/// <summary>
/// Steps the game one generation into the future.
/// </summary>
public override void StepForward()
{
var deadCells = new List <Cell>();
var newCells = new List <Cell>();
++generation;
if (Population > 0)
{
var currentState = new Universe(universe); // copy the state of the universe
List <Cell> cellsToCheck = currentState.AllCells;
// linq magic, where we check all cells already in the universe
// and also all of their neighbors. since the speed of light is
// 1 in game of life, this is sufficient.
cellsToCheck.AddRange(
from cell in currentState.AllCells
from neighbor in currentState.ListAllPossibleNeighbors(cell.X, cell.Y)
where !cellsToCheck.Contains(neighbor)
select neighbor);
foreach (var cell in cellsToCheck)
{
int numberOfNeighbors = currentState.CountLivingNeighbors(cell.X, cell.Y);
bool aliveNow = currentState.HasCell(cell.X, cell.Y);
bool aliveNext = Rules.AliveNextGeneration(aliveNow, numberOfNeighbors);
if (aliveNow && !aliveNext)
{
universe.Remove(cell);
deadCells.Add(cell);
}
if (!aliveNow && aliveNext)
{
universe.Add(cell);
newCells.Add(cell);
}
}
}
if (GameStepEvent != null)
{
var stepInformation = new GameStepEventArgs(deadCells, newCells);
GameStepEvent(this, stepInformation);
}
}