Initial Commit

This ain't no Cave Story.

depends.txt

@@ -0,0 +1 @@
+default

init.lua

@@ -0,0 +1,297 @@
+-- caverealms 0.1.0 by HeroOfTheWinds
+-- For latest stable Minetest and back to 0.4.8
+-- Depends default
+-- License: code WTFPL
+
+-- Parameters
+
+local YMIN = -33000 -- Approximate realm limits.
+local YMAX = -700
+local XMIN = -33000
+local XMAX = 33000
+local ZMIN = -33000
+local ZMAX = 33000
+
+local CHUINT = 2 -- Chunk interval for cave realms
+local WAVAMP = 16 -- Structure wave amplitude
+local HISCAL = 32 -- Upper structure vertical scale
+local LOSCAL = 32 -- Lower structure vertical scale
+local HIEXP = 0.5 -- Upper structure density gradient exponent
+local LOEXP = 0.5 -- Lower structure density gradient exponent
+local DIRTHR = 0.04 -- Dirt density threshold
+local STOTHR = 0.08 -- Stone density threshold
+local STABLE = 2 -- Minimum number of stacked stone nodes in column for dirt / sand on top
+
+local STALAG = 0.02 --chance of stalagmites
+local STALAC = 0.04 --chance of stalactites
+local H_LAG = 15 --max height for stalagmites
+local H_LAC = 20 --...stalactites
+local CRYSTAL = 0.01 --chance of glow crystal formations
+local H_CRY = 6 --max height of glow crystals
+local GEMCHA = 0.03 --chance of small glow gems
+
+
+-- 3D noise for caverns
+
+local np_cave = {
+	offset = 0,
+	scale = 1,
+	spread = {x=512, y=256, z=512},
+	seed = 277777979,
+	octaves = 6,
+	persist = 0.6
+}
+
+-- 3D noise for large scale cavern size/density variation
+
+local np_cluster = {
+	offset = 0,
+	scale = 1,
+	spread = {x=2048, y=2048, z=2048},
+	seed = 23,
+	octaves = 1,
+	persist = 0.5
+}
+
+-- 2D noise for wave
+
+local np_wave = {
+	offset = 0,
+	scale = 1,
+	spread = {x=256, y=256, z=256},
+	seed = -400000000089,
+	octaves = 3,
+	persist = 0.5
+}
+
+-- Stuff
+
+caverealms = {}
+
+-- Nodes
+
+--glowing crystal
+minetest.register_node("caverealms:glow_crystal", {
+	description = "Glow Crystal",
+	tiles = {"caverealms_glow_crystal.png"},
+	is_ground_content = true,
+	groups = {cracky=3},
+	--sounds = "default_break_glass.1.ogg", --broken
+	light_source = 13,
+	paramtype = "light",
+	use_texture_alpha = true,
+	drawtype = "glasslike",
+	sunlight_propagates = true,
+})
+
+--embedded crystal
+minetest.register_node("caverealms:glow_ore", {
+	description = "Glow Crystal Ore",
+	tiles = {"caverealms_glow_ore.png"},
+	is_ground_content = true,
+	groups = {cracky=2},
+	--sounds = "default_break_glass.1.ogg", --broken
+	light_source = 10,
+	paramtype = "light",
+	--use_texture_alpha = true,
+	--drawtype = "allfaces_optional",
+})
+
+--glowing crystal
+minetest.register_node("caverealms:glow_gem", {
+	description = "Glow Gem",
+	tiles = {"caverealms_glow_gem.png"},
+	inventory_image = "caverealms_glow_gem.png",
+	wield_image = "caverealms_glow_gem.png",
+	is_ground_content = true,
+	groups = {cracky=3, oddly_breakable_by_hand=1},
+	--sounds = "default_break_glass.1.ogg", --broken
+	light_source = 11,
+	paramtype = "light",
+	drawtype = "plantlike",
+	walkable = false,
+	buildable_to = true,
+	visual_scale = 1.0,
+	selection_box = {
+		type = "fixed",
+		fixed = {-0.5, -0.5, -0.5, 0.5, -5/16, 0.5},
+	},
+})
+--cave dirt_with_grass - bluish?
+minetest.register_node("caverealms:dirt_with_grass", {
+	description = "Cave Dirt with Grass",
+	tiles = {"caverealms_grass.png", "default_dirt.png", "default_dirt.png^caverealms_grass_side.png"},
+	is_ground_content = true,
+	groups = {crumbly=3,soil=1},
+	drop = 'default:dirt',
+	sounds = default.node_sound_dirt_defaults({
+		footstep = {name="default_grass_footstep", gain=0.25},
+	}),
+})
+--cave plants
+
+--glowing crystal stalagmite spawner
+function caverealms:crystal_stalagmite(x, y, z, area, data)
+	--content IDs
+	local c_crystal = minetest.get_content_id("caverealms:glow_crystal")
+	local c_crystore = minetest.get_content_id("caverealms:glow_ore")
+	
+	for j = 0, H_CRY do --y
+		for k = -2, 2 do --x
+			for l = -2, 2 do --z
+				if j <= math.ceil(H_CRY / 4) then --base
+					if k*k + l*l <= 4 then --make a circle
+						local vi = area:index(x+k, y+j, z+l)
+						if math.random(3) == 1 then
+							data[vi] = c_crystal
+						else
+							data[vi] = c_crystore
+						end
+					end
+				else --top
+					if k >= -1 and k <= 1 then
+					if l >= -1 and l <= 1 then 
+						if j <= H_CRY - 2 then
+							local vi = area:index(x+k, y+j, z+l)
+							if math.random(3) <= 2 then
+								data[vi] = c_crystal
+							else
+								data[vi] = c_crystore
+							end
+						else
+							local vi = area:index(x, y+j, z)
+							data[vi] = c_crystal
+						end
+					end
+					end
+				end
+			end
+		end
+	end
+end
+
+-- On generated function
+
+minetest.register_on_generated(function(minp, maxp, seed)
+	--only continue if within the bounds for creating cave realms
+	if minp.x < XMIN or maxp.x > XMAX
+	or minp.y < YMIN or maxp.y > YMAX
+	or minp.z < ZMIN or maxp.z > ZMAX then
+		return
+	end
+	
+	--determine if there's enough spacing between layers to start a realm
+	local chulay = math.floor((minp.y + 32) / 80) -- chunk layer number, 0 = surface chunk
+	if math.fmod(chulay, CHUINT) ~= 0 then -- if chulay / CHUINT has a remainder
+		return
+	end
+	
+	--easy to reference variables for limits and time
+	local t1 = os.clock()
+	local x1 = maxp.x
+	local y1 = maxp.y
+	local z1 = maxp.z
+	local x0 = minp.x
+	local y0 = minp.y
+	local z0 = minp.z
+	
+	--let people know you're generating a realm
+	print ("[caverealms] chunk minp ("..x0.." "..y0.." "..z0..")")
+	
+	--fire up the LVM
+	local vm, emin, emax = minetest.get_mapgen_object("voxelmanip")
+	local area = VoxelArea:new{MinEdge=emin, MaxEdge=emax}
+	local data = vm:get_data()
+	
+	--grab content IDs
+	local c_air = minetest.get_content_id("air")
+	local c_crystal = minetest.get_content_id("caverealms:glow_crystal")
+	local c_gem = minetest.get_content_id("caverealms:glow_gem")
+	local c_grass = minetest.get_content_id("caverealms:dirt_with_grass")
+	
+	--some mandatory values
+	local sidelen = x1 - x0 + 1 --usually equals 80
+	local chulens = {x=sidelen, y=sidelen, z=sidelen} --position table to pass to get3dMap_flat
+	local minposxyz = {x=x0, y=y0, z=z0}
+	local minposxz = {x=x0, y=z0}
+
+	--generate the all important perlin that makes nice terrains
+	local nvals_cave = minetest.get_perlin_map(np_cave, chulens):get3dMap_flat(minposxyz)
+	local nvals_cluster = minetest.get_perlin_map(np_cluster, chulens):get3dMap_flat(minposxyz)
+
+	local nvals_wave = minetest.get_perlin_map(np_wave, chulens):get2dMap_flat(minposxz)
+	
+	--more values
+	local nixyz = 1 --short for node index xyz
+	local nixz = 1 --node index xz
+	local stable = {} --stability for ground
+	local dirt = {} --table for dirt
+	local chumid = y0 + sidelen / 2 --middle of the current chunk
+	
+	for z = z0, z1 do --for each xy plane progressing northwards
+		for x = x0, x1 do 
+			local si = x - x0 + 1 --stability index
+			dirt[si] = 0 --no dirt here... yet
+			local nodename = minetest.get_node({x=x,y=y0-1,z=z}).name --grab the name of the node just below
+			if nodename == "air"
+			or nodename == "default:water_source"
+			or nodename == "default:lava_source" then --if a cave or any kind of lake
+				stable[si] = 0 --this is not stable for plants or falling nodes above
+			else -- all else including ignore in ungenerated chunks
+				stable[si] = STABLE --stuff can safely go above
+			end
+		end
+		for y = y1, y0, -1 do -- for each x row progressing downwards
+			local vi = area:index(x0, y, z) --grab the index of the node to edit
+			for x = x0, x1 do -- for each node do
+				--here's the good part
+				local si = x - x0 + 1 --stability index
+				local cavemid = chumid + nvals_wave[nixz] * WAVAMP --grab the middle of the cave's amplitude
+				local grad
+				if y > cavemid then
+					grad = ((y - cavemid) / HISCAL) ^ HIEXP --for the ceiling
+				else
+					grad = ((cavemid - y) / LOSCAL) ^ LOEXP --for the floor
+				end
+				local density = nvals_cave[nixyz] - grad --how dense is the emptiness?
+				if density < 0 and density > -0.7 then -- if cavern "shell"
+					data[vi] = c_air --make emptiness
+					if y < cavemid and density < STOTHR and stable[si] <= STABLE then
+						dirt[si] = dirt[si] + 1
+					else
+						stable[si] = stable[si] + 1
+					end
+					
+				elseif y < cavemid and dirt[si] >= 1 then -- node above surface
+					--place dirt on floor, add plants
+					data[vi] = c_grass
+					--on random chance, place glow crystal formations
+					if math.random() <= CRYSTAL then
+						caverealms:crystal_stalagmite(x, y, z, area, data)
+					end
+					--randomly place glow gems
+					if math.random() < GEMCHA then
+						local gi = area:index(x,y+1,z)
+						data[gi] = c_gem
+					end
+					dirt[si] = 0
+				else -- solid rock
+					stable[si] = 0
+				end
+				nixyz = nixyz + 1 --increment the 3D index
+				nixz = nixz + 1 --increment the 2D index
+				vi = vi + 1 --increment the area index
+			end
+			nixz = nixz - 80 --shift the 2D index down a layer
+		end
+		nixz = nixz + 80 --shift the 2D index up a layer
+	end
+	
+	--write these changes to the world
+	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() - t1) * 1000) --grab how long this took
+	print ("[caverealms] "..chugent.." ms") --tell people how long it took
+end)