旋风斩：转着走的那几圈

mir8-whirl

function gameActor:StartWhirl(duration)
    if self._whirlT and self._whirlT > 0 then return end
    self._whirlT = duration
    self._spinIdx = 0
    self._tickAcc = 0
    self._moveLocked = true                        -- 旋风期间锁移动
end

function gameActor:UpdateWhirl(dt)
    if not self._whirlT or self._whirlT <= 0 then return end
    self._whirlT = self._whirlT - dt

    self._spinIdx = self._spinIdx + dt * 14        -- 方向帧轮播: 一圈约0.57秒
    self._dir = math.floor(self._spinIdx) % 8

    self._tickAcc = self._tickAcc + dt
    if self._tickAcc >= 0.4 then                   -- 结算节拍: 与环刃同步
        self._tickAcc = self._tickAcc - 0.4
        SpawnWhirlBlades(self._x, self._y, WHIRL_R, WHIRL_FLAT)
        for _, m in ipairs(GetMonstersInEllipse(self, WHIRL_R, WHIRL_FLAT)) do
            m:OnHit(18)
        end
    end

    if self._whirlT <= 0 then
        self._moveLocked = false
        self:PlayAction(global.MMO.ANIM_IDLE)
    end
end