If you need to incorporate flexibility in the environment, with agents displaying lots of different behaviors (such as with video games), the large arrays of du

If you need to incorporate flexibility in the environment, with agents displaying lots of different behaviors (such as with video games), the large arrays of dumb structs will be much harder to organize. I agree that those structures are easier to make efficient, but for handling the hierarchy of different types of objects with different but related behaviors, you'll basically have to reimplement a limited form of object-orientation and message passing.