[OpenLayers-Users] UTM scales mismatch with Max/MinScaleDenomination

[Christopher Schmidt]

On Sun, Dec 02, 2007 at 09:08:04PM +0100, Andrea Aime wrote:
> Christopher Schmidt ha scritto:
> >On Sun, Dec 02, 2007 at 05:52:59PM +0100, Andrea Aime wrote:
> >>Hi Chris,
> >>about this scale inconsistency, you're right in saying it's due to the
> >>DPI. The WMS standard suggests a DPI of approximately 90 (well, a 
> >>multiplication factor of 0.28 in fact), and that's what GeoServer is 
> >>using to compute the scale.
> >>To be exactly true to the WMS standard (as far as I understand it) the 
> >>setting would have to be:
> >>
> >>OpenLayers.DOTS_PER_INCH = 25.4 / 0.28;
> >
> >I'm not sure where the 25.4 comes from
> 
> As far as I remember, it's the conversion between millimeters and inches
> (25.4 millimiters to make an inch).
> 

Interesting. So it's assuming a .28mm dot pitch or something like that.
Still not based in some kind of 'global' reality which is always true,
but at least it's not based on print :) 

Regards,
-- 
Christopher Schmidt
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