[mapserver-dev] ms rfc 48: adding a type keyword to the styleblock

[Daniel Morissette]

thomas bonfort wrote:
> 
> the original intent of this rfc was to have something a bit more
> generic than directly adding arrowhead support, so this is getting a
> bit unwieldy  :)
> 

Ha! I know that feeling!

Guys, let's keep in mind that the simplicity of MapServer used to be its 
main advantage? Did we forget that "MapServer is not a full-featured GIS 
system, nor does it aspire to be"?

While it may sound cool to perform a 
centroid(convexhull(buffer([geom],0.5))) in a style at rendering time, 
that remains a purely theoretical example with no application in real 
life as far as I can tell... BTW, do we also expect that a feature 
rendered after such a complex operation should be clickable (queryable) 
as well and how do we plan on managing that if all those operations are 
done only at rendering time in the style object and not in the data 
source where the query happens?

If anyone needs that kind of fancy operation, I think they can afford to 
load their data in PostGIS and do the spatial operations in there 
instead of bloating MapServer with stuff that's of no use for 99% of the 
users... that will also solve the queryability issue.


> The idea of having a single geometryexpression keyword leaves many
> possibilities as to the transformations of the original geometry, do
> you think that the nested expression stuff could be postponed? (I have
> limited time and ressources to get this in, but the concept appeals to
> me so I'd like to dig in further in the longer term)
> 

I'd say keep it simple and manageable in the time that you have 
available, and plan the mapfile changes/keywords so that they can be 
extended in the future if possible... that's what you've done so far I 
think.

The RFC and future docs should also discuss the impact of the use of 
geotransform on queries.

Daniel
-- 
Daniel Morissette
http://www.mapgears.com/