> there are already DX->GL compatibility layers, although most of them are in house, by companies that produce ports (ala Feral Games). And this is Valve relea

> there are already DX->GL compatibility layers, although most of them are in house, by companies that produce ports (ala Feral Games). And this is Valve releasing their particular variant mostly targeted at other major game studios. There is no reason every studio should be forced to create their own in house compatibility layer.