public override Simulation createBallisticSimulation(ScrollMetrics position, float velocity)
{
D.assert(
position is _FixedExtentScrollPosition,
() => "FixedExtentScrollPhysics can only be used with Scrollables that uses " +
"the FixedExtentScrollController"
);
_FixedExtentScrollPosition metrics = (_FixedExtentScrollPosition)position;
if ((velocity <= 0.0f && metrics.pixels <= metrics.minScrollExtent) ||
(velocity >= 0.0f && metrics.pixels >= metrics.maxScrollExtent))
{
return(base.createBallisticSimulation(metrics, velocity));
}
Simulation testFrictionSimulation =
base.createBallisticSimulation(metrics, velocity);
if (testFrictionSimulation != null &&
(testFrictionSimulation.x(float.PositiveInfinity) == metrics.minScrollExtent ||
testFrictionSimulation.x(float.PositiveInfinity) == metrics.maxScrollExtent))
{
return(base.createBallisticSimulation(metrics, velocity));
}
int settlingItemIndex = ListWheelScrollViewUtils._getItemFromOffset(
offset: testFrictionSimulation?.x(float.PositiveInfinity) ?? metrics.pixels,
itemExtent: metrics.itemExtent,
minScrollExtent: metrics.minScrollExtent,
maxScrollExtent: metrics.maxScrollExtent
);
float settlingPixels = settlingItemIndex * metrics.itemExtent;
if (velocity.abs() < tolerance.velocity &&
(settlingPixels - metrics.pixels).abs() < tolerance.distance)
{
return(null);
}
if (settlingItemIndex == metrics.itemIndex)
{
return(new SpringSimulation(
spring,
metrics.pixels,
settlingPixels,
velocity,
tolerance: tolerance
));
}
return(FrictionSimulation.through(
metrics.pixels,
settlingPixels,
velocity,
tolerance.velocity * velocity.sign()
));
}
public BouncingScrollSimulation(
float position,
float velocity,
float leadingExtent,
float trailingExtent,
SpringDescription spring,
Tolerance tolerance = null
) : base(tolerance: tolerance)
{
D.assert(leadingExtent <= trailingExtent);
D.assert(spring != null);
this.leadingExtent = leadingExtent;
this.trailingExtent = trailingExtent;
this.spring = spring;
if (position < leadingExtent)
{
_springSimulation = _underscrollSimulation(position, velocity);
_springTime = float.NegativeInfinity;
}
else if (position > trailingExtent)
{
_springSimulation = _overscrollSimulation(position, velocity);
_springTime = float.NegativeInfinity;
}
else
{
_frictionSimulation = new FrictionSimulation(0.135f, position, velocity);
float finalX = _frictionSimulation.finalX;
if (velocity > 0.0f && finalX > trailingExtent)
{
_springTime = _frictionSimulation.timeAtX(trailingExtent);
_springSimulation = _overscrollSimulation(
trailingExtent,
Mathf.Min(_frictionSimulation.dx(_springTime),
maxSpringTransferVelocity)
);
D.assert(_springTime.isFinite());
}
else if (velocity < 0.0f && finalX < leadingExtent)
{
_springTime = _frictionSimulation.timeAtX(leadingExtent);
_springSimulation = _underscrollSimulation(
leadingExtent,
Mathf.Min(_frictionSimulation.dx(_springTime),
maxSpringTransferVelocity)
);
D.assert(_springTime.isFinite());
}
else
{
_springTime = float.PositiveInfinity;
}
}
}
void Start()
{
m_initPosition = transform.position;
m_rb = GetComponent <Rigidbody>();
m_initImpulse = GetComponent <InitialImpulse>();
m_launchImpulse = GetComponent <LaunchImpulse>();
m_frictionSim = GetComponent <FrictionSimulation>();
m_soundManager = FindObjectOfType <SoundManager>();
m_frictionSim.enabled = false;
}
