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I'm new to GIS and confused by all the systems that are used to request data. Every provider seems to use a different system. What I need is to request an area between coordinates (WGS-84) as a picture. This is very easy by using bbox=...... in the URL on WMS-servers but those seem to be slow and rare.

Now I wanted to use bounding boxes (or similar) with WMTS (MapBox, Google Maps etc) but as far as I can see, the service doesn't support bounding boxes anymore.

Is there a way to simply get this functionality back? I'm using it in a program using C#, so if there is a library for this it would also do the job.

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Well, there is a OGC specification/ standard for Tile Services (WMTS), which states that you can use the requests GetCapabilities, GetTile and GetFeatureInfo (get it from here). So there's no GetMap-request using a BBOX for a WMTS (at least, if it's an OGC-compliant WMTS). It wouldn't make much sense as the service would need to crop tiles for you. I think major advantage of tile service is that you can cache tiles, because they always have the same extent.

But you can always use the GetCapabilities request if you want to see the details of the WMTS in your special case.

This is an example call for tiles: http://www.maps.bob/maps.cgi?service=WMTS&request=GetTile&version=1.0.0&layer=etopo2&style=default&format=image/png&TileMatrixSet=WholeWorld_CRS_84&TileMatrix=10m&TileRow=1&TileCol=3

It will need the parameters TileRow and TileCol to specify the Tiles you like to get. I dont know the spec in more detail, but I guess, TileMatrix will specifiy the resolution, you are looking for.

Maybe you can check with your provider, if they dont offer a WMS for the same data, too.

  • It seems, there is no other way than cropping the tiles in the program. The biggest problem is, to find the right tiles in the correct size for the area. I think I will stay with the WMS for now and keep things simple. Most of the libraries which offer the needed service are not compatible to my version of C# (limited to 3.5 due to Unity3D). Thanks anyway. :) – NagelAufnKopp Jan 28 '15 at 21:24

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