<BR><BR>Traian,<BR>This is
specific to WMS. The screenshot is from Google Maps where the tiles<BR>are
individual WMS calls to MapGuide Open
Source.<BR><BR>Thanks.<BR><BR><BR>Andy<BR><BR><BR>
_____ <BR><BR>From: Traian Stanev [<A
href="mailto:traian.stanev@autodesk.com">mailto:traian.stanev@autodesk.com</A>]<BR>Sent:
Monday, May 22, 2006 4:58 PM<BR>To: users@mapguide.osgeo.org;
users@mapguide.osgeo.org<BR>Subject: RE: [mapguide-users] WMS Polygon clipping
problems<BR><BR><BR><BR><BR>This is strange. For WMS I can see how it would
happen. However, for a<BR>regular tiled map, we turn off polygon clipping
to avoid this. Are you<BR>using a regular tiled map or is this screenshot from
WMS?<BR><BR>Traian<BR><BR><BR>-----Original Message-----<BR>From:
Andy Morsell [<A
href="mailto:amorsell@spatialgis.com">mailto:amorsell@spatialgis.com</A>]<BR>Sent:
Mon 5/22/2006 6:28 PM<BR>To:
users@mapguide.osgeo.org<BR>Cc: <BR>Subject:
[mapguide-users] WMS Polygon clipping problems<BR><BR>There is an older thread
on this topic at:<BR><A
href="https://mapguide.osgeo.org/servlets/ReadMsg?list=users">https://mapguide.osgeo.org/servlets/ReadMsg?list=users</A><BR><<A
href="https://mapguide.osgeo.org/servlets/ReadMsg?list=users&msgNo=488">https://mapguide.osgeo.org/servlets/ReadMsg?list=users&msgNo=488</A>><BR>&msgNo=488<BR><BR>I
am experiencing this problem as well when working in a tiled
environment.<BR>This screenshot illustrates the problem where there are several
large<BR>polygons that have boundaries drawn at the clipping edges. I did
not see an<BR>issue in Project Tracker about this and just wanted to re-raise
the issue to<BR>ensure that it is addressed soon.<BR><BR>Thank you.<BR><BR>Andy
Morsell, P.E.<BR>Spatial Integrators, Inc.<BR><A
href="http://www.SpatialGIS.com">http://www.SpatialGIS.com</A><BR><BR><BR><BR><BR><BR><BR><BR></FONT></P></BODY></HTML>