private void PlaceGatesAndTowers(IEnumerable <Vector2> allowedTowerPositions, int minNumberOfGates, int maxNumberOfGates, List <Vector2> illegalGatePositions)
{
var cityPatches = _town.Patches.Where(p => p.WithinCity).ToList();
var outsidePatches = _town.Patches.Except(cityPatches).ToList();
var possibleGates = allowedTowerPositions
.Where(v => cityPatches.Count(cp => cp.Shape.Vertices.Contains(v)) > 1)
.Except(illegalGatePositions)
.OrderByDescending(v => (_town.Castle.Patch.Center - v).Length)
.ToList();
var towers = Circumference.ToList();
var gates = new List <Vector2>();
var attempts = 0;
while ((gates.Count < minNumberOfGates || attempts < 4) && possibleGates.Any() && gates.Count < maxNumberOfGates)
{
attempts++;
var newGate = possibleGates.First();
try
{
possibleGates.Remove(newGate);
possibleGates.RemoveFirstIfPossible();
possibleGates.RemoveFirstIfPossible();
var outerNeighbours = outsidePatches
.Where(p => p.Shape.Vertices.Any(v => v.Equals(newGate)))
.ToList();
if (outerNeighbours.Count == 1)
{
var neighbour = outerNeighbours.Single();
var wallPoint = neighbour.Shape.GetNextVertex(newGate) -
neighbour.Shape.GetPreviousVertex(newGate);
var outPoint = new Vector2(wallPoint.y, -wallPoint.x);
var possibleSplitPoints = neighbour.Shape.Vertices.Except(Circumference).ToList();
var farthest = possibleSplitPoints.OrderByDescending(p =>
{
var dir = p - newGate;
return(Vector2.Dot(dir, outPoint) / dir.Length);
}).First();
var newPatches = neighbour.Shape.Split(newGate, farthest).Select(p => Patch.FromPolygon(_town, p)).ToList();
if (newPatches.Any(p => p.Shape.Vertices.Count < 3))
{
farthest = neighbour.Shape.GetNextVertex(farthest);
newPatches = neighbour.Shape.Split(newGate, farthest).Select(p => Patch.FromPolygon(_town, p)).ToList();
if (newPatches.Any(p => p.Shape.Vertices.Count < 3))
{
throw new InvalidOperationException(
"Splitting patch resulted in polygon with only two points");
}
}
_town.Patches.Remove(neighbour);
_town.Patches.AddRange(newPatches);
}
gates.Add(newGate);
towers.Remove(newGate);
}
catch (InvalidOperationException)
{ }
}
_town.Gates.AddRange(gates);
Gates.AddRange(gates);
Towers.AddRange(towers);
}
