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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Hi Traian!!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Thanks for the info..!!!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>So the things I need to do are:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=1 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Find
the overall map extent.<o:p></o:p></span></font></li>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Find
the predefined zoom scales <o:p></o:p></span></font></li>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>For
each of these zoom scales, I need to find the number of tiles x, no
of tiles y.( using the formulae that u specified)<o:p></o:p></span></font></li>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Then
I need to loop through these and call GetTile( map, baselayergroup,
column, row)<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>However, to find the no. of tiles x and y,
I need to know the map width and height in meters. I guess I can get the map
height and width, in double, from the map extent. Can you tell me how to
convert these into pixels..?Please help!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Thanks in advance<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Farah<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<div>
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<hr size=2 width="100%" align=center tabindex=-1>
</span></font></div>
<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> Traian Stanev
[mailto:traian.stanev@autodesk.com] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, August 31, 2006
6:16 PM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">users@mapguide.osgeo.org</st1:PersonName><br>
<b><span style='font-weight:bold'>Subject:</span></b> RE: [mapguide-users]
Pre-Genererate tiles for the entire map at all pre-defined zoom scales</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>Hi Farah.</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>The upper left corner of the extents of
the map corresponds to tile (0,0). Then tile (1,0) is to the right of that and
tile (0,1) is under tile (0,0).</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>So assuming you know the extents of your
map, you can calculate how many tiles it spans at the given scale, using the
following</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>number of tiles x = map width in
meters / ( 0.079375 * map_scale)</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>number of tiles y = map height in meters /
( 0.079375 * map_scale)</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>where 0.079375 = [inch to meter] / image
DPI * tile size = 0.0254 / 96 * 300.</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>This assumes you know the scale
factor that converts your map width and height to meters. You can get
this from the coordinate system of the map if you don't know it, but it's much
easier to just plug in the number into this equation.</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>Also have in mind that you can also
request tiles beyond the map extent (for example tile (-1, -1), however, there
is probably no point to cache them unless you have valid data outside your
initial map extents.</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>Traian</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div class=MsoNormal align=center style='text-align:center'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabIndex=-1>
</span></font></div>
<p class=MsoNormal style='margin-bottom:12.0pt'><b><font size=2 face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> Farah [mailto:farah@egovernments.org]
<br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, August 31, 2006
2:52 AM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">users@mapguide.osgeo.org</st1:PersonName><br>
<b><span style='font-weight:bold'>Subject:</span></b> [mapguide-users]
Pre-Genererate tiles for the entire map at all pre-defined zoom scales</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi friends!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am trying to pre-generate tiles, of the base map group
layers,at various zoom levels and pre-populate the TileCache , so as to improve
the performance.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I guess I have to use the function:<o:p></o:p></span></font></p>
<table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0>
<tr>
<td nowrap valign=top style='padding:0in 0in 0in 0in'>
<p class=MsoNormal align=right style='text-align:right'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>virtual <a
href="https://mapguide.osgeo.org/nonav/docs/webapi/d8/d50/class_mg_byte_reader.html">MgByteReader</a>
* <o:p></o:p></span></font></p>
</td>
<td valign=bottom style='padding:0in 0in 0in 0in'>
<p class=MsoNormal><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'><a
href="https://mapguide.osgeo.org/nonav/docs/webapi/df/dba/class_mg_tile_service_a0fab3452d48d4a4abeedb8dc2c18611.html#a0fab3452d48d4a4abeedb8dc2c18611">GetTile</a>
(<a
href="https://mapguide.osgeo.org/nonav/docs/webapi/da/df8/class_mg_map.html">MgMap</a>
*map, <a
href="https://mapguide.osgeo.org/nonav/docs/webapi/da/d10/_common_defs_8h_2697935ae7be4121104b37ff513b810b.html#2697935ae7be4121104b37ff513b810b">CREFSTRING</a>
baseMapLayerGroupName, <a
href="https://mapguide.osgeo.org/nonav/docs/webapi/da/d10/_common_defs_8h_0cb58e7e6f0bad369840a52e54a56ae0.html#0cb58e7e6f0bad369840a52e54a56ae0">INT32</a>
tileColumn, <a
href="https://mapguide.osgeo.org/nonav/docs/webapi/da/d10/_common_defs_8h_0cb58e7e6f0bad369840a52e54a56ae0.html#0cb58e7e6f0bad369840a52e54a56ae0">INT32</a>
tileRow)=0<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
</td>
</tr>
</table>
<pre style='line-height:135%;background:#EEEEEE'><font size=2 face=Arial><span
style='font-size:10.0pt;line-height:135%;font-family:Arial'>I read from a previous post that <font
color=black><span style='color:black'>Tile column and row are related to map coordinates in the function<o:p></o:p></span></font></span></font></pre>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>called
MgServerRenderingService::RenderTile. However, I don’t get how the tile
column and row are associated with the map coordinates. Does anyone have any
idea about this? Please help!!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>Thanks in advance,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>Farah</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>
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