[OSM-dev] New OSM binary fileformat implementation.

[Scott Crosby]

On Sun, Aug 1, 2010 at 5:51 AM, jamesmikedupont at googlemail.com
<jamesmikedupont at googlemail.com> wrote:
> Hi, ist there any documentation of the binary format changes?
> I have implemented a c++ reader using protobuf, would update that if
> there is a new format spec.
> mike

No real docs. There are some tweaks on the edges with regards to
renaming protocol buffer message names and field names. Mostly
search&replace. Field numbers may have changed, so the earliest files
are not compatible.

There are a few semantic differences that affect parsing. Offset
numbers are now in the format that let the grid in the binary file be
aligned with a grid in a dataset for datasets with a regular grid,
such as isohypsis files. The other notable change is I have have
extended DenseNodes to support tags and so have removed the former
Node. This has resulted in '0' no longer being available for use as a
string identifier. It is being used as a delimiter.

In a week or two, depending on feedback and any resulting changes, I
will upload reference files to github. If you update the reader, I
would appreciate a copy,

Thanks,
Scott