[OpenLayers-Dev] EPSG:41001

Gilbert, Antoine AGilbert at korem.com
Fri May 25 09:21:35 EDT 2007

Ok I finally made it, I had lot of errors, now it seems to be ok, my
tiles are fitting perfectly and the bounds passed to my getURL() method
are in 41001 format instead of long-lat.

As I was expecting I have some issues with labels and symbols (I was
figuring it before knowing openlayers). For example, one label rendered
in one tile but not displayed entirely in the tile may not fit with the
same label on the next tile, etc. etc.

Does this label problem is common with tile concept ? For example, if I
have a WMS layer tiled displaying lot of labels...


Here are my successful settings

var lon = -7929140;//-71.223;
var lat = 5880540;//46.8159;
var zoom = 1;
var map, layer;
function init(){
	map = new OpenLayers.Map("map", {maxExtent: new
OpenLayers.Bounds(-20037508.34, -20037508.34, 20037508.34, 20037508.34),
maxResolution: 31.25, minResolution: 0.625, numZoomLevels: 6, units:
'meters', projection: "EPSG:41001"});
	layer = new OpenLayers.Layer.PnsImage2( "OpenLayers PnsImage2", 
                        baseHREF+"ImageServlet", {layers: 'basic',
projection: "EPSG:41001"});
	map.setCenter(new OpenLayers.LonLat(lon, lat), zoom);
	map.addControl( new OpenLayers.Control.PanZoomBar() );

-----Original Message-----
From: Christopher Schmidt [mailto:crschmidt at metacarta.com] 
Sent: 24 mai 2007 11:18
To: Gilbert, Antoine
Cc: dev at openlayers.org; Houde, Jonathan
Subject: Re: [OpenLayers-Dev] EPSG:41001

On Thu, May 24, 2007 at 11:07:56AM -0400, Gilbert, Antoine wrote:
> For example a tile 256x256 is assumed to have long lat ratio 1x1, but
> a map using 41001 this long lat ratio does not make a square. That's
> I don't understand the 1x1 concept

> Here is an example of URL I build with the bounds
> t=256&bbox=-71.267246,46.846768,-71.25626,46.857754
> Here is my javascript/html

You didn't set your resolution. maxResolution should be set to something
sane for the projection you are using, like 156543 .

Christopher Schmidt

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