A tile server is a server that contains a collection of raster tile images. The tiles cover a given place on the earth. Tiles are organized in a row/column grid fashion. There are also multiple levels of tiles. Each level represents a different resolution of data, covering the same place on the earth. The level determines the number of tiles (number of rows and columns). As you zoom in or out, the level of data may change. As you pan around, the specific tiles that are needed may change. A collection of tiles forms a Tile Matrix having an exact bounding box. And a collection of multiple tile matrices forms a Tile Matrix Set that has an optional approximated bounding box.
MapInfo Pro provides a Web Map Tile Service (WMTS) client that retrieves tiled mapping data through your local Intranet or the Internet. The MapInfo Pro WMTS client provides opportunities for handling server specific details such as available number of zoom levels, map projections, image formats, and tile sizes.
This Web Map Tile Service (WMTS) client is based on standard specifications from the Open GIS Consortium (OGC) and provides a performance oriented and scalable service. A WMTS server achieves this by using image caching strategies to serve pre-rendered georeferenced map tiles. For more information about OpenGIS WMTS implementation standard, refer to: http://www.opengeospatial.org/standards/wmts.
A WMTS server can serve a single tile of a single layer of a map in one request. You cannot request a server to combine and return a map tile with information coming from more than one layer in a single fetching process. If you want multiple tiled map layers from the server, then you must made independent requests for each layer and then can combine or overlay the responses.
About Tile Server Tables and Map Layers
MapInfo Pro has a table for tile servers that consists of a TAB file and XML file. These files contain the information necessary to communicate with a tile server and retrieve tiles correctly. This information includes server URL, coordinate system and bounds, and other parameters for retrieving the proper tiles.
After opening a tile server table in MapInfo Pro, you can add it as a layer to a map. Tile server layers act as an underlying base map, so they are added to the bottom of the layer list by default. Tile server layers do not have attribute data, so they cannot be edited and labeled. They are meant to be used as backdrop images.
Tile Server Display Properties
Display properties can alter the appearance of the tiles returned from a tile server. Tile server images are rendered using the same display attributes as raster images. This includes:
- Translucency
- Transparency - on/off and transparent color
- Brightness
- Contrast
- Grayscale versus color
Tile Server Coordinate System and Reprojection
Tile server layers do not support raster image reprojection. This means that a map's coordinate system will be set to use the tile server coordinate system if a tile server layer is visible in a map. If the map displays tiles from two different tile servers in different projection systems, then MapInfo Pro uses the projection system of the tile that is most visible on the map.
You cannot change the map coordinate system when a map has an active tile server layer.