【网络通信】天梯匹配：段位与延迟的配对算法

---天梯匹配：段位窗随等待扩大
function Ladder.match(actor)
    local player = class(actor)
    if not player then return false end
    local mmr = Ladder.mmrOf(actor)
    local waited = Ladder.waitSecs(actor)
    -- 匹配窗：基础 100 分，每等 10 秒扩 50 分
    local window = 100 + math.floor(waited / 10) * 50
    local opponent = Ladder.findInRange(mmr - window,
        mmr + window, actor)
    if not opponent then
        return false    -- 继续排队
    end
    Ladder.createRoom(actor, opponent)
    return true
end

---胜负的积分结算：Elo 的简化版
function Ladder.settle(actor, opponent, win)
    local player = class(actor)
    if not player then return end
    local mmr = Ladder.mmrOf(actor)
    local opp = Ladder.mmrOf(opponent)
    -- 期望胜率的简化计算
    local expect = 1 / (1 + 10 ^ ((opp - mmr) / 400))
    local delta = math.floor((win and 1 or 0) - expect) * 25
    local newMmr = math.max(0, mmr + delta)
    setplayvar(actor, "HUMAN", "LadderMMR", newMmr, 1)
    sendmsg(actor, 1, (win and "胜利！" or "惜败") ..
        " 积分 " .. (delta >= 0 and "+" or "") .. delta)
end