[Talk-ca] Deleting existing roads...

[G. Michael Carter]

OK this is really starting to bother me.   Roads are scary!!!

I tried seeing if I could take two CanVec block and merge them with 
existing roads.   Well I created a mess and ended up deleting the 
blocks.   CanVec data has many little differences... ie: where the nodes 
are, barriers, location of the roads, the break points between grids, 
road names... see below (grey CanVec), purple GPS, and orange existing 
GeoBase.   I even had an entire section in a ski resort that the GeoBase 
had no names (15 ways), where CanVec does and has road barriers too.  I 
have a feeling the GeoBase uploaded to Ontario was something like V5.0 
where the CanVec is V6.0 data.  Every difference I've found has proven 
to be more accurate.

I have to make like 500-1000 changes per grid if I try to modify 
existing GeoBase.   If I do it the other way around, and replace the 
GeoBase.. I'm finding I have 20, if any, changes per grid.  With 500+ 
changes my change of making a mistake --like not connecting the roads 
properly for routing-- increase.   CanVec roads line up and connect 
perfectly with CanVec roads, and other CanVec data.

So my question here:

How much of a problem is it if I miss tags like "one-way" or move a road 
that was placed via something other than GPS trails.   By replacing the 
GeoBase/Yahoo roads, then adding and connecting the few that CanVec is 
missing?  Plus adding the few tags that I find.

Personally I see more benefit to using CanVec road data.  Like the 
screen shot below, CanVec Road Network,  lines up with GeoBase 90% of 
the time and Yahoo maybe 25%.  In every case I've seen CanVec data lines 
up better with GPS data.   Also the CanVec data is going to line up 
better with other objects in CanVec, like forests, green spaces, and 
address information.   It's just way eaiser to replace the existing 
roads with CanVec, then modify the CanVec to fit any problems, than the 
other way around.

I just don't want to piss anyone off here.   I've done 70 tiles so far 
and just wanted to get keep going/no go from the community before I 
continue.


Example #1

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