Re: [udig-devel] enabled tilecaching results into rendering problems if

[Andrea Aime <aaime@xxxxxxxxxxx>]

Jody Garnett ha scritto:
> I think Emily and Jesse will need to answer you. Emily did put in some 
> time to sort out labeling issues for tiled rendering; currently tiled 
> renderer is fatal on the mac (crashes the JVM) so I have not been 
> testing it myself. I will try again now that we have switch to Eclipse 
> 3.5.2...

Generally speaking, you cannot have tiling and good label rendering
at the same time.
The general trick to reduce labeling artifacts while tiling is to
"meta tile", that is, generate a 3x3 image and slice it up.
Of course the label issues will keep on appearing at the "meta tile"
borders, just makes the artifacts less frequent.

An approach to get good labels that I've used in OpenLayers is
to take the style, slice it up and make two, one for labels and
one for everything else, then render the labels un-tiled and
the rest tiled. That gives most of the tiling advantages
without sacrificing decent labeling. Of course it comes with
some performance overhead as labeled features need to be
read twice.

Cheers
Andrea


--
Andrea Aime
OpenGeo - http://opengeo.org
Expert service straight from the developers.