[mkgmap-dev] splitter coordinates

Sun Jun 6 20:19:00 BST 2010

Hello Torsten,

The splitter works on a range of -180 to 180 longitude, and -85 to 85 degrees 
of latitude (the extremes are discarded to avoid crazy behaviour near the 
poles). So yes, -5 degrees should give you what you want, and the same logic 
applies if you want to include the equator. Creating a tile that spans the 
180 degree longitude line isn't currently supported by the splitter because 
it doesn't yet deal with wrapping around from +180 to -180. Note that this 
also means no 'overlap' nodes will be included if they fall on the wrong 
side of the 180 degree line.

The lack of 180 degree wrapping is a limitation I'm aware of but haven't 
fixed because it's a slightly tricky fix and it doesn't seem to have caused 
people any problems in practice so far. Is it likely to be a problem for you?

Chris

> Moin,
> 
> I want to use splitter (r109) for cutting a predifined tile that
> includes the prime meridian.
> 
> How do I set the coordinates west from the prime meridian?  I tried to
> set the minimum longitude to 355 degrees, but the resulting tile was
> empty. Must I use -5 degrees instead?
> 
> And what about a tile including the equator or the 180 degrees
> longitude?
> 
> Gruss
> Torsten