private static bool ExpandConnection(PositionedConnection conn, char[,] artChars)
{
Position currentPos = conn.track[conn.track.Count - 1];
List <Position.Direction> dirs = new List <Position.Direction>();
foreach (var direction in PositionedConnection.GetContainedDirections(conn.tailDirection))
{
Position newPos = currentPos + direction;
if (newPos.IsWithin(artChars))
{
Position.Direction thisDir = CharFits(artChars[newPos.x, newPos.y], direction);
if (thisDir != Position.Direction.None)
{
dirs.Add(direction);
}
}
}
if (dirs.Count == 0)
{
throw new InvalidOperationException("Connection reaches dead end");
}
if (dirs.Count > 1)
{
throw new InvalidOperationException("Connection reaches splitting point: not allowed");
}
Position newPoint = currentPos + dirs[0];
conn.track.Add(newPoint);
conn.tailDirection = CharFits(artChars[newPoint.x, newPoint.y], dirs[0]);
return(!TailAtEnd(artChars[newPoint.x, newPoint.y]));
}
private static Position.Direction CharFits(char found, Position.Direction direction)
{
if (found == '+' || found == '#')
{
switch (direction)
{
case Position.Direction.North:
return(Position.Direction.East | Position.Direction.West | Position.Direction.North);
case Position.Direction.East:
return(Position.Direction.North | Position.Direction.East | Position.Direction.South);
case Position.Direction.South:
return(Position.Direction.East | Position.Direction.West | Position.Direction.South);
case Position.Direction.West:
return(Position.Direction.West | Position.Direction.North | Position.Direction.South);
default: return(Position.Direction.None);
}
}
if (found == '|')
{
switch (direction)
{
case Position.Direction.North:
return(Position.Direction.North);
case Position.Direction.South:
return(Position.Direction.South);
default:
return(Position.Direction.None);
}
}
if (found == '-')
{
switch (direction)
{
case Position.Direction.East:
return(Position.Direction.East);
case Position.Direction.West:
return(Position.Direction.West);
default:
return(Position.Direction.None);
}
}
if (found >= 'a' && found <= 'z')
{
return(direction);
}
if (found >= '0' && found <= '9')
{
return(direction);
}
return(Position.Direction.None);
}
public static IEnumerable <Position.Direction> GetContainedDirections(Position.Direction dir)
{
foreach (var possibleDir in Position.AllDirections)
{
if (possibleDir == Position.Direction.None)
{
continue;
}
if ((dir & possibleDir) == possibleDir)
{
yield return(possibleDir);
}
}
}
private static void ExtractConnectionEndFor(Position pos, char[,] artChars, Position.Direction dir, char pointerSymbol, List <PositionedConnection> pointers)
{
int difX = (dir == Position.Direction.East ? 1 : (dir == Position.Direction.West ? -1 : 0));
int difY = (dir == Position.Direction.South ? 1 : (dir == Position.Direction.North ? -1 : 0));
pos.x += difX; pos.y += difY;
if (pos.x < 0 || pos.y < 0 || pos.x >= artChars.GetLength(0) || pos.y >= artChars.GetLength(1))
{
return;
}
if (artChars[pos.x, pos.y] == pointerSymbol)
{
PositionedConnection newConn = new PositionedConnection()
{
tailDirection = dir
};
newConn.track.Add(pos);
pointers.Add(newConn);
}
}
