[MapProxy] Confused about zoom levels when proxying Google Maps

[Oliver Tonnhofer]

Hi,

On 28.07.2014, at 12:32, Paul William wrote:
> I am using MapProxy to proxy Google Maps into an application that supports WMS servers.

Google does not permit that. 

> I am new at GIS software and confused by the zoom levels. For some reason, the MapProxy WMS server only serves up tiles to a maximum of Google's zoom level 17. If I use MapProxy Seed tool, I can cache tiles at a maximum of 19 (confirmed by look at the images in the cache).

A request to http://localhost:8080/service?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&BBOX=13.14797258431889126,52.41603517514587907,13.29055343492096775,52.51031994521477486&SRS=EPSG:4326&WIDTH=1792&HEIGHT=1185&LAYERS=gh_layer&STYLES=&FORMAT=image/png&DPI=72&MAP_RESOLUTION=72&FORMAT_OPTIONS=dpi:72&TRANSPARENT=TRUE

makes requests to http://mt1.google.com/vt/lyrs=y&x=281376&y=172134&z=19, so that looks right.


> I cannot zoom in as far as the data, regardless of what client I use. The MapProxy Demo (OpenLayers?) client has the same restriction.

The demo client is limited and it is not configured automatically to use the right number of zoom levels.

Regards,
Oliver

-- 
Oliver Tonnhofer    | Omniscale GmbH & Co KG    | http://omniscale.com
http://mapproxy.org | https://github.com/olt    | @oltonn