v4 - added --remove-bogus-nodes option to turn on this feature. Even though the reduction in nodes is fairly modest (typically 5-10%), I believe that this could be useful for those routable ways that share many points with non-routable lines or areas. A lot of roads do share points with neighbouring areas and in those cases, this option should remove a lot of bogus nodes. Whether that translates into improved routing in that region is yet to be proven. ---------- v3 - now duplicates ways so that any structural changes to the way made while processing a line/road will not affect the original way and so each map object generated from the original way will see the full set of points in the way. Duplicating the ways appeared to have no noticeable effect on the run time when processing the GB map. -------- v2 - avoid assertion when more than one routable way is generated from the same OSM way ------- With the recent reversion of the Table A breakage, it's now useful to post this patch for wider testing as it no longer causes my Nuvi to barf. What it does is remove routing nodes from ways that should never have been put there in the first place. Without this patch, a routable way will have a node for each of its points that are shared by any other way (whether the other ways are routable or not). For example, at the moment, if a way shares its points with a boundary line or shape, each of those points will become nodes. From the routing point of view, that's (essentially) harmless but having extra nodes does take up space and must slow down the routing calculation. It therefore makes sense to remove the bogus nodes. What this patch does is defer the processing of all of the points/lines/shapes until after their types have been computed. Having computed the ways' types we know what's routable and what isn't so nodes only need to be created where routable ways meet. That's the theory, in practice, it produces slightly smaller maps. Whether it actually improves the routing quality is yet to be determined. Obviously, the gain you will see depends on how many bogus nodes are in your maps. All feedback welcome. Mark