Made interactive loading optional but enabled by default

load.lua

@@ -64,6 +64,9 @@ local loader_mt = {
 function mapgen_rivers.interactive_loader(filename, bytes, signed, size, converter)
 	local file = io.open(worldpath .. filename, 'rb')
 	if file then
+		minetest.register_on_shutdown(function()
+			file:close()
+		end)
 		converter = converter or false
 		return setmetatable({file=file, bytes=bytes, signed=signed, size=size, conv=converter}, loader_mt)
 	end

polygons.lua

@@ -18,36 +18,62 @@ local function offset_converter(o)
 	return (o + 0.5) * (1/256)
 end
 
+local load_all = mapgen_rivers.settings.load_all
+
 -- Try to read file 'size'
 local sfile = io.open(world_data_path..'size', 'r')
+local first_mapgen = true
 if sfile then
 	X, Z = tonumber(sfile:read('*l')), tonumber(sfile:read('*l'))
 	sfile:close()
+	first_mapgen = false
+end
 
-	minetest.register_on_mods_loaded(function()
-		local grid = mapgen_rivers.grid
-		grid.dem = mapgen_rivers.interactive_loader('dem', 2, true, X*Z)
-		grid.lakes = mapgen_rivers.interactive_loader('lakes', 2, true, X*Z)
-		grid.dirs = mapgen_rivers.interactive_loader('dirs', 1, false, X*Z)
-		grid.rivers = mapgen_rivers.interactive_loader('rivers', 4, false, X*Z)
-
-		grid.offset_x = mapgen_rivers.interactive_loader('offset_x', 1, true, X*Z, offset_converter)
-		grid.offset_y = mapgen_rivers.interactive_loader('offset_y', 1, true, X*Z, offset_converter)
-	end)
-else
+if first_mapgen then
 	-- Generate a map!!
 	local pregenerate = dofile(mapgen_rivers.modpath .. '/pregenerate.lua')
 	minetest.register_on_mods_loaded(function()
-		pregenerate()
-		local offset_x = mapgen_rivers.grid.offset_x
-		local offset_y = mapgen_rivers.grid.offset_y
-		for i=1, X*Z do
-			offset_x[i] = offset_converter(offset_x[i])
-			offset_y[i] = offset_converter(offset_y[i])
+		print('Generating grid')
+		pregenerate(load_all)
+
+		if load_all then
+			local offset_x = mapgen_rivers.grid.offset_x
+			local offset_y = mapgen_rivers.grid.offset_y
+			for i=1, X*Z do
+				offset_x[i] = offset_converter(offset_x[i])
+				offset_y[i] = offset_converter(offset_y[i])
+			end
 		end
 	end)
 end
 
+-- if data not already loaded
+if not (first_mapgen and load_all) then
+	local load_map
+	if load_all then
+		load_map = mapgen_rivers.load_map
+	else
+		load_map = mapgen_rivers.interactive_loader
+	end
+
+	minetest.register_on_mods_loaded(function()
+		if load_all then
+			print('Loading full grid')
+		else
+			print('Loading grid as interactive loaders')
+		end
+		local grid = mapgen_rivers.grid
+
+		grid.dem = load_map('dem', 2, true, X*Z)
+		grid.lakes = load_map('lakes', 2, true, X*Z)
+		grid.dirs = load_map('dirs', 1, false, X*Z)
+		grid.rivers = load_map('rivers', 4, false, X*Z)
+
+		grid.offset_x = load_map('offset_x', 1, true, X*Z, offset_converter)
+		grid.offset_y = load_map('offset_y', 1, true, X*Z, offset_converter)
+	end)
+end
+
 mapgen_rivers.grid.size = {x=X, y=Z}
 
 local function index(x, z)

pregenerate.lua

@@ -13,7 +13,7 @@ local time_step = mapgen_rivers.settings.evol_time_step
 local niter = math.ceil(time/time_step)
 time_step = time / niter
 
-local function pregenerate()
+local function pregenerate(keep_loaded)
 	local grid = mapgen_rivers.grid
 	local size = grid.size
 
@@ -66,12 +66,14 @@ local function pregenerate()
 	sfile:write(size.x..'\n'..size.y)
 	sfile:close()
 
-    grid.dem = model.dem
-    grid.lakes = model.lakes
-    grid.dirs = model.dirs
-    grid.rivers = model.rivers
-    grid.offset_x = offset_x
-    grid.offset_y = offset_y
+	if keep_loaded then
+	    grid.dem = model.dem
+	    grid.lakes = model.lakes
+	    grid.dirs = model.dirs
+	    grid.rivers = model.rivers
+	    grid.offset_x = offset_x
+	    grid.offset_y = offset_y
+	end
 end
 
 return pregenerate

settings.lua

@@ -61,6 +61,8 @@ mapgen_rivers.settings = {
 	tectonic_speed = def_setting('tectonic_speed', 'number', 70),
 	evol_time = def_setting('evol_time', 'number', 10),
 	evol_time_step = def_setting('evol_time_step', 'number', 1),
+
+    load_all = mtsettings:get_bool('mapgen_rivers_load_all')
 }
 
 local function write_settings()

settingtypes.txt

@@ -46,6 +46,11 @@ mapgen_rivers_glacier_widening_factor (Glacier widening factor) float 8.0 1.0 20
 #    This results in mountains being more covered by snow.
 mapgen_rivers_elevation_chill (Elevation chill) float 0.25 0.0 5.0
 
+#    If enabled, loads all grid data in memory at init time.
+#    If disabled, data will be loaded on request and cached in memory.
+#    It's recommended to disable it for very large maps (> 2000 grid nodes or so)
+mapgen_rivers_load_all (Load all data in memory) bool false
+
 [Landscape evolution parameters]
 
 #    Modelled landscape evolution time, in arbitrary units