/// compare two dynamic states to detect any changes
private bool HasChanged(DynamicState old, DynamicState now)
{
return((Mathf.Abs(old.position.x - now.position.x) > EPSILON) ||
(Mathf.Abs(old.position.y - now.position.y) > EPSILON) ||
(Mathf.Abs(old.velocity.x - now.velocity.x) > EPSILON) ||
(Mathf.Abs(old.velocity.y - now.velocity.y) > EPSILON));
}
/// update the state change info, should be called
/// once per frame
public void CheckForChanges()
{
// always report changes first time
if (theFirstTime)
{
theFirstTime = false;
hasChanged = true;
state = GetState();
return;
}
// in all other cases,
// has the state actually changed?
hasChanged = HasChanged(state, GetState());
// if so, update change info for next time
if (hasChanged)
{
state = GetState();
}
}
/// formulate array of changed dynamic recorder object states
/// for storage with delta compression
private DynamicDeltaState[] RecordDynamicStates(
DynamicRecorder[] dynamics)
{
// how many states have changed?
int numChanged = 0;
for (int i = 0; i < dynamics.Length; i++)
{
dynamics[i].CheckForChanges();
if (dynamics[i].StateHasChanged())
{
numChanged++;
}
}
// record those changes
DynamicDeltaState[] deltas = new DynamicDeltaState[numChanged];
for (int i = 0, j = 0; i < dynamics.Length; i++)
{
if (dynamics[i].StateHasChanged())
{
DynamicState state = dynamics[i].LastState();
deltas[j++] =
new DynamicDeltaState(i, state.position, state.velocity);
}
}
return(deltas);
}
/// set the state from a recording public abstract void SetState(DynamicState state);
/// set the object's state to match this state
public override void SetState(DynamicState state)
{
remote.AddState(state.position, state.velocity);
}
