[talk-au] Murray River #2. Thanks heaps.

[Warin]

On 9/4/20 5:56 pm, Little Maps wrote:
> Hello again everyone, many thanks for your fast and informative feedback! It’s great to join such a welcoming group.
>
> There’s lots of great advice in everybody’s emails. If I distill it to one key point, I think it is...
>
> 1. Don’t touch admin boundaries or you’ll “rip me bloody arms off”, to quote an old TV personality. Further to this, don’t join natural features with admin boundaries etc. Point taken, I’ll steer clear of them all.

Err well ... Sometimes Admin Boundaries get connected to things .. and when someone mover them then they accidentially move the Admin boundary... and that is frustration on all sides. But understandable.

>
> 2. From what I can deduce from your points, the river itself (in real life and as mapped on OSM) doesn’t carry any administrative information whatsoever. It’s purely a natural feature like clearings, tree cover, beaches etc. (This is obvious from a technical point of view but not something I had properly understood in a broader sense before). Please correct me if I’m wrong in this.

See above comment.

And the boundary from Vic to NSW was legally linked to some part of the Murry River ...

>
> 3. Taking on board the helpful comment to “work on what interests you”, I think I’ll focus on natural features and recreational features such as tracks and popular campsites. I worked out today how to hide all administrative boundaries in JOSM to make sure I don’t accidentally link to or alter them.

See comment on 1.

>
> 4. I spent today reading tutorials and working out how best to map natural features. I selected a small unmapped area, mapped everything I could and then deleted the day’s work to make sure I didn’t upload any mistakes I might have made before I worked out the process and a coherent workflow.

No need to delete it- you can save your work locally (save as) .. just don't upload it. If you do - ask for someone here to 'revert' it. That is easy to do for smaller things that have not been there for a while.

>
> 5. The natural features I’d like to add are tree cover (i.e. “wood”), large clearings, beaches and oxbows, wetlands etc, especially on public land. Apart from some large wetlands and oxbows, there are many stretches where none of these features have been mapped. Could I ask for your feedback on the following process please?
>
> 6. In many places, the area to be mapped is bounded on one side by the river and on the other by the outer edge of tree cover. Nearly all other features lie within this envelope. The approach I trialled is as follows...  (this approach is only workable if small sections are done at a time.)
>
> 7. In a small area, map the outer boundary of tree cover, starting and finishing this way at the river. Split the river way at the start and end of the new tree cover way and create a multi polygon using the river boundary and the tree cover boundary as the outer boundaries. Then work within this area and map all sizeable clearings, beaches, oxbows and wetlands etc as inner boundaries etc within this multi polygon.

Yes that works. However (there is always at least one catch) the river 'edge' may be linked to other things too. So download the river 'edge' and it should come with every other thing that uses it. When you split the river way JOSM will then inculde both bits of the split way into the existing relations - so they won't get broken by your work.

>
> 8. This approach provides a uniformly mapped area from the river outwards, with no gaps between adjacent polygons. A potential sequence along a transect from the river outwards might include for example, the river, a large beach, woods and trees, interrupted by a series of oxbow lakes and wetlands etc. The slowest part of the process will be mapping the many large wetlands as there are lots in some places.

Don't be afraid of leaving gaps! There is no agreed tag for 'nothing is here'. If you cannot make something out - just leave it unmapped.

>
> 9. If the river itself carries no administrative meanings (see above) then it is ok to refine the river boundary. Life is too short to do this along long stretches but some refinement would be useful where popular campsites, most of which are on big sandy beaches, abut the river. This way the river-beach boundary would be accurately placed (acknowledging changes in river water levels).

See reply to item 1.

>
> 9. I can then add tracks and campsites etc within the mapped area before uploading it all and starting a new section.

Campsites... I'd not map 'unofficial' ones. Where you do map them, if you can, include things like fee=yes/no, toilets=yes/no, caravans=yes/no, tents=yes/no, showers=yes/no.

>
> 10. There are natural gaps in tree cover in many places along the river which means that the above process can be repeated on sections that are not immediately adjacent which simplifies things. I haven’t contemplated how to map very large areas of continuous tree cover without creating a nightmarish multi polygon but I can avoid this more complex problem for some time as there’s lots of small, discrete gaps to fill.

Tell me about large tree covers! The Great Dividing Range is full of tree cover.

>
> 10. After a few sections I’ll probably go bonkers and give it all up, but I’ll be driven up the wall even faster if I stay locked up under the important coronavirus laws without a task like this to keep me occupied.

Once your sick of tree cover .. try something else. Farms? Creeks? Whatever. There is heaps to do.

>
> My apologies for sending you all such a long message but once again I’d really welcome your feedback and suggestions. I’ll then work on a small area as a pilot, upload it, and welcome your feedback on things I can improve on, if you can bear hearing from me again.

No worries.  There will be disagreements from time to time over some thing .. usually a misunderstanding of the meaning of something within OSM.


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