to U both thx a lot for the tips
it works great as long as camera is not too close from the master object (for whatever reason, 3d datas goes crazy at this point)
actually I'm not a "C4D killer" and I prefer to handle the compositing of the screen content into after fx : simply much more possibility to mix and create animation. the content is about software, so I need to animate according to the overall rotation in front of the cam :
some other rough try with the red part that shows AEFX solids
http://xzuxzu.free.fr/ccow/ccowworks.mov
as you can see there is also a small distance between the image and the screen. this is why I want AEFX to composite : it will look like holographic images and some 2D images will explode out of the screens. anyway, the way to handle it with C4D (and that is the thread here) works perfect !
