A WMS layer streams map imagery straight from an external server — a government basemap, a partner's service, your own GeoServer — without copying any data into Tamaat. The service stays the source of truth.
Older services work too, including the long-running government endpoints that still publish an earlier version of the standard.
Connect a service
- Open the project menu in the layer explorer and choose "Add Layer".
- Switch to the "Service" tab. The type is "WMS (Web Map Service)".
- Paste the service URL — either the bare endpoint or a full GetMap URL — and press "Inspect".
Tamaat fetches the service's capabilities document and shows what it found: the service title, its WMS version, and every published layer with its description and supported coordinate systems.
A few things to know at this step:
- Composite service maps. Many services publish a root layer that draws the whole map in one request (marked "Composite service map"). It is pre-selected by default — the fastest way to get the full service on your map.
- Pick specific layers instead when you only want part of the service — for example only the Hydrography layer from a topographic service. Use "Select all" and "Reset" to manage the list quickly.
- Layers that cannot serve Web Mercator directly are flagged; Tamaat requests the closest supported projection and notes the difference.
Press "Add layer". The service appears in the layer explorer as a single raster layer named after the service, with an "Online" status chip and an expandable list of the service's published sublayers.
Requests go through your workspace rather than from your browser to the remote server, so services that block direct browser requests still work, and your collaborators reach the layer through their own Tamaat session.
Manage a connected service
Open the layer's Labels & Symbols dialog. A WMS layer gets two tabs instead of vector styling: "Display" and "Source".
On "Display", Display Mode switches between "Full List" (the service's full map) and "Custom List" (only the layers you tick), so one connected service behaves like a small stack of toggleable sublayers. Auto-refresh keeps up with services whose imagery changes underneath you — weather, traffic, live sensors — "Every map load" or on a custom cadence.
On "Source", the "Connection" section shows Status (whether the service answered last time it was checked) and when it was last checked and refreshed. "Refresh" re-reads the service now, which is what you want after a provider changes what they publish.
Visibility behaves like any other layer
The explorer's visibility eye, opacity, and layer ordering all apply to the WMS layer as a whole. Put reference imagery under your working layers and drop its opacity so your own data stays legible on top of it.
When the service misbehaves
- "The remote WMS service returned an unreadable capabilities document" —
the URL answered, but not with WMS capabilities. Check that the URL is the
service endpoint (often ending in
/wms) rather than a viewer page. - Timeouts — many public services require HTTPS; try the same address with
https://. - A legacy NRCan Toporama address — the old
wms.ess-ws.nrcan.gc.cahost is retired; usehttps://maps.geogratis.gc.ca/wms/toporama_eninstead. Tamaat suggests the current URL when it recognizes the legacy one. - Layers stopped drawing after the provider changed their service — press "Refresh" on the "Source" tab to re-read capabilities, then re-check the layers you need in the "Custom List".