public List <PlannerNode <TKey, TValue> > GetNeighbours(PlannerNode <TKey, TValue> _baseNode)
{
m_NeighbourNodes.Clear();
WorldStateModifier <TKey, TValue> basePreconditions = _baseNode.Action?.GetPreconditions();
WorldState <TKey, TValue> worldStateAtBaseNode = _baseNode.GetWorldStateAtNode();
Goal <TKey, TValue> goalWorldStateAtBaseNode = _baseNode.GetGoalWorldStateAtNode();
WorldState <TKey, TValue> remainingGoals = goalWorldStateAtBaseNode - worldStateAtBaseNode;
// We implement regressive A* for GOAP by chaining action preconditions to action effects until all preconditions are fulfilled.
// For this planner, neighbours are nodes that fulfil any of the remaining goals of the base node without conflicting with any of its preconditions.
foreach (IAction <TKey, TValue> possibleAction in m_CurrentAgent.GetActionSet())
{
var effects = possibleAction.GetEffects();
if (!effects.ContainsAny(remainingGoals))
{
continue;
}
if (effects.ConflictsAny(basePreconditions))
{
continue;
}
PlannerNode <TKey, TValue> plannerNode = GetAvailablePlannerNode();
plannerNode.Init(possibleAction);
plannerNode.CalculateWorldStateAtNode(worldStateAtBaseNode);
plannerNode.CalculateGoalWorldStateAtNode(goalWorldStateAtBaseNode);
bool foundInUsed = false;
foreach (PlannerNode <TKey, TValue> usedNode in m_UsedNodes)
{
if (usedNode.Equals(plannerNode))
{
plannerNode = usedNode;
foundInUsed = true;
break;
}
}
m_NeighbourNodes.Add(plannerNode);
if (!foundInUsed)
{
m_UsedNodes.Add(plannerNode);
}
}
return(m_NeighbourNodes);
}
public GoalPlanPair <TKey, TValue> GenerateGoalPlanPairForAgent(IAgent <TKey, TValue> _agent)
{
m_CurrentAgent = _agent;
Stack <PlannerNode <TKey, TValue> > foundPath = null;
bool newGoalBetterThanActiveGoal = false;
m_GoalPlanPair.GoalInstance = null;
m_GoalPlanPair.PlanInstance = null;
for (var goalQueue = m_CurrentAgent.CalculateSortedGoals(); goalQueue.Count > 0;)
{
SortableGoal <TKey, TValue> goal = goalQueue.Dequeue();
PlannerNode <TKey, TValue> agentNode = new PlannerNode <TKey, TValue>();
agentNode.CalculateWorldStateAtNode(_agent.GetWorkingMemory());
agentNode.CalculateGoalWorldStateAtNode(goal);
foundPath = m_Pathfinder.FindPath(agentNode, null);
if (foundPath != null && foundPath.Count > 0)
{
newGoalBetterThanActiveGoal = _agent.IsGoalBetterThanActiveGoal(goal);
if (newGoalBetterThanActiveGoal)
{
m_GoalPlanPair.GoalInstance = goal;
#if UNITY_EDITOR
_agent.CreatePlanHierarchy(foundPath.Last(), m_Pathfinder.GetOpenNodes(), m_Pathfinder.GetClosedNodes());
#endif
}
break;
}
}
m_GoalPlanPair.PlanInstance = new Plan <TKey, TValue>();
if (newGoalBetterThanActiveGoal && foundPath != null)
{
foreach (PlannerNode <TKey, TValue> pathNode in foundPath)
{
if (pathNode.Action != null)
{
m_GoalPlanPair.PlanInstance.Push(pathNode.Action);
}
}
}
m_UsedNodes.Clear();
RecycleUsedNodes();
return(m_GoalPlanPair);
}