/// <summary>
/// This method tries to change the state the FSM is in based on
/// the current state and the transition passed. If current state
/// doesn't have a target state for the transition passed,
/// an ERROR message is printed.
/// </summary>
public void PerformTransition(int trans)
{
// Check for NullTransition before changing the current state
if (trans == DCFSMState.common_none_trans)
{
Debug.LogError("FSM ERROR: NullTransition is not allowed for a real transition");
return;
}
// Check if the currentState has the transition passed as argument
var id = currentState.GetOutputState(trans);
if (id == DCFSMState.common_none_state)
{
Debug.LogError("FSM ERROR: State " + currentStateID.ToString() + " does not have a target state " +
" for transition " + trans.ToString());
return;
}
// Update the currentStateID and currentState
currentStateID = id;
if (states.TryGetValue(id, out var state))
{
// Do the post processing of the state before setting the new one
currentState.DoBeforeLeaving();
currentState = state;
//如果栈里面已经有这个状态，删除这个状态
Toolkit.RemoveFromStack(mStateStack, currentState);
//加到状态栈
mStateStack.Push(currentState);
// Reset the state to its desired condition before it can reason or act
currentState.DoBeforeEntering();
}
}
