[OpenLayers-Users] Bounds / Projection

[Bill Thoen]

eoinyp wrote:
> But Im still stuck as to how to set the map to focus on Ireland. I dont
> understand how to define the bounds of a suitable box. Can you give me any
> pointers there

If your table is in the Google projection already, then you can use 
ogrinfo to dump out the extents in the right format. Otherwise just 
declare the map to have extents well beyond the limits of the Google 
projection, add a MousePosition control and then zoom in on the Emerald 
Isle and note its bounds. A third thing you can do is follow Bret 
Taylor;s (of Google) suggestion below to go look up the info on the 
Mercator projection to get the world bounds of that, then you can 
calculate the Google coordinates using ratios between those limits and 
your lat/lon coordinates:

> From: Bret Taylor <btay... at google.com>
> Date: Fri, 1 Jul 2005 15:49:38 -0700
> Subject: Re: What type of map projection does Google use for Google Maps
>
> We use the Mercator projection for our maps. Wolfram MathWorld has a good
> page on the projection (and a bunch of other map projections):
>
> http://mathworld.wolfram.com/MercatorProjection.html
- Bill Thoen