[Mapserver-dev] content-sensitive legends

[Chris G. Nicholas]

Has anyone ever sized up the level of effort to make legends, specifically classes with a *bunch* of expressions, to only draw those items in the legend that actually appear within the mapextent? 

I can imagine a flag in each of the "candidate" legend items, that, during a mapdraw, would get set if it were actually traversed, but I am sure there is a *lot* more to it than that...

Anyway, this is of considerable interest, since some of the layers we are playing with have an innocent-looking column called "feature type", and although only a handful are ever drawn in a single map, there are a great number of them.

thanks in advance - 

Chris