俯冲贯日：从天而降的那一记

fx-dive

local Dive = {}
local KEY = { HOVER = 0.35, DIVE_V = 700 }
local st = { phase = "idle", t = 0 }

local function SetState(name)
    st.phase = name
    st.t = 0
end

function Dive.Cast(self_, target)
    if st.phase ~= "idle" then return end
    SetState("jump")
    SL:Schedule(function(dt)
        st.t = st.t + dt
        if st.phase == "jump" then
            -- 抛物线起跳, 0.5 秒到顶
            local k = math.min(1, st.t / 0.5)
            SL:SetActorOffsetY(self_, -180 * math.sin(k * 3.1416))
            SL:SetActorShadow(self_, math.max(0.35, 1 - k * 0.65))
            if k >= 1 then
                SetState("hover")
                SL:PlayFxAt("lock_mark", SL:GetValue("actorX", target),
                                       SL:GetValue("actorY", target) - 100)
            end
        elseif st.phase == "hover" then
            if st.t >= KEY.HOVER then
                SetState("dive")
                local tx, ty = SL:GetValue("actorX", target),
                               SL:GetValue("actorY", target) - 58
                SL:PlayFlyFx("dive_line", SL:GetValue("actorX", self_),
                             SL:GetValue("actorY", self_), tx, ty,
                             KEY.DIVE_V)
            end
        end
    end, 0.016, "diveRun")
end

-- 飞行体到达回调: 俯冲命中
function Dive.OnArrive(self_, target)
    SetState("land")
    SL:SetActorOffsetY(self_, 0)
    SL:SetActorShadow(self_, 1)
    SL:ScreenShake(0.32, 6)
    SL:PlayFxAt("impact_ring", SL:GetValue("actorX", target),
                               SL:GetValue("actorY", target))
    SL:DeductHp(target, 42)
    SL:ShowHitNum(target, 42, "dive")
    SL:PlayActorAct(target, "stuck")
    SL:ScheduleOnce(function() SetState("idle") end, 1.4)
end

return Dive