Data Import

The Data Import panel is the entry point of the City2Graph pipeline. It acquires urban feature layers from the shared feature selector, plus GTFS transit feeds, and materializes them as Blender objects every other panel can consume.

At the very top, an Overture API Key badge shows whether a production key is configured (Set) or the bundled DEMO key is in use. With the demo key the Overture endpoints are rate-limited and may cap results; the gear icon opens the add-on preferences to paste your own key.

Step 1 — Define Area

Choose how to bound the data download. The methods mirror the OSMnx tab so the same workflow works with or without an imported graph.

Method Description
From OSMnx Graph Use the active OSMnx graph’s bounding box and projection. A badge confirms which graph is used, or warns if none is active.
By Place Name Geocode a place (e.g. Burjassot, Valencia, Spain); set the Geocoder Result # to disambiguate.
By Coordinates A bounding box around a Latitude/Longitude plus a Radius (m).
By Address Geocode a postal address plus a Radius (m).
By Bounding Box Manual North / South / East / West bounds.
From Object Polygon Use the bounds of a selected Blender mesh object.
Note

If you pick a non-OSMnx method while an OSMnx graph is active, a hint confirms that the outputs will still be aligned with that graph’s coordinate space.

Step 2 — Feature Source & Tags

Choose one feature source, one feature preset or a custom OSM tag expression, and the maximum number of features to request.

Control Description
Source Overture / City2Graph or OSMnx / Overpass. The Feature list adapts to the source: Overture only lists what its API serves (buildings, places, segments, water, land, and the POI presets that filter the places layer), while OSMnx lists every preset plus Custom Tags.
Feature Feature preset for the selected source. Custom OSM tags are available only in OSMnx mode.
Tags Shown for Custom Tags; enter comma-separated OSM key=value pairs such as amenity=restaurant or building=yes.
Max Features Upper bound where the selected source supports limiting. Values above ~15 000 may be slow or capped server-side (a warning appears).
Nodes Only OSMnx source only: keep just node elements (exclude ways/relations), matching the notebook point-feature workflow.
Note

With Source = OSMnx and Area Method = By Place Name, features are queried within the place’s administrative polygon (features_from_place), so counts match ox.features_from_place(...). Other area methods use the bounding box, which returns more features because it is a rectangle around the area.

The Overture source maps presets to the closest available layer:

  • Buildings → Overture buildings.
  • Amenity → Overture places (all POIs, unfiltered).
  • Restaurant / Shop / Health / Education / Leisure / Parking / … → Overture places filtered by matching category keywords, so each preset returns a distinct subset rather than the full place list.
  • Highway → OSMnx street segments.
  • Water / Land / Natural / Park → OSMnx fallback layers.
  • Custom Tags → OSMnx, because Overture does not support arbitrary OSM tags.
Note

Overture’s place taxonomy differs from OpenStreetMap tags, so counts will not match an OSMnx {"amenity": ...} query. For OSM-tag-exact results, switch the Source to OSMnx / Overpass.

Step 3 — Download

Control Description
Get as Polygons Download features keeping their native polygon/line geometry.
Get as Points Download as points: Places arrive natively as points; other types are reduced to representative centroids.
Convert Selected to Centroids Create a point-only sibling object from the active polygon/line mesh (the original is kept).
Tip

For point-based analyses (proximity graphs, metapaths) either use Get as Points or convert an existing polygon object to centroids.

Local File (GeoJSON / Shapefile)

Load from File imports a GeoJSON or Shapefile directly, aligning it with the active OSMnx graph when present. Use this when you already have local data.

Process Segments

Prepares a raw segment object for graph construction (splitting by connectors and extracting barriers). Select the segment object — and optionally also a connectors object — then run Process Segments.

GTFS Transit Data

Control Description
GTFS File Path to a GTFS .zip feed.
Import GTFS Loads the feed; a badge then reports how many tables were parsed.
Create Stops / Create Routes Once loaded, choose what to visualize.
Stop Size Size of the stop sphere visualizations.
Visualize GTFS Builds the stop/route objects in the viewport.

A loaded feed unlocks the Transportation panel.

Step-by-step tutorial

For a worked example using Burjassot, follow Import urban data.

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