Add meru mod, disabled so far

mods/meru/README.txt

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+meru 0.3.1 by paramat
+For Minetest 0.4.12 and later
+Depends default
+License WTFPL
+
+Meru mod is a vertical 1 dimensional realm, 1D referring to large scale structure, and can act as a vertical connector between horizontal realms, such as the ground and the floatlands.
+A single spike shaped mountain is created in newly generated chunks, at a random location within a chosen area, by default this area is +/-1024 for use in a new world, to add a mountain to an existing world you need to edit these area parameters to a completely ungenerated part of your world.
+For testing this mod or for cheating edit parameter COORD = true, the co-ordinates of the mountain will be printed to terminal while within the generation area.
+The mountain is a hollow cone made of stone and desert stone, with a smooth transition across biome boundaries. By default the height is 2km. There are a few cave entrances on the surface, these 'fissure system' caves expand under the surface helping the creation of a path upwards. If the mountain generates over water you can use the central conical void to jump down the last few hundred metres.
+There are many parameters for fine tuning the structure, some parameters change smoothly with height or distance from the center. Reducing noise to zero at the center creates a perfect spike as a summit. Constant noise throughout often creates floating islands at the summit. Choosing zero noise throughout creates a smooth geometric conical shape. There is a parameter CONVEX to control whether the basic conical structure bulges outwards or is pinched inwards in the middle.

mods/meru/depends.txt

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+default

mods/meru/init.lua

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+-- Parameters
+
+local COORD = false -- Print tower co-ordinates to terminal (cheat)
+
+local XMIN = 0 -- Area for random spawn
+local XMAX = 0
+local ZMIN = 0
+local ZMAX = 0
+
+local BASRAD = 64 -- Average radius at y = -32
+local HEIGHT = 2048 -- Approximate height measured from y = -32
+local CONVEX = 0.6 -- Convexity. <1 = concave, 1 = conical, >1 = convex
+local VOID = 0.4 -- Void threshold. Controls size of central void
+local NOISYRAD = 0.2 -- Noisyness of structure at base radius.
+						-- 0 = smooth geometric form, 0.3 = noisy.
+local NOISYCEN = 0 -- Noisyness of structure at centre
+local FISOFFBAS = 0.02 -- Fissure noise offset at base,
+						-- controls size of fissure entrances on outer surface.
+local FISOFFTOP = 0.04 -- Fissure noise offset at top
+local FISEXPBAS = 0.6 -- Fissure expansion rate under surface at base
+local FISEXPTOP = 1.2 -- Fissure expansion rate under surface at top
+
+-- 3D noise for primary structure
+
+local np_structure = {
+	offset = 0,
+	scale = 1,
+	spread = {x = 64, y = 64, z = 64},
+	seed = 46893,
+	octaves = 5,
+	persist = 0.5
+}
+
+-- 3D noise for fissures
+
+local np_fissure = {
+	offset = 0,
+	scale = 1,
+	spread = {x = 24, y = 24, z = 24},
+	seed = 92940980987,
+	octaves = 4,
+	persist = 0.5
+}
+
+-- 2D noise for biome. Parameters must match mgv6 biome noise
+
+local np_biome = {
+	offset = 0,
+	scale = 1,
+	spread = {x = 250, y = 250, z = 250},
+	seed = 9130,
+	octaves = 3,
+	persist = 0.5
+}
+
+-- Stuff
+
+local cxmin = math.floor((XMIN + 32) / 80) -- limits in chunk co-ordinates
+local czmin = math.floor((ZMIN + 32) / 80)
+local cxmax = math.floor((XMAX + 32) / 80)
+local czmax = math.floor((ZMAX + 32) / 80)
+local cxav = (cxmin + cxmax) / 2 -- spawn area midpoint in chunk co-ordinates
+local czav = (czmin + czmax) / 2
+local xnom = (cxmax - cxmin) / 4 -- noise multipliers
+local znom = (czmax - czmin) / 4
+
+-- Nodes
+
+minetest.register_node("meru:stone", {
+	description = "Stone",
+	tiles = {"default_stone.png"},
+	is_ground_content = false,
+	groups = {cracky = 3, stone = 1},
+	drop = "default:cobble",
+	sounds = default.node_sound_stone_defaults(),
+})
+
+minetest.register_node("meru:destone", {
+	description = "Desert Stone",
+	tiles = {"default_desert_stone.png"},
+	is_ground_content = false,
+	groups = {cracky = 3, stone = 1},
+	drop = "default:desert_stone",
+	sounds = default.node_sound_stone_defaults(),
+})
+
+-- Initialize noise objects to nil
+
+local nobj_structure = nil
+local nobj_fissure = nil
+local nobj_biome = nil
+
+-- On generated function
+
+minetest.register_on_generated(function(minp, maxp, seed)
+	if maxp.x < XMIN or minp.x > XMAX
+	or maxp.z < ZMIN or minp.z > ZMAX then
+		return
+	end
+
+	local locnoise = minetest.get_perlin(5839090, 2, 0.5, 3)
+	local noisex = locnoise:get2d({x = 31, y = 23})
+	local noisez = locnoise:get2d({x = 17, y = 11})
+	local cx = cxav + math.floor(noisex * xnom) -- chunk co ordinates
+	local cz = czav + math.floor(noisez * znom)
+	local merux = 80 * cx + 8
+	local meruz = 80 * cz + 8
+	if COORD then
+		print ("[meru] at x " .. merux .. " z " .. meruz)
+	end
+	if minp.x < merux - 120 or minp.x > merux + 40
+	or minp.z < meruz - 120 or minp.z > meruz + 40
+	or minp.y < -32 or minp.y > HEIGHT * 1.2 then
+		return
+	end
+
+	local t0 = os.clock()
+	local x0 = minp.x
+	local y0 = minp.y
+	local z0 = minp.z
+	local x1 = maxp.x
+	local y1 = maxp.y
+	local z1 = maxp.z
+	
+	local vm, emin, emax = minetest.get_mapgen_object("voxelmanip")
+	local area = VoxelArea:new{MinEdge = emin, MaxEdge = emax}
+	local data = vm:get_data()
+
+	local c_stone = minetest.get_content_id("default:stone")
+	local c_destone = minetest.get_content_id("default:desert_stone")
+
+	local sidelen = x1 - x0 + 1
+	local chulens3d = {x = sidelen, y = sidelen, z = sidelen}
+	local chulens2d = {x = sidelen, y = sidelen, z = 1}
+	local minpos3d = {x = x0, y = y0, z = z0}
+
+	nobj_structure = nobj_structure or minetest.get_perlin_map(np_structure, chulens3d)
+	nobj_fissure = nobj_fissure or minetest.get_perlin_map(np_fissure, chulens3d)
+	nobj_biome = nobj_biome or minetest.get_perlin_map(np_biome, chulens2d)
+
+	local nvals_structure = nobj_structure:get3dMap_flat(minpos3d)
+	local nvals_fissure = nobj_fissure:get3dMap_flat(minpos3d)
+	local nvals_biome = nobj_biome:get2dMap_flat({x = x0 + 150, y = z0 + 50})
+
+	local nixyz = 1 -- 3D noise index
+	local nixz = 1 -- 2D noise index
+	for z = z0, z1 do
+		for y = y0, y1 do
+			local vi = area:index(x0, y, z)
+			for x = x0, x1 do
+				local n_structure = nvals_structure[nixyz]
+				local radius = ((x - merux) ^ 2 + (z - meruz) ^ 2) ^ 0.5
+				local deprop = (BASRAD - radius) / BASRAD -- radial depth proportion
+				local noisy = NOISYRAD + deprop * (NOISYCEN - NOISYRAD)
+				local heprop = ((y + 32) / HEIGHT) -- height proportion
+				local offset = deprop - heprop ^ CONVEX
+				local n_offstructure = n_structure * noisy + offset
+				if n_offstructure > 0 and n_offstructure < VOID then
+					local n_absfissure = math.abs(nvals_fissure[nixyz])
+					local fisoff = FISOFFBAS + heprop * (FISOFFTOP - FISOFFBAS)
+					local fisexp = FISEXPBAS + heprop * (FISEXPTOP - FISEXPBAS)
+					if n_absfissure - n_offstructure * fisexp - fisoff > 0 then
+						local n_biome = nvals_biome[nixz]
+						local desert = n_biome > 0.45
+						or math.random(0,10) > (0.45 - n_biome) * 100
+						if desert then
+							data[vi] = c_destone
+						else
+							data[vi] = c_stone
+						end
+					end
+				end
+
+				nixyz = nixyz + 1
+				nixz = nixz + 1
+				vi = vi + 1
+			end
+			nixz = nixz - sidelen
+		end
+		nixz = nixz + sidelen
+	end
+
+	vm:set_data(data)
+	vm:set_lighting({day = 0, night = 0})
+	vm:calc_lighting()
+	vm:write_to_map(data)
+
+	local chugent = math.ceil((os.clock() - t0) * 1000)
+	print ("[meru] " .. chugent .. " ms")
+end)

mods/meru/license.txt

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+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+                    Version 2, December 2004
+
+ Copyright (C) 2004 Sam Hocevar <sam@hocevar.net>
+
+ Everyone is permitted to copy and distribute verbatim or modified
+ copies of this license document, and changing it is allowed as long
+ as the name is changed.
+
+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. You just DO WHAT THE FUCK YOU WANT TO.
+                       

worlds/minetestforfun/world.mt

@@ -26,6 +26,7 @@ load_mod_worldedge = true
 load_mod_maze = true
 load_mod_peace_areas = true
 
+load_mod_meru = true
 load_mod_watershed = true
 load_mod_bushes_classic = true
 load_mod_flowers_plus = true