【性能调优】飘字对象池：战斗飘字的复用管理

---飘字的对象池
local pool = {}
local active = {}
function FloatText.spawn(parent, x, y, text, color)
    local widget = table.remove(pool)
    if not widget then
        widget = GUI:Text_Create(parent, "", x, y, 18, color, text)
    else
        widget:setParent(parent)
        widget:setPosition(x, y)
        widget:setTextString(text)
        widget:setColor(color)
        widget:setVisible(true)
    end
    active[#active + 1] = { widget = widget, bornAt = os.clock() }
    return widget
end

---飘字的生命周期：显示 1.5 秒后回收
function FloatText.update(dt)
    local now = os.clock()
    for i = #active, 1, -1 do
        local rec = active[i]
        if now - rec.bornAt > 1.5 then
            rec.widget:setVisible(false)
            table.insert(pool, rec.widget)
            table.remove(active, i)
        end
    end
end