Comments by "Crazy Eyes" (@CrizzyEyes) on "Monster Trucking" video.

From experience, I can summarize that coding the actual gravity and moving part is fairly easy, and can actually involve the basic formulas you learn in high school. The collision physics are always the hardest part, in my opinion. And 3D physics are quite literally a dimension's worth more difficult -- not because it's necessarily more complicated per se, but since there's another direction to move in, that's just that much more things you have to check against.
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***** There's only two ways to improve collision physics: run more checks per second, or come up with a better way to check collision. Obviously, the latter is the less-resource intensive, and usually sought after, but it's also much more creatively challenging. Most platformers, for instance, use raycasting, which involves using several long, parallel lines to check for objects that the object is about to touch. This cheapens collision detection because you sort of know that you're going to collide with something ahead of time. It is also a very simple method, so it's usually only good for 2D platformers (at least, in its most pure form).
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***** I meant, an entirely new algorithm or paradigm. Raycasting is probably the most tried-and-true method that results in the tightest 2D platforming (used since games like Mega Man and Mario), but in many 3D games simple bounding box collision is preferred.
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