fixed lua errors and code mistakes

init.lua

@@ -17,3 +17,5 @@ dofile(advtrains.modpath.."/trainhud.lua")
 dofile(advtrains.modpath.."/trackplacer.lua")
 dofile(advtrains.modpath.."/tracks.lua")
 dofile(advtrains.modpath.."/wagons.lua")
+
+dofile(advtrains.modpath.."/pseudoload.lua");

pseudoload.lua

@@ -9,6 +9,9 @@ advtrains.trackdb={}
 --[] may be missing if 0,0,0
 
 --load initially
+--delayed since all traintypes need to be registered
+minetest.after(0, function()
+
 for tt, _ in pairs(advtrains.all_traintypes) do
 	local pl_fpath=minetest.get_worldpath().."/advtrains_trackdb_"..tt
 	advtrains.trackdb[tt]={}
@@ -59,6 +62,8 @@ for tt, _ in pairs(advtrains.all_traintypes) do
 	end
 end
 
+--end minetest.after
+end)
 
 function advtrains.save_trackdb()
 	for tt, _ in pairs(advtrains.all_traintypes) do
@@ -99,8 +104,8 @@ function advtrains.get_rail_info_at(pos, traintype)
 	local node=minetest.get_node_or_nil(pos)
 	if not node then
 		--try raildb
-		local rdp=vector.round(rdp)
-		local dbe=advtrains.trackdb[traintype][rdp.y][rdp.x][rdp.z]
+		local rdp=vector.round(pos)
+		local dbe=(advtrains.trackdb[traintype] and advtrains.trackdb[traintype][rdp.y] and advtrains.trackdb[traintype][rdp.y][rdp.x] and advtrains.trackdb[traintype][rdp.y][rdp.x][rdp.z])
 		if dbe then
 			return true, dbe.conn1, dbe.conn2, dbe.rely1 or 0, dbe.rely2 or 0, dbe.railheight or 0
 		else
@@ -114,9 +119,12 @@ function advtrains.get_rail_info_at(pos, traintype)
 	local conn1, conn2, rely1, rely2, railheight=advtrains.get_track_connections(node.name, node.param2)
 	
 	--already in trackdb?
-	local rdp=vector.round(rdp)
-	if not advtrains.trackdb[traintype][rdp.y][rdp.x][rdp.z] then--TODO is this necessary?
-		advtrains.trackdb[rdp.y][rdp.x][rdp.z]={
+	local rdp=vector.round(pos)
+	if not (advtrains.trackdb[traintype] and advtrains.trackdb[traintype][rdp.y] and advtrains.trackdb[traintype][rdp.y][rdp.x] and advtrains.trackdb[traintype][rdp.y][rdp.x][rdp.z]) then--TODO is this necessary?
+		if not advtrains.trackdb[traintype] then advtrains.trackdb[traintype]={} end
+		if not advtrains.trackdb[traintype][rdp.y] then advtrains.trackdb[traintype][rdp.y]={} end
+		if not advtrains.trackdb[traintype][rdp.y][rdp.x] then advtrains.trackdb[traintype][rdp.y][rdp.x]={} end
+		advtrains.trackdb[traintype][rdp.y][rdp.x][rdp.z]={
 			conn1=conn1, conn2=conn2,
 			rely1=rely1, rely2=rely2,
 			railheight=railheight
@@ -128,6 +136,9 @@ end
 function advtrains.reset_trackdb_position(pos)
 	local rdp=vector.round(pos)
 	for tt, _ in pairs(advtrains.all_traintypes) do
+		if not advtrains.trackdb[tt] then advtrains.trackdb[tt]={} end
+		if not advtrains.trackdb[tt][rdp.y] then advtrains.trackdb[tt][rdp.y]={} end
+		if not advtrains.trackdb[tt][rdp.y][rdp.x] then advtrains.trackdb[tt][rdp.y][rdp.x]={} end
 		advtrains.trackdb[tt][rdp.y][rdp.x][rdp.z]=nil
 		advtrains.get_rail_info_at(pos, tt)--to restore it.
 	end

tracks.lua

@@ -74,10 +74,10 @@ function advtrains.register_tracks(tracktype, def)
 		after_dig_node=function(pos)
 			advtrains.invalidate_all_paths()
 			advtrains.reset_trackdb_position(pos)
-		end
+		end,
 		after_place_node=function(pos)
 			advtrains.reset_trackdb_position(pos)
-		end
+		end,
 	}
 	minetest.register_node(def.nodename_prefix.."_st", advtrains.merge_tables(common_def, make_overdef("st", 0, 4), def.straight or {}))
 	minetest.register_node(def.nodename_prefix.."_st_45", advtrains.merge_tables(common_def, make_overdef("st_45", 1, 5), def.straight45 or {}))

trainlogic.lua

@@ -18,6 +18,7 @@ end
 
 
 advtrains.trains={}
+advtrains.wagon_save={}
 
 --load initially
 advtrains.fpath=minetest.get_worldpath().."/advtrains"
@@ -169,7 +170,7 @@ function advtrains.train_step(id, train, dtime)
 	end
 	
 	--check for any trainpart entities if they have been unloaded. do this only if both front and end positions are loaded, to ensure train entities will be placed inside loaded area, and only every second.
-	train.check_trainpartload=train.check_trainpartload-dtime
+	train.check_trainpartload=(train.check_trainpartload or 0)-dtime
 	if train.check_trainpartload<=0 and posfront and posback and minetest.get_node_or_nil(posfront) and minetest.get_node_or_nil(posback) then
 		--it is better to iterate luaentites only once
 		local found_uids={}
@@ -177,7 +178,7 @@ function advtrains.train_step(id, train, dtime)
 			if wagon.is_wagon and wagon.initialized and wagon.train_id==id then
 				if found_uids[wagon.unique_id] then
 					--duplicate found, delete it
-					wagon.object and wagon.object:remove()
+					if wagon.object then wagon.object:remove() end
 				else
 					found_uids[wagon.unique_id]=true
 				end
@@ -189,13 +190,15 @@ function advtrains.train_step(id, train, dtime)
 				found_uids[w_id]=nil
 			elseif advtrains.wagon_save[w_id] then
 				--spawn a new and initialize it with the properties from wagon_save
-				local le=minetest.env:add_entity(posfront, "advtrains:"..sysname):get_luaentity()
+				local le=minetest.env:add_entity(posfront, advtrains.wagon_save[w_id].name):get_luaentity()
 				for k,v in pairs(advtrains.wagon_save[w_id]) do
 					le[k]=v
 				end
+				advtrains.wagon_save[w_id].name=nil
+				advtrains.wagon_save[w_id].object=nil
 			else
 				--what the hell...
-				local le=minetest.env:add_entity(posfront, "advtrains:"..sysname):get_luaentity()
+				local le=minetest.env:add_entity(posfront, advtrains.wagon_save[w_id].name):get_luaentity()
 				le.unique_id=w_id
 				le.train_id=id
 				le.pos_in_trainparts=pit

wagons.lua

@@ -72,6 +72,13 @@ function wagon:on_activate(staticdata, dtime_s)
 	--does this object already have an ID?
 	if not self.unique_id then
 		self.unique_id=os.time()..os.clock()--should be random enough.
+	else
+		for _,wagon in pairs(minetest.luaentities) do
+			if wagon.is_wagon and wagon.initialized and wagon.unique_id==self.unique_id then--i am a duplicate!
+				self.object:remove()
+				return
+			end
+		end
 	end
 	--is my train still here
 	if not self.train_id or not self:train() then