[Talk-GB] Mapping of Kielder Forest(s)

[James Derrick]

Hi again Russ,

On 30/08/2021 19:59, Russ Garrett wrote:
 > First off I would like to emphasise that I am not suggesting the
 > removal of any detail here.
 >
 > I am suggesting that small gaps in the forest should not be
 > represented by gaps in the forest polygons, but should be replaced
 > with man_made=cutline (and/or a highway tag), which would reduce the
 > number of individual landuse polygons. Larger gaps (such as the old
 > farmsteads, etc) should certainly be preserved, potentially as holes
 > in a multipolygon.

It may be me, but these two statements seem to be incompatible.

In several areas I have taken the time to (start to) micro-map 
individual stands of trees with a single area. As cutlines/ firebreaks/ 
haul roads are seldom linear features (river ravines, farmsteads, 
bothys, stone walls, shedding rings, gullys, etc), this is additional 
information with real features useful for navigation - remember not all 
maps are consumed on a GPSr.


Rejoining these areas into one larger area and adding linear ways to 
represent (a few of) the gaps in trees in my mind absolutely is removing 
detail.

I'd all it **macro-mapping**, at the risk of creating a hashtag.


In areas where the mappping complexity is low, an outer area 
landuse=forest plus ways man_made=cutline makes a lot of sense - it 
gives a good balance of effort / useful detail.

This isn't the case in Kielder, however. A lot of detail was imported in 
the past from other sources with individual stands of trees, and broken 
into small areas / import viewport clipping fixed later.

As a simple example of imported data showing pre-existing areas:
	G3YAC imported from OS_Opendata_Natural_Line
	https://www.openstreetmap.org/way/131625930/history

Would you join these relatively rectilinear areas and add cutlines?
	https://www.openstreetmap.org/way/131625842/history
	https://www.openstreetmap.org/way/131625810/history
	https://www.openstreetmap.org/way/131625930/history

I was about to reference a more complex case but...


 > I'm not suggesting that the entire area should be tagged as "Kielder
 > Forest".

Sadly, after looking around Kielder observatory, I see you've already 
started merging areas and removing detail:
	https://www.openstreetmap.org/way/383346121/history
	https://www.openstreetmap.org/changeset/110350625

A single 50km2 (roughly 6km x 4km) multi-poloygon is a poor replacement 
for the previous detail, and I ask you to stop **macro-mapping**.


James
-- 
James Derrick
     lists at jamesderrick.org, Cramlington, England
     I wouldn't be a volunteer if you paid me...
     https://www.openstreetmap.org/user/James%20Derrick