Re: Worldmap mercator projection - Latitude to Y calculation.

J.P. ,

First off, FYI, Paul has minimized his posting about the subject to the 
Win10 group only.  If you're not there already it might be a good idea to 
take a peek.

> If it _is_ light-source-at-centre, then the Y co-ordinate would just be
> the tangent of the latitude

Somewhere along the road I had a similar thought.   But why than do all the 
formules I now have (four at the moment) all do a tan() and than wrap that 
up in a log() ?    There must be something to it.

Regards,
Rudy Wieser