max zoom > 18

[incanus]

This was changed back in #178 but should:

1. Allow for zoom > 18
2. Allow for setting min/max from external API

[mb12]

The reason this limit is 18 is because max placement depth is 3 and maximum zoom for default mapbox tile source is 15. When doing placement, placement is done for the current zoom level plus placement depth. The placement depth is capped at 3 for highest zoom level in the SourceInfo.
You can verify this by placing a breakpoint in Collision::Collision and stepping through to verify how placementDepth is modified.

So increasing this value to higher than 18 without changing the placement algorithm would cause extremely sparse labels beyond 18. I would also recommend against simply changing placementDepth to higher than 3 would cause extreme slowdown in creating the SymbolBucket.

[donpark]

I'd recommend upping the maximum zoom level to 23 then either auto-hiding labels beyond zoom level 18 in code or in style.

[manuelwenner]

What about max zoom Level in mapbox-gl-native for android? When i try to set zoom level >18.0 it's ignored.

Thanks in advance for your answers.

[tmpsantos]

What about max zoom Level in mapbox-gl-native for android? When i try to set zoom level >18.0 it's ignored.

Thanks in advance for your answers

@manuelwenner It is currently hardcoded. Until we provide an API for that, you can tweak it at this variable here: https://github.com/mapbox/mapbox-gl-native/blob/master/src/mbgl/map/transform.hpp#L87

[manuelwenner]

Thanks @tmpsantos that worked perfect for me.

[petaren]

Is there an estimated time as to when an increase in max zoom level might be available? We would need a max zoom level of around 20 in my current project. Without it, it's unfortunately useless for us :(

[tmpsantos]

Is there an estimated time as to when an increase in max zoom level might be available? We would need a max zoom level of around 20 in my current project. Without it, it's unfortunately useless for us :(

Not on the roadmap AFAIK, but you can change that on the code for now.

[petaren]

Okey, L87 in transform.hpp is blank. So what do I need to change to get it to work?

[mourner]

It's hardcoded here now:

mapbox-gl-native/src/mbgl/map/transform_state.hpp

Lines 76 to 77 in e63fb44

	double min_scale = std::pow(2, 0);
	double max_scale = std::pow(2, 18);

I think we should address this issue sooner, shouldn't be hard and is an often requested feature.

[franckt]

Hi,
Any news about providing an api to set max zoom ?

[ansis]

@franckt max zoom is implemented in master and should be available in the next release

[bleege]

Re-opening as discussion with @kkaefer this morning revealed that the max zoom level in mgbl is actually 25.5. We'll need to update the iOS and Android bindings added in PR #3712 to support this.

/cc @mapbox/mobile

[bleege]

Capturing discussing with @1ec5 this afternoon where he confirmed that the 20 in transform_state.hpp is simply a default value and that if the bindings set a zoom higher (example 23) then Core GL will use and go to 23.

[bleege]

The new code in PR #3812 adds min and max zoom controls to Core GL so that all platforms will benefit. It also updated the values in the Android annotation warnings. The new values are:

MIN_ZOOM = 0.0
MAX_ZOOM = 25.5

[brunoabinader]

Possibly related: #4168 / #3644.