aq 3/4的作者BugMaster这么说
http://doom10.org/index.php?topic=136.0In this case the problem is probably --aq-mode 2 with using MBTree (it is known to have problems in fades and probably dark areas). And that is why I trying different other modes (AQ3 and now AQ4) to fix this by tuning them specially for use with MBTree.