Disable gfMoreWind for land objects on turn end only after a fixed-time delay
15s sounds much, but it's the average amount for gfMineStrike mines to settle
naturally. And it would be very confusing to see falling mines suddenly not
caring about gfMoreWind for no apparent reason.
Note this whole thing is a giant hack anyway, to prevent a turn being
blocked by infinitely bouncing mines.
The better solution would be to help gfMoreWind-affected land objects settle
naturally more reliably even under extreme wind.
But this commit is "good enough" for now.
If you don't like the delay, you can always tweak the constant.
{-
Glicko2, as described in http://www.glicko.net/glicko/glicko2.pdf
-}
module OfficialServer.Glicko2 where
data RatingData = RatingData {
ratingValue
, rD
, volatility :: Double
}
data GameData = GameData {
opponentRating :: RatingData,
gameScore :: Double
}
τ, ε :: Double
τ = 0.2
ε = 0.000001
g_φ :: Double -> Double
g_φ φ = 1 / sqrt (1 + 3 * φ^2 / pi^2)
calcE :: RatingData -> GameData -> (Double, Double, Double)
calcE oldRating (GameData oppRating s) = (
1 / (1 + exp (g_φᵢ * (μᵢ - μ)))
, g_φᵢ
, s
)
where
μ = (ratingValue oldRating - 1500) / 173.7178
φ = rD oldRating / 173.7178
μᵢ = (ratingValue oppRating - 1500) / 173.7178
φᵢ = rD oppRating / 173.7178
g_φᵢ = g_φ φᵢ
calcNewRating :: RatingData -> [GameData] -> (Int, RatingData)
calcNewRating oldRating [] = (0, RatingData (ratingValue oldRating) (173.7178 * sqrt (φ ^ 2 + σ ^ 2)) σ)
where
φ = rD oldRating / 173.7178
σ = volatility oldRating
calcNewRating oldRating games = (length games, RatingData (173.7178 * μ' + 1500) (173.7178 * sqrt φ'sqr) σ')
where
_Es = map (calcE oldRating) games
υ = 1 / sum (map υ_p _Es)
υ_p (_Eᵢ, g_φᵢ, _) = g_φᵢ ^ 2 * _Eᵢ * (1 - _Eᵢ)
_Δ = υ * part1
part1 = sum (map _Δ_p _Es)
_Δ_p (_Eᵢ, g_φᵢ, sᵢ) = g_φᵢ * (sᵢ - _Eᵢ)
μ = (ratingValue oldRating - 1500) / 173.7178
φ = rD oldRating / 173.7178
σ = volatility oldRating
a = log (σ ^ 2)
f :: Double -> Double
f x = exp x * (_Δ ^ 2 - φ ^ 2 - υ - exp x) / 2 / (φ ^ 2 + υ + exp x) ^ 2 - (x - a) / τ ^ 2
_A = a
_B = if _Δ ^ 2 > φ ^ 2 + υ then log (_Δ ^ 2 - φ ^ 2 - υ) else head . dropWhile ((>) 0 . f) . map (\k -> a - k * τ) $ [1 ..]
fA = f _A
fB = f _B
σ' = (\(_A, _, _, _) -> exp (_A / 2)) . head . dropWhile (\(_A, _, _B, _) -> abs (_B - _A) > ε) $ iterate step5 (_A, fA, _B, fB)
step5 (_A, fA, _B, fB) = let _C = _A + (_A - _B) * fA / (fB - fA); fC = f _C in
if fC * fB < 0 then (_B, fB, _C, fC) else (_A, fA / 2, _C, fC)
φ'sqr = 1 / (1 / (φ ^ 2 + σ' ^ 2) + 1 / υ)
μ' = μ + φ'sqr * part1