public AStarState Create(Board board, AStarState previousState)
{
int currentScore = wrongPlacesHeuristicScoreComputer.Compute(board);
int previousScore = previousState?.TotalHeuristicScore ?? 0;
int totalScore = previousScore + currentScore;
return(new AStarState(board, previousState, currentScore, totalScore));
}
public AStarState(AStarState <Node> copy)
{
open = new HashSet <Node>(copy.open);
closed = new HashSet <Node>(copy.closed);
gs = new Dictionary <Node, float>(copy.gs);
fs = new Dictionary <Node, float>(copy.fs);
previous = new Dictionary <Node, Node>(copy.previous);
current = copy.current;
finished = copy.finished;
}
public void AStarPathSync()
{
AStarState <Point> state = new AStarState <Point>();
state.Start = new Point(4, 2);
state.EndPoints.Add(new Point(5, 15));
var astar = new AStar <Point>(new FakeMap());
astar.FindPathSync(state);
// two steps to the left to get to (2, 2)
// 13 steps down to get to (2, 15)
// 3 steps to the right to get to (5, 15)
// that's 18 steps, plus the start point makes 19.
state.Path.Count.Should().Be(19);
}
public IEnumerable <Point> GetAvailableSteps(AStarState <Point> task, Point location)
{
for (int j = -1; j <= 1; j++)
{
for (int i = -1; i <= 1; i++)
{
if (i == j || i == -j)
{
continue;
}
Point trial = new Point(location.X + i, location.Y + j);
if (IsAvailable(trial))
{
yield return(trial);
}
}
}
}
static void DebugGoap(AStarState <Node> state)
{
var candidate = state.current;
U.Log("OPEN SET " + state.open.Aggregate("", (a, x) => a + x.ToString() + "\n\n"));
U.Log("CLOSED SET " + state.closed.Aggregate("", (a, x) => a + x.ToString() + "\n\n"));
U.Log("CHOSEN CANDIDATE COST " + state.fs[candidate] + ":" + candidate.ToString());
if (state is AStarState <GOAPState> )
{
U.Log("SEQUENCE FOR CANDIDATE" +
U.Generate(state.current, n => state.previous[n])
.TakeWhile(x => x != null)
.Reverse()
.Select(x => x as GOAPState)
.Where(x => x != null && x.generatingAction != null)
.Aggregate("", (a, x) => a + "-->" + x.generatingAction.name)
);
var prevs = state.previous as Dictionary <GOAPState, GOAPState>;
U.Log("Other candidate chains:\n"
+ prevs
.Select(kv => kv.Key)
.Where(y => !prevs.ContainsValue(y))
.Aggregate("", (a, y) => a +
U.Generate(y, n => prevs[n])
.TakeWhile(x => x != null)
.Reverse()
.Select(x => x as GOAPState)
.Where(x => x != null && x.generatingAction != null)
.Aggregate("", (a2, x) => a2 + "-->" + x.generatingAction.name + "(" + x.step + ")")
+ " (COST: g" + (state.gs)[y as Node] + " f" + state.fs[y as Node] + ")"
+ "\n"
)
);
}
}
//expand can return null as "no neighbours"
public static IEnumerable <Node> Run
(
Node from,
Node to,
Func <Node, Node, float> h, //Current, Goal -> Heuristic cost
Func <Node, bool> satisfies, //Current -> Satisfies
Func <Node, IEnumerable <Arc> > expand //Current -> (Endpoint, Cost)[]
)
{
var initialState = new AStarState <Node>();
initialState.open.Add(from);
initialState.gs[from] = 0;
initialState.fs[from] = h(from, to);
initialState.previous[from] = null;
initialState.current = from;
var state = initialState;
while (state.open.Count > 0 && !state.finished)
{
//Debugger gets buggy af with this, can't watch variable:
state = state.Clone();
var candidate = state.open.OrderBy(x => state.fs[x]).First();
state.current = candidate;
//DebugGoap(state);
if (satisfies(candidate))
{
U.Log("SATISFIED");
state.finished = true;
}
else
{
state.open.Remove(candidate);
state.closed.Add(candidate);
var neighbours = expand(candidate);
if (neighbours == null || !neighbours.Any())
{
continue;
}
var gCandidate = state.gs[candidate];
foreach (var ne in neighbours)
{
if (ne.endpoint.In(state.closed))
{
continue;
}
var gNeighbour = gCandidate + ne.cost;
state.open.Add(ne.endpoint);
if (gNeighbour > state.gs.DefaultGet(ne.endpoint, () => gNeighbour))
{
continue;
}
state.previous[ne.endpoint] = candidate;
state.gs[ne.endpoint] = gNeighbour;
state.fs[ne.endpoint] = gNeighbour + h(ne.endpoint, to);
}
}
}
if (!state.finished)
{
return(null);
}
//Climb reversed tree.
var seq =
U.Generate(state.current, n => state.previous[n])
.TakeWhile(n => n != null)
.Reverse();
return(seq);
}
public void ReportProgress(AStarState <Point> task)
{
}
public static IEnumerator Run
(
Node start,
Func <Node, float> heuristic,
Func <Node, bool> satisfies,
Func <Node, IEnumerable <NodeCost> > expand,
Action <IEnumerable <Node> > callback
)
{
var initialState = new AStarState <Node>();
initialState.open.Add(start);
initialState.gs[start] = 0;
initialState.fs[start] = heuristic(start);
initialState.previous[start] = null;
initialState.current = start;
var state = initialState;
while (state.open.Count > 0 && !state.finished)
{
state = state.Clone();
var candidate = state.open.OrderBy(x => state.fs[x]).First();
state.current = candidate;
if (satisfies(candidate))
{
state.finished = true;
}
else
{
state.open.Remove(candidate);
state.closed.Add(candidate);
var neighbours = expand(candidate);
if (neighbours == null || !neighbours.Any())
{
continue;
}
var gCandidate = state.gs[candidate];
foreach (var neighbour in neighbours)
{
if (neighbour.endpoint.In(state.closed))
{
continue;
}
var gNeighbour = gCandidate + neighbour.cost;
state.open.Add(neighbour.endpoint);
if (gNeighbour > state.gs.DefaultGet(neighbour.endpoint, () => gNeighbour))
{
continue;
}
state.previous[neighbour.endpoint] = candidate;
state.gs[neighbour.endpoint] = gNeighbour;
state.fs[neighbour.endpoint] = gNeighbour + heuristic(neighbour.endpoint);
}
}
yield return(null);
}
if (!state.finished)
{
callback(null);
}
else
{
var seq =
AStarUtility.Generate(state.current, n => state.previous[n])
.TakeWhile(n => n != null)
.Reverse();
callback(seq);
}
}
