/// <summary>
/// Generates list of textures for given square, when left bottom corner is provided.
/// </summary>
/// <param name="lbx"></param>
/// <param name="lby"></param>
/// <param name="dx"></param>
/// <param name="dy"></param>
/// <returns>Sequence contains textures, starting from left bottom corner and returning rows first.</returns>
public IEnumerable <PointContext> GetWindow(int lbx, int lby, int dx, int dy)
{
for (int y = 0; y < dy; y++)
{
for (int x = 0; x < dx; x++)
{
var geox = lbx + x;
var geoy = lby + y;
var area = new LocationType[9];
var centerOfArea = new GeoPoint(geox, geoy);
for (int i = 0; i < 9; i++)
{
area[i] = LocationType.Water;
}
area[Directions.NeighborTopLeft] = points.ContainsKey(centerOfArea.TopLeft()) ? points[centerOfArea.TopLeft()] : LocationType.Water;
area[Directions.NeighborNorth] = points.ContainsKey(centerOfArea.Top()) ? points[centerOfArea.Top()] : LocationType.Water;
area[Directions.NeighborTopRight] = points.ContainsKey(centerOfArea.TopRight()) ? points[centerOfArea.TopRight()] : LocationType.Water;
area[Directions.NeighborWest] = points.ContainsKey(centerOfArea.Left()) ? points[centerOfArea.Left()] : LocationType.Water;
area[Directions.NeighborThis] = points.ContainsKey(centerOfArea) ? points[centerOfArea] : LocationType.Water;
area[Directions.NeighborEast] = points.ContainsKey(centerOfArea.Right()) ? points[centerOfArea.Right()] : LocationType.Water;
area[Directions.NeighborDownLeft] = points.ContainsKey(centerOfArea.DownLeft()) ? points[centerOfArea.DownLeft()] : LocationType.Water;
area[Directions.NeighborSouth] = points.ContainsKey(centerOfArea.Down()) ? points[centerOfArea.Down()] : LocationType.Water;
area[Directions.NeighborDownRight] = points.ContainsKey(centerOfArea.DownRight()) ? points[centerOfArea.DownRight()] : LocationType.Water;
var centerTexture = new TextureHolder();
var handled = false;
foreach (var strategy in functionStrategies)
{
var texture = strategy(area, centerTexture);
if (texture == centerTexture)
{
continue;
}
centerTexture = texture;
handled = true;
break;
}
if (!handled)
{
foreach (var strategy in strategies)
{
if (!strategy.CanExecute(area))
{
continue;
}
centerTexture = strategy.Execute(area);
handled = true;
break;
}
}
if (!handled)
{
centerTexture = fallbackStrategy.Execute(area);
}
yield return(new PointContext(centerOfArea, centerTexture));
}
}
}