Function smoothSlide

smoothSlide(
    current: number,
    velocity: number,
    smoothTime: number,
    deltaTime: number,
): [number, number]
Smoothens a current value based on velocity while reducing the velocity.
Parameters
- current: number
  the current value
- velocity: number
  the current velocity of the value
- smoothTime: number
  the time it should take to smoothen the velocity to 0
- deltaTime: number
  the amount of time passed since last frame
Returns [number, number]
the smoothened value and new velocity: [position, velocity]