-Remove the globals rw_frontcz1, rw_frontcz2, rw_frontfz1, etc. They are replaced by a struct wall_t that contains all 8 vertices of a wall (both front and back sides).
-R_FakeFlat now takes a drawseg_t parameter, allowing rw_start and rw_stop globals to be removed.
-R_ProjectSeg and R_PrepWall now have wall_t parameters to hold the clipped wall vertices.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4386 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Call R_FakeFlat to determine the front and back sectors for rendering masked midtextures, taking transfer heights into account.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4387 b0bcef46-2027-0410-bd56-ab726e9a1d04