From: http://uk.insider.ign.com/articles/382/382203p1.html

In some games, the distinction between 2D and 3D isn’t important, because if you’re a space marine running around on foot, the z-axis doesn’t matter, you can’t fly anyway. But Descent made full use of its 3D engine, and how. Set inside asteroids and spaceships and other outer space phenomena, it challenged gamers to come to grips with a zero-gravity, full 3D world in which you could easily find yourself upside down, completely turned around, and hopelessly lost. Motion sickness was a common reaction.

But those who learned how to use the joystick and keyboard to navigate the 3D spaces found themselves with a sense of freedom and exhilaration rarely matched even by today’s games. To this day, it drives me crazy to play crappy flight combat sims which don’t give players the complete six degrees of freedom, keeping their ships right side up by forcing the perspective or putting ‘ceilings’ in the sky.

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