Only allocate bit vectors for clipping contexts that get used.

git-svn-id: http://mancubus.net/svn/hosted/eternity/branches/portal-branch@2554 86ba831e-150c-0410-ab35-e06eaae15ed9
Fixed compile issues with release configuration.

git-svn-id: http://mancubus.net/svn/hosted/eternity/branches/portal-branch@2555 86ba831e-150c-0410-ab35-e06eaae15ed9