[Talk-ca] Geobase related fixes needed in Mapnik and Maplint

[Lennard]

Pierre-Luc Beaudoin wrote:

> Oh! Thanks for the enlightenment.  Can't we improve it then to not
> render repeated signs for prettier map output?  See the 360 on this map
> http://www.openstreetmap.org/?lat=47.1061&lon=-70.8097&zoom=12&layers=B000FTF

Every time mapnik encounters a new way, it takes it at face value, and 
restarts the shield rendering and shield repeats along the length of the 
way. As Richard pointed out, the min_distance is 120px, so it starts 
rendering the first shield of the next way a minimum of 120 pixels away 
from another shield.

Point is, to us it looks like one long way, and we would maybe assume 
that a single shield would suffice, but to mapnik, it's a collection of 
unique ways, each taken at face value.

Increasing the min_distance would introduce more problems where 2 
shielded highways are close to each other.

Still, it's a nice idea, and would perhaps be possible either be 
preprocessing the data in additional ways, or by enhancements to mapnik 
itself. Needs someone to try, test and implement it.

-- 
Lennard