VectorReaderIter

Added in version 1.2.

class VectorReaderIter(**properties: Any)

Superclasses: Object

Reads the layers and features of a vector tile.

To create a new VectorReaderIter, use iterate.

A vector tile consists of named layers, which contain features. Each feature has an ID, a geometry, and a set of key/value tags. The meanings of the IDs and tags depends on the data source that the tile came from. The OpenMapTiles schema is a common schema for vector tiles.

To read all layers in a tile, use get_layer_count and read_layer. If you know the name of the layer you want, you can also use read_layer_by_name. Once the iterator is reading a layer, you can call next_feature in a loop to read all the features in the layer.

A VectorReaderIter is not thread-safe, but iterators created from the same VectorReader can be used in different threads.

See the Mapbox Vector Tile specification for more information about the vector tile format.

Methods

class VectorReaderIter

feature_contains_point(x: float, y: float) → bool

Determines whether the current feature contains the given point.

The point must be specified in tile space. See get_layer_extent to get the range of the coordinates.

Only polygon or multipolygon features can contain a point. For all other feature types, this function returns False.

If the point is on the border of the polygon, this function may return either True or False.

Added in version 1.2.

Parameters:

• x

• y

get_feature_geometry_type() → GeometryType

Gets the geometry type of the current feature.

Added in version 1.2.

get_feature_id() → int

Gets the ID of the current feature.

Added in version 1.2.

get_feature_keys() → list[str]

Gets the keys of the tags of the current feature.

Added in version 1.2.

get_feature_point() → Tuple[bool, float, float]

Gets the coordinates of the current feature in tile space, if the feature is a single point.

See get_layer_extent to get the range of the coordinates.

It is an error to call this function if the feature is not a single point. Use get_feature_geometry_type to check the feature’s geometry type.

Added in version 1.2.

get_feature_tag(key: str) → Tuple[bool, Value]

Gets the value of the tag with the given key.

Added in version 1.2.

Parameters:

key – The key of the tag to get.

get_layer_count() → int

Gets the number of layers in the vector tile.

Added in version 1.2.

get_layer_extent() → int

Gets the extent for coordinates in the current layer.

0 represents the top and left edges of the tile, and this value represents the bottom and right edges. Feature geometries may extend outside of this range, since tiles often include some margin.

Tiles do not contain metadata about the location of the tile within the world, so it is up to the caller to know the tile’s coordinates and convert latitude/longitude to tile-space coordinates.

Added in version 1.2.

get_layer_feature_count() → int

Gets the number of features in the current layer.

You can loop over all features in the current layer by calling read_feature with each index from 0 to the feature count, but it might be easier to use next_feature instead.

Added in version 1.2.

get_layer_name() → str

Gets the name of the current layer.

Added in version 1.2.

get_reader() → VectorReader

Gets the reader that the iterator is iterating over.

Added in version 1.2.

next_feature() → bool

Advances the iterator to the next feature in the current layer.

Added in version 1.2.

read_feature(index: int) → None

Moves the iterator to the feature at the given index in the current layer.

You can get the number of features in the current layer with get_layer_feature_count.

Added in version 1.2.

Parameters:

index – The index of the feature to read.

read_layer(index: int) → None

Sets the current layer of the reader to the layer at the given index.

Added in version 1.2.

Parameters:

index – The index of the layer to read.

read_layer_by_name(name: str) → bool

Moves the iterator to the layer with the given name, if present.

If the layer is not found, the current layer will be set to None and the function will return False. Layers are typically omitted if they are empty, so don’t assume that a layer in the schema will always be present.

The iterator’s current feature will be None after calling this function; use next_feature to advance to the first feature in the layer.

Added in version 1.2.

Parameters:

name

Properties

class VectorReaderIter

props.reader: VectorReader

The type of the None singleton.