diff --git a/generate.lua b/generate.lua
index ffbaf66..4050e82 100644
--- a/generate.lua
+++ b/generate.lua
@@ -1,15 +1,16 @@
-local EvolutionModel = dofile(mapgen_rivers.modpath .. '/erosion.lua')
-local twist = dofile(mapgen_rivers.modpath .. '/twist.lua')
+local EvolutionModel = dofile(mapgen_rivers.modpath .. '/terrainlib_lua/erosion.lua')
+local twist = dofile(mapgen_rivers.modpath .. '/terrainlib_lua/twist.lua')
 
 local size = {x=1000, y=1000}
 local blocksize = 12
+local variation_speed = 70
 
 local np_base = {
 	offset = 0,
 	scale = 200,
 	seed = 2469,
 	octaves = 8,
-	spread = {x=4000/blocksize, y=4000/blocksize, z=5},
+	spread = {x=4000/blocksize, y=4000/blocksize, z=4000/blocksize},
 	persist = 0.6,
 	lacunarity = 2,
 }
@@ -20,10 +21,14 @@ local niter = math.ceil(time/time_step)
 time_step = time / niter
 
 local function generate()
-	local nobj_base = minetest.get_perlin_map(np_base, size)
-	nobj_base:calc_3d_map({x=0, y=0, z=0})
+	local seed = tonumber(minetest.get_mapgen_setting("seed"))
+	np_base.seed = (np_base.seed or 0) + seed
 
-	local dem = nobj_base:get_map_slice({z=1}, {z=1})
+	local nobj_base = PerlinNoiseMap(np_base, {x=size.x, y=1, z=size.y})
+	--nobj_base:calc_3d_map({x=0, y=0, z=0})
+
+	--local dem = nobj_base:get_map_slice({z=1}, {z=1})
+	local dem = nobj_base:get_3d_map_flat({x=0, y=0, z=0})
 	dem.X = size.x
 	dem.Y = size.y
 
@@ -31,8 +36,10 @@ local function generate()
 	model.dem = dem
 	local ref_dem = model:define_isostasy(dem)
 
+	local variation_step = variation_speed * time_step
 	for i=1, niter do
-		nobj_base:get_map_slice({z=i+1}, {z=1}, ref_dem)
+		--nobj_base:get_map_slice({z=i+1}, {z=1}, ref_dem)
+		nobj_base:get_3d_map_flat({x=0, y=variation_step*i, z=0}, ref_dem)
 
 		model:diffuse(time_step)
 		model:flow()
@@ -44,9 +51,12 @@ local function generate()
 	local mfloor = math.floor
 	local mmin, mmax = math.min, math.max
 	local offset_x, offset_y = twist(model.dirs, model.rivers, 5)
-	for i=1, X*Y do
+	local dirs = model.dirs
+	local converter = {2, 1, 4, 3, [0]=0}
+	for i=1, size.x*size.y do
 		offset_x[i] = mmin(mmax(offset_x[i]*256, -128), 127)
 		offset_y[i] = mmin(mmax(offset_y[i]*256, -128), 127)
+		dirs[i] = converter[dirs[i]] -- TODO Fix this
 	end
 
 	mapgen_rivers.write_map('dem', model.dem, 2)
@@ -56,7 +66,7 @@ local function generate()
 	mapgen_rivers.write_map('offset_x', offset_x, 1)
 	mapgen_rivers.write_map('offset_y', offset_y, 1)
 	local sfile = io.open(mapgen_rivers.world_data_path .. 'size', "w")
-	sfile:write(X..'\n'..Y)
+	sfile:write(size.x..'\n'..size.y)
 	sfile:close()
 end
 
diff --git a/init.lua b/init.lua
index 9455493..5e0faea 100644
--- a/init.lua
+++ b/init.lua
@@ -2,7 +2,7 @@ mapgen_rivers = {}
 
 local modpath = minetest.get_modpath(minetest.get_current_modname()) .. '/'
 mapgen_rivers.modpath = modpath
-mapgen_rivers.world_data_path = minetest.get_worldpath() .. '/river_data'
+mapgen_rivers.world_data_path = minetest.get_worldpath() .. '/river_data/'
 
 dofile(modpath .. 'settings.lua')
 
diff --git a/load.lua b/load.lua
index 859c45f..740e3f8 100644
--- a/load.lua
+++ b/load.lua
@@ -1,4 +1,4 @@
-local worldpath = minetest.world_data_path
+local worldpath = mapgen_rivers.world_data_path
 
 function mapgen_rivers.load_map(filename, bytes, signed, size)
 	local file = io.open(worldpath .. filename, 'rb')
diff --git a/polygons.lua b/polygons.lua
index 7ef9538..d767b26 100644
--- a/polygons.lua
+++ b/polygons.lua
@@ -4,7 +4,7 @@ if not io.open(mod_data_path .. 'size', 'r') then
 	mod_data_path = modpath .. 'demo_data/'
 end
 
-local world_data_path = minetest.world_data_path
+local world_data_path = mapgen_rivers.world_data_path
 minetest.mkdir(world_data_path)
 
 dofile(modpath .. 'load.lua')
@@ -26,15 +26,15 @@ sfile:close()
 
 local dem = mapgen_rivers.load_map('dem', 2, true, X*Z)
 local lakes = mapgen_rivers.load_map('lakes', 2, true, X*Z)
-local dirs = mapen_rivers.load_map('dirs', 1, false, X*Z)
+local dirs = mapgen_rivers.load_map('dirs', 1, false, X*Z)
 local rivers = mapgen_rivers.load_map('rivers', 4, false, X*Z)
 
-local offset_x = load_map('offset_x', 1, true, X*Z)
+local offset_x = mapgen_rivers.load_map('offset_x', 1, true, X*Z)
 for k, v in ipairs(offset_x) do
 	offset_x[k] = (v+0.5)/256
 end
 
-local offset_z = load_map('offset_y', 1, true, X*Z)
+local offset_z = mapgen_rivers.load_map('offset_y', 1, true, X*Z)
 for k, v in ipairs(offset_z) do
 	offset_z[k] = (v+0.5)/256
 end
diff --git a/terrainlib_lua/erosion.lua b/terrainlib_lua/erosion.lua
index f13d916..4804355 100644
--- a/terrainlib_lua/erosion.lua
+++ b/terrainlib_lua/erosion.lua
@@ -110,7 +110,7 @@ end
 
 local modpath = ""
 if minetest then
-    if minetest.global_exists(mapgen_rivers) then
+    if minetest.global_exists('mapgen_rivers') then
         modpath = mapgen_rivers.modpath .. "terrainlib_lua/"
     else
         modpath = minetest.get_modpath(minetest.get_current_modname()) .. "terrainlib_lua/"
diff --git a/terrainlib_lua/rivermapper.lua b/terrainlib_lua/rivermapper.lua
index ecf0203..66955be 100644
--- a/terrainlib_lua/rivermapper.lua
+++ b/terrainlib_lua/rivermapper.lua
@@ -29,7 +29,7 @@ local flow_methods = {
 
 local function flow_routing(dem, dirs, lakes, method)
 	method = method or 'semirandom'
-	flow_local = flow_methods[method] or flow_local_semirandom
+	local flow_local = flow_methods[method] or flow_local_semirandom
 
 	dirs = dirs or {}
 	lakes = lakes or {}
@@ -194,7 +194,7 @@ local function flow_routing(dem, dirs, lakes, method)
 		end
 	end
 
-	basin_graph = {}
+	local basin_graph = {}
 	for n=1, nbasins do
 		--print(n, nbasins)
 		local b1, lnk1 = next(lowlevel)