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Hi all, <div><br class="webkit-block-placeholder"></div><div>I'm building an application based on SharpMap, .Net based opensource GIS lib, which supports TileCache. It uses tilecache's capabilities document to get the available tilesets. In the capabilities document there's a list of resolutions, for instance:</div><div><a href="http://labs.metacarta.com/wms-c/Basic.py?LAYERS=sigma&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetCapabilities">http://labs.metacarta.com/wms-c/Basic.py?LAYERS=sigma&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetCapabilities</a></div><div><br class="webkit-block-placeholder"></div><div>contains</div><div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"><Resolutions></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">0.703125000 0.351562500 0.175781250 0.087890625 0.043945312 0.021972656 0.010986328 0.005493164 0.002746582 0.001373291 0.000686646 0.000343323 0.000171661 0.000085831 0.000042915 0.000021458 0.000010729 0.000005364 0.000002682 0.000001341</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"></Resolutions></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">for the boston-freemap-remote-mapserver layer.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">However if you would use these values you run into a problem at higher zoomlevels (14+ or so), since TileCache it self uses a more specific value:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">It says 0.000171661 whereas tilecache.py uses actually 0.000171661376953125 </div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">If you would use the advertised value you get an error:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">An error occurred: Current x value 4.876447 is too far from tile corner x 4.877930</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Which doesn't occur if you would use the more specific value.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">To me this sounds as a bug and TileCache should either use the advertised value or advertise the actual used value. Since right now it's not possible to use the capabilities document for WMS-C to access a cache properly.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Regards,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Steven</div></div></body></html>