【网络通信】区域组播：按地图分组的消息投递

-- 区域组播：成员注册
local player = class(actor)
local multicastGroups = {}
local function joinMulticast(player, mapId)
    local groupName = "MC_" .. mapId
    multicastGroups[groupName] = multicastGroups[groupName] or {}
    multicastGroups[groupName][getbaseinfo(player, 3)] = true
end
local function leaveMulticast(player, mapId)
    local groupName = "MC_" .. mapId
    if multicastGroups[groupName] then
        multicastGroups[groupName][getbaseinfo(player, 3)] = nil
    end
end

-- 区域组播：发送与扇出
local player = class(actor)
local function multicastTo(player, mapId, msgType, content)
    local groupName = "MC_" .. mapId
    local members = multicastGroups[groupName]
    if members == nil then return end
    local cnt = 0
    for name in pairs(members) do
        cnt = cnt + 1
        local mate = class(name)
        if mate then sendmsg(mate, 1, 0, content) end
    end
    sendmsg(player, 1, 0, "组播 " .. msgType .. " 已投递 " .. cnt .. " 人。")
end