[OSM-newbies] How to draw land-use areas

[James Ewen]

On Sun, Apr 15, 2012 at 6:12 PM, Charlotte Wolter <techlady at techlady.com> wrote:

> Yes, I agree, but this guy is drawing the margins, not just in the middle of
> the road, but linked to the road, using the same points as the road. Also,
> he did this even when the land use is different on both sides of the road.
> It makes changing the road and/or changing land use a real bitch.

I would think the opposite... If the road is in the wrong location,
and you move the nodes that define the road, the land use on either
side is updated automatically. If the land use polygons were
completely separate, and you changed the geometry of the road, you
would then have to change the geometry of the land use polygons to
match the road geometry.

It's all in how you look at the map, and the mapping concepts. OSM has
no overarching body that says "You will map things this way!", so
everyone does things the way they feel is best. This can lead to
people mapping things, others ripping it up, and then an editing war
ensues.

My personal feeling is that if you're going to map landuse to the
physical edge of the road, then you should create the road as a
polygon to show the edge of the road sharing the edge of the landuse.
Hmm, let's see around here we would need to put the edge of the
landuse polygon on the edge of the privately owned land, and then
create a polygon for the government owned road allowance, and within
that road allowance, draw another polygon defining the physical space
occupied by the road surface.

The front of my city lot, which looks to be my front lawn actually has
6 feet of grass that belongs to the county, which is used for
utilities. Should I draw a residential land use polygon to the edge of
my property, then a county allowance polygon followed by a polygon
defining the sidewalk, and then finally a polygon showing the paved
surface of the road?

How much detail do you really need to convey? I would agree with just
making a large polygon that defines the full residential area, and
layering the roads over top of it. Reusing the nodes defining a
roadway as an edge of the land use polygon makes sense to me. It does
make it harder to manipulate only one entity that is using the shared
nodes, but that's a trade off that you have to deal with.

-- 
James
VE6SRV