static (int, int) SimulateWithAdjecency(Matrix2D <char> matrix, Func <int, int, Matrix2D <char>, int[]> adjacencyFunc = null, int crowdedThreshold = 4, bool output = false)
{
if (adjacencyFunc == null)
{
adjacencyFunc = FindImmediateNeighbours;
}
int[] indices = new int[128 * 128]; //max 128*128
int[][] adjacencyLists = new int[128 * 128][]; //max 128*128
for (int y = 0; y < matrix.Height; y++)
{
for (int x = 0; x < matrix.Width; x++)
{
int index = (y << 7) + x;
var ptr = matrix.GetIndex(x, y);
indices[index] = ptr;
adjacencyLists[index] = adjacencyFunc(x, y, matrix);
}
}
var current = matrix;
var next = matrix.Clone();
int numFlipped = 1;
int iterations = 0;
while (numFlipped > 0)
{
numFlipped = 0;
for (int y = 0; y < matrix.Height; y++)
{
for (int x = 0; x < matrix.Width; x++)
{
int index = (y << 7) + x;
var adjacency = adjacencyLists[index];
if (adjacency == null)
{
continue; //null or floor
}
var ptr = indices[index];
var c = current.Array[ptr];
if (c == 'L' && IsClear(adjacency, current))
{
next.Array[ptr] = '#';
numFlipped++;
}
else if (c == '#' && IsCrowded(adjacency, current, crowdedThreshold))
{
next.Array[ptr] = 'L';
numFlipped++;
}
else
{
next.Array[ptr] = current.Array[ptr];
}
}
}
if (output)
{
Console.CursorLeft = 0;
Console.CursorTop = 0;
next.Dump();
Thread.Sleep(50);
}
//bufferswap
var tmp = current;
current = next;
next = tmp;
iterations++;
}
return(current.Array.Count(c => c == '#'), iterations);
}