//----------------------------------------------------------------------------
// Generate Path
//----------------------------------------------------------------------------
#region GeneratePath
/// <summary>
/// Generic A* pathfinding, hex distance as heuristic
/// </summary>
public MapPath GeneratePath(IHexagon hex_a, IHexagon hex_b)
{
SortedSet <IPathValue> openSet = new SortedSet <IPathValue>();
PathValueDict = new Dictionary <IHexagon, IPathValue>();
Start = hex_a;
Destination = hex_b;
IPathValue firstPath = GetPathValue(hex_a);
firstPath.SetFirstPathDistance();
openSet.Add(firstPath);
while (openSet.Count != 0)
{
IPathValue currentPath = openSet.Min;
openSet.Remove(currentPath);
IHexagon currentHex = currentPath.Hex;
if (currentHex.MyHexMap.CoOrds == hex_b.MyHexMap.CoOrds)
{
return(currentPath.ReconstructPath());
}
foreach (IHexagon neighbour in currentHex.MyHexMap.Neighbours)
{
if (!neighbour.MyHexMap.IsOccupied())
{
IPathValue neighbourPath = GetPathValue(neighbour);
int newGScore = currentPath.Score_g + neighbour.MyHexMap.MovementCost;
if (newGScore < neighbourPath.Score_g)
{
if (openSet.Contains(neighbourPath))
{
openSet.Remove(neighbourPath);
}
neighbourPath.UpdateValues(newGScore, currentPath);
openSet.Add(neighbourPath);
}
}
}
}
return(null);
}
//----------------------------------------------------------------------------
// Hexes in Range
//----------------------------------------------------------------------------
/// <summary>
/// This is an almost direct copy of above, but it sets the heuristic distance to
/// to the start location <para/>
///
/// So in practice it is Dijkstra's out until range
/// </summary>
public HashSet <IHexagon> GetHexesInRange(IHexagon start, int range)
{
SortedSet <IPathValue> openSet = new SortedSet <IPathValue>();
HashSet <IHexagon> hexesInRange = new HashSet <IHexagon>();
PathValueDict = new Dictionary <IHexagon, IPathValue>();
Destination = start;
Start = start;
IPathValue firstPath = GetPathValue(start);
firstPath.SetFirstPathDistance();
openSet.Add(firstPath);
while (openSet.Count != 0)
{
IPathValue currentPath = openSet.Min;
openSet.Remove(currentPath);
IHexagon currentHex = currentPath.Hex;
hexesInRange.Add(currentHex);
foreach (IHexagon neighbour in currentHex.MyHexMap.Neighbours)
{
if (!neighbour.MyHexMap.IsOccupied())
{
IPathValue neighbourPath = GetPathValue(neighbour);
int newGScore = currentPath.Score_g + neighbour.MyHexMap.MovementCost;
if (newGScore < neighbourPath.Score_g && newGScore <= range)
{
if (openSet.Contains(neighbourPath))
{
openSet.Remove(neighbourPath);
}
neighbourPath.UpdateValues(newGScore, currentPath);
openSet.Add(neighbourPath);
}
}
}
}
return(hexesInRange);
}
