Hi Greg, hi Gerd, yes, it would be great if the splitter throws those elements away. But that's a discussion that pops up every few months. Filtering out those elements seems to be difficult and makes the splitter *much* slower. As far as I understood you need (at least?) two passes of the input file for that. Splitter would have to detect all ways that intersect the bounding box and all ways and nodes that are part of a multipolygon intersecting the bounding box. That also means that splitter has to implement an multipolygon handling. Routing and multipolygons require the splitter overlap functionality. By increasing the overlap parameter many more multipolygons are complete or in such a status that the MP algorithm of mkgmap can do its best to guess how the holes must be completed. The patch also removes all ways and nodes without any tag. They exist because mkgmap only loads tags that are referenced by the style. But mkgmap cannot throw them away during loading because they might be referenced by multipolygons. The patch has bug: Ways and nodes without any tag must not be thrown away if they are referenced by a relation. The relation might be used to tag the ways and nodes (e.g. a bus route). I will post an update later on. WanMil
Hi,
this is another performance improvement:
Usually the mkgmap input tiles are larger than the processed bounding box (splitter parameter overlap). So there are much many elements which are processed but thrown away at a late step in mkgmap.
The patch tries to remove them much earlier before the style files are processed and before the LocationHook starts (which ignores them but that must also be calculated).
The patch contains one drawback: Ways which have all its points outside the bounding box of the tile but which cross the tile are also removed. If that's a point the patch must be improved.
Have fun! WanMil
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