For those not in the know (I had to double-check myself), the difference between explicit and semi-implicit Euler is simply the order in which position and velo

For those not in the know (I had to double-check myself), the difference between explicit and semi-implicit Euler is simply the order in which position and velocity are updated. Explicit updates position with the old velocity: particle.position += particle.velocity * dt; particle.velocity += acceleration * dt; Semi-implicit (symplectic) with the new velocity: particle.velocity += acceleration * dt; particle.position += particle.velocity * dt;