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<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>Hi,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>it should be correct. 1 meter is always 1 meter. The
differences between the different projections is, that the meter doesn't
describe the real length.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>EPSG:25832 is a projection, where a meter on map is a meter in
reality.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>For i.e. EPSG:900913 (Google Projection) it's
not.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>Distance Düsseldorf - Hannover </FONT></SPAN></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>EPSG:25832 : 240.9911275436498<BR>EPSG:900913 :
389.3661105393922<BR></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=484344917-06122011><FONT color=#0000ff
size=2 face=Arial>Arnd</FONT></SPAN></DIV><BR>
<DIV dir=ltr lang=de class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>Von:</B> openlayers-users-bounces@lists.osgeo.org
[mailto:openlayers-users-bounces@lists.osgeo.org] <B>Im Auftrag von </B>Robert
Buckley<BR><B>Gesendet:</B> Dienstag, 6. Dezember 2011 08:48<BR><B>An:</B>
users@openlayers.org<BR><B>Betreff:</B> [OpenLayers-Users] Creating an
application with pre-defined mapscales/resolutions<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV
style="BACKGROUND-COLOR: #fff; FONT-FAMILY: arial, helvetica, sans-serif; COLOR: #000; FONT-SIZE: 10pt">
<DIV
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt">Hi,</DIV>
<DIV
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt"><BR></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt">I would
like to have a simple application which delivers wms layers in
scales/resolutions which are not the usual OSM/Google messy scales, but rather
include 1:1000 000 / 1:500 000 / 1:250 000 / 1:100 000 / 1: 50 0000/ 1:10 000,
1: 5000 and 1:2,500. To make this even more difficult I need to do this in
EPSG:25832 the european standard ETRS/ UTM zone 32 projected CRS with units of
meters</DIV>
<DIV
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt"><BR></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt">As far
as I have understood, this is fully dependant on the basemap resolutions. As
this is pure mathematical I would like to show what I think I have learnt and
wait for comments....</DIV>
<DIV
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt"><BR></DIV>
<DIV
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt"><BR></DIV>
<DIV><FONT class=Apple-style-span size=2 face="arial, helvetica, sans-serif">R
= </FONT><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: small"
class=Apple-style-span>resolution</SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: small"
class=Apple-style-span> </SPAN></DIV>
<DIV><FONT class=Apple-style-span size=2 face="arial, helvetica, sans-serif">S
= </FONT><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: small"
class=Apple-style-span>scale</SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span> as denominator</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>IPU = </SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>OpenLayers.INCHES_PER_UNIT[units] = 39.3701 inches in a
meter</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>DPI = </SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>OpenLayers.DOTS_PER_INCH = 25.4 / 0.28 =
90.71428571428571 ( 1 inch = 25.4 mm / standardized pixel size of
0.28x0.28mm)</SPAN></DIV>
<DIV><FONT class=Apple-style-span size=2 face="arial, helvetica, sans-serif"><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)">this must be set in the application code "OpenLayers.DOTS_PER_INCH = 25.4 / 0.28" = <SPAN style="LINE-HEIGHT: normal; FONT-FAMILY: arial, helvetica, sans-serif; WHITE-SPACE: normal; COLOR: rgb(0,0,0); FONT-SIZE: 13px" class=Apple-style-span>90.7142 o</SPAN>therwise, the scale factor would be 72 / 90.7143 = 0.7937.</PRE></FONT></DIV>
<DIV><FONT class=Apple-style-span size=2
face="arial, helvetica, sans-serif"><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span size=2 face="arial, helvetica, sans-serif">R=
S / IPU * DPI</FONT></DIV>
<DIV><FONT class=Apple-style-span size=2
face="arial, helvetica, sans-serif"><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span size=2
face="arial, helvetica, sans-serif">using this formular, we are basically
working out how many pixels there are in 1 meter of screen, to so find out how
many pixels there are in 1000000 meters of screen we use...</FONT></DIV>
<DIV><FONT class=Apple-style-span size=2
face="arial, helvetica, sans-serif"><BR></FONT></DIV>
<DIV>[Scale 1:1000 000]</DIV>
<DIV><BR></DIV>
<DIV>R = 1000000 / (39.2701 * <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>90.71428571428571) </SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>R =</SPAN>1000000 <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span> / 3562.359071428571260271</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>R = 280.712859077111976006937033</SPAN></DIV>
<DIV><FONT class=Apple-style-span><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span>[Scale 1:500000]<BR></FONT></DIV>
<DIV>
<DIV>R = 500000 / (39.2701 * <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>90.71428571428571) </SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>R =</SPAN>500000 <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span> / 3562.359071428571260271</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>R = 140.356429538555988003468517</SPAN></DIV>
<DIV><BR></DIV>
<DIV>...etc for the <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=Apple-style-span>1:250 000 / 1:100 000 ...</SPAN></DIV></DIV>
<DIV><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)"><BR></PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)"><BR></PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)">What bothers me though, is that every EPSG code with units of meters will have the same resolutions. Is this
correct?</PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)"><BR></PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)"><BR></PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)">sources: </PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)"><A style="LINE-HEIGHT: normal; FONT-FAMILY: 'Times New Roman'; WHITE-SPACE: normal" href="http://geowebcache.org/docs/current/concepts/gridsets.html">http://geowebcache.org/docs/current/concepts/gridsets.html</A></PRE><PRE style="TEXT-ALIGN: justify; LINE-HEIGHT: 20px; COLOR: rgb(34,34,34)"><A href="http://wiki.osgeo.org/wiki/WMS_Tiling_Client_Recommendation">http://wiki.osgeo.org/wiki/WMS_Tiling_Client_Recommendation</A><BR></PRE></DIV></DIV></BODY></HTML>