public bool MoveNext()
{
if (!this.initialized)
{
this.position = this.grid.GetCenterPosition();
this.compassCycle = this.compassCycle.Reset();
this.initialized = true;
return(true);
}
if (this.position == this.end)
{
return(false);
}
var compassCycle = this.compassCycle.Next();
var position = this.position.MoveTo(compassCycle.Direction);
if (this.grid.CanPositionBeTaken(position))
{
this.compassCycle = compassCycle;
this.position = position;
}
else
{
this.position = this.position.MoveTo(this.compassCycle.Direction);
}
return(true);
}
public SpiralOutwardGridPositionEnumerator(Grid grid)
{
this.grid = grid ?? throw new ArgumentNullException(nameof(grid));
this.compassCycle = new CompassCycle(Direction.Right, Direction.Up, Direction.Left, Direction.Down);
this.end = new Position(grid.Size - 1, grid.Size - 1);
this.initialized = false;
}
