public static void Initialize()
{
Database.SetInitializer <LevelsContext>(new DropCreateDatabaseAlways <LevelsContext>());
using (var levelsContext = new LevelsContext())
{
int count = levelsContext.Levels.Count();
if (count < MIN_LEVELS)
{
for (int i = count; i < MIN_LEVELS; i++)
{
levelsContext.Levels.Add(GenerateRandomLevel());
}
}
else if (count > MAX_LEVELS)
{
int toRemove = MAX_LEVELS - count;
var levelsToRemove = levelsContext.Levels.OrderBy(level => levelsContext.GetAverageRatingForLevel(level)).Take(toRemove);
levelsContext.Levels.RemoveRange(levelsToRemove);
}
levelsContext.SaveChanges();
}
MaintainThread = new Thread(Maintain);
MaintainThread.Start();
}
/// <summary>
/// This method runs for the life of the program, slowly evolving the level set.
/// </summary>
private static void Maintain()
{
int lastRatingsCount = 0;
while (!IsClosing)
{
Thread.Sleep(1000);
using (var levelsContext = new LevelsContext())
{
int ratingsCount = levelsContext.Ratings.Count();
if (ratingsCount < lastRatingsCount)
{
lastRatingsCount = ratingsCount;
}
if (ratingsCount - lastRatingsCount > 10)
{
const int descendants = 3;
var parents = levelsContext.Levels.OrderByDescending(level => levelsContext.GetAverageRatingForLevel(level)).Take(2 * descendants).ToList();
for (int i = 0; i < descendants * 2; i += 2)
{
Level l1 = parents[i].Level.Mutate(MUTATION_RATE);
Level l2 = parents[i + 1].Level.Mutate(MUTATION_RATE);
Level newLevel = l1.Crossover(l2, CROSSOVER_RATE);
levelsContext.Levels.Add(newLevel);
}
}
lastRatingsCount = ratingsCount;
levelsContext.SaveChanges();
}
}
}