/// <summary>
///
/// </summary>
/// <param name="size"></param>
/// <returns></returns>
public static IEnumerable<PermutationGroup> Calculate(int size)
{
var source = GetElements(size);
var listPermutation = new List<PermutationGroup>();
listPermutation.Add(new PermutationGroup(new VectorI(Enumerable.Range(0, size).ToArray()), new VectorI[0]));
int length = 0;
var listElements = new List<VectorI[]>();
while (listPermutation.Count() < size.Factorial())
{
length++;
listElements.Clear();
for (int i = 0; i < source.Length; i++)
{
var vector = new VectorI[length];
vector[0] = source[i];
CalculateElements(listElements, source, length, 0, vector);
}
foreach (var elements in listElements)
{
var vector = CalculateVector(size, elements);
if (!listPermutation.Exists(x => x.Vector.Equals(vector)))
{
listPermutation.Add(new PermutationGroup(vector, elements));
}
}
}
return listPermutation;
}
public static void ForEachCellInLine(VectorI lineBegin, VectorI lineEnd, Action <VectorI> action)
{
// from https://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm ("All Cases" section)
var(x, y) = lineBegin;
var dx = Math.Abs(lineEnd.X - x);
var sx = x < lineEnd.X ? 1 : -1;
var dy = -Math.Abs(lineEnd.Y - y);
var sy = y < lineEnd.Y ? 1 : -1;
var error = dx + dy;
while (true)
{
action(new VectorI(x, y));
if (x == lineEnd.X && y == lineEnd.Y)
{
break;
}
var e2 = error + error;
if (e2 >= dy)
{
error += dy;
x += sx;
}
if (e2 <= dx)
{
error += dx;
y += sy;
}
}
}
private void DrawGlyph(VectorI coords)
{
if (!_documentControl.Document.IsInRange(coords))
{
return;
}
_hasDrawn = true;
ref var element = ref _layerEditAccess.GetElementRef(coords);
public ref DocumentElement GetElementRef(VectorI coords)
{
if (coords.X < 0 || coords.Y < 0 || coords.X >= _layer.Width || coords.Y >= _layer.Height)
{
throw new ArgumentOutOfRangeException($"({coords}) are not a valid position in the document.");
}
var(x, y) = coords;
return(ref _layer.Elements[x, y]);
}
protected internal override void OnMouseLeftButtonDown(object sender, MouseEventArgs e)
{
if (_manipulationScope != null)
{
return; // don't know if this ever happens, but it should just continue the current manipulation.
}
_previousDrawPosition = _documentControl.GetDocumentCoordsAt(e.MouseState.Position);
_manipulationScope = _documentControl.Document.Manipulator.BeginManipulation();
_layerEditAccess = _manipulationScope.GetLayerEditAccess(_documentControl.ActiveLayerId);
DrawGlyph(_previousDrawPosition);
}
protected internal override void OnMouseMove(object sender, MouseMoveEventArgs e)
{
if (_manipulationScope == null)
{
return;
}
var documentCoords = _documentControl.GetDocumentCoordsAt(e.MouseState.Position);
GridGeometry.ForEachCellInLine(_previousDrawPosition, documentCoords, DrawGlyph);
_previousDrawPosition = documentCoords;
}
private static VectorI CalculateVector(int size, VectorI[] target)
{
var array = Enumerable.Range(0, size).ToArray();
for (int i = 0; i < target.Length; i++)
{
var temp = array[target[i][0]];
array[target[i][0]] = array[target[i][1]];
array[target[i][1]] = temp;
}
return new VectorI(array);
}
private static void CalculateElements(List<VectorI[]> list, VectorI[] source, int length, int index, VectorI[] vector)
{
if (index == length - 1)
{
var copy = new VectorI[length];
Array.Copy(vector, copy, length);
list.Add(copy);
}
else
{
index++;
for (int i = 0; i < source.Length; i++)
{
vector[index] = source[i];
CalculateElements(list, source, length, index, vector);
}
}
}
private PermutationGroup(VectorI vector, VectorI[] elements)
{
this.Vector = vector;
this.Elements = elements;
}
public static IObservable<PermutationGroup> CalculateEx(int size)
{
var result = Observable.Create<PermutationGroup>(observer =>
{
PermutationGroup pg = null;
var source = GetElements(size);
var listPermutation = new List<PermutationGroup>();
pg = new PermutationGroup(new VectorI(Enumerable.Range(0, size).ToArray()), new VectorI[0]);
listPermutation.Add(pg);
observer.OnNext(pg);
int length = 0;
int maxSize = size.Factorial();
var listElements = new List<VectorI[]>();
while (listPermutation.Count() < maxSize)
{
length++;
listElements.Clear();
for (int i = 0; i < source.Length; i++)
{
var vector = new VectorI[length];
vector[0] = source[i];
CalculateElements(listElements, source, length, 0, vector);
}
foreach (var elements in listElements)
{
var vector = CalculateVector(size, elements);
if (listPermutation.Where(x => x.Vector.Equals(vector)).Count() == 0)
{
pg = new PermutationGroup(vector, elements);
listPermutation.Add(pg);
observer.OnNext(pg);
if (listPermutation.Count() == maxSize)
{
break;
}
}
}
}
observer.OnCompleted();
return () => { };
});
return result;
}
public override bool InHitArea(BattleGrid grid, BattleUnit unit, VectorI target, VectorI tile)
{
return(true);
}
public override bool InRange(BattleGrid grid, BattleUnit unit, VectorI target)
{
return(true);
}