Note: I have only cut out the tops of the windows because I wanted to use the self illuminating material to light up the remaining window. This will give the effect of something blocking the window from the inside and help create a more realistic 'fake' room. Also if I cut out the entire window the light that escapes would over-power the image and ruin the look.
To create a self illumination map you need to create a black and white image of the texture, black being not illuminated and white being illuminated. The black and white image is placed in the self illumination slot of the material.
For the real lights I used two MR-Area Omni lights and placed them inside the 'fake' room.
Here are the settings I used (Fig.17).
I used the light from the windows to help define the building on the left and make sure it stands out from the background building.
Here is a render of the image so far (Fig.18).
Here you can see the light creating an outline of the building on the left making it stand out from the background building. Also the variation of colour difference from the self illuminated windows and the real windows gives the impression of an actual room with genuine atmosphere inside.
Once the windows were lit in the foreground, the building above the archway began to lack detail and 'got lost' in comparison with the other buildings in the scene. There is a window to the right of the door. I used the same methods as before and cut out the window and hollowed out a 'fake' room behind, duplicating the same MR-Area Omni light that was used in the other 'fake' rooms. I placed the light behind the window and kept the settings the same.
And here is a render of what we now have (Fig.19).