Custom layers¶
Custom deck.gl layers are available in pydeck, loaded dynamically.
Layers are loaded dynamically by the frontend, when the output from
pydeck.bindings.deck.Deck.show()
or pydeck.bindings.deck.Deck.to_html()
is called and loaded.
Custom layers must subclass deck.gl’s Layer or CompositeLayer classes. They must also include deck.gl and @deck.gl/layers as external libraries in the webpack config. You can see this repo for a minimal example.
Code for usage of that example layer can be seen here:
"""
CustomLayer
===========
A custom layer named LabeledGeoJsonLayer copied from this Observable Notebook for use in pydeck:
https://observablehq.com/@pessimistress/deck-gl-custom-layer-tutorial
Registering a custom layer requires some knowledge of JavaScript and bundling.
See https://github.com/ajduberstein/pydeck_custom_layer for a minimal example layer.
"""
import pydeck
pydeck.settings.custom_libraries = [
{
"libraryName": "LabeledGeoJsonLayerLibrary",
"resourceUri": "https://unpkg.com/pydeck-custom-layer-demo/dist/bundle.js",
}
]
DATA_URL = "https://raw.githubusercontent.com/johan/world.geo.json/master/countries.geo.json"
custom_layer = pydeck.Layer(
"LabeledGeoJsonLayer",
data=DATA_URL,
filled=False,
billboard=False,
get_line_color=[180, 180, 180],
get_label="properties.name",
get_label_size=200000,
get_label_color=[0, 255, 255],
label_size_units=pydeck.types.String("meters"),
line_width_min_pixels=1,
)
view_state = pydeck.ViewState(latitude=0, longitude=0, zoom=1)
r = pydeck.Deck(custom_layer, initial_view_state=view_state, map_provider=None)
r.to_html("custom_layer.html", css_background_color="#333")
