// PERF: If this ends up being slow, we can mark with a dirty bit
/**
* Returns a path from start to end, exclusive - that is, the start and end nodes are *not* listed in the path. Does a full
* naive search every time.
*/
public static List <EncounterPosition> AStarWithNewGrid(
EncounterPosition start,
EncounterPosition end,
EncounterState state,
int maxAreaToExplore = 950
)
{
SimplePriorityQueue <EncounterPosition> frontier = new SimplePriorityQueue <EncounterPosition>();
frontier.Enqueue(start, 0f);
var cameFrom = new Dictionary <EncounterPosition, EncounterPosition>();
var costSoFar = new Dictionary <EncounterPosition, float>();
costSoFar[start] = 0f;
while (frontier.Count > 0 && cameFrom.Count < maxAreaToExplore)
{
var currentPosition = frontier.Dequeue();
var adjacentPositions = state.AdjacentPositions(currentPosition);
if (currentPosition == end || (state.IsPositionBlocked(end) && adjacentPositions.Contains(end)))
{
var path = new List <EncounterPosition>()
{
currentPosition
};
EncounterPosition cameFromPos;
while (cameFrom.TryGetValue(path[path.Count - 1], out cameFromPos) && (cameFromPos != start))
{
path.Add(cameFromPos);
}
path.Reverse();
return(path);
}
var adjacentUnblocked = adjacentPositions.Where(adjacent => !state.IsPositionBlocked(adjacent)).ToList();
adjacentUnblocked.ForEach(adjacent => {
var newNextPositionCost = costSoFar[currentPosition] + 1f;
if (!costSoFar.ContainsKey(adjacent) || newNextPositionCost < costSoFar[adjacent])
{
costSoFar[adjacent] = newNextPositionCost;
// Uses straight-line distance as heuristic
float priority = newNextPositionCost + adjacent.DistanceTo(end);
frontier.Enqueue(adjacent, priority);
cameFrom[adjacent] = currentPosition;
}
});
}
return(null);
}
private static bool ResolveMove(MoveAction action, EncounterState state)
{
Entity actor = state.GetEntityById(action.ActorId);
var positionComponent = state.GetEntityById(action.ActorId).GetComponent <PositionComponent>();
if (positionComponent.EncounterPosition == action.TargetPosition)
{
GD.PrintErr(string.Format("Entity {0}:{1} tried to move to its current position {2}", actor.EntityName, actor.EntityId, action.TargetPosition));
return(false);
}
else if (state.IsPositionBlocked(action.TargetPosition))
{
var blocker = state.BlockingEntityAtPosition(action.TargetPosition.X, action.TargetPosition.Y);
var actorCollision = actor.GetComponent <CollisionComponent>();
if (actorCollision.OnCollisionAttack)
{
Attack(actor, blocker, state);
}
if (actorCollision.OnCollisionSelfDestruct)
{
state.TeleportEntity(actor, action.TargetPosition, ignoreCollision: true);
if (state.FoVCache.IsVisible(action.TargetPosition))
{
positionComponent.PlayExplosion();
}
ResolveAction(new DestroyAction(action.ActorId), state);
}
return(true);
}
else
{
state.TeleportEntity(actor, action.TargetPosition, ignoreCollision: false);
return(true);
}
}