Directions not routing through bridge

The directions refuse to navigate over this bridge for a car but I’m not sure why. Could it be that the width of the road is 2 and the car profile is 2m wide so it won’t cross it?

Hi Sam,

What happens if you comment the line “restrictedValues.add(“no”);” part out of the CarFlagEncoder.java. Does it still refuse to route over the bridge?

This is just a test to see if the bridge has a “no pass” tag.

I think @Sam_Ruston refers to our hosted API where we use a width of 2m for car and add a tiny offset of 5cm so that 2m is not passable. Probably we added this offset as the width tag is often not measured (as opposed to a legal limit like maxwidth=2) and just guessed from the mapper. (A legal limit of 2m would be passable as it does not include mirrors etc.)

With some ground truth information you could change this to maxwidth=2. We could also change our car width to a smaller value but it is assumed with mirrors so 2m seems to be reasonable.

Gotcha, thanks! Thought that might be the case. Looking on Street View that bridge is sufficiently large for cars and it even shows small trucks driving across it with a fair amount of room. I’ll report a change on OSM as it seems to be bad OSM data in this case.

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Hi,

We’ve found another example of this happening: OpenStreetMap

The passage is pretty narrow so increasing the width on OSM might not be the best solution. It seems width=2m, is used quite often as a measurement for the width of a road that can support 1 car. Which makes it incompatible with GH because as you said above that the assumed width of the car is slightly greater than 2m. Is it possible that GH could be updated to reduce the width to 2m as it seems we’ll hit this issue frequently and the road in question, although narrow does support the width of a car.

From our experience the width tag is indeed often used where the mappers estimate the width (and there is no explicit sign) and so we add a minor tolerance and so car should pass all widths including 2m. (btw: it would not pass if it is tagged with maxwidth=2m)

But in this case here the height is likely causing the access issue as we use 2m. I just explored the car-heights and Mercedes-Benz T ct, VW Caddy or Land-Rover Discovery come close but 1.9 would be sufficient. The problem is e.g. Land-Rover Defender 90 which might count as car and is nearly 2m, but we could let 2m pass and only block if maxheight is below?

Ah gotcha, I was under the impression that width=2m would prevent car from travelling on it.

The problem is e.g. Land-Rover Defender 90 which might count as car and is nearly 2m, but we could let 2m pass and only block if maxheight is below?

Yeah that makes sense to me, given that almost all cars are going to be under 2m

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