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tilematrix.md

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tilematrix

The two base classes are TilePyramid which defines tile matrices in various zoom levels and its members, theTile objects. TilePyramid

TilePyramid

TilePyramid(grid_definition, tile_size=256)

  • grid_definition: Either one of the predefined grids (geodetic or mercator) or a custom grid definition in form of a dictionary. For example:

    {
    "shape": (1, 1),
    "bounds": (2426378.0132, 1528101.2618, 6293974.6215, 5395697.8701),
    "is_global": False,
    "epsg": 3035
}
    • shape (height, width): Indicates the number of tiles per column and row at zoom level 0.
    • bounds (left, bottom, right, top): Units are CRS units.

    Please note that the aspect ratios of shape and bounds have to be the same.

    • Alternatively to epsg, a custom proj string can be used:
    "proj": """
    +proj=ortho
    +lat_0=-90
    +lon_0=0
    +x_0=0
    +y_0=0
    +ellps=WGS84
    +units=m +no_defs
"""
    • is_global: Indicates whether the grid covers the whole globe or just a region.

  • tile_size: Optional, specifies the target resolution of each tile (i.e. each tile will have 256x256 px). Default is 256.

Variables

  • type: The projection it was initialized with (geodetic, mercator or custom).
  • tile_size: The pixelsize per tile it was initialized with (default 256).
  • left: Left boundary of tile matrix.
  • top: Top boundary of tile matrix.
  • right : Right boundary of tile matrix.
  • bottom : Bottom boundary of tile matrix.
  • x_size: Horizontal size of tile matrix in map coordinates.
  • y_size: Vertical size of tile matrix in map coordinates.
  • crs: rasterio.crs.CRS() object.
  • srid: Spatial reference ID (EPSG code) if available, else None.

Methods

Matrix properties

  • matrix_width(zoom): Returns the number of columns in the current tile matrix.
    • zoom: Zoom level.
  • matrix_height(zoom): Returns the number of rows in the current tile matrix.
    • zoom: Zoom level.

Geometry

  • tile_x_size(zoom): Returns a float, indicating the width of each tile at this zoom level in TilePyramid CRS units.
    • zoom: Zoom level.
  • tile_y_size(zoom): Returns a floats, indicating the height of each tile at this zoom level in TilePyramid CRS units.
    • zoom: Zoom level.
  • pixel_x_size(zoom): Returns a float, indicating the vertical pixel size in TilePyramid CRS units.
    • zoom: Zoom level.
  • pixel_y_size(zoom): Returns a float, indicating the horizontal pixel size in TilePyramid CRS units.
    • zoom: Zoom level.
  • top_left_tile_coords(zoom, row, col): Returns a tuple of two floats, indicating the top left coordinates of the given tile.
    • zoom: Zoom level.
    • row: Row in TilePyramid.
    • col: Column in TilePyramid.
  • tile_bounds(zoom, row, col, pixelbuffer=None): Returns left, bottom, right, top coordinates of given tile.
    • zoom: Zoom level.
    • row: Row in TilePyramid.
    • col: Column in TilePyramid.
    • pixelbuffer: Optional buffer around tile boundaries in pixels.
  • tile_bbox(zoom, row, col, pixelbuffer=None): Returns the bounding box for given tile as a Polygon.
    • zoom: Zoom level.
    • row: Row in TilePyramid.
    • col: Column in TilePyramid.
    • pixelbuffer: Optional buffer around tile boundaries in pixels.

Tiles

  • intersecting(tile): Return all tiles intersecting with tile. This helps translating between TilePyramids with different metatiling settings.
    • tile: Tile object.
  • tiles_from_bbox(geometry, zoom): Returns tiles intersecting with the given bounding box at given zoom level.
    • geometry: Must be a Polygon object.
    • zoom: Zoom level.
  • tiles_from_geom(geometry, zoom): Returns tiles intersecting with the given geometry at given zoom level.
    • geometry: Must be one out of Polygon, MultiPolygon, LineString, MultiLineString, Point, MultiPoint.
    • zoom: Zoom level.

Tile

Tile(tile_pyramid, zoom, row, col)
  • tile_pyramid: A TilePyramid this Tile belongs to.
  • zoom: Tile zoom level.
  • row: Tile row.
  • col: Tile column.

Variables

After initializing, the object has the following properties:

  • tile_pyramid or tp: TilePyramid this Tile belongs to.
  • crs: rasterio.crs.CRS() object.
  • srid: Spatial reference ID (EPSG code) if available, else None.
  • zoom: Zoom.
  • row: Row.
  • col: Col.
  • x_size: Horizontal size in SRID units.
  • y_size: Vertical size in SRID units.
  • index or id: Tuple of (zoom, col, row)
  • pixel_x_size: Horizontal pixel size in SRID units.
  • pixel_y_size: Vertical pixel size in SRID units.
  • left: Left coordinate.
  • top: Top coordinate.
  • right: Right coordinate.
  • bottom: Bottom coordinate.
  • width: Horizontal size in pixels.
  • height: Vertical size in pixels.

Methods

Get other Tiles

  • get_parent(): Returns parent Tile.
  • get_children(): Returns children Tiles.
  • get_neighbors(connectedness=8): Returns a maximum of 8 valid neighbor Tiles.
    • connectedness: 4 or 8. Direct neighbors (up to 4) or corner neighbors (up to 8).
  • intersecting(TilePyramid): Return all tiles from other TilePyramid intersecting with tile. This helps translating between TilePyramids with different metatiling settings.
    • tilepyramid: TilePyramid object.

Geometry

  • bounds(pixelbuffer=0): Returns a tuple of (left, bottom, right, top) coordinates.
    • pixelbuffer: Optional buffer around tile boundaries in pixels.
  • bbox(pixelbuffer=0): Returns a Polygon geometry.
    • pixelbuffer: Optional buffer around tile boundaries in pixels.
  • affine(pixelbuffer=0): Returns an Affine object.
    • pixelbuffer: Optional buffer around tile boundaries in pixels.

Other

  • shape(pixelbuffer=0): Returns a tuple with (height, width).
    • pixelbuffer: Optional buffer around tile boundaries in pixels.
  • is_valid(): Returns True if tile ID is valid in this tile matrix and False if it isn't.