[Potlatch-dev] Proposed filtered way-drawing mode - thoughts?

[Steve Bennett]

I'd like to introduce an easier way to draw ways without colliding
with entities like admin boundaries, landuse, etc. I don't know about
other parts of the world, but it can be really tedious here trying to
work near such a boundary - you're constantly hitting it, making it
very hard to create nodes near the boundary.

I hacked up some quick code to see the effect of simply not being able
to make junctions with ways that only have those basic tags. So far,
so good. Question is: what's the best way to let the user control
this?

I can think of a few options:
1) Have a hard-coded filter that blacklists ways that consist of only
a defined list of non-physical tags (boundary=*, admin_level=*,
name=*, perhaps landuse=*, ...) Let the user turn the filter on or off
with a key stroke, or perhaps even a mouse modifier.
2) Do the same but with a whitelist: only connect with ways that have
at least one physical tag (highway=*, natural=*, ...)
3) Like 1) but with a user-customisable list.
4) Like 2) but with a user-customisable list.
5) Have a keystroke/mouse modifier that disables all junctions,
period. (This wouldn't help the situation where a road and a boundary
are very near each other and you're trying to connect with the road).
6) Implement a proper filtering system that both hides the filtered
objects and avoids junctions with them. (Me, I'm not fussed about
seeing the unwanted objects.)

Also up for discussion is whether filtering out an object should avoid
all selections of it (as well avoiding junctions). Probably yes.

So far I think I like 3, but don't think I could code the customisable
list at this stage.

Comments?

Steve