Warning: Zoom level 19,20,21 not reachable is not reliable

[andrewharvey]

Some sources only have tiles at higher zooms in some regions of the map so it depends where you test, without knowing exactly where has the higher zoom level tiles this warning does spit false positives sometimes.

[rbuffat]

This is an excellent point. I'm currently unsure how a reliable test could look like. As far as I'm aware there is no way to check if any tiles on a zoom level exist, without testing for the existence of existing tiles.

[andrewharvey]

I'm not sure if it's going to be possible to have a reliable test for this.

[rbuffat]

As a workaround I changed the warning message as follows:

Warning: Zoom level 19,20,21 not reachable. (Tested: 1,18,19,20,21) Tiles might not be present at tested location: 146.42808179588013,-33.10596125

Would you keep the warning like this, or just leave it out?