get
Given a location and a grid size it creates either a 2x2 or a 3x3 grid of tiles (VectorTiles) to cover that location.
Return
A TileGrid object which contains a MutableList of VectorTiles representing the grid along with a BoundingBox around the center of the grid. When the location leaves that BoundingBox a new grid is required.
Parameters
current
The current location of the device.