Function to spawn players at surface and scattered

README.txt

@@ -1,4 +1,4 @@
-riverdev 0.4.5 by paramat
+riverdev 0.4.6 by paramat
 For latest stable Minetest back to 0.4.8
 Depends default
 Licenses: code WTFPL

functions.lua

@@ -158,3 +158,146 @@ minetest.register_abm({
 	end,
 })
 
+-- Set mapgen parameters
+
+minetest.register_on_mapgen_init(function(mgparams)
+	minetest.set_mapgen_params({mgname="singlenode"})
+end)
+
+-- Spawn player. Only works with chunksize = 5 mapblocks
+
+function spawnplayer(player)
+	local PSCA = 16 -- Player scatter. Maximum distance in chunks (80 nodes) of player spawn from (0, 0, 0)
+	local YWATER = 1
+	local YTER = -64 -- Deepest seabed y
+	local TERSCA = 512 -- Terrain vertical scale in nodes
+	local BASAMP = 0.3 -- Base amplitude relative to 3D noise amplitude. Ridge network structure
+	local MIDAMP = 0.05 -- Mid amplitude relative to 3D noise amplitude. River valley structure
+
+	local np_terrain = {
+		offset = 0,
+		scale = 1,
+		spread = {x=192, y=192, z=192},
+		seed = 5900033,
+		octaves = 4,
+		persist = 0.67
+	}
+	local np_mid = {
+		offset = 0,
+		scale = 1,
+		spread = {x=768, y=768, z=768},
+		seed = 85546,
+		octaves = 5,
+		persist = 0.4
+	}
+	local np_base = {
+		offset = 0,
+		scale = 1,
+		spread = {x=3072, y=3072, z=3072},
+		seed = -990054,
+		octaves = 2,
+		persist = 0.4
+	}
+	local np_patha = {
+		offset = 0,
+		scale = 1,
+		spread = {x=768, y=768, z=768},
+		seed = 7000023,
+		octaves = 4,
+		persist = 0.4
+	}
+	local np_pathb = {
+		offset = 0,
+		scale = 1,
+		spread = {x=768, y=768, z=768},
+		seed = 23,
+		octaves = 4,
+		persist = 0.4
+	}
+
+	local xsp
+	local ysp
+	local zsp
+	for chunk = 1, 128 do
+		print ("[riverdev] searching for spawn "..chunk)
+		local x0 = 80 * math.random(-PSCA, PSCA) - 32
+		local z0 = 80 * math.random(-PSCA, PSCA) - 32
+		local y0 = 80 * math.floor((YWATER + 32) / 80) - 32
+		local x1 = x0 + 79
+		local z1 = z0 + 79
+		local y1 = y0 + 79
+
+		local sidelen = 80
+		local chulensxyz = {x=sidelen, y=sidelen, z=sidelen}
+		local minposxyz = {x=x0, y=y0, z=z0}
+		local chulensxz = {x=sidelen, y=sidelen, z=sidelen}
+		local minposxz = {x=x0, y=z0}
+	
+		local nvals_terrain = minetest.get_perlin_map(np_terrain, chulensxyz):get3dMap_flat(minposxyz)
+
+		local nvals_mid = minetest.get_perlin_map(np_mid, chulensxz):get2dMap_flat(minposxz)
+		local nvals_base = minetest.get_perlin_map(np_base, chulensxz):get2dMap_flat(minposxz)
+		local nvals_patha = minetest.get_perlin_map(np_patha, chulensxz):get2dMap_flat(minposxz)
+		local nvals_pathb = minetest.get_perlin_map(np_pathb, chulensxz):get2dMap_flat(minposxz)
+
+		local nixyz = 1
+		local nixz = 1
+		for z = z0, z1 do
+			for y = y0, y1 do
+				for x = x0, x1 do
+					local n_patha = nvals_patha[nixz]
+					local n_abspatha = math.abs(n_patha)
+					local n_pathb = nvals_pathb[nixz]
+					local n_abspathb = math.abs(n_pathb)
+
+					local n_terrain = (nvals_terrain[nixyz] + 2) / 2
+					local n_absmid = (math.abs(nvals_mid[nixz])) ^ 0.8
+					local n_absbase = (math.abs(nvals_base[nixz])) ^ 0.8
+			
+					local n_invbase = (1 - n_absbase)
+					local grad = (YTER - y) / TERSCA
+					local densitybase = n_invbase * BASAMP + grad
+					local densitymid = n_absmid * MIDAMP + densitybase
+					local density = n_terrain * n_invbase * n_absmid * n_abspatha ^ 1.5 * n_abspathb ^ 1.5 + densitymid
+
+					if y >= YWATER and density > -0.01 and density < 0 then
+						ysp = y + 1
+						xsp = x
+						zsp = z
+						break
+					end
+					nixz = nixz + 1
+					nixyz = nixyz + 1
+				end
+				if ysp then
+					break
+				end
+				nixz = nixz - 80
+			end
+			if ysp then
+				break
+			end
+			nixz = nixz + 80
+		end
+		if ysp then
+			break
+		end
+	end
+	if ysp then
+		print ("[riverdev] spawn player ("..xsp.." "..ysp.." "..zsp..")")
+		player:setpos({x=xsp, y=ysp, z=zsp})
+	else	
+		print ("[riverdev] no suitable spawn found")
+		player:setpos({x=0, y=0, z=0})
+	end
+end
+
+minetest.register_on_newplayer(function(player)
+	spawnplayer(player)
+end)
+
+minetest.register_on_respawnplayer(function(player)
+	spawnplayer(player)
+	return true
+end)
+

init.lua

@@ -1,12 +1,9 @@
--- riverdev 0.4.5 by paramat
+-- riverdev 0.4.6 by paramat
 -- For latest stable Minetest and back to 0.4.8
 -- Depends default
 -- License: code WTFPL
 
--- overlen variable
--- remove autumn trees
--- remove freshwater bucket
--- remove unused schem folder
+-- spawnplayer function
 
 -- Parameters
 
@@ -137,10 +134,6 @@ riverdev = {}
 dofile(minetest.get_modpath("riverdev").."/functions.lua")
 dofile(minetest.get_modpath("riverdev").."/nodes.lua")
 
-minetest.register_on_mapgen_init(function(mgparams)
-	minetest.set_mapgen_params({mgname="singlenode"})
-end)
-
 -- On generated function
 
 minetest.register_on_generated(function(minp, maxp, seed)
@@ -184,9 +177,10 @@ minetest.register_on_generated(function(minp, maxp, seed)
 	local c_freshwaterflow = minetest.get_content_id("riverdev:freshwaterflow")
 	local c_mixwaterflow = minetest.get_content_id("riverdev:mixwaterflow")
 	
-	local sidelen = x1 - x0 + 1 -- chunk sidelen
-	local overlen = sidelen + 1 -- overgeneration sidelen
-	local emerlen = sidelen + 32 -- voxelmanip emerged area sidelen
+	local sidelen = x1 - x0 + 1 -- mapgen chunk side length
+	local overlen = sidelen + 1 -- perlinmap overgeneration horizontal side length
+	local emerlen = sidelen + 32 -- voxelmanip emerged volume edge length
+	--local emerarea = emerlen ^ 2 -- voxelmanip emerged volume face area
 	local chulensxyz = {x=overlen, y=sidelen+2, z=overlen}
 	local minposxyz = {x=x0-1, y=y0-1, z=z0-1}
 	local chulensxz = {x=overlen, y=overlen, z=sidelen} -- different because here x=x, y=z