I've made my own simple physics engines and used linear algebra to do things like projecting from 3d to 2d space. None of it was any good but it was a lot of fu

I've made my own simple physics engines and used linear algebra to do things like projecting from 3d to 2d space. None of it was any good but it was a lot of fun. This was back when I was most comfortable in Java and the performance was horrible. I don't know what methods of collision detection real engines use but Runge–Kutta is not a good option for real time games. I don't know how to do it and make money but I would recommend playing with the math. It's like magic, you setup the formulas and things just start moving on the screen. It was so much fun.