The import hit a roadblock. At the moment I am waiting for a license terms clarification from Boston GIS, since the current one was not considered a license by imports/talk-us mailing list members.

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Now, while I am waiting to hear back from Boston GIS, I decided to proceed to the second phase - splitting the buildings that house more than one, well, house number.

And there are a lot of these in Boston.

Original building import was done a while ago, and most of the buildings were left in the original shape. Since then MassGIS came up with a number of updates shapefiles that, if imported originally, would have made the whole process much easier. Since replacing the geometry for every building in Boston was out of the scope of the import, I decided to proceed with manual terracing of the buildings, verifying weird cases via Bing satellite maps, learning how to use the tools and mastering the skills of spotting building differences.

Now, you may ask, why don’t I just use the shapefiles provided by MassGIS? Well, as I already realized, imports are painful for OpenStreetMap, and replacing the whole city would create more pushback than I’d like to handle. I tried to copy a small number of buildings from MassGIS Data - Building Structures (2-D, from Ortho Imagery), but a lot of them grew arcs on the corners/bay windows missing from the real world:

And in the previous version every building had around 8 extra nodes along the perimeter that had no real use. At some point I’ll probably get bored and will probably do an automatic removal of collinear nodes (there must be a tool for that already somewhere).

This is a tedious job, but the results are awesome - I’ve got through all issues in Back Bay, Bay Village, currently progressing through South Boston part, driving the number of unique buildings up. Even if SAM import does not happen now, split buildings will allow for easier number assignment later, and granular automatic geometry updates as well.