Scale ratio in print tool / map window

[SannaJokela]

Is it possible to have scale ratio info also in print tool and at the same time also in the map window? Like 1:250 000 (This was suggested in Oskari Joint Development Forum)

[ZakarFin]

It's possible to include yes. Someone just needs to implement it.

[jampukka]

What is the use case here? Taking a ruler and measuring stuff from the screen will not yield correct results (it might in some single case, but change your resolution and it will not anymore). For PDF printouts it does make some sense (since PDF is fixed at 72DPI) but the scale denominator will only be correct when actually printed out (not when viewed on screen). Also the zoom levels rarely correspond to any exact scale denominator, so you will end up with arbitrary scale ratios of for example 1:1521.541. Is that useful information?

Also, scale calculations will work super poorly in small scales in projections with heavy distortion in high up north (for example in EPSG:4326 used in demo.oskari.org or WebMercator).

[SannaJokela]

True. This was my thoughts also. In my opinion the scalebar should be enough. With GIS software it is possible to have scales and play around with them, e.g. you need to print your map layout with scale of 1:25 000 > this would be probably the use case.

[ZakarFin]

So basically this would mean more work than it's probably worth to be useful for anyone. Close as "won't fix"?

[jampukka]

If the wanted feature is to be able to print PDFs in certain exact scales (1:25 000 etc) then that's a different beast than just adding scale ratio information.

That feature would be a bit problematic as well. The same projection stuff applies here as well. Also the map might look different than you expect because WMS layers typically have different styles applied to them based on scale limits.

[ZakarFin]

There's something related to this included in 1.48.0 in oskariorg/oskari-frontend#437 and oskariorg/oskari-server#235. Not sure if this is what you were after, but you should check it out.

[ZakarFin]

No-one seems too exited to develop this so closing the issue.