Square develops their games on PCs ever since FFVI - according to Nomura.
Originally White Engine was meant to only work with PS3 - that is true. But after SE realised that PS3 isnt going to be the leader this gen they made it multiplatform and changed its name to Crystal Tools.
They invest a lot into this technology. They really want to adopt the western style of development - when a developer builds an engine at the start of the console generation and then uses it till the very end of this generation for every game. The only differense though is that it takes too damn long for SE to do so. But if everything goes as planned then we are going to see a lot more games built on CT in future.







