Prior to PS3, real-time rendered 3D graphics might have looked real, but they weren't actually calculated in a fully 3D environment. But that was OK for screen resolutions up until now. Even as of the current time, most of the games for the Xbox 360 use that kind of 3D. However, we want to realize fully calculated 3D graphics in fully 3D environments. In order to do that, we need to share the data between the CPU and GPU as much as possible. That's why we adopted this architecture. We want to make all the floating-point calculations including their rounded numbers the same, and we've been able to make it almost identical. So as a result, the CPU and GPU can use their calculated figures bidirectionally.