a-b-street / abstreet

Transportation planning and traffic simulation software for creating cities friendlier to walking, biking, and public transit
https://a-b-street.github.io/docs/
Apache License 2.0
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Design LTN tool: Improve isolated cell detection #1111

Open andrewphilipsmith opened 10 months ago

andrewphilipsmith commented 10 months ago

Current behaviour:

When placing modal filters on, the tool will warn the user if the filters create a cell which is unreachable by car).

When adjusting one-way streets or turn restrictions, no equivalent warning is given if the edits create an unreachable cell.

Example

https://github.com/a-b-street/abstreet/assets/5346065/4e032804-f28e-4199-b0d7-c37733a4221a

Video shows current behaviour while editing Demesne Fuze in Oxford

Suggested improvement:

The procedure for detecting unreachable cells should be improved to account for oneway street and turn restrictions. This should apply both when importing OSM data and when editing in the LTN tool.