跺地震波：一圈圈踉跄往外推

fx-stomp

local QuakeStomp = {}
local CONST = { MSG_ID = 12350, KEY = "QuakeStomp", WAVE_SPD = 380, BAND = 26 }

function QuakeStomp.Cast(casterID)
    QuakeStomp._x = SL:GetValue("ACTOR_POSITION_X", casterID)
    QuakeStomp._y = SL:GetValue("ACTOR_POSITION_Y", casterID)
    QuakeStomp._waves = { { r = 20 } }                  -- 可多环并存
    QuakeStomp._sched = SL:Schedule(function(dt)
        QuakeStomp:Update(dt)
    end, 0.02)
end

function QuakeStomp:Update(dt)
    local alive = false
    for _, w in ipairs(self._waves or {}) do
        w.r = w.r + CONST.WAVE_SPD * dt                 -- 波前推进
        alive = true
        for _, id in ipairs(SL:GetValue("FIND_IN_VIEW_MONSTER_LIST") or {}) do
            if not w.hit[id] then
                local mx = SL:GetValue("ACTOR_POSITION_X", id)
                local my = SL:GetValue("ACTOR_POSITION_Y", id)
                local dist = math.sqrt((mx - self._x) ^ 2 + ((my - self._y) / 0.5) ^ 2)
                if math.abs(dist - w.r) <= CONST.BAND then
                    w.hit[id] = true
                    SL:SendLuaNetMsg(CONST.MSG_ID, id, 0, 0,
                        SL:JsonEncode({ key = CONST.KEY, op = 2, hit = id }))
                end
            end
        end
    end
    if not alive then SL:UnSchedule(self._sched); self._sched = nil end
end

return QuakeStomp