SE 1.1 describes the possibility to set a PerpendicularOffset for a LineSymbolizer, just like SLD 1.0 does for the LinePlacement. I know that GeoTools is not a reference implementation for SE 1.1, but I know about AtlasStyler users that desire such a function.
In trunk the LineSymbolizer class has a setter and a getter for PerpendicularOffset, but the settings is lost when transforming the Style to and from XML, as well it is lost when the Style is duplicated with the DuplicatingStyleVisitor.
Attached are two patches:
1. Two unit tests showing that LineSymbolizer.set/getPerpendicular settings are lost when transforming/parsing/duplicating the Style.
2. A patch fixing the three cases above
The patches are created again '/trunk/modules/library/main'
What's missing is the implementation in the renderer, as shortly discussed here:
My symbolic offer for funding the renderer-implementation: I sponser this implementation with 200€ via paypal. I will send the money to any email chosen by the one that implements this in the renderer; or I can donate it to any organization of choice. I will not need any bills, as I fund this privately. In case anybody is willing, please tell me before you start via email
I would be very happy if I could commit the above patches and anybody would take the bounty.