On Feb 11, 2009, at 23:55, Steve Ratcliffe wrote:
The good news is that I *"think"* I have found the data that causes the problem. Call me sad if you want but I had a spare hour (not) so using osmosis I started splitting the tile giving the error into 4 quarters. I would run each of these and see if there were errors. I then split the quarter with errors and repeated the process until I was left with the attached file. In the bottom left quarter is a tiny roundabout. If you just move the north node northwards and the south road southwards a couple of feet then the tile runs without errors.
Nicely tracked down.
It turns out my patch above fixes the IllegalArgumentException, though I don't really know why, since the roundabout isn't really close to longitude zero. Also I don't know if it doesn't break anything else, so I'm hesitant about committing it.
The northmost and the eastmost points on that roundabout are about 5m apart and routing nodes have to be more than 5.4m apart.
Do we know why this is? I remember in the length calculation discussion that the unit of arc length was 5.4m, but we could just lie for shorter arcs. Cheers Robert