I've been doing this a long time, I beleive I know what I'm doing. But yes I beleive I am a little crazy. If your really doing artwork a small repeated pattern of brick will give you just that a small repeated pattern of brick. I go out and photograph (multiple images) the entire side of a building "old brick buildings downtown are great for this" and use these images to map an entire wall! Like I said sometimes you may need to break it up unto 2 or more maps