Sorry if this is somewhere else, but I am wondering if I want to play on the PC and I have a copy of the PS3 version do I need to buy a digital download at some point or a PC version in order to play on both? Or can through the purchase of the PS3 version I can also play my account on the PC if I so wish?

I tried logging in to my partners account on the PC ( he has the PS3 version) and it wouldn't let me log it in. So do we basically have to buy 2 versions of the game to be able to play on both?

Thanks if anyone can answer my question!