XYZ¶
A pre-tiled image layer that uses a generic template URL to access raster tiles.
An XYZ layer exposes no metadata, so the user is resposible for telling osgEarth about the profile
and other aspects of the data source.
The URL template MUST include the template parameters {z} (specifying the tile level), and {x} and {y} (specifying the tile offset within the level). The {y} parameter also suppose a unary negative in the form {-y} since it’s common to see datasets that are flipped in the vertical direction.
XYZImage, XYZElevation¶
CLASS: XYZImageLayer (inherits from ImageLayer)
CLASS: XYZElevationLayer (inherits from ElevationLayer)
Property | Description | Type | Default |
---|---|---|---|
url | Location of data source (local or remote), including templated parameters {x}, {y}/{-y}, and {z} (see example). The template also supports round-robin characters by way of square brackets ([]). | URI | |
profile | Tiling configuration of the data source (typically global-geodetic or spherical-mercator ) |
string | global-geodetic |
Examples¶
In this example, the template URL contains both an optional “round-robin” character set and the required z/x/y tile parameters. The round-robin set will cycle between three servers that balance the load of the requests:
a.tile.openstreetmap.org
b.tile.openstreetmap.org
c.tile.openstreetmap.org
osgEarth will fill in the x/y/z parameters based on the current tile request during run-time.
<XYZImage name="OSM Vector Map">
<url>http://[abc].tile.openstreetmap.org/{z}/{x}/{y}.png</url>
<profile>spherical-mercator</profile>
<attribution>©OpenStreetMap contributors</attribution>
</XYZImage>