Nearest polygon

[jfoclpf]

When a certain point does not fit within any known polygon, is there a way to calculate or output the nearest polygon and the distance thereto?

[missinglink]

Hi @jfoclpf, no, not with the current API.

It is however possible to achieve something like this using the rbush library we are using under-the-hood. The data model is an R-Tree so you should be able to provide an input bounding-box instead of an input point.

There are a few things to note:

• There is no way to know the minimum size bounding box you'll need to input to ensure a hit
• The algorithm is different from the Ray Casting algo used to test a CONTAINS relationship, although its basically the same thing (ie. find the closest edge and then find the closest point on the edge).
• Passing a bounding box which intersects many polygons will require doing work on every matching polygon, which has the potential to be considerably slower than the existing point-in-polygon API.