-- optimize too-slow AI / FOV algorithms; maybe use
- <http://forums.roguetemple.com/index.php?topic=3675.0>?
+- bug: -v works, and -vs, but not -sv – why?
+
+- consider
+ <http://www.plomlompom.de/PlomRogue/plomwiki.php?title=TheCreationOfSpace#comment_0>