dude, i am sorry that i am the one to say this, but you ruined the whole rose-window thing you had going by changing the shape. I say make it circular again, stained glass, not so much grating (remember that welded lead held it together). If you really want it to looks authentically cool, add some more stained glass windows. My suggestion is make a tall one, a little narrower than the rose window, and place it under said window. Then make the light filter through it at an angle anywhere from 50 to 80 degrees, creating a beam of light that stretches accros the floor illuminating the whole place, with the colors of the stained-glass window(s) mirrored on the floor, although obviously a paler shade. Then place the other windows so that they let less light through than the bigger one, but still partially light up the non-light places (cause of the angle of the "sun").
All in all, i think that this would create an awesome overall lighting effect that would go along very well with the architecture of the level.
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Life is too important to take seriously.
~Oscar Wilde
There's a fine line between genius and insanity. I have erased this line.
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