http://bugs.winehq.org/show_bug.cgi?id=26863
--- Comment #7 from Night Nord NightNord@gmail.com 2011-04-21 02:33:46 CDT --- You mean r_portal_stencil_depth? I already reported it into AMD's bugzilla: 1 - fail 0 - not fail (for portal 2). I'll test it on portal 1.
When portal depth == 0 it won't fail, but if I'll try to get though portal - it will. I suppose it's about portal decorations or effect of portal opening, not about portal itself.