【玩法设计】剧情分支存档：选择回看与分支重走的规则设计

local BRANCH = {
    [1] = { opts = 2, desc = "是否放过盗贼" },
    [2] = { opts = 3, desc = "向哪位长老求助" },
}
function saveBranch(actor, point, choice)
    local player = class(actor)
    local mask = tonumber(getplayvar(actor, 2, "STORY_MASK") or "0")
    local shift = (point - 1) * 3
    mask = mask + choice * (2 ^ shift)
    setplayvar(actor, "HUMAN", "STORY_MASK", mask, 1)
    sendmsg(actor, 0, "剧情抉择已记录：" .. BRANCH[point].desc)
end

function rewalkBranch(actor, point, newChoice)
    local player = class(actor)
    local used = tonumber(getplayvar(actor, 2, "REWALK_" .. point) or "0")
    if used >= 1 then
        sendmsg(actor, 0, "该抉择点已重走过1次，无法再次更改")
        return
    end
    if player:checkitemw("回忆卷轴", 1) == false then
        sendmsg(actor, 0, "需要回忆卷轴1张，杂货铺有售3000金币")
        return
    end
    player:takeitem("回忆卷轴", 1)
    setplayvar(actor, "HUMAN", "REWALK_" .. point, 1, 1)
    saveBranch(actor, point, newChoice)
end