[Bug 20755] New: W-buffer not well handled

http://bugs.winehq.org/show_bug.cgi?id=20755

Summary: W-buffer not well handled
           Product: Wine
           Version: 1.1.32
          Platform: PC
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: minor
          Priority: P2
         Component: directx-d3d
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

There are some minor display problems in Mafia. In particular, at the very
beginning of the demo, when people are sitting around a table, their eyeballs
seem to pop out of their heads. This is probably due to the fact that Mafia
uses a W-buffer, while Wine handles it as a Z-buffer (this can be seen in
dlls/wined3d/state.c).
Moreover, I get this fixme message:
fixme:d3d:state_zenable W buffer is not well handled

Would it be a lot of work to add support for a W-buffer in Wine? (the
WGL_EXT_depth_float OpenGL extension might be used)