How to use JOSM to draw immediately adjecting area

How to use JOSM to draw nearby area such as landuse=* which automately join to immediately adjecting existing objects while using the common nodes without click on every existing nodes need, while I drawing additional segmemt not adjecting to existing objects

For example, to draw a farmland immediately adjecting a forest, I want automatly convertly a newly drawed non-closed segment only two commonly not adjecting to existing forest to two closed objects while use common nodes.

Use more simpler to describe is:
How to draw a nearby area while only two terminal nodes with common to existing one, to convert to two closed area using common nodes to adjects each order in one go.

I’m not sure what “adjecting” means, but it seems like you’re asking about adjacent areas. If so, you’ll probably find JOSM’s built in Follow line tool helpful. You might also try installing the Contour merge plugin. Both of these provide an efficient way to get two adjacent areas to share nodes along an edge.


You also have the option of using multipolygons. Split the first boundary at each end of the section it shares with the new area you are drawing and create a multipolgon of the first area. If you create a multipolygon for the new area you can re-use the section common to both and then you only need to draw the remainder of the area to complete the mp.
Doing it this way you don’t need to redraw or retrace parts that another mapper has already done and there are no duplicated ways.
This method is normally used on larger areas with long sections sharing a common boundary.

One I certainly been longing for since ages…thx.

Another option that is sometimes appliciable when you are the one drawing both of the polygons in the same session, and don’t want multipolyons:

Draw the outline of the union of the two polygons, then draw the way between them and use it as a split way. (alt-x in utilsplugin2)

This is of course not always practical, but it’s in general often worth considering different drawing orders.

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