/// <summary>
/// Checks in what area the node resides.
/// </summary>
/// <param name="x">The node to be checked</param>
public int GetArea(IAreaNode x)
{
for (var index = 0; index < _areas.Count; ++index)
{
if (_areas[index].Contains(x))
{
return(index);
}
}
return(-1);
}
/// <summary>
/// Section grid by generating areas using FloodFill.
/// </summary>
/// <param name="fields">Array forming 2D grid</param>
public void GenerateAreas(IAreaNode[][] fields)
{
_areas.Clear();
var areaNodeSet = new HashSet <IAreaNode>();
_q.Clear();
var index = -1;
foreach (var field in fields)
{
foreach (IAreaNode areaNode1 in field)
{
if (areaNodeSet.Contains(areaNode1))
{
continue;
}
++index;
_areas.Add(new HashSet <IAreaNode>());
_q.Clear();
_q.Enqueue(areaNode1);
while (_q.Count > 0)
{
IAreaNode areaNode2 = _q.Dequeue();
if (areaNodeSet.Contains(areaNode2))
{
continue;
}
if (areaNode2.X > 0 && fields[areaNode2.X - 1][areaNode2.Y].Id == areaNode1.Id)
{
_q.Enqueue(fields[areaNode2.X - 1][areaNode2.Y]);
}
if (areaNode2.Y > 0 && fields[areaNode2.X][areaNode2.Y - 1].Id == areaNode1.Id)
{
_q.Enqueue(fields[areaNode2.X][areaNode2.Y - 1]);
}
if (areaNode2.X < fields.Length - 1 && fields[areaNode2.X + 1][areaNode2.Y].Id == areaNode1.Id)
{
_q.Enqueue(fields[areaNode2.X + 1][areaNode2.Y]);
}
if (areaNode2.Y < fields[areaNode2.X].Length - 1 &&
fields[areaNode2.X][areaNode2.Y + 1].Id == areaNode1.Id)
{
_q.Enqueue(fields[areaNode2.X][areaNode2.Y + 1]);
}
areaNodeSet.Add(areaNode2);
_areas[index].Add(areaNode2);
}
}
}
}
