[mkgmap-dev] Splitter details question

Thu Jan 14 12:27:46 GMT 2010

For what it is worth, my 2 cents:

On Thu, Jan 14, 2010 at 10:36:54AM +0000, Chris Miller wrote:
> 1) Nodes and ways get intermingled in the output OSM file. I don't think 
> this is a problem at all since there still won't be any forward references 
> from eg ways to nodes, but currently the splitter writes out <node/> tags 
> first, then <way/> tags, then <rel/> tags so maybe this will break/annoy 
> something/someone?

Relations can contain forward references to member relations (subrelations).
The forward references are unavoidable in the general case, because there
may be circular references, for example.  Even small map extracts downloaded
by JOSM may contain forward subrelation references even for tree-like
relation hierarchies.

I implemented deferred lookup of subrelations in mkgmap's OSM XML parser.
The parser still throws away forward references to nodes and ways.  

It has been pointed out earlier that JOSM refuses to load the files from
splitter.  Sometimes, it might be useful to load files to JOSM for
troubleshooting.  But JOSM cannot load big files anyway.  Could there be
some filter for "normalizing" the output?  And another filter for throwing
out uninteresting elements or attributes, so that the tile becomes small
enough for JOSM?  Perhaps something like this already exists?

Best regards,

	Marko