My god Halo, why didn't I think of that before! Forget about contrained joints, springs, friction, gravity, torque, lift, drag, side slip, and center of mass!
Genius!
...
Of course that is assuming the only kind of game you're interested in making is a simulation of Pool or Pong or Asteroids.
And a poor simulation at that.
What happens when your ball is one inch from the wall the frame before it hits it? Hitting the wall stops it, so that frame your ball loses most of it's velocity and slows to stop. That's not right.
The only thing you'd want to subtract current position from previous position for is to determine WHEN a collision occured between frames so that you can then move the ball that extra amount for a slightly more accurate physics simulation.
In practice however, such inaccuracies are unnoticable with simple physics simulations but will cause problems with more complex simulations probably.
Genius!
...
Of course that is assuming the only kind of game you're interested in making is a simulation of Pool or Pong or Asteroids.
And a poor simulation at that.
What happens when your ball is one inch from the wall the frame before it hits it? Hitting the wall stops it, so that frame your ball loses most of it's velocity and slows to stop. That's not right.
The only thing you'd want to subtract current position from previous position for is to determine WHEN a collision occured between frames so that you can then move the ball that extra amount for a slightly more accurate physics simulation.
In practice however, such inaccuracies are unnoticable with simple physics simulations but will cause problems with more complex simulations probably.