[mapserver-users] hatch symbol edge effects when rendering tiles with TilecCache

[SQ9MEV]

Hi all!

Working on my first webgis app, I use mapserver with python mapscript to 
generate WMS tiles. I use metatiling (5x5), but

I'm struggling with edge effects when using hatch filled polygons - 
hatch pattern is moved by some offset on neighbouring tiles (I use 
metatiling, but it cannot resolve my problem, as polygons share several 
metatiles sometimes).

The problem is somehow mentioned in MS RFC 45:
http://mapserver.org/development/rfc/ms-rfc-45.html?highlight=hatch#polygon-fill-symbols

but not a word about how to get rid of the edge effect.

Any hints how to achieve repeating hatching accros many tiles?

I think the pattern should have stable geographical origin as it's 
mentioned or at least "stable tile origin".

I do not need continous hatch pattern, so as for now i use workaround:

SYMBOL 'hatch-test'
PATTERN 2 3 1 4 2 4 2 3 2 END

The gaps are more or lesl random, so edge effect is not so visible as 
with continous hatch, but it is.

Anyway, my map looks reasonable, so thanks guys for your work on MapServer.

-- 
Bart