Although it's not addressing all the feature requests so far, over the
weekend I've updated the Addon to work on pre-existing lights which
should provide support for Arnold and VRay. In the tests I've done with
Arnold lights it works fine. i.e. just select an existing light or light
root and the tool will take over manipulation of that light.
Fixed a horrible bug (in my implementation) with non-uniform scaled
normals. Source has been tidied and extensive use has been made of code
kindly supplied in this invaluable thread:
http://www.si-community.com/community/viewtopic.php?f=16&t=1658
Hopefully will get a chance soon to address moving the light along the
incident ray in a useful way. For the moment all lights are place a
fixed distance away. Suggestions for what to do with the mouse vectors
and how to derive a sane, non-flickering, predictable in/out motion for
the light when Shift LMB pushed gratefully received!
New addon is here:
http://julianjohnsonsblog.blogspot.co.uk/2013/01/place-specular-highlights.html
Julian