public int h(Heuristic heuristic, State state)
{
var value = 0;
// How often should we recalculate matching? For now it's once.
if (matching == null)
{
matching = GreedyMinmatching.FindMatching(state, heuristic.DistancesToGoal);
}
// How many goals are left?
foreach (var(box, goal) in matching)
{
if (goal == goalToPrioritize)
{
continue;
}
if (state.BoxesPositions.ContainsKey(box))
{
var boxPosition = state.BoxesPositions[box];
value += heuristic.DistancesToGoal[goal][boxPosition.X, boxPosition.Y];
}
}
// Is box goal or normal goal?
if (goalToPrioritize.IsBoxGoal)
{
var boxForGoal = goalToPrioritize.BoxForGoal;
if (state.BoxesPositions.ContainsKey(boxForGoal))
{
var boxPosition = state.BoxesPositions[boxForGoal];
value += state.AgentPosition.GetManhattanDistanceTo(boxPosition);
}
}
else
{
var boxForGoal = goalToPrioritize.BoxForGoal;
// If there is no box in the boxes positions, then
// that means we already matched it to the goal and removed it.
// So we don't want to increase the heuristic for that case.
if (state.BoxesPositions.ContainsKey(boxForGoal))
{
var boxPosition = state.BoxesPositions[boxForGoal];
var distanceToGoal = heuristic.DistancesToGoal[goalToPrioritize];
value += state.AgentPosition.GetManhattanDistanceTo(boxPosition);
value += distanceToGoal[boxPosition.X, boxPosition.Y];
}
}
return(value);
}
public int h(Heuristic heuristic, State state)
{
var distancesToGoal = heuristic.DistancesToGoal;
var value = 0;
// How often should we recalculate matching? For now it's once.
if (matching == null)
{
matching = GreedyMinmatching.FindMatching(state, distancesToGoal);
}
// Distance from the agent to not matched boxes
foreach (var(agent, agentPosition) in state.AgentsPositions)
{
foreach (var(box, boxPosition) in state.BoxesPositions)
{
// If the agent can't move the box
if (agent.Color != box.Color)
{
continue;
}
// If the box doesn't have a goal or is already on the goal position
if (!matching.ContainsKey(box) || matching[box].Position.Equals(boxPosition))
{
continue;
}
value += agentPosition.GetManhattanDistanceTo(boxPosition);
}
}
// Make agent-boxes distance heuristic less important than boxes-goals distance heuristic
// value /= 2;
// Distances from boxes to goals from the matching
foreach (var(box, goal) in matching)
{
var boxPosition = state.BoxesPositions[box];
value += distancesToGoal[goal][boxPosition.X, boxPosition.Y];
}
return(value);
}