why are you trying to compensate for that effect? it is natural for it to be there, so removing it will make your program look less natural. you may have to adjust the angular width or the total horizontal space you can see at once, though. one that's used a lot is 60 degrees.
For some reasons, I don't think I have noticed any FPS for the computer with that effect 
, or maybe it's due to the fact that every FPS I played were made back in the days where computer screens were not flat. Also when I take pictures with my camera walls always look like figure 18
I think that's as a result of
barrel distortion... which sometimes happens with digital cameras.
