IEnumerator WaitForPreviousTransition(StateMapping nextState)
{
while (isInTransition)
{
yield return(null);
}
ChangeState(nextState.state);
}
private IEnumerator ChangeToNewStateRoutine(StateMapping newState)
{
destinationState = newState; //Chache this so that we can overwrite it and hijack a transition
if (currentState != null)
{
exitRoutine = currentState.Exit();
if (exitRoutine != null)
{
yield return(StartCoroutine(exitRoutine));
}
exitRoutine = null;
currentState.Finally();
}
currentState = destinationState;
if (currentState != null)
{
enterRoutine = currentState.Enter();
if (enterRoutine != null)
{
yield return(StartCoroutine(enterRoutine));
}
enterRoutine = null;
//Broadcast change only after enter transition has begun.
if (Changed != null)
{
Changed(currentState.state);
}
}
isInTransition = false;
}
public void Initialize <T>(StateBehaviour entity)
{
//Define States
var values = Enum.GetValues(typeof(T));
stateLookup = new Dictionary <Enum, StateMapping>();
for (int i = 0; i < values.Length; i++)
{
var mapping = new StateMapping((Enum)values.GetValue(i));
stateLookup.Add(mapping.state, mapping);
}
//Reflect methods
var methods = entity.GetType().GetMethods(BindingFlags.Instance | BindingFlags.DeclaredOnly | BindingFlags.Public |
BindingFlags.NonPublic);
//Bind methods to states
var separator = "_".ToCharArray();
for (int i = 0; i < methods.Length; i++)
{
var names = methods[i].Name.Split(separator);
//Ignore functions without an underscore
if (names.Length <= 1)
{
continue;
}
Enum key;
try
{
key = (Enum)Enum.Parse(typeof(T), names[0]);
}
catch (ArgumentException)
{
//Some things (evetns, properties) generate automatic method. Ignore these
for (int j = 0; j < ignoredNames.Length; j++)
{
if (names[0] == ignoredNames[j])
{
goto SkipWarning;
}
}
Debug.LogWarning("Method with name " + methods[i].Name + " could not resolve a matching state. Check method spelling");
continue;
SkipWarning:
continue;
}
var targetState = stateLookup[key];
switch (names[1])
{
case "Enter":
if (methods[i].ReturnType == typeof(IEnumerator))
{
targetState.Enter = CreateDelegate <Func <IEnumerator> >(methods[i], entity);
}
else
{
var action = CreateDelegate <Action>(methods[i], entity);
targetState.Enter = () => { action(); return(null); };
}
break;
case "Exit":
if (methods[i].ReturnType == typeof(IEnumerator))
{
targetState.Exit = CreateDelegate <Func <IEnumerator> >(methods[i], entity);
}
else
{
var action = CreateDelegate <Action>(methods[i], entity);
targetState.Exit = () => { action(); return(null); };
}
break;
case "Finally":
targetState.Finally = CreateDelegate <Action>(methods[i], entity);
break;
case "Update":
targetState.Update = CreateDelegate <Action>(methods[i], entity);
break;
case "LateUpdate":
targetState.LateUpdate = CreateDelegate <Action>(methods[i], entity);
break;
case "FixedUpdate":
targetState.FixedUpdate = CreateDelegate <Action>(methods[i], entity);
break;
}
}
}
public void ChangeState(Enum newState, StateTransition transition = StateTransition.Safe)
{
if (stateLookup == null)
{
throw new Exception("States have not been configured, please call initialized before trying to set state");
}
if (!stateLookup.ContainsKey(newState))
{
throw new Exception("No state with the name " + newState.ToString() + " can be found. Please make sure you are called the correct type the statemachine was initialized with");
}
var nextState = stateLookup[newState];
if (currentState == nextState)
{
return;
}
//Cancel any queued changes.
if (queuedChange != null)
{
StopCoroutine(queuedChange);
queuedChange = null;
}
switch (transition)
{
//case StateMachineTransition.Blend:
//Do nothing - allows the state transitions to overlap each other. This is a dumb idea, as previous state might trigger new changes.
//A better way would be to start the two couroutines at the same time. IE don't wait for exit before starting start.
//How does this work in terms of overwrite?
//Is there a way to make this safe, I don't think so?
//break;
case StateTransition.Safe:
if (isInTransition)
{
if (exitRoutine != null) //We are already exiting current state on our way to our previous target state
{
//Overwrite with our new target
destinationState = nextState;
return;
}
if (enterRoutine != null) //We are already entering our previous target state. Need to wait for that to finish and call the exit routine.
{
//Damn, I need to test this hard
queuedChange = WaitForPreviousTransition(nextState);
StartCoroutine(queuedChange);
return;
}
}
break;
case StateTransition.Overwrite:
if (currentTransition != null)
{
StopCoroutine(currentTransition);
}
if (exitRoutine != null)
{
StopCoroutine(exitRoutine);
}
if (enterRoutine != null)
{
StopCoroutine(enterRoutine);
}
if (currentState != null)
{
currentState.Finally();
}
currentState = null; //We need to set current state to null so that we don't trigger it's exit routine
break;
}
isInTransition = true;
currentTransition = ChangeToNewStateRoutine(nextState);
StartCoroutine(currentTransition);
}
