Why did Sony choose to code a new engine for PlanetSide?
The simple answer is that writing their own unique engine allows them to create technology specifically suited for the game. Although the engines available are great engines, they are generally made for a specific type of game (UT or Q3 built for indoor environments, Tribes for outdoor, etc.) PlanetSide encompasses all these aspects in addition to such things as vehicle physics and a flight model. Not to take away from any of those engines you mentioned, but “re-inventing the wheel” for PlanetSide allows us to push the envelope for a 3D engine, tailoring it specifically for the scope of the game.
