[mapserver-users] Perpendicular offset different in Mapfile and SLD

[thomas bonfort]

Gertjan,
I've opened a pull-request for this issue at
https://github.com/mapserver/mapserver/pull/4801 . Could you please
comment in that issue if the fix is correct?

--
thomas

On 28 October 2013 13:43, Gertjan van Oosten <gertjan at west.nl> wrote:
> Hi all,
>
> I've noticed that there's an implementation difference between
> specifying a perpendicular offset in the STYLE section of the Mapfile:
>
>   STYLE
>     ...
>     OFFSET 3 -99
>     ...
>   END
>
> and specifying it via an SLD:
>
>   <sld:LineSymbolizer>
>     ...
>     <sld:PerpendicularOffset>3</sld:PerpendicularOffset>
>     ...
>   <sld:LineSymbolizer>
>
>
> The first one, via the Mapfile, does a complex offset calculation
> (function msOffsetPolyline() in maputil.c; calls msOffsetCurve() for
> perpendicular offset).
> The second one, via the SLD, simply does a displacement by the given
> value in both the X and Y directions (function msSLDParseLineSymbolizer()
> in mapogcsld.c).
> These two produce quite different results.
> [Note that the SLD one would be the same as specifying "OFFSET 3 3" in
> the Mapfile.]
>
> My questions:
> Is there a reason the two methods are different?
> If not, would it be possible to change the SLD one to use the same
> calculations as done for the Mapfile?
>
> Kind regards,
> --
> -- Gertjan van Oosten, Principal Consultant, West Consulting B.V.
> -- gertjan at West.NL     +31 15 2191 600       www.west.nl
> _______________________________________________
> mapserver-users mailing list
> mapserver-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapserver-users