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That's essentially how the UK does motorway junctions. Lanes go to different places, road signs a few miles in advance and written in white on the lanes. Genera
by JonChesterfield 3y ago
That's essentially how the UK does motorway junctions. Lanes go to different places, road signs a few miles in advance and written in white on the lanes. Generally we don't bother with the U turn options as relatively few people want to go in the opposite direction.
If it looks like magic, your country is doing this wrong.
Benefits of said junction include noone needing to slow down. Drawbacks include some fraction of people accidentally going in a direction they didn't want, using quite a lot of land, general construction cost.
- bdjsiqoocwk 3y agoIt's a roundabout.
- JonChesterfield 3y agoI don't think so. Different fairness properties. A roundabout has conventions for who has priority on enter/exit which means one of the lanes waits for a space in the other. Motorway junctions and this example have the joining lane separate from the existing one so either can block the other. Note that high traffic roundabouts usually end up with traffic lights to force a degree of fairness, where relative flow rate can be adjusted by different timing on the lights. It's the difference between enforcing mutual exclusion by control flow vs a futex.