[OSGeo-Standards] Handling of resolution (or scale?) in WMSC

[Jody Garnett]

I hope this one will be a bit quicker; and not push quite so many buttons.

I would like confirmation on how TileCache and/or GeoWebCache is 
calculating the resolutions they return as part of their 
Capabilities/VendorSpecificParameters/TileSet information.

In particular ...
- WMS calculates scale information based on an assumption of 90 DPI; and 
the size of the center pixel in a GetMap request
- My customer has found that they need to make an assumption of 103 DPI 
(when converting between GWC resolution and scale) for central Europe

My guess is the resolutions are calculated at the center of the tile 
set; according to WMS GetMap conventions; the fact that the resolution 
to scale calculation is off as we move north is just a reflection of how 
the WMS GetMap scale changes as you pan around ...

I would like to confirm this; and once again tighten up our wiki page 
description.

Jody