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Distribution of the Nodes

0

Hi, I'd like to know if there is any standard for node distribution in any way for the OSM. More specifically, I know that ways are created from points(nodes). However, is there any limitation for the position or (distance) of the next node? Ex: Say, I have a way, and it consists of 6 nodes. Is there any limitation for the distribution of these nodes? Is it possible to have 3. node very near to 4. node or 2. node? In contrast, is it possible to have 3. node quite far from the 2. node?

Thanks.

asked 08 Feb '22, 15:19

alisvndk88's gravatar image

alisvndk88
11335
accept rate: 0%


One Answer:

2

In general it depends on the shape and complexity of the object (or part of an object) in the real world that the way represents, e.g.

  • A long completely straight stretch of road may have 2 nodes a long distance apart
  • A roundabout may have a large number of nodes to approximately represent a circle
  • A building with a simple rectangular shape may be drawn with just 4 nodes
  • A building of the same size but with various protruding parts may need many more nodes.

Even within all those, it will also depend on the precision of the source that mappers are using, and to some extent on the personal taste of the mappers. There are no universal rules, for example, about how many nodes are needed to represent a curve in a road.

If you have a specific application in mind that has prompted this question, we might be able to give further guidance beyond my generic answer above.

answered 08 Feb '22, 15:59

alan_gr's gravatar image

alan_gr
2.6k12245
accept rate: 15%

edited 08 Feb '22, 16:00

Thanks for the info. I'm trying to estimate the curvature using nodes using 3 points(menger curvature). But, due to distributions, it is not accurate as I expected.

(08 Feb '22, 16:35) alisvndk88

Source code available on GitHub .