[Bf-committers] Driver Source needed

[Tobias Oelgarte]

In the recent days i made heavy use of drivers for corrective shapekeys. 
But curiously there is not a single source (beside "rotational 
difference" which is not signed) that includes the visual transform 
(with constraints). Thats why i wrote a script to get a bones rotation, 
which is relative to its rest pose and includes animation + constraints. 
I think it is very usefull for various purposes to have access to this 
relative and final rotational information. Could we add something like 
this to the driver sources?

http://www.pasteall.org/blend/14452