public WumpusActionsFunction(WumpusCave cave)
{
this.cave = cave;
}
/**
* Returns a sequence of actions using A* Search.
*
* @param current
* the agent's current position
* @param goals
* a set of squares; try to plan a route to one of them
* @param allowed
* a set of squares that can form part of the route
*
* @return the best sequence of actions that the agent have to do to reach a
* goal from the current position.
*/
public ICollection <IAction> planRoute(AgentPosition current, ISet <Room> goals, ISet <Room> allowed)
{
// Every square represent 4 possible positions for the agent, it could
// be in different orientations. For every square in allowed and goals
// sets we add 4 squares.
ISet <AgentPosition> allowedPositions = CollectionFactory.CreateSet <AgentPosition>();
foreach (Room allowedRoom in allowed)
{
int x = allowedRoom.getX();
int y = allowedRoom.getY();
allowedPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_WEST));
allowedPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_EAST));
allowedPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_NORTH));
allowedPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_SOUTH));
}
ISet <AgentPosition> goalPositions = CollectionFactory.CreateSet <AgentPosition>();
foreach (Room goalRoom in goals)
{
int x = goalRoom.getX();
int y = goalRoom.getY();
goalPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_WEST));
goalPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_EAST));
goalPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_NORTH));
goalPositions.Add(new AgentPosition(x, y, AgentPosition.Orientation.FACING_SOUTH));
}
WumpusCave cave = new WumpusCave(kb.getCaveXDimension(), kb.getCaveYDimension(), allowedPositions);
GoalTest <AgentPosition> goalTest = goalPositions.Contains;
IProblem <AgentPosition, IAction> problem = new GeneralProblem <AgentPosition, IAction>(current,
WumpusFunctionFunctions.createActionsFunction(cave),
WumpusFunctionFunctions.createResultFunction(), goalTest);
IToDoubleFunction <Node <AgentPosition, IAction> > h = new ManhattanHeuristicFunction(goals);
ISearchForActions <AgentPosition, IAction> search = new AStarSearch <AgentPosition, IAction>(
new GraphSearch <AgentPosition, IAction>(), h);
SearchAgent <AgentPosition, IAction> agent;
ICollection <IAction> actions = null;
try
{
agent = new SearchAgent <AgentPosition, IAction>(problem, search);
actions = agent.getActions();
// Search agent can return a NoOp if already at goal,
// in the context of this agent we will just return
// no actions.
if (actions.Size() == 1 && actions.Get(0).IsNoOp())
{
actions = CollectionFactory.CreateQueue <IAction>();
}
}
catch (Exception e)
{
throw e;
}
return(actions);
}
public static IActionsFunction <AgentPosition, IAction> createActionsFunction(WumpusCave cave)
{
return(new WumpusActionsFunction(cave));
}
