Real-Time Physics Simulation Forum

I was wondering if someone could tell me what are the Ordinary Differential Equations Bullet Physics uses for Rigid Bodies and where they are in the code. Could someone also tell me what numerical methods are used by Bullet Physics to solve it like Runge Kutta and where it is located in the code? I would like to test out another numerical method and compare it to what Bullet Physics is currently using. Any help would be greatly appreciated. Thank you so much!

The ODEs are mildly simplified - rotation ignores the gyroscopic/Coreolis effect (whatever it's called).

The numerical method is Symplectic Euler. This could be a big discussion, but based on the number of people who have tried different integration schemes, it's likely a waste of your time to try improving upon it. I know because I did the same thing.

I don't know where any of it is in the code.

Thank you so much! Knowing that it is symplectic Euler helps a lot. I am still not sure what the Ordinary Differential Equations are and was wondering if someone here knows what they are.