[Mapcss] Zoom levels: bad idea?

[Sebastian Klein]

Chris Browet wrote:
> Unless I'm mistaken, I understand the zoom level (as in "way|z1-11") as
> "OSM TMS zoom level", right?
> 
> What about maps rendered in another projection than mercator/google,
> e.g. OSGB36, which is non-othogonal ?
> How is the implementation supposed to deduce the zoom level based upon a
> pixels per meters zoom level?
> 
> Extreme, but I tend to think the zoom level namespace selector should be
> dropped altogether in favor of the "way|s5000" indicated as example in
> the specs, which is far more explicit.
> 
> While, if needed, going to zoom level from a scale in the context of a
> mercator projection is easy for the implementation, I don't see how to
> go from zoom level to scale consistently for "exotic" projections, given
> the restrictive (assumed) definition of the zoom levels...

Generally I like the zoom levels because they provide a handy
logarithmic scale.

I think for Kothic it is convenient to use the standard slippy map /
google-mercartor tile scheme to map the zoom level.

But I see no reason it has to be the same for all renderers. I will just use

  s = s_0 / 2^z

with an arbitrary scale s_0.


Sebastian