gmod auto prop save for multiplayer and singleplayer (no owned prop system like ffp)

sv_autosave.lua

local function saveentities()
	local tbl = {}
	local filepos = Format("_savefilemap_%s.txt", game.GetMap())
	for k, v in pairs(ents.FindByClass("prop_physics")) do
		if v:MapCreationID() != -1 then continue end
		table.insert(tbl, {v:GetModel(), v:GetPos(), v:GetAngles(), v:GetMaterial()})
	end
	local tbltxt = util.TableToJSON(tbl)
	file.Write(filepos,tbltxt)
	MsgC(Color(50,255,50), "Wrote " ,Color(100,100,255), tostring(#tbl), Color(50,255,50), " props in file : ", filepos, "\n")
end

local function restoreentities()
	local i = 0
	local filepos = Format("_savefilemap_%s.txt", game.GetMap())
	if not file.Exists(filepos,"DATA") then return false end
	local txt = file.Read(filepos, "DATA")
	local tbl = util.JSONToTable(txt)
	for k, v in ipairs(tbl) do
		local tmpent = ents.Create("prop_physics")
		tmpent:SetModel(v[1])
		tmpent:SetPos(v[2])
		tmpent:SetAngles(v[3])
		tmpent:SetSolid(SOLID_VPHYSICS)
		tmpent:PhysicsInit(SOLID_VPHYSICS)
		if IsValid(tmpent:GetPhysicsObject()) then
			tmpent:GetPhysicsObject():EnableMotion(false)
		else
			i = i +1
			print(Format("missing prop : %s with id %i", v[1], i))

		end
		tmpent:SetMaterial(v[4])
	end
end


hook.Add("InitPostEntity","prop restore lapin",function()
	restoreentities()
	timer.Create("mapsaveprop",60,0,function()
		saveentities()
	end)
end)

concommand.Add("forcesavemap",saveentities)

Drop the file in lua/autorun/server/