MS-RFC-27: Label Priority

Daniel Morissette dmorissette at MAPGEARS.COM
Tue May 22 16:01:28 EDT 2007

Frank Warmerdam wrote:
> Can you comment on why you use a multiple cache approach instead of doing
> a quicksort on a single cache based on the priority value?  A quicksort
> is order n-log-n which should be a very modest performance impact.

But the array of caches has zero-cost, that's even better. Well, the 
cost is the limit on the number of possible PRIORITY values. If others 
think we should be doing a sort then I'll look at that possibility, but 
personally I don't like the impact on performance, no matter how small 
it is.

> Also, is the priority something that can come from an attribute?  I think
> i'm asking if there is a corresponding PRIORITYITEM though I'm not sure.

Good point. I added that as a question in the RFC. I'll have to look at 
how Steve handled the RFC-19 stuff and see if we can apply the mechanism 
in this case.

> Lastly, should the RFC touch on the corresponding mapscript changes?

I've added a "MapScript Implications" section (one-liner).

Daniel Morissette

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