Class MetaGrid

Parameters:

• grid - the grid to use for the metatiles
• meta_size ((x_size, y_size)) - the number of tiles a metatile consist
• meta_buffer (pixel) - the buffer size in pixel that is added to each metatile. the number is added to all four borders. this buffer may improve the handling of lables overlapping (meta)tile borders.

Overrides: object.__init__

(inherited documentation)

Returns the bbox of the metatile that contains tile_coord.

>>> mgrid = MetaGrid(grid=TileGrid(), meta_size=(2, 2))
>>> [round(x, 2) for x in mgrid.meta_bbox((0, 0, 2))]
[-20037508.34, -20037508.34, 0.0, 0.0]
>>> mgrid = MetaGrid(grid=TileGrid(), meta_size=(2, 2))
>>> [round(x, 2) for x in mgrid.meta_bbox((0, 0, 0))]
[-20037508.34, -20037508.34, 20037508.34, 20037508.34]

Parameters:

• tile_coord ((x, y, z))

Returns all tiles that belong to the same metatile as tile_coord. The result contains for each tile the tile_coord and the upper-left pixel coordinate of the tile in the meta tile image.

>>> mgrid = MetaGrid(grid=TileGrid(), meta_size=(2, 2))
>>> tiles = list(mgrid.tiles((0, 1, 1)))
>>> tiles[0], tiles[-1]
(((0, 1, 1), (0, 0)), ((1, 0, 1), (256, 256)))
>>> list(mgrid.tiles((0, 0, 0)))
[((0, 0, 0), (0, 0))]

Returns the size of a metatile (includes meta_buffer if present).

>>> mgrid = MetaGrid(grid=TileGrid(), meta_size=(2, 2), meta_buffer=10)
>>> mgrid.tile_size(2)
(532, 532)
>>> mgrid.tile_size(0)
(256, 256)

Parameters:

• level - the zoom level

Get a list with all affected tiles for a bbox in the given level.

>>> grid = MetaGrid(TileGrid(), (2, 2))
>>> bbox = (-20037508.34, -20037508.34, 20037508.34, 20037508.34)
>>> grid.get_affected_level_tiles(bbox, 0)
... #doctest: +NORMALIZE_WHITESPACE +ELLIPSIS
((-20037508.342789244, -20037508.342789244,          20037508.342789244, 20037508.342789244), (1, 1),          <generator object ...>)

Returns: bbox, (xs, yz), [(x, y, z), ...]

the bbox, the size and a list with tile coordinates, sorted row-wise