[mkgmap-dev] Simplifying ways & rounding

Sun Nov 29 17:07:30 GMT 2009

Johann,

> The merge lines patch is designed from start for high line numbers. It 
> uses internal hashlists for performance reasons. I would expect the 
> runtime to raise n*log(n), not n². So I do not expect it to burn cpu, 
> but would need a test to proove it.

OK.

> But I'm not sure, if merging across tiles would improve the whole thing. 
> As far as I understand, a line could not go across multiple 
> subdivisions. So it has to be splitted anyway at its bounds. I expect no 
> usefull effects from merging before.

That's a good point, so it's probably not worth the effort to merge
lines across subdivs.

> What I really would like, is to apply the merge filter before any 
> creating of routing data. This would be the most reasonable place with 
> the most effect, even to routing quality.

That's true but it's non-trivial (as you know).

> But one step after the other....
> And I'm sorry, I could not spend that much time to the mkgamp project.

No problem.

Are you happy with the current state of the merge patch? If so, I can
commit it to trunk.

Cheers,

Mark