Game engine code and data types creep into all your code. I once heard an indie game developer describe this as "smushing playdough against a mold" (where your

Game engine code and data types creep into all your code. I once heard an indie game developer describe this as "smushing playdough against a mold" (where your game-specific not engine-specific code is the playdough and the mold is the engine API).