Vector Tilemap


This resource is optional.

The tilemap resource describes a quadtree of tiles and can be used to avoid requesting for tiles that don't exist in server. Each node of the tree has an associated tile. The root node (lod 0) covers the entire extent of the data. Children are identified by their position with NW, NE, SW, SE. Tiles are identified by lod/h/v, where h and v are indexes on a 2^lod by 2^lod grid . Those values are derived by the position in the tree. The tree has a variable depth. A node doesn’t have children if the complexity of the data in the associated tile is below some threshold. This threshold is based on a combination of number of features, attributes and vertices. .

Example Usage

Note: This is an example URL only and is not an active link to an existing attachment.

JSON Response Syntax


Where <node> is : [<node>,<node>,<node>,<node>] in order NW,NE,SW,SE with possible values:

1 // tile with no children (referred to as a leaf tile)

0 // no tile (because there's no data here so the tile file does not exist)

2 // sub tree defined in a different index file (to mitigate the index being too big)

JSON Response Example