Make max_zoom part of the struct (#52)

* Make max_zoom part of the struct

This allows to set the maximal zoom level that is downloaded as a keyword argument during Map construction.
This is useful, when the TileProvider has different zoom levels for different parts of the world.
Using the max_zoom level of the provider would therefore lead to multiple download errors.

* remove show

---------

Co-authored-by: Simon <[email protected]>

src/Tyler.jl

@@ -67,6 +67,7 @@ struct Map
     depth::Int
     halo::Float64
     scale::Float64
+    max_zoom::Int
 end
 
 # Wait for all tiles to be loaded
@@ -101,7 +102,8 @@ function Map(extent, extent_crs=wgs84;
     cache_size_gb=5,
     depth=8,
     halo=0.2,
-    scale=1.0
+    scale=1.0,
+    max_zoom=TileProviders.max_zoom(provider)
 )
 
     fetched_tiles = LRU{Tile, Matrix{RGB{N0f8}}}(; maxsize=cache_size_gb * 10^9, by=Base.sizeof)
@@ -135,7 +137,7 @@ function Map(extent, extent_crs=wgs84;
         max_parallel_downloads, OrderedSet{Tile}(),
         tiles_being_added, downloaded_tiles,
         display_task, download_task, screen,
-        depth, halo, scale
+        depth, halo, scale, max_zoom
     )
     tyler.zoom[] = get_zoom(tyler, extent)
     download_task[] = @async begin
@@ -298,7 +300,7 @@ function queue_tile!(tyler::Map, tile)
     end
 end
 
-TileProviders.max_zoom(tyler::Map) = Int(max_zoom(tyler.provider))
+TileProviders.max_zoom(tyler::Map) = tyler.max_zoom
 TileProviders.min_zoom(tyler::Map) = Int(min_zoom(tyler.provider))
 
 function get_zoom(tyler::Map, area)