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<DIV dir=ltr align=left><SPAN class=296231019-06122011><FONT color=#0000ff
size=2 face=Arial>Hi,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=296231019-06122011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=296231019-06122011><FONT color=#0000ff
size=2 face=Arial>it's up to you, what resolutions or scales you want take. How
it best match in your map div.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=296231019-06122011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=296231019-06122011><FONT color=#0000ff
size=2 face=Arial>The commercial layers use a resolution array with
maxResolution=156543.0339/zoomLevel with zoomLevel = 0 - n.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=296231019-06122011></SPAN><SPAN
class=296231019-06122011></SPAN><FONT face=Arial><FONT color=#0000ff><FONT
size=2>A<SPAN class=296231019-06122011>s far as I know for maxResolution the
world match in a square of 256x256 pixel.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>For EPSG:4326 OL suggest a maxResolution=1.40625 =
360/256. The world match in a rectangle of 256x128
pixel.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>It's a practical choice, the world boundary is always a
tile boundary.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>I use</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>map.layers[0].resolutions => [500, 250, 125, 62.5,
31.25, 15.625, 7.8125, 3.90625, 1.953125, 0.9765625, 0.48828125, 0.244140625,
0.1220703125, 0.06103515625, 0.030517578125,
0.0152587890625];</SPAN></FONT></FONT></FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>that is in scales<BR>map.layers[0].scales =>
[1417323.5999999999, 708661.7999999999, 354330.89999999997, 177165.44999999998,
88582.72499999999, 44291.362499999996, 22145.681249999998, 11072.840624999999,
5536.420312499999, 2768.2101562499997, 1384.1050781249999, 692.0525390624999,
346.02626953124997, 173.01313476562498, 86.50656738281249,
43.253283691406246];<BR></SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>to display Nordrhein-Westfalen in my map with a size of
900x600 pixel. </SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>It's a practical choice. For the maxResolution=500 NRW
matches in the map div.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>If you declare a maxExtent in the map options and set
resolution to auto, OL calculates a resolution from the maxExtent and the map
div.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>So I would think, it's always a practical choice, what
resolution you take.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>Viele Grüße,</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=296231019-06122011>Arnd</DIV></SPAN></FONT></FONT></FONT>
<DIV dir=ltr align=left><BR></DIV>
<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 19:15<BR><B>An:</B>
users@openlayers.org<BR><B>Betreff:</B> Re: AW: [OpenLayers-Users] Creating an
application with pre-definedmapscales/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"><SPAN>Hi,</SPAN></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif"><SPAN><BR></SPAN></DIV>
<DIV
style="FONT-FAMILY: arial, helvetica, sans-serif"><SPAN>Thanks.</SPAN></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif"><SPAN><BR></SPAN></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif"><SPAN><SPAN
style="FONT-FAMILY: Arial; COLOR: rgb(0,0,255); FONT-SIZE: 13px"
class=Apple-style-span>"The differences between the different projections is,
that the meter doesn't describe the real length." ...ok I think I see...you mean
that google distorted the projection so it fits nicely in a square whereas the
others are "real" projected coordinate systems?</SPAN><BR></SPAN></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif"><SPAN><SPAN
style="FONT-FAMILY: Arial; COLOR: rgb(0,0,255); FONT-SIZE: 13px"
class=Apple-style-span><BR></SPAN></SPAN></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial>But what I was really
asking is that why have I seen so many different resolutions for various
maps.</FONT></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial>cheers,</FONT></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial>Rob</FONT></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial><BR></FONT></DIV>
<DIV><FONT class=Apple-style-span color=#0000ff face=Arial>.</FONT></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif"><BR></DIV>
<DIV style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 10pt">
<DIV
style="FONT-FAMILY: 'times new roman', 'new york', times, serif; FONT-SIZE: 12pt"><FONT
size=2 face=Arial>
<HR SIZE=1>
<B><SPAN style="FONT-WEIGHT: bold">Von:</SPAN></B> Arnd Wippermann
<arnd.wippermann@web.de><BR><B><SPAN
style="FONT-WEIGHT: bold">An:</SPAN></B> 'Robert Buckley'
<robertdbuckley@yahoo.com> <BR><B><SPAN
style="FONT-WEIGHT: bold">Cc:</SPAN></B> users@openlayers.org <BR><B><SPAN
style="FONT-WEIGHT: bold">Gesendet:</SPAN></B> 19:01 Dienstag, 6.Dezember
2011<BR><B><SPAN style="FONT-WEIGHT: bold">Betreff:</SPAN></B> AW:
[OpenLayers-Users] Creating an application with pre-defined
mapscales/resolutions<BR></FONT><BR>
<DIV id=yiv1492762737>
<DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial>Hi,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><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=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><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=yiv1492762737484344917-06122011><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=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial>Distance Düsseldorf - Hannover
</FONT></SPAN></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><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=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=yiv1492762737484344917-06122011><FONT
color=#0000ff size=2 face=Arial>Arnd</FONT></SPAN></DIV><BR>
<DIV dir=ltr lang=de class=yiv1492762737OutlookMessageHeader 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
style="BACKGROUND-COLOR: rgb(255,255,255); FONT-FAMILY: arial, helvetica, sans-serif; COLOR: rgb(0,0,0); 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=yiv1492762737Apple-style-span size=2
face="arial, helvetica, sans-serif">R = </FONT><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: small"
class=yiv1492762737Apple-style-span>resolution</SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: small"
class=yiv1492762737Apple-style-span> </SPAN></DIV>
<DIV><FONT class=yiv1492762737Apple-style-span size=2
face="arial, helvetica, sans-serif">S = </FONT><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: small"
class=yiv1492762737Apple-style-span>scale</SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span> as denominator</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span>IPU = </SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-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=yiv1492762737Apple-style-span>DPI = </SPAN><SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-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=yiv1492762737Apple-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=yiv1492762737Apple-style-span>90.7142 o</SPAN>therwise, the scale factor would be 72 / 90.7143 = 0.7937.</PRE></FONT></DIV>
<DIV><FONT class=yiv1492762737Apple-style-span size=2
face="arial, helvetica, sans-serif"><BR></FONT></DIV>
<DIV><FONT class=yiv1492762737Apple-style-span size=2
face="arial, helvetica, sans-serif">R= S / IPU * DPI</FONT></DIV>
<DIV><FONT class=yiv1492762737Apple-style-span size=2
face="arial, helvetica, sans-serif"><BR></FONT></DIV>
<DIV><FONT class=yiv1492762737Apple-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=yiv1492762737Apple-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=yiv1492762737Apple-style-span>90.71428571428571) </SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span>R =</SPAN>1000000 <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span> / 3562.359071428571260271</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span>R
= 280.712859077111976006937033</SPAN></DIV>
<DIV><FONT class=yiv1492762737Apple-style-span><BR></FONT></DIV>
<DIV><FONT class=yiv1492762737Apple-style-span><BR></FONT></DIV>
<DIV><FONT class=yiv1492762737Apple-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=yiv1492762737Apple-style-span>90.71428571428571) </SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span>R =</SPAN>500000 <SPAN
style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-style-span> / 3562.359071428571260271</SPAN></DIV>
<DIV><SPAN style="FONT-FAMILY: arial, helvetica, sans-serif; FONT-SIZE: 13px"
class=yiv1492762737Apple-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=yiv1492762737Apple-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" rel=nofollow target=_blank>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" rel=nofollow target=_blank>http://wiki.osgeo.org/wiki/WMS_Tiling_Client_Recommendation</A><BR></PRE></DIV></DIV></DIV></DIV><BR><BR></DIV></DIV></DIV></BODY></HTML>