[mkgmap-dev] Idea: map layers (multiple output tiles per input tile)

Sat Apr 9 21:14:59 BST 2011

On Sat, Apr 09, 2011 at 01:14:31PM -0500, Paul Johnson wrote:
>On 04/08/2011 03:19 PM, Marko Mäkelä wrote:
>> I got an idea today: Make the style language support layers, and allow
>> the user to specify which layers to generate and in which output files.
>
>You can already do this using the XAPI to pull the data you want for
>each layer you want to define in your own editor.

Sorry, I do not follow you. Sure, you can prepare all sorts of map 
extracts, and you may even filter map extracts with Osmosis. You can 
even filter stuff from the maps by using different mkgmap styles.

Maybe I was being unclear. The use case that I have in mind is the 
generation of a map set that comprises several layers (families in 
Garmin terminology). These layers can be enabled or disabled in the map 
settings menu on the GPS receiver.

Currently, this use case requires that mkgmap parses the input several 
times, once for every generated family ID, or every processed style.

My proposed feature would allow mkgmap to generate multiple map tiles 
from the same source tile. That is, in a sense, process multiple styles 
in one go. The benefit should be reduced execution time.

Best regards,

	Marko