[Imports] [Talk-us] MassGIS Building Import - simplify

[Greg Troxel]

Jason Remillard <remillard.jason at gmail.com> writes:

> Hi,
>
> I would like to continue the discussion on the simplification of the
> MassGIS buildings in a new thread.
>
> In my town, there are 5427 buildings. 43,628 nodes, or 8 nodes per
> structure. I did a 0.25 meter simplify on the entire town, and the node
> count went down to 41,809. We are looking at an excess of 5%. 0.25 meter
> may seem tight, but consider that source data was from 30cm and 15cm per
> pixel, and I am sure the algorithms used do some kind of sub pixel
> interpolation. Until I can figure out how to do the simplification from my
> scripts, we will add instructions on the wiki on how to do a 0.25 meter
> simply on the source layer in JOSM first.

It would be interesting to see the histogram of %simplification.  I bet
most buildings result in no simplification, and a few a lot, but I
really have no basis for that.

I don't think the 5% of nodes is so important as that those 5% are
likely in a small number of buildings which are way overnoded.  So I
think it's good to do.
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