Express map size in Minetest nodes, not in river grid nodes

This introduces new parameters 'map_x_size' and 'map_z_size' that default to 15K
Deprecates 'grid_x_size' and 'grid_z_size'; if they are present, corresponding
values of 'map_x_size' and 'map_z_size' are automatically written in config files.
Also rework compatibility system to better compare versions,
and bump version to 1.0.2-dev1.

compatibility.lua

@@ -1,3 +1,21 @@
+local function version_is_lower(v1, v2)
+	local d1, c1, d2, c2
+	while #v1 > 0 and #v2 > 0 do
+		d1, c1, v1 = v1:match("^(%d*)(%D*)(.*)$")
+		d2, c2, v2 = v2:match("^(%d*)(%D*)(.*)$")
+
+		d1 = tonumber(d1) or -1
+		d2 = tonumber(d2) or -1
+		if d1 ~= d2 then
+			return d1 < d2
+		end
+		if c1 ~= c2 then
+			return c1 < c2
+		end
+	end
+	return false
+end
+
 local function fix_min_catchment(settings, is_global)
 	local prefix = is_global and "mapgen_rivers_" or ""
 
@@ -21,6 +39,18 @@ local function fix_compatibility_minetest(settings)
 	if previous_version == "0.0" then
 		fix_min_catchment(settings, true)
 	end
+
+	if version_is_lower(previous_version, "1.0.2-dev1") then
+		local blocksize = tonumber(settings:get("mapgen_rivers_blocksize") or 15)
+		local grid_x_size = tonumber(settings:get("mapgen_rivers_grid_x_size"))
+		if grid_x_size then
+			settings:set("mapgen_rivers_map_x_size", tostring(grid_x_size * blocksize))
+		end
+		local grid_z_size = tonumber(settings:get("mapgen_rivers_grid_z_size"))
+		if grid_z_size then
+			settings:set("mapgen_rivers_map_z_size", tostring(grid_z_size * blocksize))
+		end
+	end
 end
 
 local function fix_compatibility_mapgen_rivers(settings)
@@ -29,6 +59,18 @@ local function fix_compatibility_mapgen_rivers(settings)
 	if previous_version == "0.0" then
 		fix_min_catchment(settings, false)
 	end
+
+	if version_is_lower(previous_version, "1.0.2-dev1") then
+		local blocksize = tonumber(settings:get("blocksize") or 15)
+		local grid_x_size = tonumber(settings:get("grid_x_size"))
+		if grid_x_size then
+			settings:set("map_x_size", tostring(grid_x_size * blocksize))
+		end
+		local grid_z_size = tonumber(settings:get("grid_z_size"))
+		if grid_z_size then
+			settings:set("map_z_size", tostring(grid_z_size * blocksize))
+		end
+	end
 end
 
 return fix_compatibility_minetest, fix_compatibility_mapgen_rivers

heightmap.lua

@@ -46,57 +46,50 @@ local function heightmaps(minp, maxp)
 				-- = 0: on riverbank
 				-- > 0: inside river
 				local depth_factors = {
-					r_west  -    xf , -- West edge (1)
-					r_north -    zf , -- North edge (2)
-					r_east  - (1-xf), -- East edge (3)
-					r_south - (1-zf), -- South edge (4)
-					c_NW -    xf  -    zf , -- North-West corner (5)
-					c_NE - (1-xf) -    zf , -- North-East corner (6)
-					c_SE - (1-xf) - (1-zf), -- South-East corner (7)
-					c_SW -    xf  - (1-zf), -- South-West corner (8)
+					r_west - xf,
+					r_north - zf,
+					xf - r_east,
+					zf - r_south,
+					c_NW-xf-zf,
+					xf-zf-c_NE,
+					xf+zf-c_SE,
+					zf-xf-c_SW,
 				}
 
-				-- Find the maximal depth factor, which determines to which of the 8 river sections (4 edges + 4 corners) the current point belongs.
-				-- If imax is still at 0, it means that we are not in a river.
-				local dpmax = 0
+				-- Find the maximal depth factor and determine to which river it belongs
+				local depth_factor_max = 0
 				local imax = 0
 				for i=1, 8 do
-					if depth_factors[i] > dpmax then
-						dpmax = depth_factors[i]
+					if depth_factors[i] >= depth_factor_max then
+						depth_factor_max = depth_factors[i]
 						imax = i
 					end
 				end
 
-				-- Transform the coordinates to have xfc and zfc = 0 or 1 in rivers (to avoid rivers having lateral slope and to accomodate the riverbanks smoothly)
-				local xfc, zfc
-				-- xfc:
-				if imax == 0 or imax == 2 or imax == 4 then -- river segment does not constrain X coordinate, so accomodate xf in function of other river sections
-					local x0 =   max(r_west-dpmax, c_NW-zf-dpmax, c_SW-(1-zf)-dpmax, 0) -- new xf will be bounded to 0 by western riverbank
-					local x1 = 1-max(r_east-dpmax, c_NE-zf-dpmax, c_SE-(1-zf)-dpmax, 0) -- and bounded to 1 by eastern riverbank
-					if x0 >= x1 then
-						xfc = 0.5
-					else
-						xfc = (xf-x0) / (x1-x0)
-					end
-				elseif imax == 1 or imax == 5 or imax == 8 then -- river at the western side of the polygon
-					xfc = 0
-				else -- 3, 6, 7 : river at the eastern side of the polygon
-					xfc = 1
-				end
-
-				-- Same for zfc:
-				if imax == 0 or imax == 1 or imax == 3 then -- river segment does not constrain Z coordinate, so accomodate zf in function of other river sections
-					local z0 =   max(r_north-dpmax, c_NW-xf-dpmax, c_NE-(1-xf)-dpmax, 0) -- new zf will be bounded to 0 by northern riverbank
-					local z1 = 1-max(r_south-dpmax, c_SW-xf-dpmax, c_SE-(1-xf)-dpmax, 0) -- and bounded to 1 by southern riverbank
-					if z0 >= z1 then
-						zfc = 0.5
-					else
-						zfc = (zf-z0) / (z1-z0)
-					end
-				elseif imax == 2 or imax == 5 or imax == 6 then -- river at the northern side of the polygon
-					zfc = 0
-				else -- 4, 7, 8 : river at the southern side of the polygon
-					zfc = 1
+				-- Transform the coordinates to have xf and zf = 0 or 1 in rivers (to avoid rivers having lateral slope and to accomodate the surrounding smoothly)
+				if imax == 0 then
+					local x0 = max(r_west, c_NW-zf, zf-c_SW)
+					local x1 = min(r_east, c_NE+zf, c_SE-zf)
+					local z0 = max(r_north, c_NW-xf, xf-c_NE)
+					local z1 = min(r_south, c_SW+xf, c_SE-xf)
+					xf = (xf-x0) / (x1-x0)
+					zf = (zf-z0) / (z1-z0)
+				elseif imax == 1 then
+					xf = 0
+				elseif imax == 2 then
+					zf = 0
+				elseif imax == 3 then
+					xf = 1
+				elseif imax == 4 then
+					zf = 1
+				elseif imax == 5 then
+					xf, zf = 0, 0
+				elseif imax == 6 then
+					xf, zf = 1, 0
+				elseif imax == 7 then
+					xf, zf = 1, 1
+				elseif imax == 8 then
+					xf, zf = 0, 1
 				end
 
 				-- Determine elevation by interpolation
@@ -106,12 +99,12 @@ local function heightmaps(minp, maxp)
 					vdem[2],
 					vdem[3],
 					vdem[4],
-					xfc, zfc
+					xf, zf
 				))
 
 				-- Spatial gradient of the interpolation
-				local slope_x = zfc*(vdem[3]-vdem[4]) + (1-zfc)*(vdem[2]-vdem[1]) < 0
-				local slope_z = xfc*(vdem[3]-vdem[2]) + (1-xfc)*(vdem[4]-vdem[1]) < 0
+				local slope_x = zf*(vdem[3]-vdem[4]) + (1-zf)*(vdem[2]-vdem[1]) < 0
+				local slope_z = xf*(vdem[3]-vdem[2]) + (1-xf)*(vdem[4]-vdem[1]) < 0
 				local lake_id = 0
 				if slope_x then
 					if slope_z then
@@ -128,8 +121,8 @@ local function heightmaps(minp, maxp)
 				end
 				local lake_height = max(floor(poly.lake[lake_id]), terrain_height)
 
-				if imax > 0 and dpmax > 0 then
-					terrain_height = min(max(lake_height, sea_level) - floor(1+dpmax*riverbed_slope), terrain_height)
+				if imax > 0 and depth_factor_max > 0 then
+					terrain_height = min(max(lake_height, sea_level) - floor(1+depth_factor_max*riverbed_slope), terrain_height)
 				end
 
 				terrain_height_map[i] = terrain_height

init.lua

@@ -21,7 +21,6 @@ use_biomes = use_biomes and minetest.global_exists('default') and not use_biomeg
 if use_biomegen_mod then
 	biomegen.set_elevation_chill(elevation_chill)
 end
-dofile(modpath .. 'noises.lua')
 
 local heightmaps = dofile(modpath .. 'heightmap.lua')
 

noises.lua

@@ -1,80 +0,0 @@
-local def_setting = mapgen_rivers.define_setting
-
-mapgen_rivers.noise_params = {
-	base = def_setting('np_base', 'noise', {
-		offset = 0,
-		scale = 300,
-		seed = 2469,
-		octaves = 8,
-		spread = {x=2048, y=2048, z=2048},
-		persist = 0.6,
-		lacunarity = 2,
-		flags = "eased",
-	}),
-
-	distort_x = def_setting('np_distort_x', 'noise', {
-		offset = 0,
-		scale = 1,
-		seed = -4574,
-		spread = {x=64, y=32, z=64},
-		octaves = 3,
-		persistence = 0.75,
-		lacunarity = 2,
-	}),
-
-	distort_z = def_setting('np_distort_z', 'noise', {
-		offset = 0,
-		scale = 1,
-		seed = -7940,
-		spread = {x=64, y=32, z=64},
-		octaves = 3,
-		persistence = 0.75,
-		lacunarity = 2,
-	}),
-
-	distort_amplitude = def_setting('np_distort_amplitude', 'noise', {
-		offset = 0,
-		scale = 10,
-		seed = 676,
-		spread = {x=1024, y=1024, z=1024},
-		octaves = 5,
-		persistence = 0.5,
-		lacunarity = 2,
-		flags = "absvalue",
-	}),
-
-	heat = minetest.get_mapgen_setting_noiseparams('mg_biome_np_heat'),
-	heat_blend = minetest.get_mapgen_setting_noiseparams('mg_biome_np_heat_blend'),
-}
-
--- Convert to number because Minetest API is not able to do it cleanly...
-for name, np in pairs(mapgen_rivers.noise_params) do
-	for field, value in pairs(np) do
-		if field ~= 'flags' and type(value) == 'string' then
-			np[field] = tonumber(value) or value
-		elseif field == 'spread' then
-			for dir, v in pairs(value) do
-				value[dir] = tonumber(v) or v
-			end
-		end
-	end
-end
-
-local heat = mapgen_rivers.noise_params.heat
-local base = mapgen_rivers.noise_params.base
-local settings = mapgen_rivers.settings
-heat.offset = heat.offset + settings.sea_level * settings.elevation_chill
-base.spread.x = base.spread.x / settings.blocksize
-base.spread.y = base.spread.y / settings.blocksize
-base.spread.z = base.spread.z / settings.blocksize
-
-for name, np in pairs(mapgen_rivers.noise_params) do
-	local lac = np.lacunarity or 2
-	if lac > 1 then
-		local omax = math.floor(math.log(math.min(np.spread.x, np.spread.y, np.spread.z)) / math.log(lac))+1
-		if np.octaves > omax then
-			minetest.log("warning", "[mapgen_rivers] Noise " .. name .. ": 'octaves' reduced to " .. omax)
-			np.octaves = omax
-		end
-	end
-end

polygons.lua

@@ -11,8 +11,9 @@ dofile(modpath .. 'load.lua')
 
 mapgen_rivers.grid = {}
 
-local X = mapgen_rivers.settings.grid_x_size
-local Z = mapgen_rivers.settings.grid_z_size
+local blocksize = mapgen_rivers.settings.blocksize
+local X = math.floor(mapgen_rivers.settings.map_x_size / blocksize)
+local Z = math.floor(mapgen_rivers.settings.map_z_size / blocksize)
 
 local function offset_converter(o)
 	return (o + 0.5) * (1/256)
@@ -80,7 +81,6 @@ local function index(x, z)
 	return z*X+x+1
 end
 
-local blocksize = mapgen_rivers.settings.blocksize
 local min_catchment = mapgen_rivers.settings.min_catchment
 local max_catchment = mapgen_rivers.settings.max_catchment
 
@@ -236,15 +236,15 @@ local function make_polygons(minp, maxp)
 				end
 			end
 
-			polygon.river_corners = {riverA, riverB, riverC, riverD}
+			polygon.river_corners = {riverA, 1-riverB, 2-riverC, 1-riverD}
 
 			-- Flow directions
 			local dirA, dirB, dirC, dirD = dirs[iA], dirs[iB], dirs[iC], dirs[iD]
 			-- Determine the river flux on the edges, by testing dirs values
 			local river_west = (dirA==1 and riverA or 0) + (dirD==3 and riverD or 0)
 			local river_north = (dirA==2 and riverA or 0) + (dirB==4 and riverB or 0)
-			local river_east = (dirB==1 and riverB or 0) + (dirC==3 and riverC or 0)
-			local river_south = (dirD==2 and riverD or 0) + (dirC==4 and riverC or 0)
+			local river_east = 1 - (dirB==1 and riverB or 0) - (dirC==3 and riverC or 0)
+			local river_south = 1 - (dirD==2 and riverD or 0) - (dirC==4 and riverC or 0)
 
 			polygon.rivers = {river_west, river_north, river_east, river_south}
 		end

pregenerate.lua

@@ -5,6 +5,7 @@ local blocksize = mapgen_rivers.settings.blocksize
 local tectonic_speed = mapgen_rivers.settings.tectonic_speed
 
 local np_base = table.copy(mapgen_rivers.noise_params.base)
+np_base.spread = vector.divide(np_base.spread, blocksize)
 
 local evol_params = mapgen_rivers.settings.evol_params
 
@@ -17,6 +18,10 @@ local function pregenerate(keep_loaded)
 	local grid = mapgen_rivers.grid
 	local size = grid.size
 
+	if size.x * size.y > 4e6 then
+		minetest.log("warning", "[mapgen_rivers] You are going to generate a very large grid (>4M nodes). If you experience problems, you should increase blocksize or reduce map size.")
+	end
+
 	local seed = tonumber(minetest.get_mapgen_setting("seed"))
 	np_base.seed = (np_base.seed or 0) + seed
 

settings.lua

@@ -1,7 +1,7 @@
 local mtsettings = minetest.settings
 local mgrsettings = Settings(minetest.get_worldpath() .. '/mapgen_rivers.conf')
 
-mapgen_rivers.version = "1.0.2"
+mapgen_rivers.version = "1.0.2-dev1"
 
 local previous_version_mt = mtsettings:get("mapgen_rivers_version") or "0.0"
 local previous_version_mgr = mgrsettings:get("version") or "0.0"
@@ -19,13 +19,33 @@ end
 mtsettings:set("mapgen_rivers_version", mapgen_rivers.version)
 mgrsettings:set("version", mapgen_rivers.version)
 
+local defaults
+do
+	local f = io.open(mapgen_rivers.modpath .. "/settings_default.json")
+	defaults = minetest.parse_json(f:read("*all"))
+	f:close()
+end
+
+-- Convert strings to numbers in noise params because Minetest API is not able to do it cleanly...
+local function clean_np(np)
+	for field, value in pairs(np) do
+		if field ~= 'flags' and type(value) == 'string' then
+			np[field] = tonumber(value) or value
+		elseif field == 'spread' then
+			for dir, v in pairs(value) do
+				value[dir] = tonumber(v) or v
+			end
+		end
+	end
+end
+
 function mapgen_rivers.define_setting(name, dtype, default)
 	if dtype == "number" or dtype == "string" then
 		local v = mgrsettings:get(name)
 		if v == nil then
 			v = mtsettings:get('mapgen_rivers_' .. name)
 			if v == nil then
-				v = default
+				v = defaults[name]
 			end
 			mgrsettings:set(name, v)
 		end
@@ -39,7 +59,7 @@ function mapgen_rivers.define_setting(name, dtype, default)
 		if v == nil then
 			v = mtsettings:get_bool('mapgen_rivers_' .. name)
 			if v == nil then
-				v = default
+				v = defaults[name]
 			end
 			mgrsettings:set_bool(name, v)
 		end
@@ -49,10 +69,11 @@ function mapgen_rivers.define_setting(name, dtype, default)
 		if v == nil then
 			v = mtsettings:get_np_group('mapgen_rivers_' .. name)
 			if v == nil then
-				v = default
+				v = defaults[name]
 			end
 			mgrsettings:set_np_group(name, v)
 		end
+		clean_np(v)
 		return v
 	end
 end
@@ -60,33 +81,46 @@ end
 local def_setting = mapgen_rivers.define_setting
 
 mapgen_rivers.settings = {
-	center = def_setting('center', 'bool', true),
-	blocksize = def_setting('blocksize', 'number', 15),
+	center = def_setting('center', 'bool'),
+	blocksize = def_setting('blocksize', 'number'),
 	sea_level = tonumber(minetest.get_mapgen_setting('water_level')),
-	min_catchment = def_setting('min_catchment', 'number', 3600),
-	river_widening_power = def_setting('river_widening_power', 'number', 0.5),
-	riverbed_slope = def_setting('riverbed_slope', 'number', 0.4),
-	distort = def_setting('distort', 'bool', true),
-	biomes = def_setting('biomes', 'bool', true),
-	glaciers = def_setting('glaciers', 'bool', false),
-	glacier_factor = def_setting('glacier_factor', 'number', 8),
-	elevation_chill = def_setting('elevation_chill', 'number', 0.25),
+	min_catchment = def_setting('min_catchment', 'number'),
+	river_widening_power = def_setting('river_widening_power', 'number'),
+	riverbed_slope = def_setting('riverbed_slope', 'number'),
+	distort = def_setting('distort', 'bool'),
+	biomes = def_setting('biomes', 'bool'),
+	glaciers = def_setting('glaciers', 'bool'),
+	glacier_factor = def_setting('glacier_factor', 'number'),
+	elevation_chill = def_setting('elevation_chill', 'number'),
 
-	grid_x_size = def_setting('grid_x_size', 'number', 1000),
-	grid_z_size = def_setting('grid_z_size', 'number', 1000),
+	map_x_size = def_setting('map_x_size', 'number'),
+	map_z_size = def_setting('map_z_size', 'number'),
 	evol_params = {
-		K = def_setting('river_erosion_coef', 'number', 0.5),
-		m = def_setting('river_erosion_power', 'number', 0.4),
-		d = def_setting('diffusive_erosion', 'number', 0.5),
-		compensation_radius = def_setting('compensation_radius', 'number', 50),
+		K = def_setting('river_erosion_coef', 'number'),
+		m = def_setting('river_erosion_power', 'number'),
+		d = def_setting('diffusive_erosion', 'number'),
+		compensation_radius = def_setting('compensation_radius', 'number'),
 	},
-	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),
+	tectonic_speed = def_setting('tectonic_speed', 'number'),
+	evol_time = def_setting('evol_time', 'number'),
+	evol_time_step = def_setting('evol_time_step', 'number'),
 
 	load_all = mtsettings:get_bool('mapgen_rivers_load_all')
 }
 
+mapgen_rivers.noise_params = {
+	base = def_setting("np_base", "noise"),
+	distort_x = def_setting("np_distort_x", "noise"),
+	distort_z = def_setting("np_distort_z", "noise"),
+	distort_amplitude = def_setting("np_distort_amplitude", "noise"),
+
+	heat = minetest.get_mapgen_setting_noiseparams('mg_biome_np_heat'),
+	heat_blend = minetest.get_mapgen_setting_noiseparams('mg_biome_np_heat_blend'),
+}
+
+mapgen_rivers.noise_params.heat.offset = mapgen_rivers.noise_params.heat.offset +
+		mapgen_rivers.settings.sea_level * mapgen_rivers.settings.elevation_chill
+
 local function write_settings()
 	mgrsettings:write()
 end

settings_default.json

@@ -0,0 +1,68 @@
+{
+	"version": "1.0.2",
+
+	"center": true,
+	"water_level": 1,
+	"blocksize": 15,
+	"min_catchment": 3600,
+	"river_widening_power": 0.5,
+	"riverbed_slope": 0.4,
+	"distort": true,
+	"biomes": true,
+	"glaciers": false,
+	"glacier_factor": 8,
+	"elevation_chill": 0.25,
+
+	"map_x_size": 15000,
+	"map_z_size": 15000,
+	"river_erosion_coef": 0.5,
+	"river_erosion_power": 0.4,
+	"diffusive_erosion": 0.5,
+	"compensation_radius": 50,
+	"tectonic_speed": 70,
+	"evol_time": 10,
+	"evol_time_step": 1,
+	"load_all": false,
+
+	"np_base": {
+		"offset": 0,
+		"scale": 300,
+		"seed": 2469,
+		"octaves": 8,
+		"spread": {"x": 2048, "y": 2048, "z": 2048},
+		"persist": 0.6,
+		"lacunarity": 2.0,
+		"flags": "eased"
+	},
+
+	"np_distort_x": {
+		"offset": 0,
+		"scale": 1,
+		"seed": -4574,
+		"octaves": 3,
+		"spread": {"x": 64, "y": 32, "z": 64},
+		"persist": 0.75,
+		"lacunarity": 2.0
+	},
+
+	"np_distort_z": {
+		"offset": 0,
+		"scale": 1,
+		"seed": -7940,
+		"octaves": 3,
+		"spread": {"x": 64, "y": 32, "z": 64},
+		"persist": 0.75,
+		"lacunarity": 2.0
+	},
+
+	"np_distort_amplitude": {
+		"offset": 0,
+		"scale": 10,
+		"seed": 676,
+		"octaves": 5,
+		"spread": {"x": 1024, "y": 1024, "z": 1024},
+		"persist": 0.5,
+		"lacunarity": 2.0,
+		"flags": "absvalue"
+	}
+}

settingtypes.txt

@@ -3,19 +3,25 @@
 #    Whether the map should be centered at x=0, z=0.
 mapgen_rivers_center (Center map) bool true
 
-#    Represents horizontal map scale. Every cell of the grid will be upscaled to
-#    a square of this size.
-#    For example if the grid size is 1000x1000 and block size is 12,
-#    the actual size of the map will be 12000.
+#    Every cell of the river grid will represent a square of this size.
+#    A lower value will result in more detailed terrain and finer computation
+#    of rivers, but will be slower to generate and use more resources.
+#
+#    WARNING: Excessively low values may cause crashes at pre-generation, due to
+#    memory issues
 mapgen_rivers_blocksize (Block size) float 15.0 2.0 100.0
 
-#    X size of the grid being generated
-#    Actual size of the map is grid_x_size * blocksize
-mapgen_rivers_grid_x_size (Grid X size) int 1000 50 5000
+#    X size of the map being generated
+#
+#    X size of the river grid will be this/blocksize
+#    When increasing, it is recommended to increase blocksize too
+mapgen_rivers_map_x_size (Map X size) int 15000 500 66000
 
-#    Z size of the grid being generated
-#    Actual size of the map is grid_z_size * blocksize
-mapgen_rivers_grid_z_size (Grid Z size) int 1000 50 5000
+#    Z size of the map being generated
+#
+#    Z size of the river grid will be this/blocksize
+#    When increasing, it is recommended to increase blocksize too
+mapgen_rivers_map_z_size (Map Z size) int 15000 500 66000
 
 #    Minimal catchment area for a river to be drawn, in square nodes
 #    Lower value means bigger river density