/// <summary>
/// Only provided constructor needs a iterator block of course
/// </summary>
public Coroutine(IEnumerable <Instruction> source)
{
// Start processing right away
_Source = source;
_StateData = source.GetEnumerator();
_ExecutionState = CoroutineState.Running;
_Subroutine = null;
}
private CoroutineState CreateCoroutineState(Coroutine executingCoroutine)
{
CoroutineState state = new CoroutineState()
{
Coroutine = executingCoroutine,
Enumerator = executingCoroutine.Execute(),
WaitForObject = null
};
return(state);
}
public void Reset()
{
Debug.Assert(_ExecutionState != CoroutineState.Disposed);
// Clean up any subroutine call
// Since we're forgetting about the subroutine,
// We need to make sure and clean it up
if (_Subroutine != null)
{
_Subroutine.Dispose();
_Subroutine = null;
}
// Reset our enumerator
_StateData.Dispose();
_StateData = _Source.GetEnumerator();
// We are running again
_ExecutionState = CoroutineState.Running;
}
public void Dispose()
{
// Clean up
if (_Subroutine != null)
{
_Subroutine.Dispose();
_Subroutine = null;
}
if (_StateData != null)
{
_StateData.Dispose();
_StateData = null;
}
_Source = null;
// Disposing forces us to be "complete"
_ExecutionState = CoroutineState.Disposed;
}
/// <summary>
/// Executes the coroutine until the next yield statement
/// Possibly recursive Update method, it will recurse when iteration on a child terminates for instance,
/// so we don't skip a single frame if we don't need to.
/// </summary>
public void Update()
{
switch (_ExecutionState)
{
case CoroutineState.Running:
{
Debug.Assert(_Subroutine == null);
try
{
if (_StateData.MoveNext())
{
var ret = _StateData.Current;
// Decide what to do based on what the return value is!
if (ret == null || ret is Instructions.NoopInstruction)
{
// Nothing to do, we'll execute the coroutine again next update!
}
else if (ret is Instructions.ResetInstruction)
{
// Reset our enumerator
_StateData.Dispose();
_StateData = _Source.GetEnumerator();
}
else
{
var callInstruction = ret as Instructions.TransferFlowInstruction;
if (callInstruction != null)
{
// The user code says that we should pass execution to a subroutine, and then resume the current coroutine
// set up our child and execute it right away
_Subroutine = callInstruction.ChildNode;
_ExecutionState = CoroutineState.Subroutine;
// Update the subroutine, and if it completes right away, then we should continue execution of THIS coroutine until the next yield instruction
// We'll deal with this recursively
Update();
}
else
{
// Not handled yet
throw new System.Exception("Instruction of type " + ret.GetType().ToString() + " not supported by Coroutine");
}
}
}
else
{
// We reached the end of the enumeration (i.e. the end of the code)
// We could either loop back around (get a new enumerator), or do nothing...
// We'll do nothing by default. Much better to force the user to write
// an infinite loop if that's what they want.
_ExecutionState = CoroutineState.Complete;
}
}
catch (Diagnostics.CoroutineException gex)
{
throw Diagnostics.CoroutineException.MakeException(gex, _StateData);
}
catch (System.Exception ex)
{
throw Diagnostics.CoroutineException.MakeException(ex, _StateData);
}
}
break;
case CoroutineState.Subroutine:
{
Debug.Assert(_StateData != null);
// We have a subroutine we are 'waiting' on, so execute it instead
_Subroutine.Update();
if (_Subroutine.IsComplete())
{
// Clean up the subroutine
_Subroutine.Dispose();
_Subroutine = null;
// Resume THIS coroutine
_ExecutionState = CoroutineState.Running;
// to resume the subroutine properly and handle all the cases, just recurse
Update();
}
}
break;
case CoroutineState.Complete:
{
Debug.Assert(_Subroutine == null);
// Do nothing
}
break;
case CoroutineState.Disposed:
throw new System.Exception("Coroutine has been disposed, and should not be updated again");
default:
throw new System.NotImplementedException("Unhandled coroutine execution state");
}
}
public void Update(float deltaTime)
{
// Dequeue all enqueued coroutines and schedule them after all other coroutines
while (true)
{
if (!enqueuedCoroutines.TryDequeue(out CoroutineState result))
{
break;
}
executingCoroutines.AddLast(result);
}
if (updateThreadID != -1)
{
throw new CoroutineException("Invalid operation; are you calling Update from more than one thread");
}
updateThreadID = Thread.CurrentThread.ManagedThreadId;
executionState.Update(deltaTime, executionState.FrameIndex + 1);
timerTrigger.Update(deltaTime,
(CoroutineState state) => trigerredCoroutines.Enqueue(state)
);
// Also dequeue all trigerred coroutines
while (true)
{
if (!trigerredCoroutines.TryDequeue(out CoroutineState result))
{
break;
}
executingCoroutines.AddLast(result);
}
for (var executingCoroutineNode = executingCoroutines.First; executingCoroutineNode != null;)
{
CoroutineState executingCoroutine = executingCoroutineNode.Value;
var waitObject = executingCoroutine.WaitForObject;
// If we need to poll wait object, this is done here (no notifies)
if (waitObject != null)
{
if (!waitObject.IsComplete)
{
executingCoroutineNode = executingCoroutineNode.Next;
continue;
}
// We check if wait object ended in bad state
if (waitObject.Exception != null)
{
executingCoroutine.Coroutine.SignalException(
new AggregateException("Wait for object threw an exception", waitObject.Exception));
var tempNode = executingCoroutineNode;
executingCoroutineNode = executingCoroutineNode.Next;
tempNode.List.Remove(tempNode);
continue;
}
executingCoroutine.WaitForObject = null;
}
var advanceAction = AdvanceCoroutine(executingCoroutine);
var nextNode = executingCoroutineNode.Next;
switch (advanceAction)
{
case AdvanceAction.Keep:
break;
case AdvanceAction.MoveToWaitForTrigger:
executingCoroutineNode.List.Remove(executingCoroutineNode);
break;
case AdvanceAction.Complete:
executingCoroutineNode.List.Remove(executingCoroutineNode);
break;
}
while (true)
{
if (!trigerredCoroutines.TryDequeue(out CoroutineState result))
{
break;
}
executingCoroutines.AddLast(result);
// Special case, if we are at end, we removed the node, the next node
// points to null when in fact it should point to trigerred coroutine
if (advanceAction == AdvanceAction.MoveToWaitForTrigger ||
advanceAction == AdvanceAction.Complete)
{
if (nextNode == null)
{
nextNode = executingCoroutines.First;
}
}
}
executingCoroutineNode = nextNode;
}
updateThreadID = -1;
}
private AdvanceAction AdvanceCoroutine(CoroutineState executingCoroutine)
{
var coroutine = executingCoroutine.Coroutine;
while (true)
{
// Execute the coroutine's next frame
bool isCompleted;
// We need to lock to ensure cancellation from source does not interfere with frame
lock (coroutine.SyncRoot)
{
// Cancellation can come from outside, as well as completion
if (coroutine.IsComplete)
{
return(AdvanceAction.Complete);
}
try
{
isCompleted = !executingCoroutine.Enumerator.MoveNext();
}
catch (Exception ex)
{
coroutine.SignalException(ex);
return(AdvanceAction.Complete);
}
if (isCompleted)
{
coroutine.SignalComplete(false, null);
return(AdvanceAction.Complete);
}
}
IWaitObject newWait = executingCoroutine.Enumerator.Current;
executingCoroutine.WaitForObject = newWait;
// Special case null means wait to next frame
if (newWait is WaitForSeconds waitForSeconds)
{
// The wait object is set to null, we bypass it and use trigger instead
executingCoroutine.WaitForObject = null;
timerTrigger.AddTrigger(waitForSeconds.WaitTime, executingCoroutine);
return(AdvanceAction.MoveToWaitForTrigger);
}
if (newWait == null)
{
return(AdvanceAction.Keep);
}
else if (newWait is ReturnValue retVal)
{
coroutine.SignalComplete(true, retVal.Result);
return(AdvanceAction.Complete);
}
if (newWait is Coroutine newWaitCoroutine)
{
// If we yield an unstarted coroutine, we add it to this scheduler!
if (newWaitCoroutine.Status == CoroutineStatus.WaitingForStart)
{
StartSubCoroutine(newWaitCoroutine, coroutine);
switch (newWaitCoroutine.Status)
{
case CoroutineStatus.CompletedWithException:
coroutine.SignalException(newWaitCoroutine.Exception);
return(AdvanceAction.Complete);
case CoroutineStatus.Cancelled:
coroutine.SignalException(new OperationCanceledException("Internal coroutine was cancelled"));
return(AdvanceAction.Complete);
}
}
}
if (newWait.IsComplete)
{
// If the wait object is complete, we continue immediatelly (yield does not split frames)
continue;
}
// Check if we get notified for completion, otherwise polling is used
if (newWait is IWaitObjectWithNotifyCompletion withCompletion)
{
withCompletion.RegisterCompleteSignal(
() =>
{
trigerredCoroutines.Enqueue(executingCoroutine);
});
return(AdvanceAction.MoveToWaitForTrigger);
}
return(AdvanceAction.Keep);
}
}
