Attached Link: http://www.youtube.com/watch?v=TVIt6XlX_mo

The technique I'm showing here is to isolate the windows you wish to be on by cutting them out (and the immediate surroundings if you want that), and shining a bulb light onto the cut out (and only the cut out).

This gives you the ultimate control over where you light falls, and because you can assign a separate shader for the new model you can alter how the light interacts with the window pane.

You could even set up more than one shading domain and shader to have the windows behave differently.

This technique is not the quickest but I would argue its the most flexible set up.

more tutorials at
http://www.scififunk.com
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