[mkgmap-dev] Missing ways part 1

Fri Oct 22 08:17:01 BST 2010

Hi Adrian

> I have investigated further and this is what I have found.

Thanks for persisting and looking into this further.

> This bug could be fixed in either of two ways:
> a) Clip the ways in splitter so they are no longer defective.
> b) Modify mkgmap to accept defective ways and clip them itself.

> At this point it needs someone with a detailed knowledge of the
> software, to say how the interface between splitter and mkgmap should
> work, i.e. whether a) or b) is the correct approach. Only then could
> bugfixing efforts begin. I hope that the additional information I have
> provided, will make it that much easier to trace and fix the bug.

The answer to your question is that splitter and mkgmap take approach
b).

Mkgmap is supposed to chop every line that crosses the bounding box at
the boundary and insert a point there no matter how many times the
line crosses it.  Polygons are sliced so that they remain polygons.

This all works usually, so there must be something about the ways
that don't work. Is it every way that extends beyond the overlap
region that goes missing?

[As an aside, mkgmap is capable of working either way a) or b).  So if
you had a splitter program that introduced nodes on the boundary they
have to be tagged with mkgmap:boundary to distinguish them from real
nodes.]

..Steve