Thaumaturge said:
I'm not sure of what remainder there would be
I'll make an example by commenting your code…
def updatePlayer(dt):
newDt = dt
// newDt = 4.01
// someVerySmallValue = 2
while newDt > someVerySmallValue:
# Update both target and camera by a small, fixed increment
position += velocity * someVerySmallValue
updateCamera(someVerySmallValue)
# Keep doing so until the total delta-time for the frame is all-but
# used up
newDt -= someVerySmallValue
// newDt = 0.01 (which i meant with reminder of dt/someVerySmallValue)
# Perform the update one more time, using whatever delta-time remains
// here we integrate this left but small time of 0.01
position += velocity * newDt
updateCamera(newDt)
(btw, i realize i was confused and should not have made the edit to my post, but i got it right initially.)
Now the problem is you integrate those timesteps: 2, 2, 0.01. This can eventually cause problems like motion looking not as smooth as it could be.
Following my proposal you would get: 2.005, 2.005. Which should end up more smooth.
Thaumaturge said:
One thing that I'll note here is that I'm not applying the division to all objects. For example, enemies do not use the divided time-step.
That's fine of coarse, because enemies are no variables affecting our current subdivision of time, which only depends on player and camera stuff.
Though, you may want to use the same strategy for the whole game, so it behaves more consistent across different HW which might cause different delta times.
It's also possible to do both, like having ‘someVerySmallValue’ at 1/10 for the games physics which are not very sensitive on dt, but having it at 1/100 for the camera because it is very sensitive. (just to make some random example)
And if you did this, it could end up recursive eventually, like slicing the whole game by 1/10, which calls the camera update, which slices at 1/100.
In such case a small timestep from a reminder would propagate down to subroutines and cause problems much more likely. Thus i always do the proposed rounding for such things.
