public Grid(SolvingGrid g)
{
grid = g.grid;
colorsPresent = g.colors;
pathsOfColors = g.pathsOfColors.ToArray();
RotateFlipPaths(pathsOfColors); // for some weird reason SolvingGrid flips x and y axis (and some other funky stuff, either way this fixes it)
solved = false;
}
/// <summary>
/// Gets the potential directions of the current active cell, or the last cell on the last path in the given SolvingGrid.
/// </summary>
/// <param name="info">All the appropriate info in the form of a SolvingGrid.</param>
/// <returns>Direction array with all options.</returns>
private static Path.Direction[] GetMoveOptions(SolvingGrid info)
{
int Y, X;
Path currentPath = info.pathsOfColors.Last();
Y = currentPath.lastPoint.Y;
X = currentPath.lastPoint.X;
List <Path.Direction> potentials = new List <Path.Direction>();
int[,] grid = info.FlattenGrid();
if (Y - 1 >= 0)
{
if (grid[Y - 1, X] == -1 || // direction is valid if new square is not visited or new square is the endpoint for the color of the current path
new Point(X, Y - 1) == info.endNodes[Array.IndexOf(info.colors, info.pathsOfColors.Last().color)])
{
potentials.Add(Path.Direction.Up);
}
}
if (Y + 1 < grid.GetLength(0))
{
if (grid[Y + 1, X] == -1 ||
new Point(X, Y + 1) == info.endNodes[Array.IndexOf(info.colors, info.pathsOfColors.Last().color)])
{
potentials.Add(Path.Direction.Down);
}
}
if (X - 1 >= 0)
{
if (grid[Y, X - 1] == -1 ||
new Point(X - 1, Y) == info.endNodes[Array.IndexOf(info.colors, info.pathsOfColors.Last().color)])
{
potentials.Add(Path.Direction.Left);
}
}
if (X + 1 < grid.GetLength(1))
{
if (grid[Y, X + 1] == -1 ||
new Point(X + 1, Y) == info.endNodes[Array.IndexOf(info.colors, info.pathsOfColors.Last().color)])
{
potentials.Add(Path.Direction.Right);
}
}
return(potentials.ToArray());
}
public static bool IsItSolvable(int[,] grid, bool filterLameGrids)
{
SolvingGrid info = new SolvingGrid(grid);
if (filterLameGrids) // filters grids that have any two same-color nodes adjacent to each other
{
for (int i = 0; i < info.colors.Length; i++)
{
if ((Math.Abs(info.startNodes[i].X - info.endNodes[i].X) == 1 && info.startNodes[i].Y == info.endNodes[i].Y))
{
return(false);
}
if ((Math.Abs(info.startNodes[i].Y - info.endNodes[i].Y) == 1 && info.startNodes[i].X == info.endNodes[i].X))
{
return(false);
}
}
}
return(Solve(info));
}
/// <summary>
/// Recursive algorithm to solve a level.
/// </summary>
/// <param name="info">All the appropriate info stored in a SolvingGrid.</param>
/// <returns>Returns whether or not the level is solvable.</returns>
private static bool Solve(SolvingGrid info)
{
Path.Direction[] potentials = GetMoveOptions(info);
foreach (Path.Direction d in potentials)
{
info.AddDirectionToCurrentPath(d);
if (info.state == SolvingGrid.SolveState.Success)
{
lastSolution = new Grid(info);
return(true);
}
else if (info.state == SolvingGrid.SolveState.Solving)
{
if (Solve(info))
{
return(true);
}
}
info.RemoveLastAction();
}
return(false);
}