aboutsummaryrefslogtreecommitdiff
path: root/pseudoload.lua
blob: 47318aed7c96348698cd3828a1ff01b8a299ef07 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147

--pseudoload.lua
--responsible for keeping up a database of all rail nodes existant in the world, regardless of whether the mapchunk is loaded.

advtrains.trackdb={}
--trackdb[tt][y][x][z]={conn1, conn2, rely1, rely2, railheight}
--serialization format:
--(2byte x)(2byte y)(2byte z)(4bits conn1, 4bits conn2)[(plain rely1)|(plain rely2)|(plain railheight)]\n
--[] 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]={}
	local file, err = io.open(pl_fpath, "r")
	if not file then
		local er=err or "Unknown Error"
		print("[advtrains]Failed loading advtrains trackdb save file "..er)
	else
		--custom format to save memory
		while true do
			local xbytes=file:read(2)
			if not xbytes then
				break --eof reached
			end
			local ybytes=file:read(2)
			local zbytes=file:read(2)
			local x=(string.byte(xbytes[1])-128)*256+(string.byte(xbytes[2]))
			local y=(string.byte(ybytes[1])-128)*256+(string.byte(ybytes[2]))
			local z=(string.byte(zbytes[1])-128)*256+(string.byte(zbytes[2]))
			
			local conn1=string.byte(file:read(1))
			local conn1=string.byte(file:read(1))
			
			if not advtrains.trackdb[tt][y] then advtrains.trackdb[tt][y]={} end
			if not advtrains.trackdb[tt][y][x] then advtrains.trackdb[tt][y][x]={} end
			
			local rest=file.read("*l")
			if rest~="" then
				local rely1, rely2, railheight=string.match(rest, "([^|]+)|([^|]+)|([^|]+)")
				if rely1 and rely2 and railheight then
					advtrains.trackdb[tt][y][x][z]={
						conn1=conn1, conn2=conn2,
						rely1=rely1, rely2=rely2,
						railheight=railheight
					}
				else
					advtrains.trackdb[tt][y][x][z]={
						conn1=conn1, conn2=conn2
					}
				end
			else
				advtrains.trackdb[tt][y][x][z]={
					conn1=conn1, conn2=conn2
				}
			end
		end
		file:close()
	end
end

--end minetest.after
end)

function advtrains.save_trackdb()
	for tt, _ in pairs(advtrains.all_traintypes) do
		local pl_fpath=minetest.get_worldpath().."/advtrains_trackdb_"..tt
		local file, err = io.open(pl_fpath, "w")
		if not file then
			local er=err or "Unknown Error"
			print("[advtrains]Failed saving advtrains trackdb save file "..er)
		else
			--custom format to save memory
			for x,txl in pairs(advtrains.trackdb[tt]) do
				for y,tyl in pairs(txl) do
					for z,rail in pairs(tyl) do
						file:write(string.char(math.floor(x/256)+128)..string.char((x%256)))
						file:write(string.char(math.floor(y/256)+128)..string.char((y%256)))
						file:write(string.char(math.floor(z/256)+128)..string.char((z%256)))
						file:write(string.char(rail.conn1))
						file:write(string.char(rail.conn2))
						if (rail.rely1 and rail.rely1~=0) or (rail.rely2 and rail.rely2~=0) or (rail.railheight and rail.railheight~=0) then
							file:write(rail.rely1.."|"..rail.rely2.."|"..rail.railheight)
						end
						file:write("\n")
					end
				end
			end
			file:close()
		end
	end
end

--get_node with pseudoload.
--returns:
--true, conn1, conn2, rely1, rely2, railheight   in case everything's right.
--false  if it's not a rail or the train does not drive on this rail, but it is loaded or
--nil    if the node is neither loaded nor in trackdb
--the distraction between false and nil will be needed only in special cases.(train initpos)
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(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
			return nil
		end
	end
	local nodename=node.name
	if(not advtrains.is_track_and_drives_on(nodename, advtrains.all_traintypes[traintype].drives_on)) then
		return false
	end
	local conn1, conn2, rely1, rely2, railheight=advtrains.get_track_connections(node.name, node.param2)
	
	--already in trackdb?
	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
		}
	end
	
	return true, conn1, conn2, rely1, rely2, railheight
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
end